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PubMed1996

Recognizing Ullrich-Turner syndrome by discriminant analysis of craniofacial structure.

In the present paper, we propose an efficient strategy for identification of craniofacial anomalies in the Ullrich-Turner syndrome (UTS). Standardized portrait- and profile-photographs were taken of 21 UTS patients with X-monosomy and 21 normal females. Twenty-seven craniofacial parameters were read from the photographs. The data were analyzed by discriminant analysis, a multivariate statistical method. The result was a function represented by a linear combination of all those craniofacial parameters which best separate the two groups. The discriminant function was applied to 15 additional patients with UTS of various cytogenetic types. All 15 patients were classified correctly. The technique facilitates syndrome-recognition and is a contribution toward the study of karyotype-phenotype relations.

Adolescent↗
PubMed1997

Sexual dimorphism and interspecific cranial form in two capuchin species: Cebus albifrons and C. apella.

Ontogenetic patterns of sexual dimorphism and cranial form in two capuchin monkeys, Cebus albifrons and C. apella, are investigated by means of univariate, bivariate, and multivariate statistics. The analyses are based on 23 linear variables. Univariate analyses indicate that similar ontogenetic patterns of cranial sexual dimorphism are present; however, interspecific differences exist in timing. Ontogenetic scaling is present in both species' crania; however, it is more prevalent in C. albifrons. Several departures are present in cranial regions associated with orbital shape, the dental arcade, and the muscles of mastication. The latter two indicate that sexual differences in diet and/or foraging strategies may exist. Sexual selection is suggested as being the primary selective regime underlying the observed patterns of cranial sexual dimorphism in each species. Interspecific comparisons confirm that C. apella possesses a more dimorphic cranium than C. albifrons and that sexual dimorphism in C. apella begins earlier in development. Although interspecific ontogenetic scaling is present in some cranial variables, C. apella is not just a scaled-up version of C. albifrons. These sympatric congeners seem to be differentiated by variables related to the orbital region and the masticatory apparatus, as indicated by both departures from ontogenetic scaling and results of the discriminant function analysis. Ecological selection, rather than varying degrees of sexual selection, is likely to be responsible for this finding given that C. apella is known to consume hard-object foods. This is consistent with the predicted outcome of the competitive exclusion principle.

Animals↗
PubMed1998

Hypoglycaemic symptoms reported by children with type 1 diabetes mellitus and by their parents.

To compare the hypoglycaemic symptoms reported by children with Type 1 diabetes and signs observed by and symptoms reported to their parents, 101 pairs, consisting of a child with diabetes and one of their parents, were asked to report the frequency with which they experienced, or witnessed, each of 31 symptoms during hypoglycaemia. The hypoglycaemic symptoms reported by the children and the reported symptoms and signs observed by their parents were classified, using multivariate statistical analyses, and compared. Close agreement was observed between the children and their respective parents' scores for frequencies of most symptoms/signs, as demonstrated by Spearman's rank correlations (median tau s = 0.25, p < 0.02). Principal Components Analysis of the symptoms/signs observed by the parents showed three factors: autonomic, neuroglycopenic, and behavioural disturbance. Analysis of the symptoms experienced by the children also identified three factors: behavioural disturbance, malaise and a third factor consisting of a combination of autonomic and neuroglycopenic symptoms. The parents could differentiate three separate groups of reported hypoglycaemic symptoms and signs (autonomic, neuroglycopenic, and behavioural disturbance) in their children. The children reported a similar group of behavioural symptoms but did not discriminate between autonomic and neuroglycopenic symptoms. These findings have important implications for the education of parents and children with Type 1 diabetes regarding the symptoms and signs of hypoglycaemia.

Adolescent↗
PubMed1999

Clear cell carcinoma has an expression pattern of cell cycle regulatory molecules that is unique among ovarian adenocarcinomas.

BACKGROUND: The purpose of this study was to identify biologic differences between ovarian clear cell carcinoma and other ovarian adenocarcinomas by comparing the expression of cell cycle regulatory molecules and by analyzing the survival of the patients. METHODS: In 51 cases of epithelial ovarian carcinoma, the expression of the cell proliferation marker Ki-67 and that of the cell cycle regulatory molecules p53, p16, p21, p27, cyclin E, and cyclin A was studied using immunohistochemical techniques. The correlations among clinical stage, histologic subtype, labeling index for Ki-67, and expression of these cell cycle regulators were examined statistically. Multivariate survival analysis was performed using these factors in the Cox proportional hazards model. RESULTS: Clear cell carcinoma revealed such trends as low expression of both p53 and cyclin A and significantly increased expression of both p21 and cyclin E (compared with the other histologic subtypes). In all ovarian carcinomas, a very strong positive correlation (correlation coefficient 0.79; P < 0.0001) between p53 positive staining and cyclin A positive staining and a weak positive correlation (correlation coefficient 0.47; P < 0.01) between p21 positive staining and cyclin E positive staining were recognized at the level of expression of cell cycle regulatory molecules. Clinical stage was the only independent predictive factor for the survival of the patients. CONCLUSIONS: Among ovarian adenocarcinomas, clear cell carcinoma exhibits a unique pattern of expression of cell cycle regulatory molecules, though in this study the survival of the patients did not correlate with histologic subtype, only with clinical stage.

Adenocarcinoma↗
PubMedDate not supplied

Secondary tracheoesophageal puncture: factors predictive of voice quality and prosthesis use.

OBJECTIVE: To identify factors predicting prosthesis use and final speech quality in patients undergoing secondary tracheoesophageal puncture (TEP) for voice restoration alter laryngectomy. METHODS: We undertook a retrospective study of 168 patients who underwent secondary TEP at the Cleveland Clinic between June 1980 and October 1993. Factors examined were: patient demographics, extent of initial surgery, method of pharyngeal preparation, history of irradiation, insufflation test results, pharyngeal stricture, and concurrent medical conditions. Univariate and multivariate statistical analyses were performed to identify predictive factors. RESULTS: At last evaluation, 73.8% (124) of the patients were still using the prosthesis. Quality of speech was the only predictor of prosthesis use (p < .001). Phonation on the first day was achieved in 90% (151) of patients. Speech result improved significantly over the first 6 months (p < .001). Univariate analysis found that the need for reconstruction at laryngectomy (p = .04), the presence of pharyngeal stricture (p = .001), and continued prosthetic use (p < .001) were associated with the speech result. There was no significant advantage to the lack of approximation of the pharyngeal constrictors (p = .31). Stepwise logistic regression showed that only the absence of pharyngeal stricture was associated with a better-quality voice (p = .001). CONCLUSION: Tracheoesophageal puncture is a reliable method for restoring voice after laryngectomy. Prosthesis use decreases with time, and good voice quality is the only predictor of continued prosthesis use. In this series the absence of pharyngeal stricture was the only significant predictor of good to excellent speech.

Adult↗
PubMed1998

FTIR microspectroscopic study of cell types and potential confounding variables in screening for cervical malignancies.

FTIR microscopy was applied to the analysis of cell types and other variables present in Pap smears to ascertain the limitations of infrared spectroscopy in the diagnosis of cervical cancer and dysplasia. It was found that leukocytes, and in particular lymphocytes, have spectral features in the phosphodiester region (1300-900 cm[-1]) suggestive of what has previously been described as changes indicative of malignancy. Endocervical cells and fibroblasts have similar spectral features to HeLa cells and consequently could also confound diagnosis. The use of ethanol as a fixative and dehydrating agent results in retention of glycogen in cervical cell types and thus minimizes spectral changes in the glycogen region due to sampling technique. Spectra of seminal fluids exhibit strong bands in the phosphodiester/carbohydrate region; however, sperm contamination should be easily detectable by the presence of a distinctive doublet at 981/968 cm(-1). Erythrocyte spectra exhibit a reduction in glycogen band intensity, but can be discerned by a relatively low-intensity nu(s) PO2- band. Endocervical mucin spectra exhibit a reduction in glycogen bands and a very pronounced nu(s) PO2- band, which is similar in intensity to the corresponding band in HeLa cells. Thrombocytes have strong bands in the phosphodiester region, but thrombocytes can be discerned from other cell types by the presence of two small broad bands at 980 and 935 cm(-1). Candida albicans is characterized by strong bands in the polysaccharide region which could potentially obscure diagnostic bands if C. albicans is present in large numbers. Spectra of bacteria common to the female genital tract, in general, also have strong absorptions in the polysaccharide region; however, bacterial contamination is usually minimal and would not be expected to obscure cervical cell spectra. Nylon threads and bristles from cervical sampling implements produce characteristic IR profiles which allow for easy identification. Given the number of potential confounding variables associated with cervical cytology, a multivariate statistical or neural network analysis would appear to be necessary before the implementation of FTIR technology in clinical laboratories.

Biopsy↗
PubMed1981

Lymphoblastic lymphoma: a clinicopathologic study of 95 patients.

A retrospective clinicopathologic study of lymphoblastic lymphoma was based on 95 patients from the files of the Repository Center for Lymphoma Clinical Studies. All patients were treated according to different protocols of Cooperative Oncology groups sponsored by the National Cancer Institute. The patients ranged in age from 4 to 84 years, with a median of 30 years. Sixty-eight patients were male and 27 female, with respective median ages of 27 and 50 years. The male-to-female ratio was 2.5:1. Forty patients had mediastinal masses; 30 (75%) of whom were male. The median survival of all patients was 17 months (range 1-100 months). To ascertain the influence of various clinical and morphologic parameters of survival, univariate and multivariate statistical analyses were performed. Patients older than 30 years of age had significantly lower incidences of mediastinal involvement (P = 0.01), number of mitotic figures (P = 0.04), and development of leukemia (P = 0.02) than patients younger than 30. Whereas lymphoblastic lymphoma is generally considered to be a disease of children and young adults, this study indicates that lymphoblastic lymphoma occurs in all age groups. These findings further suggest that lymphoblastic lymphoma may have a different biologic behavior in older patients.

Adolescent↗
PubMed1985

Reanalysis of the RTOG study of the palliation of symptomatic osseous metastasis.

This is a reanalysis of the data from the Radiation Therapy Oncology Group (RTOG) study of the palliation of metastasis to bone. The RTOG multicenter clinical trial studied pain relief in 759 patients randomly assigned to a variety of dose-fractionation schedules: 270 cGy X 15 fractions, 300 X 10, 300 X 5,400 X 5, and 500 X 5. The multivariate statistical technique of logistic regression was used. The results differed from a previous report in that number of fractions was statistically significantly related to complete combined relief (that is, absence of pain and cessation of the use of narcotics). Also, the time dose factor (TDF) isoeffect conversion did not accurately predict tumor response. The conclusion is that protracted dose-fractionation schedules are more effective than short course schedules.

Bone Neoplasms↗
PubMed1985

The validity of Pap smear parameters as predictors of endometrial pathology in menopausal women.

Cytopathologists recognize that certain Pap smear findings are suspicious for endometrial pathology in menopausal women. To study their prognostic importance in the directed cervical smear, six parameters were used to evaluate smears for evidence of an endometrial lesion: the presence of (1) histiocytes, (2) multinucleated histiocytes, (3) nonspecific inflammation, (4) bleeding, (5) elevated squamous cell maturation index, and (6) the degree of cytologic atypicality of endometrial glandular cells, expressed as a "score" from 0 to 6. Clinical pathologic correlation of 102 women with these parameters was undertaken. A multivariable statistical analysis determined which of these six parameters was most predictive of an endometrial lesion. Cytologically "scored" endometrial glandular cells was the only parameter predictive of endometrial pathology. Its emergence as the sole prognostic cervical Pap smear parameter for endometrial pathology has not been previously reported. This predictive value was consistent even with control for bleeding history and age. Appropriate interpretation of abnormal Pap smear findings contributes substantial diagnostic information in the evaluation of the endometrium.

Adenocarcinoma↗
PubMed1988

Factors of prognostic importance in childhood non-Hodgkin's lymphoma treated with two modified LSA2-L2 protocols. A multivariate analysis approach.

The results of therapy given to 74 children with advanced disease, abdominal non-Hodgkin's lymphoma were retrospectively evaluated with respect to the major prognostic factors related to disease outcome. The first 36 patients admitted in the study were treated with a modified LSA2-L2 protocol, and the remaining patients received the same regimen with the addition of intermediate-dose methotrexate (MTX) intravenously during the induction phase (LSA2-L2-MTX). The last ten patients admitted were given a leucovorin rescue along with the administration of MTX. The relative efficacy of the LSA2-L2-MTX over the baseline LSA2-L2 regimen was analyzed by multivariate statistical methods taking into consideration several candidate coprognostic factors. The risk of treatment failure was substantially reduced (55%) with the use of the LSA2-L2-MTX regimen. Rescue with leucovorin did not contribute a further significant gain in treatment efficacy, although fewer toxicity-related problems were observed as compared to the no-rescue period. Five prognostic factors emerged as significantly explanatory of the risk of treatment failure in addition to protocol type: lymphocyte count, disease stage, surgical debulking, sex, and nutritional status. Based on these variables, a logistic regression equation could be derived to identify groups that were at risk for treatment failure.

Abdominal Neoplasms↗
PubMed1992

The role of emerging technologies in the diagnosis and staging of neoplastic diseases.

The revolution in cell and molecular biology presents an unprecedented opportunity to develop an understanding of neoplastic diseases. The emerging technologies resulting from this revolution also present an opportunity to make the diagnosis and staging of neoplastic diseases more accurate. Unfortunately, the integration of these technologies into current clinical practice is not a simple task. The problems associated with the clinical applications of these technologies include standardization and simplification of the technologies so that they can be established in nonresearch institutions, selection of those technologies which provide clinically meaningful information, and finally, the implementation of large-scale clinical trials which will permit multivariate statistical analyses to determine if performance of the new studies actually add to a physician's ability to diagnose and stage cancer patients. In the future, the staging of patients with neoplastic diseases will include anatomic studies together with morphologic and biologic studies of the tumor cells. Data derived from these studies will be used to assess each patient's risk status regarding the likelihood of local and distant metastases being present. These highly accurate estimates of risk status will lead to an improvement in our ability to make individualized recommendations for therapy.

Forecasting↗
PubMed1992

Prognostic factors in survival of bladder cancer.

Clinical and pathologic data of 36 patients with transitional cell carcinoma of the bladder were investigated to determine the significance on patient survival of these factors: pathologic grade and stage; the immunohistochemistry of eight cell and tumor markers; nuclear DNA flow cytometric parameters; and patient smoking status. The bivariate and multivariate statistical analysis significantly correlated patient survival rates with the immunohistochemical expression of blood group, isoantigens A (P less than 0.05), O(H) (P = 0.001), the oncogene-related protein ORP-p21 (P less than 0.05), the pathologic grade and stage (P = 0.002), and the tumor DNA ploidy (P less than 0.05). Smoking status correlated aneuploidy (P less than 0.05) and tumor expression of ORP-p21 (P less than 0.05) with the patient survival rate. Despite the relatively small number of patients in this study, the results suggest that the clinicopathologic variables are significant factors in survival of bladder cancer.

ABO Blood-Group System↗
PubMed1992

Pain in ambulatory patients with lung or colon cancer. Prevalence, characteristics, and effect.

BACKGROUND: Few studies have evaluated the epidemiology and effect of pain in ambulatory patients with cancer who are undergoing active therapy. This information is needed to develop strategies for supportive care in this population. METHODS: The prevalence and characteristics of pain were determined in a prospective survey of ambulatory patients with lung or colon cancer. To reduce bias and acquire comprehensive information, the methodology used face-to-face interviews by trained quality assurance analysts, a multifaceted assessment instrument, and multivariate statistical analysis. RESULTS: In a telephone interview, "persistent or frequent" pain during the previous 2 weeks was reported by 57 of 145 (39.3%) patients with lung cancer and 52 of 181 (28.7%) patients with colon cancer; 91 of these patients (47 lung and 44 colon) were interviewed in detail. All patients had excellent performance status, and with the exception of pain location, there were no significant differences between the two tumor types. One-third of the patients had more than one discrete pain. Median pain duration was 4 weeks (range, less than 1 week-468 weeks), and average pain intensity was moderate. Approximately 90% of patients experienced pain more than 25% of the time. Pain interfered moderately or more with general activity and work in approximately half of the patients; more than half reported moderate or greater pain interference in sleep, mood, and enjoyment of life. Multiple regression analysis revealed that the daily frequency of pain, the intensity of the worst pain, the score on a mood scale, and the frequency of the worst pain accounted for 58.7% of the variance in average pain intensity. Likewise, 52.1% of the variance in a derived measure of pain interference in function was explained by the mood score, frequency of the worst pain, number of pains, and pain intensity. CONCLUSIONS: These data indicate that pain is prevalent among well-functioning ambulatory patients and substantially compromises function in approximately half of the patients who experience it. Pain is a complex symptom; aspects other than intensity, such as frequency, strongly influence its effect.

Aged↗
PubMed1993

Ovarian dysplasia: nuclear texture analysis.

BACKGROUND: Ovarian dysplasia has been defined by histologic and morphometric studies focusing on architectural and nuclear profile changes. A new technique is used to enhance the accuracy of this diagnosis by a quantitative evaluation of the nuclear texture that represents the nuclear chromatin pattern on which conventional diagnoses of malignancy are usually made. METHODS: Histologic sections from 35 ovaries classified as malignant (12), dysplastic (12), and normal (11) were evaluated by tracing boundaries of nuclear profiles and measuring "textons" (texture primitives) with a histogram analysis of three zones of gray level densities (called for simplification white, gray, and dark). The average combined area was tabulated for specimens with the same diagnosis, and linear regression plots compared the texton area with total nuclear area. RESULTS: The dimensions of textons originally hidden inside the chromatin and revealed by histograms were found to be closely clustered in normal epithelium, and increasingly dissociated from the containing nucleus as the lesion progressed from dysplastic to malignant. The statistical multivariate analysis including nine parameters correctly classified the three diagnostic categories as normal, dysplastic, and malignant. CONCLUSIONS: Computerized image analysis of nuclear texture adds accuracy to the recently elaborated morphometric methods to define ovarian dysplasia, a potential precursor of ovarian carcinoma.

Cell Nucleus↗
PubMed1994

Influence of surgical margins on outcome in patients with preoperatively irradiated extremity soft tissue sarcomas.

BACKGROUND: Limb-sparing surgery for soft tissue sarcomas of the extremities may result in microscopically positive surgical margins. The consequences of these microscopically positive margins are unknown. We have analyzed the influence of surgical margins on local disease control and overall survival in patients with extremity soft tissue sarcomas who received preoperative radiation therapy followed by limb-sparing surgery. METHODS: Ninety-five consecutive patients with intermediate and high grade extremity sarcomas who received preoperative radiation therapy and limb-sparing surgery were identified from a soft tissue sarcoma data-base. The clinical outcome of 24 patients who had microscopically positive surgical margins was compared with that of 71 patients who had clear surgical margins. RESULTS: Multivariate statistical analysis revealed that patients with microscopically positive surgical margins or intraoperative tumor violation had an increased risk for local failure. High grade, large size, and intraoperative violation of the tumors were associated with decreased overall survival. However, neither the presence of a positive surgical margin nor the occurrence of a local failure adversely affected overall survival. CONCLUSIONS: Achieving negative surgical margins in patients with intermediate and high grade extremity sarcomas enhances local disease control but does not measurably improve overall survival. These data should be factored into patient management decisions in cases where the goal of achieving clear surgical margins requires amputation or the significant functional compromise of the extremity.

Actuarial Analysis↗
PubMed1994

Determinants of receiving breast-conserving surgery. The Surveillance, Epidemiology, and End Results Program, 1983-1986.

BACKGROUND: Although breast-conserving surgery was used with increasing frequency during the 1980s for management of breast cancer, most women still undergo mastectomy, and a substantial variation has been documented in the proportion of women receiving breast-conserving surgery across regions of the country. Using data from the Surveillance, Epidemiology, and End Results (SEER) Program for 1983-1986, we assessed characteristics of the county of residence as predictors of receipt of breast-conserving surgery and determined whether regional variation persisted after considering these characteristics. METHODS: The data used involved all 19,661 non-Hispanic white women with localized breast cancer diagnosed in 1983 through 1986 in the nine SEER regions. Information on county characteristics was obtained from standard sources and merged with the SEER data. Univariate multivariate statistical methods were used to assess the effects of county characteristics on type of surgery for breast cancer. RESULTS: As anticipated, age was a strong predictor of type of surgery. In analyses that controlled for age, county characteristics that significantly predicted receipt of breast-conserving surgery included physician-to-population ratio, education and income levels, the presence of cancer center, and the presence of a city of at least 100,000. After controlling for these factors using multiple logistic regression, substantial regional variation persisted. CONCLUSIONS: Regional variation in treatment of localized breast cancer across the SEER regions is not explained by patient's age or county characteristics. Research is needed to address the decision making of individual patients and their physicians regarding type of surgery.

Aged↗
PubMed2001

Pattern recognition in flow cytometry.

BACKGROUND: Analytical flow cytometry (AFC), by quantifying sometimes more than 10 optical parameters on cells at rates of approximately 10(3) cells/s, rapidly generates vast quantities of multidimensional data, which provides a considerable challenge for data analysis. We review the application of multivariate data analysis and pattern recognition techniques to flow cytometry. METHODS: Approaches were divided into two broad types depending on whether the aim was identification or clustering. Multivariate statistical approaches, supervised artificial neural networks (ANNs), problems of overlapping character distributions, unbounded data sets, missing parameters, scaling up, and estimating proportions of different types of cells comprised the first category. Classic clustering methods, fuzzy clustering, and unsupervised ANNs comprised the second category. We demonstrate the state of the art by using AFC data on marine phytoplankton populations. RESULTS AND CONCLUSIONS: Information held within the large quantities of data generated by AFC was tractable using ANNs, but for field studies the problem of obtaining suitable training data needs to be resolved, and coping with an almost infinite number of cell categories needs further research.

Flow Cytometry↗
PubMed1982

Loneliness as a function of selected personality variables.

Hypothesized that in a multivariate statistical model, selected personality variables, depression, anxiety, neuroticism, psychoticism, misanthropy, and external locus of control, could positively predict loneliness, and self-esteem and extraversion could negatively predict loneliness scores. Two groups of Ss were studied independently. Ss in Group I were 232 Iranian college students (156 males, 76 females) who were studying in American colleges. Group II consisted of 305 Iranian students (168 males, 137 females) who were studying in Iranian universities. The obtained results, applying multiple regression analysis, confirmed the directions stated in the research hypothesis. However, some of the selected variables did not contribute significantly in the regression equations. Because of fluctuation of the regression coefficients, due to multicolinearity, the data were subjected to factor analysis. Two factors emerged with eigenvalues greater than unity. Loneliness loaded heavily on the first factor, which was identified as negative attribute of personality.

Adult↗