Selective measurement of white matter and gray matter diffusion trace values in normal human brain

The trace of the diffusion tensor (or simply the trace) is diagnostically valuable for detecting acute ischemic lesions. A number of studies indicate that the trace of human gray matter (GM) and white matter (WM) are quite similar. This is somewhat surprising considering the different cellular environments of GM and WM. It is possible that partial volume averaging (PVA) effects between GM and WM, inherent in many of the ultrafast imaging sequences used for diffusion measurements, are responsible for this observation. In order to minimize PVA effects, the trace values of GM and WM have been selectively measured by implementing double inversion recovery (DIR) echo planar imaging (EPI) pulse sequences. Results on six normal volunteers indicate that the trace values of WM and GM are not statistically different.     

In search of human dignity: gender equity, reproductive health and healthy aging

This paper analyzes the nine pillars of human dignity (sufficient food, potable water, shelter, sanitation, health services, healthy environment, education, employment and personal security), which humankind tries to establish by following nine approaches to reality (scientific, cultural, religious, ethical, economical, ecological, socio-critical, philosophical and political) in a world drastically changed by nine revolutions (demographic, scientific, technological, communication, global identity, environmental, contraceptive, reproductive health and gender equity). The author's generation participated in these revolutions and contributed to the global intellectual process by which gender equity and reproductive health assumed a central role in world affairs. A rapidly aging world population constitutes another major challenge. Its likely impact on the very fundaments of our future social, economical, health and even political infrastructures is--as yet--incompletely comprehended by the international community. The International Federation of Gynecology and Obstetrics (FIGO) has and will continue to have an indispensable role in assisting humankind to reach its ultimate goal : human dignity.     

In vivo morphometry of the lamina cribrosa and its relation to visual field loss in glaucoma

Academic medical centers (i.e., teaching hospitals) and academic medical practices are under pressure to control costs to compete with for-profit health care institutions. The authors explain how academic physician managers who want to control costs wisely must first understand the cost structure of the medical center or practice and compare that structure with those of for-profit institutions. Doing this requires a firm understanding of how to use a valuable tool, financial statement analysis, to assess an institution's health and performance. Such analysis consists of calculating a variety of financial ratios (e.g., operating income divided by revenues; net income divided by total assets) and then comparing them with the corresponding ratios that are considered industry norms. Three types of financial statements (defined in detail) lend themselves to this approach: the balance sheet, income statement, and statement of cash flows. The authors define standard financial ratios, point out their uses and limitations, and emphasize that a ratio's meaning derives from comparing it with the corresponding benchmark ratio in the industry as a whole. Ratios should be used not as the end point of assessing financial status, but as ways to identify possible problems that require further investigation. Analysis of trends of ratios over time within an institution is a complementary approach. The authors then discuss the use of ratios in three standard types of institutional evaluation: of performance, of liquidity and leverage, and of strategic planning. In addition, they present the financial statement of a fictitious academic medical center as an example of how to use ratios for financial statement analysis. The authors emphasize that the key to using the ratios they discuss and hundreds of others is first to decide what question needs answering and then to choose the relevant ratios to provide a basis for finding the answer.     

Place and response learning in human virtual navigation: Behavioral measures and gender differences.

Two experiments examined the use of place and response strategies by humans navigating virtual multiple T mazes. In Experiment 1, probe trials revealed that participants commonly used place and response strategies, and place strategies were more frequent early in training, whereas response strategies were more frequent late in training. Compared with women, men learned the correct path through the maze more quickly and developed a more stable route through the maze. In Experiment 2, participants were trained to locate 2 targets. One target required participants to use either a place or response strategy, whereas the other target could be found using either strategy. Accuracy improved faster for place training compared with response training, and women outperformed men in both groups. Probe trials testing transfer of the imposed strategy to the other target found faster transfer for place training than for response training and that women demonstrated faster transfer than men. Accuracy on probe trials was correlated with poor route stability in the place-trained group and with good route stability in the response-trained group, indicating that navigation strategy use may be related to measures of improvement in performance on normal trials. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Localization of the central sulcus and adjacent sulci in human: a study by MRI

Variations in localization of the central sulcus and the sulci around the central sulcus namely the superior frontal sulcus, precentral sulcus, postcentral sulcus, marginal ramus of cingulate sulcus were studied in vertex sections retrospectively by magnetic resonance imaging (MRI) method in 3580 cases. Out of total number of cases, 1000 who did not show any macroscopic intracranial pathology were carefully selected for research. Additionally, 0-1 age group was excluded from the study because the sulci develop in first year of postnatal life, excluding the possibility of considering these as anatomical variations. Thus, the total number of cases is decreased to 990. 16 variations related to localization of the superior frontal sulcus, precentral sulcus, central sulcus, postcentral sulcus and the marginal ramus of the cingulate sulcus were identified. The asymmetries of the sulci, the most variable sulci and the distribution of the variations according to sex were statistically analysed.     

In vivo high resolution MRI of the calcaneus: differences in trabecular structure in osteoporosis patients

The purpose of this study was to use high resolution (HR) magnetic resonance (MR) images of the calcaneus to investigate the trabecular structure of patients with and without osteoporotic hip fractures and to compare these techniques with bone mineral density (BMD) in differentiating fracture and nonfracture patients. Axial and sagittal HR MR images of the calcaneus were obtained in 50 female (23 postmenopausal patients with osteoporotic hip fractures and 27 postmenopausal controls). A three-dimensional gradient-echo sequence was used with a slice thickness of 500 micron and in plane resolution of 195 x 195 micron. Texture analysis was performed using morphological features, analogous to standard histomorphometry and fractal dimension. Additionally, BMd measurements of the hip (dual-energy X-ray absorptiometry) were obtained in all patients. Significant differences between both patient groups were obtained using morphological parameters and fractal dimension as well as hip BMD (p < 0.05). Odds ratios for the texture parameters apparent (app.) bone volume/total volume and app. trabecular separation were higher than for hip BMD. Receiver operator characteristic values of texture measures and hip BMD were comparable. In conclusion, trabecular structure measures derived from HR MR images of the calcaneus can differentiate between postmenopausal women with and without osteoporotic hip fractures.     

Regional differences in electrophysiological properties of epicardium, midmyocardium, and endocardium. In vitro and in vivo correlations

BACKGROUND: Microelectrode studies have described a population of cells within the midmyocardium (M cells) displaying a steep rate dependence of action potential duration (APD) and high Vmax compared with endocardial (Endo) and epicardial (Epi) cells. METHODS AND RESULTS: We studied repolarization in different myocardial layers in vitro and in situ. In addition to confirming the results of earlier studies, we found that after abrupt lengthening of the cycle length (CL), APDs in M cells reached a new steady state faster than in Epi or Endo cells: the time to achieve 90% of the difference in APD (t90) was 13.3 +/- 0.7 minutes in Endo cells, 12.8 +/- 1.1 minutes in Epi cells, and 2.6 +/- 0.4 minutes in M cells (P < .05 compared with Epi or Endo) when CL changed from 400 to 1000 ms. In situ, we registered activation-recovery intervals (ARIs) in bipolar electrograms obtained from different myocardial layers in conditions of AV block and His-bundle pacing. At all CLs from 300 to 2000 ms, ARIs were equal in all myocardial layers from Epi to Endo cells. Steady-state ARIs coincided with APD of M cells registered in vitro in the physiological range of CL from 300 to 700 ms. When CL was changed from 300 to 1000 ms, the ARI followed the rapid time course typical of M cells (t90 = 2.6 +/- 0.5, 2.2 +/- 0.4, 2.5 +/- 0.4, 2.6 +/- 0.5, and 2.3 +/- 0.4 minutes for Epi; 3-, 5-, and 7-mm sub-Epi; and Endo cells, respectively). CONCLUSIONS: In contrast to in vitro results, there is no significant difference in repolarization among myocardial layers in the intact normal canine heart.     

Individual differences in lateralization: effects of gender and handedness

Representative genomes from each of the three kingdoms of life are compared in terms of protein structure, in particular, those of Haemophilus influenzae (a bacteria), Methanococcus jannaschii (an archaeon), and yeast (a eukaryote). The comparison is in the form of a census (or comprehensive accounting) of the relative occurrence of secondary and tertiary structures in the genomes, which particular emphasis on patterns of supersecondary structure. Comparison of secondary structure shows that the three genomes have nearly the same overall secondary-structure content, although they differ markedly in amino acid composition. Comparison of super-secondary structure, using a novel "frequent-words" approach, shows that yeast has a preponderance of consecutive strands (e.g. beta-beta-beta patterns), Haemophilus, consecutive helices (alpha-alpha-alpha), and Methanococcus, alternating helix-strand structures (beta-alpha-beta). Yeast also has significantly more helical membrane proteins than the other two genomes, with most of the differences concentrated in proteins containing two transmembrane segments. Comparison of tertiary structure (by sequence matching and domain-level clustering) highlights the substantial duplication in each genome (approximately 30% to 50%), with the degree of duplication following similar patterns in all three. Many sequence families are shared among the genomes, with the degree of overlap between any two genomes being roughly similar. In total, the three genomes contain 148 of the approximately 300 known protein folds. Forty-five of these 148 that are present in all three genomes are especially enriched in mixed super-secondary structures (alpha/beta). Moreover, the five most common of these 45 (the "top-5") have a remarkably similar super-secondary structure architecture, containing a central sheet of parallel strands with helices packed onto at least one face and beta-alpha-beta connections between adjacent strands. These most basic molecular parts, which, presumably, were present in the last common ancestor to the three Kingdoms, include the TIM-barrel, Rossmann, flavodoxin, thiamin-binding, and P-loop-hydrolase folds.     

More differences about gender differences in marriage: A reply to Beach, Davey, and Fincham (1999).

S. R. H. Beach, A. Davey, and F. D. Fincham (see record 1999-15264-018) suggest that my (L. A. Kurdek, 1998; see record 1998-11410-003) failure to replicate their finding that the prospective links between depressive symptoms and marital quality differ between husbands and wives was due, in part, to the selection of a time lag that was too long and a sample that was homogenous on risk factors. Accordingly, the author reexamined the prospective links between depressive symptoms and marital quality using only a 1-year time lag and an expanded sample (N?=?406) that included spouses in first marriages and remarriages with appreciable variability on depressive symptoms. There was still no evidence that husbands and wives differed in the pattern of these prospective links. The author also addresses concerns that the growth-curve analyses did not provide a good fit to the observed data, speculates about reasons for the differences in findings, and makes recommendations for future longitudinal work in this area. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Patterns of hemispheric perceptual asymmetries: Left hemispatial biases predict changes in anxiety and positive affect in undergraduate women.

Consistent with the tripartite model of anxiety and depression, hemispheric asymmetries may be differentially associated with depressive and anxious symptoms. Indeed, research has demonstrated that asymmetries do exist when examining hernispatial biases in both anxious and depressed individuals; however, the magnitude and direction of these asymmetries has been variable. The Chimeric Faces Task was used here to measure these asymmetries, along with measures for current and future levels of anxiety and depression. Results indicated that (a) increased left hemispatial biases at Time 1 predict increased anxiety (i,e., physiological hyperarousal) at Time 2 among 63 female undergraduate students (aged 18-47 yrs) and (b) decreased left hernispatial biases at Time 1 predict decreased positive affectivity at Time 2 among the same participants. The possibility that hemispatial biases represent a vulnerability to future anxiety and depression is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In vivo and ex vivo evaluation of the antithrombogenicity of human thrombomodulin immobilized biomaterials

Human thrombomodulin (hTM) is a newly described endothelial cell associated protein that functions as a potent natural anticoagulant by converting thrombin from a procoagulant protease to an anticoagulant. Focusing on the establishment of the practical evaluation of hTM immobilized materials, the activity of immobilized hTM was evaluated by in vivo and ex vivo blood contacting tests. As the basis for immobilization, regenerated cellulose films and hollow fibers were used. For the in vivo test, hTM immobilized cellular hollow fibers were implanted into dog blood vessels. Using hTM immobilized cellulose hollow fibers, a small scale dialyzer was assembled and its antithrombogenic activity was studied using human blood. As a result, it was revealed that the immobilized hTM still has co-enzymatic activity for activation of Protein C and anticoagulant activity. The coagulation time of the human blood passed through the hTM immobilized small dialyzer was effectively prolonged. It is expected that hTM immobilized cellulose should be a useful antithrombogenic biomaterial.     

Sex differences in mental abilities, hemispheric lateralization, and rate of physical growth at adolescence.

Tested the hypothesis that sex differences in verbal and spatial abilities are related to sex differences in rates of physical maturation and that this relationship is mediated by variation in the organization of higher cortical functions. 40 males and 40 females, ranging in age from 10-16 yrs, were tested on 3 verbal measures (including the Digit Symbol subtest of the WISC and the Word Fluency subtest of the Primary Mental Abilities Test), 3 spatial measures (including the Block Design subtest of the WISC and a modified version of the Embedded Figures Test), and a dichotic test of phoneme identification. Late-maturing Ss of both sexes performed better than early maturers on tests of spatial ability, but the groups did not differ on tests of verbal ability. Among older Ss, the late maturers of both sexes showed greater hemispheric lateralization than early maturers. Sex differences on the ability measures, although in the predicted direction, did not reach significance. Results are discussed with respect to the relationship between hemispheric organization of function and mental abilities and the relationship between maturational rate and lateralization. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In vivo versus in vitro produced bovine ova: similarities and differences relevant for practical application

1. Ortho-phenylphenol (OPP) was well absorbed in the male B6C3F1 mouse, with 84 and 98% of the administered radioactivity recovered in the 0-48-h urine of animals administered a single oral dose of 15 or 800 mg/kg respectively. High absorption and rapid elimination were also seen in the female and male F344 rat with 86 and 89% respectively of a single oral dose (27-28 mg/kg) found in the urine in 24 h. OPP was also rapidly eliminated from human volunteers following dermal exposure for 8 h (0.006 mg/kg), with 99% of the absorbed dose in the urine in 48 h. 2. Sulphation of OPP was found to be the major metabolic pathway at low doses in all three species, accounting for 57, 82 and 69% of the urinary radioactivity in the male mouse (15 mg/kg, p.o.), male rat (28 mg/kg, p.o.) and male human volunteers (0.006 mg/kg, dermal). OPP-glucuronide was also present in all species, representing 29, 7 and 4% of the total urinary metabolites in the low dose groups of mouse, rat and human volunteers respectively. 3. Conjugates of 2-phenylhydroquinone (PHQ) in these single-dose studies accounted for 12, 5 and 15% of the dose in mouse, rat and human, respectively. Little or no free OPP was found in any species. No free PHQ or PBQ was found in the mouse, rat or human (LOD = 0.1-0.6%). 4. A novel metabolite, the sulphate conjugate of 2,4'-dihydroxybiphenyl, was identified in rat and man, comprising 3 and 13% of the low dose respectively. 5. Dose-dependent shifts in metabolism were seen in the mouse for conjugation of parent OPP, indicating saturation of the sulphation pathway. Dose-dependent increases in total PHQ were also observed in mouse. 6. This study was initiated to elucidate a mechanistic basis for the difference in carcinogenic potential for OPP between rat and mouse. However, the minor differences seen in the metabolism of OPP in these two species do not appear to account for the differences in urinary bladder toxicity and tumour response between mouse and rat.     

Classification of behavior disorders in adolescence: Scaling methods, predictive validity, and gender differences.

The present study examined issues relating to the measurement and discriminant validity of Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic criteria for behavior disorders in adolescence (conduct disorder [CD], oppositional defiant disorder [ODD], attention-deficit/hyperactivity disorder [ADHD]). Data were obtained from a birth cohort of 995 New Zealand–born individuals studied to the age of 25 years and modeled associations between behavior disorder from ages 14 to 16 years and later outcomes including crime, substance use, mental health, parenthood and partnership outcomes, and education and employment outcomes to age 25 years. The associations between behavior disorders and outcomes were adjusted for both comorbid behavior disorders and a range of confounding factors. The results suggested that (a) dimensional measures of behavior disorder were more strongly correlated with outcomes than categorical (DSM) measures; (b) CD, ODD, and ADHD each had a distinctive pattern of associations with longer term consequences; and (c) there was no evidence to suggest that the developmental consequences of CD, ODD, and ADHD differed by gender. In general, the results supported the validity of DSM diagnostic domains but also highlighted the importance of including in DSM–V methods for both recognizing the severity of disorder and addressing subclinical symptom levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The incidence of dorsal sulci of the scapula in a modern human population from Ensay, Scotland

We have examined the binding of the local anaesthetic agent [3H]amethocaine to rat cerebrocortical membranes. All studies were performed in Tris buffer 50 mmol litre-1 at pH 7.4. Bound and free radioligand were separated by rapid vacuum filtration. [3H]Amethocaine binding at room temperature was dose-dependent and saturable, with mean Kd and Bmax values of 153 (SEM 18) nmol litre-1 and 9.4 (1.6) pmol/mg protein, respectively. [3H]Amethocaine binding was displaced in a dose-dependent manner (pIC50) by unlabelled amethocaine (6.89), procaine (5.20), lignocaine (3.46) and prilocaine (2.81). Ropivacaine and bupivacaine did not produce 50% displacement at the highest concentrations used (10(-4) and 10(-3) mol litre-1, respectively). We examined the nature of the binding site further with a range of ion channel antagonists (nifedipine, verapamil, diltiazem, omega-conotoxin, tetrodotoxin, tetraethylammonium and 4-aminopyridine) and ion channel coupled receptor ligands (L-glutamate, MK801, GABA, glycine and nicotine). With the exception of tetraethylammonium (pIC50 3.07) and 4-aminopyridine (pIC50 3.68), all non-anaesthetic agents failed to displace [3H]amethocaine. Collectively our data suggest that it is unlikely that there is a single target site for all local anaesthetic agents.     

A calculation of the forces acting on the human acetabulum during walking. Based On in vivo force measurements, kinematic analysis and morphometry

Information about the loading of the human acetabulum during walking is necessary for a functional understanding of the morphology of the pelvic girdle and the hip joint as well as for the optimization of endoprosthetic therapy in osteoarthritis. For this purpose, experimental data of the forces acting on the femur in walking taken from the literature [Bergmann et al.: J. Biomech. 1993;26: 969-990] were combined with our own kinematic and morphometric data, to transform the force vectors from the femoral into a pelvic and an acetabular frame. During the walking cycle, the resultant force vector takes a rather constant course relative to the pelvis and its orientation seems to be highly regulated to act within a small range of angles. Only small deviations occur from the angles against the vertical which the resultant peak force forms in the frontal plane (F = 11 degrees, medially orientated) and in the sagittal plane (S = 5 degrees, ventrally orientated). The experimental results form the basis for a model of the incongruous hip joint as an elastic joint, the femoral head being centered between compliant elements.     

Conditional stimulus probability and activity of hippocampal, cingulate cortical, and limbic thalamic neurons during avoidance conditioning in rabbits.

Multi-unit and field potential responses in the anterior (AC) and posterior cingulate cortices (PC), dentate gyrus (DG), and anterior ventral (AV) and medial dorsal (MD) thalamic nuclei of rabbits were recorded during acquisition and performance of a locomotor conditioned response (CR). The CR, stepping in an activity wheel in response to a tone (conditioned stimulus [CS+]), prevented the occurrence of a shock unconditioned stimulus (UCS) scheduled 5 sec after CS+ onset. Ss also learned to ignore a different tone (CS–), not predictive of the UCS. Training was given daily until behavioral discrimination reached criterion. After criterion, asymmetric probability (AP) sessions were given that were the same as the conditioning session except for probability manipulation. A significant discriminative response developed in all regions during behavioral acquisition. The unit response in the AP session was enhanced in all areas by rare presentation of the CS–, compared with the equal and frequent CS– conditions. Rare presentation of the CS+ enhanced the unit response in the AC, PC, and DG, but it suppressed the firing of AV and MD neurons. Rare CS+ presentations did not alter AV and PC neuronal activity in Ss with subicular lesions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In vivo and in vitro studies of 15alpha-hydroxyprogesterone in the human placenta

Studies were conducted to determine the fate of 15alpha-hydroxyprogesterone in human placental tissue. Tritiated 15alpha-hydroxyprogesterone was perfused through normal human placentas in situ at the time of Cesarean section and incubated with a 10,000x g microsomal supernate of the placenta in vitro. In both systems the substrate, but no additional metabolites were identified. These findings indicate that 15alpha-hydroxyprogesterone is not metabolized during its passage in the human term placenta, and suggests that because of its fetal origin clinical measurements of 15alpha-hydroxyprogesterone may provide a valuable index to the status of fetal viability.     

Influence of hemispheric specialization in sensory processing on reaching in infants: Age and gender related effects.

Music or speech were presented separately to the right or left ears of 48 6- and 8-mo-old infants as they reached for an object. Examination of the latency to contact the object revealed a complex relationship between type of auditory input and locus of presentation as a function of age and gender. In younger males, presentation of speech to the left ear resulted in longer contact latencies than did presentation of music. Younger females showed no asymmetries. Older males took significantly longer to contact when music was presented to their right than to their left ear; older females exhibited a tendency toward the typical adult pattern of specialization in that there was a greater effect of speech at their right than at their left ear, and vice versa for music. Data are discussed in terms of possible sequences in the development of hemispheric specialization. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)