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PubMed1994

The Family Adaptability and Cohesion Scale III in a Norwegian sample.

Olson's Family Adaptability and Cohesion Scales (FACES III) and Beavers' Self-report Family Inventory (SFI) were administered to 177 young Norwegian adults. Three questions were raised: (1) do the two-factor structure and curvilinear hypothesis of Olson's model of family functioning find support cross-culturally; (2) does curvilinearity depend on whether families of origin or procreation are described; and (3) does the data analytic technique dictate the results. In 1985, in their manual, Olson and his associates proposed the use of Distance from Center (DFC) scores to test the curvilinear hypothesis, a procedure that presupposes orthogonality between the dimensions of Cohesion and Adaptability, which was not found in several other samples nor in the present study. Using DFC scores, the curvilinear hypothesis received moderate support only when families of origin were described. A polynomic regression analysis gave clear evidence, however, of a linear relationship between the FACES dimensions and SFI Health Scores for both families of origin and families of procreation. The findings suggest that respondents do not have an implicit bipolar model of cohesion and adaptability.

Adult↗

PubMed1998

The three-for-one model for gram-negative wall growth: a problem and a possible solution.

The murein wall in Gram-negative bacteria is so thin that the mechanism of growth is necessarily complicated. From analytical data of murein components, Höltje suggested a model for the growth mechanism that would lead to safe wall enlargement. The model depended on the formation of trimers of peptidoglycan disaccharides linked via their pentapeptides. In the 'three-for-one' model three oligopeptidoglycan chains are linked to each other in the usual linkages between the carboxyl group of D-alanine residues and the epsilon-amino group of diaminopimelic acid residues; these are designated 'tail-to-tail' linkages. This three-chained raft is then linked to the stress-bearing wall via the formation of trimers, defined as three peptide chains linked together by tail-to-tail linkages. Then by autolyzing the oldest bonds in each trimer, the old chain is excised and the raft becomes part of the stress-bearing wall and the wall is enlarged. There is a problem with the three-for-one model in that it demands a precise fitting of the prefabricated raft of three crosslinked chains to a stress-bearing chain in the wall fabric to allow the series of trimer linkages to form. Because the wall, when bearing stress, must be pulled into a 'honeycomb' structure, the end-to-end distance would be shortened. The possibility is raised here that the glycan chains in the stress-bearing wall are stretched to a sufficient degree by the cell's turgor pressure to compensate for its zig-zag structure; this could allow the model to function. A calculation is presented that assumes that the area of the pores in the fabric, called tessera, is maximized by the cell's turgor pressure. In this case the glycan chain must stretch 10% (and the end-to-end distance of peptide strands stretch 28%) so that the end-to-end distance of a glycan chain in the stress-bearing wall and the unstretched nascent wall can be the same and permit indefinite stable growth.

Carbohydrate Sequence↗

PubMed1993

The Prenatal Development Project.

The primary aim of the Prenatal Development Project (PDP) is to evaluate the developmental effects of prenatal exposure to steroid hormones and psychoactive drugs, particularly synthetic progestin, corticosteroids and barbiturates. Data collection has taken place at the Psykologisk Institut, now the Institute of Preventive Medicine, since 1981. The PDP database is unique for its breadth and depth as well as its combination of prospective longitudinal and cross-sectional perspectives. This article describes the database, including subject selection, perinatal information, the comprehensive contemporary evaluation and archival information from Danish registers. The unique matching procedures designed specifically for these projects and data analytic strategies are explained. The value of the PDP database is discussed both in relation to specific project aims (evaluating effects of prenatal drug exposure) and in relation to developmental and psychological research in general.

Adult↗

PubMed1987

Difficulties encountered in the search for the etiologic agents of destructive periodontal diseases.

The present paper outlines some of the difficulties encountered in the search for the etiologic agents of destructive periodontal diseases. These include technical problems such as acquiring an appropriate microbial sample, as well as difficulties in the dispersion, cultivation and identification of isolates in that sample. Many of these difficulties are currently being successfully addressed. A second set of problems is more conceptual in nature. These include difficulties in distinguishing between periodontal diseases and determining the state of activity of periodontal lesions. In addition, complexes of organisms and/or sequences of species may be involved in the progress of lesions. A further problem is encountered in attempting to distinguish overgrowths of opportunistic species from increases in proportions of true pathogens. Finally, it appears likely that different infections occur at the same time in a single oral cavity. The technical and conceptual difficulties eventually filter down to the data analytical step and present numerous problems to the analyst. With all of these difficulties in mind, it is not surprising that the etiologic agents of destructive periodontal diseases are not clearly defined. However, improvement in technological assessments of the microbiota and clinical evaluation of the disease should permit reasoned approaches to be taken. The delineation of the etiologic agents of destructive periodontal diseases will be, of necessity, a multistage iterative process. Etiologic agents will be suggested by predominant cultivable studies and hypotheses concerning subsets of these agents tested using more specific procedures such as selective media, immunofluorescent techniques or DNA probes.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacteria↗

PubMed1997

Chondroitin sulfate isomers in synovial fluid of healthy and diseased human temporomandibular joints.

Synovial fluid was collected from the superior articular cavity of the temporomandibular joint in patients with unilateral internal derangement and joint pain whose contralateral joint was healthy. Glycosaminoglycans were liberated by digestion with pronase E, and precipitated with cetylpyridinium chloride and ethanol. Unsaturated disaccharide isomers of chondroitin sulfate, obtained following chondroitinase ACII digestion, were analyzed by high-performance liquid chromatography. Analytic data indicated that deltaDi-0S and deltaDi-6S were often found in chondroitin sulfate from the fluid of the diseased joints. The amounts of deltaDi-0S and deltaDi-6S differed significantly between synovial fluid samples from the diseased and healthy joints. Comparison of the relative proportions of the unsaturated disaccharides in the synovial fluid with previously reported values for several tissues, indicated that the chondroitin sulfate originated from articular cartilage, with possibly some contributions from soft connective tissues and serum present in the synovial fluid. These results suggest that chondroitin sulfate in the synovial fluid provides a useful indicator of the degree of internal derangement of the temporomandibular joint.

Adult↗

PubMed1976

Defective neutrophil chemotaxis and hyperimmunoglobulinemia E-a reversible defect?

An eleven-month-old boy is presented with chronic atopic dermatitis and recurrent infections of the skin and respiratory tract, including subcutaneous abscesses. Immunological studies disclosed a neutrophil chemotactic defect, blood eosinophilia and serum hyper IgE. The clinical and analytical data are similar to those of patients previously dermatitis reversed the chemotatic defect, the blood eosinophilia and the clinical symptoms.

Chemotaxis↗

PubMed2006

Untoward effects of chronic dual renin-angiotensin system blockade: influence of previous chronic renal failure.

Dual blockade of the renin-angiotensin system (RAS) has increased antiproteinuric effects and so a higher incidence of secondary effects can be expected when this kind of treatment is administered. The aim of this study was to assess the safety of dual blockade of RAS. Seventy-five (54 men and 21 women) patients has been treated in our unit with dual RAS blockade due to proteinuria higher than 1 g/24 h. Mean age was 57.1 +/- 14.0 years. Fifty-three patients had chronic renal failure (CRF) at baseline. Analytical data of 6 months visit and last follow-up visit were recorded. A small reduction of systolic blood pressure and diastolic blood pressure was observed in both treatment groups throughout the study. Neither the CRF patients nor those with normal renal function showed any reduction in mean plasma haemoglobin levels, but differences between groups were significant at the second and third visits (anova). No change was detected in haematocrit. Mean K+ significantly increase at the second visit in the CRF group (from 4.80 +/- 0.64 to 5.23 +/- 0.81 mmol/l, p < 0.001, Student's t-test). There were no changes in normal kidney function group (4.58 +/- 0.37 vs. 4.63 +/- 0.44). At baseline plasmatic creatinine was higher in the CRF group (2.09 +/- 0.60 0.20 mg/dl vs. 0.99 +/- 0.20 mg/dl, p < 0.001, Student's t-test) and creatinine clearance was lower (48.6 +/- 20.7 ml/min vs. 107.0 +/- 0.30 ml/min, p < 0.001, Student's t-test). There was a small increase in creatinine along the follow-up when compared with the normal renal function group (p < 0.001, anova). Conversely, creatinine clearance remain unchanged in the normal renal function group, and there was a decrease in creatinine in CRF patients (p < 0.001). Dual RAS blockade seems to be safe in renal patients even when mild to moderate renal failure is present. Severe hyperkalaemia is uncommon. Small increments in plasmatic creatinine can be seen but they are hardly dangerous. Combined treatment does not significantly influence erythropoiesis.

Analysis of Variance↗

PubMed1990

The bioavailability of vitamin B6. Recent findings.

Further clarification of the bioavailability of dietary vitamin B6 requires better analytical data concerning the forms of vitamin B6 in foods as well as the overall composition of foods. The application of radioisotopic and stable-isotopic studies such as those described will provide useful information concerning the inherent bioavailability of the various vitamin B6 compounds. Additional studies should then address the influence of other dietary components on the utilization of the vitamin B6 compounds, using intrinsic and extrinsic enrichment techniques. Care must be taken in interpretation of the results of animal bioassays in the determination of the bioavailability of vitamin B6 in complex diets.

Animals↗

PubMed1995

Industry perspective on clinical trial issues for combination vaccines.

The development and production of vaccines remains complicated, largely because of the complexity of the vaccines, which are virtually always manufactured in a biological system; the nature of most vaccines precludes the use of the detailed chemical analysis that is possible for simple chemical entities. Therefore, approval and release of vaccines is dependent upon careful view of the manufacturing processes, the analytical data that are available, and data from clinical trials of consistency lots. The makeup of consistency lots from combinations, the purpose and utility of such lots, and the timing of their production depend not only on the maturity of the manufacturing process but also upon mutual agreement between the sponsor and the regulators. Consistency of application of regulations and precedent are important in the sponsor's ability to carry out successful development programs. The science of adjuvants is still in its infancy, but opportunities for it to mature are legion. Aluminum salts remain the mainstay of contemporary adjuvants but will no doubt be supplanted in the near future. The ethics of doing efficacy studies in infants who could be protected by safe and well-tolerated vaccines must be debated openly. Closely related to efficacy studies are the use of surrogates, which should be developed, recognized, and utilized. Finally, the potential utility of M-M-R IIV was shown by studies of the individual attenuated virus components in vaccines.

Adjuvants, Immunologic↗

PubMed1993

Robustness of some estimators for the analysis of covariance structures.

A sampling experiment was designed to evaluate the robustness of some estimators used in the analysis of covariance structures to misspecification of the discrepancy function in finite samples. The estimators were studied under four distribution (a multivariate normal, an elliptical, a non-elliptically symmetric, and an asymmetric multivariate distribution, and eight sample size (75, 150, 300, 600, 1200, 2400, 4800, 9600) conditions. Parameters of the composite direct product model for a 6-variable MTMM matrix were estimated using the Maximum Wishart Likelihood (MWL), generalized least squares (GLS), asymptotically distribution free (ADF), and approximate ADF (DADF) estimators. Browne's elliptical correction (CMWL) to the test statistic and standard errors for scale-invariant models was also made for each sample. Each of the 32 distribution-sample size conditions was replicated 300 times. The accuracy of the parameter estimates and estimated standard errors and the distribution of the test statistic were studied. The theoretically predicted importance of information contained in higher-order moments of arbitrary distributions was confirmed. Robustness of the MWL and normal theory GLS estimators cannot be taken for granted. Elliptical corrections may be a practical solution to some data analytic problems.

Female↗

PubMed1998

Impact-induced fissuring of articular cartilage: an investigation of failure criteria.

Several candidate predictors for the occurrence of surface fissures in cartilage, including impact force, shear stress, and tensile strain have been previously proposed without an analytic basis. In this study a controlled impact experiment was performed where a dropped mass and three impact interfaces were used to identify loads associated with the initiation of fissuring. A Finite Element Model of each experiment was used to obtain stresses and strains associated with each impact event. The resulting experimental and analytical data were analyzed using logistic regression in order to determine the strongest predictor of a fissure, and thus to propose a failure criterion for articular cartilage during a blunt insult. The logistic regression indicated that shear stress, rather than impact force or drop height (an indicator of impact energy), was the strongest predictor for the occurrence of a fissure.

Animals↗

PubMed1989

Static, dynamic, and relational properties in vowel perception.

The present work reviews theories and empirical findings, including results from two new experiments, that bear on the perception of English vowels, with an emphasis on the comparison of data analytic "machine recognition" approaches with results from speech perception experiments. Two major sources of variability (viz., speaker differences and consonantal context effects) are addressed from the classical perspective of overlap between vowel categories in F1 x F2 space. Various approaches to the reduction of this overlap are evaluated. Two types of speaker normalization are considered. "Intrinsic" methods based on relationships among the steady-state properties (F0, F1, F2, and F3) within individual vowel tokens are contrasted with "extrinsic" methods, involving the relationships among the formant frequencies of the entire vowel system of a single speaker. Evidence from a new experiment supports Ainsworth's (1975) conclusion [W. Ainsworth, Auditory Analysis and Perception of Speech (Academic, London, 1975)] that both types of information have a role to play in perception. The effects of consonantal context on formant overlap are also considered. A new experiment is presented that extends Lindblom and Studdert-Kennedy's finding [B. Lindblom and M. Studdert-Kennedy, J. Acoust. Soc. Am. 43, 840-843 (1967)] of perceptual effects of consonantal context on vowel perception to /dVd/ and /bVb/ contexts. Finally, the role of vowel-inherent dynamic properties, including duration and diphthongization, is briefly reviewed. All of the above factors are shown to have reliable influences on vowel perception, although the relative weight of such effects and the circumstances that alter these weights remain far from clear. It is suggested that the design of more complex perceptual experiments, together with the development of quantitative pattern recognition models of human vowel perception, will be necessary to resolve these issues.

Humans↗

PubMed1971

Arsenic in potable desert groundwater: an analysis problem.

An accuracy investigation, initiated because of conflicting analytical data on the arsenic content for some 24 drinkinig water locations in the Mojave Desert, revealed that interference with the evolution of arsine in the American Public Health Association silver diethyldithiocarbamate method caused either color enhancement or arsine suppression. For certain types of natural waters this method is unreliable.

Arsenic↗

PubMed1978

Bacterial oxidation of polyethylene glycol.

The metabolism of polyethylene glycol (PEG) was investigated with a synergistic, mixed culture of Flavobacterium and Pseudomonas species, which are individually unable to utilize PEGs. The PEG dehydrogenase linked with 2,6-dichlorophenolindophenol was found in the particulate fraction of sonic extracts and catalyzed the formation of a 2,4-dinitrophenylhydrazine-positive compound, possibly an an aldehyde. The enzyme has a wide substrate specificity towards PEGs: from diethylene glycol to PEG 20,000 Km values for tetraethylene glycol (TEG), PEG 400, and PEG 6,000 were 11, 1.7, and 15 mM, respectively. The metabolic products formed from TEG by intact cells were isolated and identified by combined gas chromatography-mass spectrometry as triethylene glycol and TEG-monocarboxylic acid plus small amounts of TEG-dicarboxylic acid, diethylene glycol, and ethylene glycol. From these enzymatic and analytical data, the following metabolic pathway was proposed for PEG: HO(CH2CH2O)nCH2CH2OH leads to HO(CH2CH2O)nCH2CHO leads to HO(CH2CH2O)nCH2COOH leads to HO(CH2CH2O)n-1CH2CH2OH.

Chemical Phenomena↗

PubMed1996

Natural occurrence of Fusarium mycotoxins in field samples from the 1992 Wisconsin corn crop.

Analysis of 98 moldy corn samples collected in Wisconsin between November 1992 and January 1993 for Fusarium toxins by various immunochemical assays revealed overall average mycotoxin concentrations of 305.6, 237.7, and 904.3 ng/g for type A trichothecenes (TCTCs), deoxynivalenol (DON)-related type B TCTCs (total DON), and zearalenone (ZE), respectively. A small portion (5.1%) of the samples was found to be contaminated with high levels ( > 1 microgram/g) of type A TCTCs and total DON during the whole survey. Over 40% of the samples had 100 to 1,000 ng of total DON per g, while 17% of the samples had the same levels of type A TCTCs. The analytical data were consistent with those from mycological examinations for the samples in which various toxic Fusarium spp., including F. sporotrichioides, F. poae, and F. graminearum, were found. The samples received in November 1992 had relatively low concentrations of toxin; the average levels of type A TCTCs and total DON were 9.9 and 79 ng/g, respectively. The toxin concentrations became progressively higher in the samples received in December. The average levels for the type A TCTCs and total DON increased to 920 and 335 ng/g, respectively. However, the levels of ZE were higher in the samples collected earlier. The average levels for samples collected in November and late December were 1,195 and 242 ng/g, respectively. Analysis of selected samples by high-performance liquid chromatography monitoring with an enzyme-linked immunosorbent assay revealed that T-2 toxin, HT-2 toxin, diacetoxyscirpenol, neosolaniol, and T-2 tetraol (T-2-4ol) were common in these samples. Statistical analysis revealed a weak correlation between the levels of total type A TCTCs and total DON in the samples (r = 0.18, P = 0.09), but a strong correlation between the levels of ZE and total type B TCTCs (r = 0.75, P < 0.0001) was found. The mycotoxin levels of total type A TCTCs, total DON-related type B TCTCs, and ZE in the cobs (5.2, 3.9, and 21 micrograms/g, respectively) were considerably higher than those in the kernels (1.0, 0.5, and 0.5 microgram/g, respectively). The type A toxin levels increased from a range of 14 to 35 ng/g to a range of 110 to 538 ng/g after the moldy corn samples were held at 5 degrees C for 8 days in the laboratory.

Food Microbiology↗

PubMed1998

Isolation and characterization of a dibenzofuran-degrading yeast: identification of oxidation and ring cleavage products.

We characterized the ability of a yeast to cleave the aromatic structure of the dioxin-like compound dibenzofuran. The yeast strain was isolated from a dioxin-contaminated soil sample and identified as Trichosporon mucoides. During incubation of glucose-pregrown cells with dibenzofuran, six major metabolites were detected by high-performance liquid chromatography. The formation of four different monohydroxylated dibenzofurans was proven by comparison of analytical data (gas chromatography-mass spectrometry) with that for authentic standards. Further oxidation produced 2, 3-dihydroxydibenzofuran and its ring cleavage product 2-(1-carboxy methylidene)-2,3-dihydrobenzo[b]furanylidene glycolic acid, which were characterized by mass spectrometry and 1H nuclear magnetic resonance spectroscopy. These two metabolites are derived from 2-hydroxydibenzofuran and 3-hydroxydibenzofuran, as shown by incubation experiments using these monohydroxylated dibenzofurans as substrates.

Benzofurans↗

PubMed1974

Comparison of the chemical structure and biological activities of the glycolipids of Salmonella minnesota R595 and Salmonella typhimurium SL1102.

It has been assumed in the past that the lipid moieties of endotoxic lipopolysaccharides are quite similar if not identical. This has been tested in the reported work here, where the chemical composition and biological activities of the glycolipids of two heptoseless Re mutants, Salmonella minnesota R595 and Salmonella typhimurium SL1102, have been studied and compared. The two glycolipids, extracted with chloroform-methanol (4:1), showed identical thin-layer chromatographic patterns. The molar ratios for hexosamine, fatty acids, phosphorus, 2-keto-3-deoxyoctonate, total amines, and total nitrogen of the purified glycolipids were in the same range, but small differences could be established. Both glycolipids contained the same major fatty acids, i.e., lauric, myristic, palmitic, and 3-hydroxymyristic acids, in similar but not identical ratios. On paper electrophoresis, the acid hydrolysates of the two glycolipids showed analogous components. In the determination of molecular weight, whereas S. minnesota R595 glycolipid did not show concentration dependence, the molecular weight measured for S. typhimurium SL1102 increased with its concentration. The molecular weight of the fully endotoxic R595 glycolipid has been found to be 17,000 +/- 1,500. Both glycolipids showed similar activities in the Shwartzman skin reaction, Limulus-lysate clotting assay, mouse lethality, and enhancement of nonspecific resistance, but the R595 preparation appeared to be more active on a weight basis in some parameters than SL1102. Using passive hemagglutination, we observed cross-reactivity between the glycolipids. In the gel-diffusion test, they revealed clear identity. The antiserum against S. minnesota R595 neutralized the Shwartzman skin reactivity not only of R595 but also of SL1102 glycolipid. These results confirm that there are identical immunodeterminant group(s) in the two glycolipids. On the other hand, chemical analytical data for two glycolipids showed only similarities, indicating that although both glycolipids are of comparable chemical nature, differences between them exist.

Antibodies, Bacterial↗

PubMed1975

Carotenoid pigments of facultatively anaerobic spirochetes.

Carotenoid pigments were purified from a previously undescribed, red, halophilic spirochete (spirochete RS1), and from Spirochaeta aurantia strain J1. Both spirochetes are facultative anaerobes and produce pigments when growing aerobically. The major pigments of the two spirochetes were identified by means of chromatographic analysis, absorption spectroscopy, hydride reduction, acetylation and silylation experiments, and mass spectrometry. It was concluded that the major pigment from spirochete RS1 was 4-keto-1',2'-dihydro-1'-hydroxytorulene. This conclusion was further supported by infrared spectroscopy and additional analytical data. The evidence showed that the major pigment from S. aurantia was 1',2'-dihydro-1'-hydroxytorulene. Chromatographic and spectrophotometric evidence indicated that this pigment was also present, as a minor carotenoid component, in spirochete RS1. These pigments have been previously detected almost exclusively in gliding bacteria, such as species of Flexibacter, Stigmatella, and Myxococcus. The occurrence of 4-keto-1',2'-dihydro-1'-hydroxytorulene and 1',2'-dihydro-1'-hydroxytorulene in both spirochetes and gliding bacteria may have significance with respect to the evolutionary development of these organisms.

Acetylation↗