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PubMed1986

Inhibition of tumor angiogenesis by hexuronyl hexosaminoglycan sulfate.

The efficacy of heparin (HEP), the heparin analogue hexuronyl hexosaminoglycan sulfate (HHS), and hydrocortisone (HC) was studied in inhibiting the growth of four morphologically distinct pancreatic adenocarcinoma lines (CBP, LHP2, LSP3, and Pour-LVG) in hamsters. Animals were inoculated with LD100 doses of one of the four tumor lines and were randomly allocated to groups of five animals, which received in their drinking water either: HEP (1000 U/ml) alone, HHS (10 mg/ml) alone, HC (0.5 mg/ml) alone, HEP plus HC, HHS plus HC, or no additives (control). Tumors were measured, growth rates calculated, and nonparametric statistical comparisons made among the median growth rates of all of the treatment groups. All four tumors were tested in the rabbit cornea assay for their ability to induce angiogenesis. Extracts of tumors from control animals as well as from animals treated with HHS plus HC were prepared for quantitative testing in vitro by endothelial cell migration assay. All four tumor lines caused angiogenesis as measured in the rabbit cornea assay. A reduction in median tumor growth rates was observed in animals treated with HHS plus HC bearing the CBP, Pour-LVG, and LSP3 tumors. Similarly, in vitro capillary endothelial cell migration was decreased by HHS plus HC treatment in animals bearing CBP, Pour-LVG, and LSP3 tumors. Animals bearing the LHP2 tumor showed no effect of HHS plus HC treatment on tumor growth rate and no effect on endothelial cell migration. HEP alone, HHS alone, HC alone, and HEP plus HC showed no effect on tumor growth rate in any of the four tumors tested.

Animals↗

PubMed1995

Proliferative rate by S-phase measurement may affect cure of breast carcinoma.

BACKGROUND: Standard, nonparametric statistical methods measure the interaction of covariates with survival rate or relative risk. Conversely, parametric methods measure the interaction of covariates with the two cardinal features of malignant potential: the likelihood of cure and the median time to relapse among uncured patients. METHODS: The authors performed parametric analysis on data from 810 patients with breast cancer using relapse as the survival end point. Prognostic covariates included lymph node status, tumor size, patient age, nuclear size, S-phase by thymidine or bromodeoxy-uridine labeling, and type of adjuvant therapy (chemotherapy, radiation, or hormone therapy). Also included was the cross-product term (labeling index X chemotherapy). RESULTS: Multivariate analysis revealed that: likelihood of cure was associated positively with labeling index X chemotherapy and associated negatively with lymph node status, tumor size, and patient age; and time to relapse was associated negatively with node status, nuclear size, and labeling index. CONCLUSION: The associations of labeling index and chemotherapy with the clinical course suggest that rapidly dividing tumors have a high likelihood of cure, especially with adjuvant chemotherapy, but those not cured may have early relapse.

Adult↗

PubMed1979

Formative program evaluation and milieu therapy with alcohol abusers.

Evaluated presumably therapeutic components within a therapeutic community in terms of perceived helpfulness by patients and staff of an alcohol treatment unit. Eighteen male patients and 18 staff members participated. A nonparametric statistic was used as an index of treatment philosophy articulation or degree of value-sharing. A core of activities valued congruently by patients and staff was identified.

Adult↗

PubMed1982

Do fees help heal?

Fees for mental health services is a subject that is often discussed but seldom researched. Fee information that pertained to 112 adult outpatients who returned a follow-up questionnaire and 147 who did not return it was reviewed in light of several indices of patients' response to clinic services. The study also assessed impact of change in a facility's billing format. Differences in billing format were in terms of amount of charge and whether fees were per session or lump-sum. Nonparametric statistics were applied to determine any relationship that (a) assessment by the clinic, (b) source of payment, (c) assessment to the patient, and (d) payment had with (a) return to clinic, (b) number of sessions, and (c) reports of help and satisfaction. The only association found was between presence of third-party coverage and likelihood that the patient returned. Change in billing format did not bear upon return to the clinic or satisfaction with services rendered, but did influence payment. Finally, some of the findings suggest that payment is associated with a predisposition to honor requests and obligations.

Adult↗

PubMed2001

Articular area responses to mechanical loading: effects of exercise, age, and skeletal location.

How reliable are reconstructions of body mass and joint function based on articular surface areas? While the dynamic relationship between mechanical loading and cross-sectional geometry in long bones is well-established, the effect of loading on the subchondral articular surface area of epiphyses (hereafter, articular surface area, or ASA) has not been experimentally tested. The degree to which ASA can change in size and shape is important, because articular dimensions are frequently used to estimate body mass and positional behavior in fossil species. This study tests the hypothesis that mechanical loading influences ASA by comparing epiphyses of exercised and sedentary sheep from three age categories: juvenile, subadult, and adult (n = 44). ASA was measured on latex molds of subchondral articular surfaces of 10 epiphyses from each sheep. Areas were standardized by body mass, and compared to diaphyseal cross-sectional geometrical data. Nonparametric statistical comparisons of exercised and control individuals found no increases in ASA in response to mechanical loading in any age group. In contrast, significant differences in diaphyseal cross-sectional geometry were detected between exercised and control groups, but mostly in juveniles. The conservatism of ASA supports the hypothesis that ASA is ontogenetically constrained, and related to locomotor behavior at the species level and to body mass at the individual level, while variations in diaphyseal cross-sectional geometry are more appropriate proxies for individual variations in activity level.

Age Factors↗

PubMed1985

Application of the Kolmogorov-Smirnov test to seasonal phenomena may be inappropriate.

The Kolmogorov-Smirnov one-sample test is sometimes used to test seasonality in births or other annually cyclic phenomena. However, it is shown that the maximum deviation from expected (D) may differ by a factor of almost two if the cycle is initiated in different months. Thus, different results are possible from the same data. Unless there is a logical initiation point in a cycle, it is probably better to use other nonparametric statistical tests.

Biometry↗

PubMed2006

A new classification of HLA-DRB1 alleles differentiates predisposing and protective alleles for rheumatoid arthritis structural severity.

OBJECTIVE: A new classification of HLA-DRB1 alleles supporting the shared epitope hypothesis of rheumatoid arthritis (RA) susceptibility was recently introduced. We investigated the relevance of this classification in terms of the structural severity of RA. METHODS: The study group comprised 144 patients who were included in a prospective longitudinal cohort of French Caucasoid patients with early RA. Progression of the total radiographic damage score (Sharp/van der Heijde method) was used to quantify the structural severity of RA after 4 years of followup. HLA-DRB1 typing and subtyping were performed by polymerase chain reaction, using a panel of sequence-specific oligonucleotide probes. HLA-DRB1 alleles were classified according to the above-mentioned new system. The association between the HLA-DRB1 allele groups (S1, S2, S3P, S3D, and X) and the structural severity of RA was analyzed with nonparametric statistical tests. RESULTS: The presence of S2 alleles (HLA-DRB1*0401 and HLA-DRB1*1303) was associated with severe forms of RA (P = 0.004); a significant dose effect was observed (P = 0.01). The presence of S3D alleles (HLA-DRB1*11001, HLA-DRB1*1104, HLA-DRB1*12, and HLA-DRB1*16) was associated with benign forms of RA (P < 0.0001), and a significant dose effect was observed (P < 0.01). CONCLUSION: The studied classification of HLA-DRB1 alleles is relevant in terms of RA outcomes. Compared with a previously described classification system, this system differentiates predisposing (S2) and protective (S3D) alleles for RA structural severity, which, respectively, correspond to KRRAA and DRRAA amino acid patterns at position 70-74 of the third hypervariable region of the HLA-DRbeta chain.

Alleles↗

PubMed2007

Structural parameters of the vastus medialis muscle and its relationship to patellofemoral joint deterioration.

Vastus medialis (VM) muscle dysfunction and abnormal limb alignment are commonly observed in patients who experience changes in patellofemoral joint (PFJ) function, leading many clinicians to assume that there is a direct relationship between VM structural parameters, leg alignment, and PFJ dysfunction. This study tested the hypothesis that there is a relationship between structural parameters of the VM muscle, limb alignment, and the location and severity of patellofemoral joint deterioration (PFJD). The dissection study used 32 limbs from 24 intact cadavers. Data were collected on limb alignment, angle of VM muscle fibers below the superior aspect of the patella, length of VM inserting on the medial aspect of the patella, and severity and location of PFJD. Parametric and nonparametric statistical analyses illustrated that PFJD was most commonly located on the middle third of the medial half of the patellar articular surface. The severity of PFJD did not vary with location. There was no significant correlation between any of VM insertion length, VM fiber angle, limb alignment, and PFJD location and severity lpar;r(2) < 0.34). The results of this study did not support the hypothesis of a relationship between structural parameters of the VM muscle, limb alignment, and the location and severity of PFJD in this subject group. Future research should examine the relationship between functional parameters of the entire quadriceps muscle group and PFJ dysfunction.

Aged↗

PubMed2003

Refined measurement of outcome for adjuvant breast carcinoma therapy.

BACKGROUND: Traditional nonparametric statistical methods do not provide a quantitative measure of the lifetime benefit from adjuvant therapy. This deficiency makes it difficult to determine the long-term difference in impact between the two treatment arms of a clinical trial. METHODS: To assess the impact of breast carcinoma recurrence, parametric survival models were derived from two randomized, controlled clinical trials of adjuvant therapy for Stage II breast carcinoma. To assess time to death from causes other than breast carcinoma, actuarial models derived from 1980 Census data were used. These two models were then combined to estimate the mean time to event (MTE) as a function of patient age, with the event being either recurrence or death from other causes. The MTE was then used to measure the differential benefit between two arms of a clinical trial. RESULTS: In the first trial, differences in MTE between treatment groups varied from 2.7 years for 35-year-old patients to 1.4 years for 75-year-old patients. For this trial, the mechanism of survival benefit was an increase in time to recurrence. In the second trial, differences in MTE varied from 7.6 to 1.6 years over the same age ranges. For this trial, the mechanism of survival benefit was an increase in the likelihood of cure, i.e., an increase in the asymptote of the curve that represents proportion of patients without relapse. CONCLUSIONS: When applied to data from controlled clinical trials, MTE offers a quantitative measure of long-term outcome from adjuvant therapy. The greatest benefit is achieved when therapy that increases the likelihood of cure is provided to young patients.

Actuarial Analysis↗

PubMed2004

ABO blood group is a potent risk factor for venous thromboembolism in patients with malignant gliomas.

BACKGROUND: Venous thromboembolism (VTE) is a common cause of morbidity and mortality among patients with malignant gliomas. To investigate the pathogenesis of VTE and facilitate targeted prophylaxis strategies, the authors aimed to characterize VTE risk factors in these patients. METHODS: The authors conducted a retrospective chart review of 130 adult patients with glioma who received their primary therapy at the Johns Hopkins Hospital (Baltimore, MD) between 1991 and 2001. Symptomatic VTE was confirmed by objective radiologic testing. The association between clinical and laboratory characteristics and VTE was assessed using parametric and nonparametric statistical tests and survival analysis. RESULTS: VTE developed in 28 patients (21.5%) at a median of 4.8 months after diagnosis (interquartile range, 2.1-13.2). Patients with tumors > 5 cm were more likely to develop VTE than patients with smaller tumors (hazard ratio = 2.2; P = 0.04). For every year increase in age, the hazard ratios for thrombosis increased by 3% (P = 0.011). When stratified by ABO blood group, the hazard ratios for thrombosis were 2.7 and 9.4 for patients with blood groups A (P = 0.045) and AB (P < 0.0001), respectively, compared with patients with blood group O. No association was observed between VTE and the other patient characteristics analyzed. CONCLUSIONS: Patient age, tumor size, and particularly ABO blood group are risk factors for VTE among patients with malignant gliomas. These findings may facilitate the development of a thrombosis risk score that will allow physicians to individualize VTE prophylaxis regimens.

ABO Blood-Group System↗

PubMed2007

Venous thromboembolism occurs infrequently in meningioma patients receiving combined modality prophylaxis.

BACKGROUND: Individuals with brain tumors have an increased risk of venous thromboembolism (VTE). Within this population, patients with meningiomas have been reported to have the highest incidence, exceeding rates associated with gliomas and brain metastases. However, earlier studies did not employ VTE prophylaxis, and VTE were detected with radionuclide scans, the reliability of which has since been questioned. Therefore, we conducted a retrospective review of postoperative meningioma patients receiving contemporary VTE prophylaxis and diagnostic methods to define the current incidence of and risk factors for symptomatic VTE in this population. METHODS: Medical records were reviewed from all patients undergoing craniotomy for meningioma at Johns Hopkins Hospital in 2004 and 2005. The association between clinical characteristics and VTE was assessed using parametric and nonparametric statistical tests and survival analysis. RESULTS: A total of 224 individuals met criteria for the review. The mean age was 52 years (standard deviation [SD] 14 years), and 167 patients (75%) were women. Median follow-up time was 230 days (interquartile range [IQR], 89-428 days). VTE was diagnosed in 11 patients (4.9%; 95% confidence interval, 2.5%-8.6%) at a median of 16 days (IQR, 7-33 days) postoperatively. The development of VTE was associated with older age (mean, 68 years vs 52 years; P = .0001), male gender (P = .007), and nonambulatory status postoperatively (P < .0001). CONCLUSIONS: VTE occurs infrequently in postoperative meningioma patients who receive combined modality VTE prophylaxis. VTE risk factors in these patients include advanced age, male gender, and nonambulatory status postoperatively.

Adult↗

PubMed2001

Increased myeloperoxidase index and large unstained cell values can predict the neutropenia phase of cancer patients treated with standard dose chemotherapy.

OBJECTIVE: The objective of this study was to better understand neutropenia induced by standard dose chemotherapy and to verify if there are any hematological parameters for defining the phase and possibly the duration of neutropenia. METHODS: The kinetics of large unstained cells (LUCs) and lymphocytes was evaluated in 324 blood counts of 56 chemotherapy cycles through the use of a Technicon H2 or an ADVIA 120 hematology analyzer. Blood samples collected during the neutropenia phase were also studied by flow cytometry using a large panel of monoclonal antibodies. Parametric and nonparametric statistics were employed to compare the different variables analyzed. A linear regression between each variable before and after nadir and a simple linear correlation among the same variables in the neutropenic and recovery phase were performed. RESULTS: The percentage of LUCs reaches the higher value at nadir and the difference between the mean value of prenadir and nadir is statistically significant (P <.01). The number of LUCs increases during the pre and postnadir phase. Lymphocytes number appears stable in the prenadir phase. The MPXI index increases in the prenadir phase and falls at nadir and this difference is statistically significant(P <.01). LUCs are correlated with blasts and CD34+ cells in the pre and postnadir phase, with CD3+/CD4+ cells in the prenadir phase, and with CD2+/CD56+ in the postnadir phase. CONCLUSIONS: Our data have shown that the estimation of both percentage of LUCs and MPXI can predict the neutropenia phase and orient for its duration. The lymphocyte number may be regarded as a parameter of risk of fever after day 5 of chemotherapy and the number of blood CD34+ cells may be predicted by LUC count.

Adult↗

PubMed1986

Leukemia-related morphological features in blast cells.

This paper investigates the use of image-processing methods to detect leukemia-related morphological differences in mononuclear blast cells. Routinely prepared Pappenheim-stained blood smears were scanned in a high-resolution color TV-microscope system. Eleven blast-cell classes (OMSBC, T-ALL, OMS, ALL, LBL, IBL, AUL, AML, AMOL, AMMOL, and CML) were analyzed with the nonparametric statistical software program "Classification and Regression Trees" (CART). This paper documents the initial statistical evaluation of 62 leukemia-related morphological features that directly measure and analyze the cell-related quantifiable differences occurring in the various blast cells. The 62 cell image features include both common cytophotometric features, and new texture and color features developed for this project. This study found that each leukemia specimen contains a dominant class of blasts that correlates with the specific leukemia, plus a distribution of blasts from related diseases. The present data suggest the existence of a distribution fingerprint pattern for each leukemia.

Cell Nucleus↗

PubMed2006

Analysis of individual data from bead-based assays ("bead arrays").

INTRODUCTION: Typically, bead-based assays ("bead arrays") use the mean or median value of a population of measurements to judge ligand binding or other activity, which results in a change in fluorescence intensity. Individual bead measurements are used here to calculate population parameters integral to the measurement of a bead array. METHODS: Using a commercially-available instrument designed for bead array measurements, a set of beads were labeled with biotin and then titrated with PE-Streptavidin. Data were collected under normal machine conditions as well as variations. RESULTS: The "sensitivity" of the measurements was determined using parametric and nonparametric statistical methods as well as regression analysis over a limited range of the titration (concentration vs. response profile). CONCLUSIONS: Results at low ligand concentrations suggest that precise measurements with bead array systems require a large number of individual bead measurements to be acquired. Individual bead measurements should be used to determine the mean and confidence intervals for the calculated measurements. These results also apply to regression analysis of concentration-response profiles. Furthermore, features of the instrument can be manipulated to achieve increased sensitivity and detection of lower amounts of ligand bound to the bead populations.

Biotin↗

PubMed2006

Normal lymphocytes from leukemic samples as an internal quality control for fluorescence intensity in immunophenotyping of acute leukemias.

BACKGROUND: Multiparametric flow cytometry has become an indispensable but complex tool for the diagnosis of acute leukemias. Interpretation of immunophenotypic data within a six-parameter analytical space relies on the standardization and validation of the instrument, the reagents, and the procedure. To address whether or not residual normal lymphocytes, usually present within leukemic samples, can serve as internal quality control for fluorescence intensity, 116 leukemic and 35 normal samples were analyzed. METHODS: Eight laboratories participated in the study and recruited a total of 151 individuals including 29 patients with B-cell precursor acute lymphoblastic leukemia (BCP-ALL), 77 with acute myeloid leukemia (AML), 10 with T-cell precursor acute lymphoblastic leukemia (T-ALL), and 35 normal bone marrow donors. Lymphocytes were gated according to the CD45hi/SSClo gating strategy, after which median fluorescence intensities (MFI) as well as percentages of positive cells (%positive) for CD19, CD22, CD7, and CD3 were recorded. Nonparametric statistics were used to compare variation within and between laboratories. RESULTS: Normal lymphocytes within leukemic samples do not show substantial differences compared to lymphocytes from normal controls with respect to expression of CD19, CD22, CD7, and CD3. In particular, longitudinal control charts of MFI values for CD3 antigen provide useful information on analytical and instrument performance. CONCLUSION: Residual normal lymphocytes can serve as internal quality control for studies addressing fluorescence intensity in the setting of immunophenotyping of acute leukemias.

Acute Disease↗

PubMed2002

Impact of age on clinical care pathway length of stay after complex head and neck resection.

OBJECTIVE: This article investigates the effect of patient age on postoperative pathway length of stay (LOS) for head and neck surgery. Aggregate clinical results for 43 patients, enrolled in the CCP from June 1996-July 1997, are described. Patient age, comorbid status, and postoperative complications are analyzed with respect to impact on LOS. SETTING: Tertiary level academic medical center with an operative otorhinolaryngology volume of approximately 1200 cases per year. PATIENTS: Forty-three patients undergoing head and neck resection with primary closure, local flap, or free flap closure were enrolled on CCP from June 1996-July 1997. Length of stay, frequency of selected aggregated comorbidities, and frequencies of complications are analyzed with nonparametric statistics. A pre-pathway group of 87 consecutive patients is used for comparison. MAIN OUTCOME MEASURES: Length of stay and age. RESULTS: Median actual LOS post-pathway for the patients enrolled in the first year of the pathway was 8 days. This met the CCP target and improved on pre-pathway LOS by 5 days (p <.001). The average LOS increased 25% from 8 days to 10 days for patients older than 65 years of age (p =.036, Mann-Whitney U test). Presence of a comorbidity and a complication concomitantly was statistically associated with increased LOS though not with advancing age (p =.003). CONCLUSIONS: The CCP-reported performance improvement achieved by this pathway suggests improved resource use, and improved patient outcomes are achieved for postoperative care of head and neck surgery patients. Our experience suggests that advancing age creates a clinically significant increase in resource use represented by our finding of increasing LOS. This finding warrants further investigation.

Academic Medical Centers↗

PubMedDate not supplied

Headache as a model for assessing mild analgesic drugs.

A method for the evaluation of the efficacy of mild analgesic drugs in outpatients with nonmigrainous headache is described. During the 3-hour drug evaluation period, patients were required to record at hourly intervals their pain intensity using both a verbal rating and a visual analog scale, their pain relief, and the occurrance of side effects. The results obtained in six studies consisted of comparisons of reference compounds aspirin (1000 mg) and two analgesic combinations (containing aminophenazone, caffeine, and butalbital); test medications aspirin (500 mg), codeine (30 mg), proquazone (300 mg), and new formulations of the two analgesic combinations (aminophenazone replaced by propyphenazone); and, in every study, placebo. In a seventh study, the analgesic effects of three doses aspirin (250, 500, and 1000 mg) were compared with that of placebo. Every study was conducted under double-blind, complete crossover conditions, and between 24 and 36 patients were used in each study. Using parametric and nonparametric statistical analyses, the reference compounds and the majority of the test medications exhibited significant analgesic properties. Also, a highly significant dose--response effect was demonstrated for aspirin. It is concluded that the headache model is a practicable, reliable, and sensisive method for the evaluation of the effectiveness of mild analgesic drugs.

Adult↗

PubMed1992

Prevalence of high risk genital papillomaviruses in the Belgian female population determined by fast multiplex polymerase chain reaction.

Because in situ/filter hybridisation is not sensitive enough and because classical polymerase chain reaction (PCR) protocols are generally not sufficiently reproducible and specific, there is little accurate information on the prevalence of human papillomaviruses (HPV) 16, 18, and 33 infections in women without dyskaryotic changes of the cervix. In our hands, our Fast Multiplex PCR protocol has always been the most sensitive, specific, and reproducible DNA detection assay in all the microbiological and haematological applications we attempted (Vandenvelde C, Verstraete M, Van Beers D [1990]: Journal of Virological Methods 30:215-228; Vandenvelde C, Scheen R, Corazza F, Van Beers D [1991a]: Journal of Experimental and Clinical Hematology 33:293-297; Vandenvelde C, Scheen R, Van Beers D, Fondu P [1991b]: Journal of Experimental and Clinical Hematology 30:25-29). Using this new technique, cervical scrapes from 336 Belgian women attending the cervical cancer screening clinic were examined for the presence of these three high-risk genital papillomaviruses. Positive results were confirmed using another set of HPV-specific primers. Exactly one sixth of our population was found positive for one or more of these HPVs. Types 33 and 16 were significantly more prevalent than type 18. The nonparametric statistical analysis of the data suggests that some risk factors such as particular sexual habits, that are inversely related to age, must exist.

Adult↗