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P Nichols

Publications and source records attributed to P Nichols.

At least 37 records · Page 2Linked to original sources
PubMed1995

Nodal benign and malignant monocytoid B cells with and without follicular lymphomas: a comparative study of follicular colonization, light chain restriction, bcl-2, and t(14;18) in 39 cases.

As part of an effort to develop a better understanding of the relationship between nodal monocytoid B-cell lymphomas (MBCLs) and follicular lymphomas (FLs) when they coexist (MBCL + FL) and to assess the validity of the morphological criteria for the latter diagnosis, we evaluated follicular colonization, bcl-2 reactivity, light chain restriction, and the presence of t(14;18) in 14 benign lymph node specimens containing benign monoclonal B cells (MBCs), in eight nodal specimens of pure MBCL, and in 17 nodal specimens of MBCL coexisting with FL (MBCL + FL). Follicular colonization by malignant MBCs was observed in six specimens of pure MBCL and in 13 specimens of MBCL + FL. Benign MBCs did not express bcl-2 by immunohistological methods in 11 of 12 benign specimens. In contrast, weak reactivity for bcl-2 was detected in malignant MBCs in four of five specimens of pure MBCL and in the MBCL component in 13 of 15 specimens from the MBCL + FL group. In the FL component of 13 specimens, the bcl-2 was strongly positive. Identical light chain restriction was detected by immunohistological methods in both the FL component and the MBCL component in 15 specimens of MBCL + FL. Polymerase chain reaction analysis did not detect the t(14;18) translocation in any of 10 benign specimens or any of six evaluable pure MBCL specimens. In contrast, the translocation was detected in whole sections from eight of 12 specimens of MBCL + FL. Thus, on the one hand, the high incidences of follicular colonization and the coexistence of MBCL and FL as well as the identical light chain restriction in MBCL and FL components of MBCL + FL cases suggest that possibly these are related closely when they coexist. On the other hand, the bcl-2 and t(14;18) data cannot be used as evidence in support of a close relationship.

Chromosomes, Human, Pair 14↗
PubMed1995

Body weight, dieting, and eating disorder symptoms among college students, 1982 to 1992.

OBJECTIVE: The authors sought to examine changes in prevalence of dieting behavior and eating disorder symptoms from 1982 to 1992. METHOD: In 1982, 625 women and 276 men participated in a study examining body weight, eating habits, dieting tendencies, and eating disorder symptoms. Ten years later 564 women and 235 men at the same college completed a nearly identical survey. Similar random sampling methods were used for both studies. All respondents were classified into one of five groups (nondieter, dieter, problem dieter, subclinical eating disorder, or eating disorder according to DSM-III-R criteria). RESULTS: On almost all measures there were significant reductions of problematic eating behaviors and disordered attitudes about body, weight, and shape from 1982 to 1992. The estimated prevalence of bulimia nervosa dropped from 7.2% to 5.1% for women and from 1.1% to 0.4% for men. Binge eating, vomiting, diuretic use, and diet pill use also declined for women during this period. Significantly fewer women and men reported chronic dieting in 1992 than in 1982, and there was evidence of improved body image for both sexes. Subjects in 1992 also reported healthier eating habits in terms of dietary intake and meal regularity. Finally, women in 1992 were more likely to be overweight and were, on average, five pounds heavier than their 1982 counterparts. CONCLUSIONS: The prevalence of problematic eating behaviors and eating disorder symptoms appears to be abating. However, they remain a significant problem that affects a substantial segment of this population.

Adult↗
PubMed1995

Pigeons' preference for variable-interval water reinforcement under widely varied water budgets.

Water budget of pigeons was varied to assess the dependence of risk-sensitive preferences upon economic context such as has been reported for energy-budget manipulations with small animals in behavioral ecology research. Fixed- and variable-interval terminal-link water schedules reinforced choice between equal variable-interval initial-link schedules arranged on two pecking keys. While keeping a severely restrictive budget the same across three phases of the experiment, a contrasting distinct ample budget was arranged in each. To mimic typical methods in behavioral ecology studies, in each ample budget a more than three-fold increase in amount of water per reinforcer presentation was instituted simultaneously with significantly increased overall access to water. Total choice response rates plummeted in the ample budgets, and body weights either increased significantly or remained unchanged in different phases as expected by the nature of the different manipulations. Clear preferences for the variable-interval schedule were found throughout the experiment, except for rare instances of key bias. The results agree with similar operant food-reinforcement studies and extend conditions under which risk preference apparently does not depend upon economic context.

Animals↗
PubMed1993

Evaluation of a school-site cardiovascular risk factor screening intervention.

BACKGROUND: Though several published reports have demonstrated the feasibility of conducting school-site cardiovascular risk factor screening programs as well as the ability of such programs to detect high-risk children and parents, less is known about their cognitive and behavioral impact. METHODS: Four Michigan elementary schools received a cardiovascular risk factor screening intervention twice between spring 1989 and spring 1990 and four other area schools served as comparison sites. All eight schools received the Michigan Model Comprehensive School Health Education Program. RESULTS: Among participating students (n = 1,166) and their parents (n = 514), significant favorable changes in relevant health knowledge as well as attitudes regarding nutrition and early detection of disease relative to comparison student (n = 480) and parents (n = 158), were observed. There was also a significant decrease in students' self-reported intake of high-fat foods and parents of children who participated were themselves significantly more likely to report having had their cholesterol and blood pressure tested. CONCLUSIONS: This quasi-experimental study suggests that school-based risk factor screening programs can positively influence the knowledge, attitude, and behavior of schoolchildren and their parents and may, therefore, represent a potentially effective adjunct to traditional curricular approaches to disease prevention and health education as well as an alternative means of early detection.

Blood Pressure↗
PubMed1993

Standards of Practice criteria: consultant dietitians in health care facilities.

Establishment of quality assurance guidelines is becoming increasingly necessary in long-term-care facilities. The Consultant Dietitians in Health Care Facilities (CD-HCF) dietetic practice group of The American Dietetic Association (ADA) developed 27 documentations/outcome-oriented guidelines for quality assurance. The documentations were categorized according to the six Standards of Practice developed by ADA. The six general categories covered establishment of performance criteria, development of individual practice plans, knowledge of nutrition, self-development, research, and use of resources. We surveyed 188 members of the CD-HCF about their levels of agreement in theory with and frequency of completion for each documentation. Of the respondents, 165 (88%) were employed in long-term-care facilities. Respondents had worked as consultant dietitians for a mean of 10 years. Four standards and the total questionnaire had highly significant positive correlations between agreement in theory and frequency of completion. The findings indicate that consultant dietitians agree with the theory of the documentation and frequently complete documentation.

Consultants↗
PubMed1993

Relationship of ST-segment elevation to eventual QRS loss in acute anterior wall myocardial infarction.

The position of electrocardiographic ST-segment elevation in acute myocardial infarction (MI) is related to the region of infarction, but the relationship between the initial ST-segment elevation and the eventual loss of QRS voltage remains uncertain. The authors examined body surface map data in 76 patients with acute anterior wall MI to clarify this relationship. The patients had no evidence of previous MI, no subsequent MI, and did not receive thrombolytic therapy or other acute interventions. Maps were recorded on admission to the hospital, every 24 hours during the hospital stay, and again at follow-up examinations 6-48 months after the index MI. The region of ST-segment elevation on the initial body surface map was compared to the region of developed voltage loss in the QRS complex as measured by the integral 0-30, 0-40, 0-80, and 30-80 ms body surface maps subsequently recorded 24 hours, 48 hours, and over 6 months after the initial body surface map. There was a relationship between the position of the ST-segment elevation and the loss of the QRS segment voltages, which was pronounced early after acute MI and diminished months after the MI. The region of ST-segment elevation in the initial body surface map predicts the QRS loss. In the integral QRS0-30 map versus the initial ST-segment map the mean correlation coefficient was -0.54 +/- 0.33 with a median value of -0.67. The integral QRS0-40 map and ST-segment map had a mean correlation coefficient of 0.60 +/- 0.29 and median of 0.66. The mean correlation coefficient is less for the integral QRS0-80 map and nonexistent in the integral QRS30-80 map. This method may be useful for monitoring acute interventions in acute MI.

Electrocardiography↗
PubMed1993

The rationale for en bloc pelvic lymph node dissection for bladder cancer patients with nodal metastases: long-term results.

From August 1971 through June 1989, 591 consecutive patients underwent curative pelvic lymphadenectomy with en bloc radical cystectomy for bladder cancer. Of these patients 132 (22%) had pathologically proved nodal metastases. The incidence of positive nodes increased with increasing pathological stage of the primary tumor: stage PIS (0.75%), stage P1 (13%), stage P2 (20%), stage P3a (24%), stage P3b (42%) and stage P4 (45%). The median followup for the 31 patients still alive was 5.5 years (range 2.6 to 18.8). Recurrent bladder cancer was documented in 89 patients (67%) with a median interval to progression of 1.5 years. Pelvic recurrence as the first site of progression was uncommon, occurring in 15 patients (11%). The actuarial 2, 3, 5 and 10-year survival rates were 55%, 38%, 29% and 20%, respectively. Increased risk of progression and death was associated with advanced pathological tumor stage (stage P3b or greater, p < 0.001 and p < 0.001, respectively) and 6 or more positive nodes (p < 0.001 and p = 0.012, respectively). There was no significant difference in survival and interval to progression among patients who received preoperative irradiation or adjuvant chemotherapy compared to those treated with surgery alone. This retrospective analysis further substantiates the philosophy that single stage pelvic lymphadenectomy with en bloc radical cystectomy can provide long-term progression-free survival, particularly for patients with localized primary tumors and minimal metastatic nodal disease.

Aged↗
PubMed1991

Portal vein thrombosis complicating endoscopic variceal sclerotherapy. Convincing further evidence.

Portal vein thrombosis occurred in a patient who bled from gastric varices that developed after obliteration of esophageal varices by endoscopic sclerotherapy. This complication was recognized only at surgery when thrombectomy and endovenectomy preceded the successful placement of an end-to-side portocaval shunt. At histopathology, the presence of an amorphous, eosinophilic material staining negatively for fibrin and similar to sclerosant injected at sclerotherapy was observed within the clot. This latter finding, previously unreported, provides convincing evidence for the causal relationship of portal vein thrombosis to endoscopic sclerotherapy.

Esophageal and Gastric Varices↗
PubMed1991

Epidemiology of paramphistomosis in cattle.

The epidemiology of paramphistomosis in cattle was studied using tracer calves in a subtropical location in eastern Australia. Two species of paramphistomes were present; Calicophoron calicophorum and Paramphistomum ichikawai. The former species was the most abundant. Gyraulus scottianus and Helicorbis australiensis acted as intermediate hosts, respectively. Paramphistome burdens varied seasonally and were dependent upon the number of infected host snails. Peak fluke burdens and clinical paramphistomosis occurred in late summer in year 1 and early winter in year 2. The peak fluke burdens coincided with prolonged inundation of the grazing areas resulting in rapid multiplication and infection of host snails, and the period after the inundated areas dried out. The prevalence of infection in snails was high in both years, peaking at 98% in year 1 and 58% in year 2. The main host snail, G. scottianus, aestivated and retained infection for at least 24 weeks in soil, and in vegetable debris on the surface of the soil, resulting in rapid reappearance of host snails and infective metacercariae after the onset of seasonal rain. Metacercariae survived on herbage for up to 12 weeks, depending on the environmental conditions. Paramphistome burdens in calves could be predicted from the prevalence of infection in the host snail, the water levels and an index of surface water on the grazing site. Control of paramphistomosis during and after flooding may be achieved by removal of susceptible cattle from pasture or regular treatment during these periods. Strategic treatment during the dry season may reduce contamination of snail habitats and infectivity of the pasture in the following wet season.

Animals↗
PubMed1991

The role of adjuvant chemotherapy following cystectomy for invasive bladder cancer: a prospective comparative trial.

We assigned 91 patients with deeply invasive, pathological stage P3, P4 or N+ and Mo transitional cell carcinoma of the bladder (with or without squamous or glandular differentiation) to adjuvant chemotherapy or to observation after radical cystectomy and pelvic lymph node dissection. For most patients chemotherapy was planned as 4 courses at 28-day intervals of 100 mg./M.2 cisplatin, 60 mg./M.2 doxorubicin and 600 mg./M.2 cyclophosphamide. A significant delay was shown in the time to progression (p = 0.0010) with 70% of the patients assigned to chemotherapy free of disease at 3 years compared to 46% in the observation group. Median survival time for patients in the chemotherapy group was 4.3 years compared to 2.4 years in the observation group (p = 0.0062). In addition to treatment groups, important prognostic factors included age, gender and lymph node status. The number of involved lymph nodes was the single most important variable. We recommend adjuvant chemotherapy for patients with invasive transitional cell carcinoma after definitive surgical resection.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

L-type calcium channels may regulate neurite initiation in cultured chick embryo brain neurons and N1E-115 neuroblastoma cells.

The intracellular free Ca2+ concentration, [Ca2+]i, plays an important role in regulating neurite growth in cultured neurons. Insofar as [Ca2+]i is partly a function of Ca2+ influx through voltage-sensitive calcium channels (VSCC), Ca2+ entry through VSCC should influence neurite growth. Vertebrate neurons may possess several types of VSCC. The most frequently described VSCC types are usually designated L, T and N. In most preparations, these VSCC types respond differently to certain pharmacological agents, including Cd2+, Ni2+, the dihydropyridines nifedipine and BAY K8644, and the aminoglycoside antibiotics. We used these agents to study the role of Ca2+ influx in regulating neurite initiation and length in cultures of chick embryo brain neurons and N1E-115 mouse neuroblastoma cells. In chick neurons, nifedipine and Cd2+ (less than 50 microM), which have been reported to inhibit L-type channels, reduced neurite initiation, but not mean neurite length. Ni2+ (less than 100 microM), reported to inhibit T-type channels, had no effect on either initiation or length. Low concentrations of most aminoglycosides (less than 300 microM), reported to inhibit N-type channels, had no effect on neurite initiation, but high concentrations of streptomycin (great than 300 microM), reported to inhibit both L- and N-type channels, reduced neurite initiation. BAY K8644, which enhances current flow through L-type channels, had no effect except at high concentration (50 microM), which inhibited initiation. N1E-115 neuroblastoma cells have been reported to contain L-type and T-type channels, but thus far no channel similar to the N-type has been described. In cultured N1E-115 cells, nifedipine (5 microM), Cd2+ (5 microM), and streptomycin (200 microM) reduced neurite initiation, while nickel (50 microM) and neomycin (100 microM) did not affect initiation. None of these agents altered neurite length. In N1E-115 cells, whole-cell voltage clamp recordings showed that nifedipine and Cd2+ inhibited L-type channels but not T-type channels, while Ni2+ inhibited T-type channels but not L-type channels. Streptomycin slightly inhibited L-type channels but enhanced current flow through T-type channels. Neomycin slightly inhibited both channel types. These data indicated that neurite initiation in these two cell types may be modulated by Ca2+ influx through L-type channels, but not T- or N-type channels. Neurite length was not significantly influenced by any of the agents tested, suggesting that Ca2+ influx through VSCC may not affect neurite elongation.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1990

The role of radical cystectomy in the management of high grade superficial bladder cancer (PA, P1, PIS and P2)

Between January 1979 and 1987, 411 consecutive patients were considered candidates for bilateral pelvic iliac lymph node dissection and radical cystectomy for the management of bladder cancer. From this group 160 were identified as having pathological stage P2 or less disease, including 11 who also had positive nodes. The 5-year actuarial survival rate for the respective stages at 95% confidence limits was 100% for stage P0/A, 80% for stage P1, 78% for stage P1 with stage PIS, 85% for pure stage PIS, 76% for stage P2 and 87% for stage P2 with stage PIS. Additionally, we identified a group of patients with stage P2 transitional cell carcinoma who were at significant risk for development of metastatic disease. Of 46 patients with stage P2 transitional cell carcinoma 18 had vascular space invasion resulting in 6 of 18 cancer-related deaths (33%). Our study demonstrates that radical cystectomy has been highly effective in curing patients with high grade superficial disease, including those with superficially invasive disease associated with nodal metastases.

Carcinoma, Transitional Cell↗
PubMed1990

Parathyroidectomy in chronic renal failure: a nine-year follow-up study.

Seventy-three patients with chronic renal failure who underwent parathyroidectomy between March 1978 and April 1987 were reviewed. Thirty-four patients had undergone sub-total parathyroidectomy, and 39 patients had undergone total parathyroidectomy with parathyroid autograft into the forearm. Eight patients showed persistent hyperparathyroidism requiring a second surgical procedure. In all other patients there was highly statistical improvement in parathyroid hormone, total calcium, ionized calcium, alkaline phosphatase and a significant reduction in calcium x phosphate product. Histological evidence of osteitis fibrosa was present in 21 of 22 patients before surgery. Postoperatively, four showed complete resolution and improvement. Three patients developed histological evidence of osteomalacia during the study period. Only four of the 39 patients who underwent total parathyroidectomy with autograft had true recurrent hyperparathyroidism and only two of the 34 patients who underwent sub-total parathyroidectomy had recurrent disease, indicating that there is little to choose between the two techniques in the control of secondary hyperparathyroidism and its subsequent recurrence. In one patient with recurrence of hyperparathyroidism from a forearm parathyroid graft the histological picture was different from that of normal hyperplastic parathyroid tissue. Although it is probable that abnormal parathyroid tissue had been implanted there was no evidence of invasive growth into the forearm muscle. The most striking feature of long term follow-up was the difference in calcium x phosphate product in patients in whom vascular calcification increased compared to those patients with no change or regression of calcification. Mean calcium phosphate product in those patients with progressive vascular calcification was 4.93 for small and medium size vessels and 5.38 for large vessels compared to 4.10 for small and medium vessels and 4.09 for large vessels. In the former case the serum phosphate was 2.00 and 2.17 as compared to 1.75 or 1.73, suggesting that the aim in patients with end stage renal failure maintained by dialysis should be to control the serum phosphate concentration to 1.8 mmol or less and the calcium x phosphate product to less than 4.2.

Adult↗
PubMed1990

Phase I study of combination recombinant interleukin-2 and interferon gamma in patients with advanced malignancies.

A phase I trial of interleukin-2 and interferon gamma combination treatment in patients with advanced malignancies was performed based on preclinical in vitro and in vivo data which demonstrated synergistic antitumor effect. The toxicities, immune parameters, and tumor responses are described. The clinical and biologic maximal tolerated doses were extrapolated from these data.

Adolescent↗
PubMed1990

Detection of occult CNS involvement of follicular small cleaved lymphoma by the polymerase chain reaction.

A patient with follicular small cleaved lymphoma presented with an unusual clinical relapse in the central nervous system (CNS) without morphologic evidence of lymphoma cells in the cerebral spinal fluid (CSF). Molecular genetic analysis of the small number of cells in the CSF after in vitro DNA amplification by the polymerase chain reaction demonstrated the presence of an abnormal translocation sequence between chromosomes 14 and 18. A similar translocation could be detected from the original fixed archival lymph node biopsy and from a small proportion of circulating mononuclear cells. These results indicated that occult lymphoma cells were present in the CSF and peripheral blood. Secondary CNS lymphoma involvement was identified at autopsy. This case demonstrates the enhanced sensitivity of lymphoma diagnosis from poorly cellular specimens after in vitro DNA amplification.

Aged↗