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Although neuroblastoma is a common childhood malignancy, which frequently metastasizes, involvement of the facial bones and paranasal sinuses are uncommonly reported in the literature. However, over the last several years, we have encountered an increasing number of cases of metastatic neuroblastoma to the central nervous system and head and neck. This article will review the common and uncommon imaging manifestations of metastatic neuroblastoma, with emphasis on the orbits, maxillofacial bones, and paranasal sinuses.

Objective: Although neuroblastoma is a common childhood malignancy, which frequently metastasizes, involvement of the CNS is rarely reported in the literature. However, over the past several years, we have encountered an increasing number of cases of metastatic neuroblastoma to the CNS. This metastatic potential and changing metastatic pattern may, in part, be due to advances in medical treatment, leading to prolonged survival. This article will review the common and uncommon manifestations of metastatic neuroblastoma with an emphasis on the skull, dura, brain, ventricles, and leptomeninges., Conclusion: Neuroblastoma has diverse manifestations including masquerading as primary neurologic disease. This disease must be considered in a child with any unexplained neurologic disorder. Realizing that neuroblastoma may represent the cause of neurologic disease in a child will lead to earlier diagnosis.

Non-photochemical quenching (NPQ) is a complex and still unclear mechanism essential for higher plants. The intensive research on this subject has highlighted three main components of NPQ: energy-dependent process (qE); state transitions to balance the excitation of PSII and PSI (qT); and photoinhibitory processes (qI). Recently, these components have been resolved as quantum yields according to the energy partitioning approach that takes into account the rate constants of every process involved in the quenching mechanisms of excited chlorophylls. In this study a fully extended quantum yield approach and the introduction of novel equations to assess the yields of each NPQ component are presented. Furthermore, a complete analysis of the yield of NPQ in Beta vulgaris exposed to different irradiances has been carried out. In agreement with experimental results here it is shown that the previous approach may amplify the yield of qE component and flatten the quantitative results of fluorescence analysis. Moreover, the significance of taking into account the physiological variability of NPQ for a correct assessment of energy partitioning is demonstrated.

Objective: The purpose of this study was to review the craniofacial and intracranial clinical and radiologic manifestations of patients diagnosed with Langerhans cell histiocytosis (LCH). This report will compare the frequency of the various manifestations found in our series with those reported in the medical literature., Conclusion: In LCH, involvement of the calvaria, skull base, maxillofacial bones, and hypothalamic-pituitary axis is fairly common. The precise location of these lesions contributes to the variety of clinical manifestations of LCH, which includes scalp and/or facial swelling, seizures, hearing loss, recurrent otitis media, gingival bleeding, proptosis, diabetes insipidus, and cranial nerve palsies.

Background: The accurate measurement of total body water (TBW) requires isotopic dilution techniques that are not easily applicable to the clinical setting. Therefore, indirect methods of estimating TBW are commonly employed, such as bioelectrical impedance analysis (BIA) and anthropometry. In the human body, >90% of the measured impedance is composed of resistance (R)., Methods: The aim of the present study was to compare TBW estimated by means of two anthropometric equations (by Watson and Hume) with TBW obtained by BIA (equations proposed by Sun et al.) in a group of white disease-free individuals (n = 3625, 1860 men and 1765 women) and white haemodialysis (HD) patients (n = 688, 443 men and 245 women). They underwent one single-frequency BIA measurement, on the nondominant side of the body, injecting an 800-muA and 50-kHz alternating sinusoidal current with a standard tetrapolar technique. The BIA variable measured was R., Results: Among them, a selection of disease-free individuals (n = 481) and HD patients (n = 270), pair-matched by age, body weight and height, after stratification by gender, was made. When comparing the four pair-matched groups, it was found that (1) TBW was not different (disease-free men versus HD men; disease-free women versus HD women) when using anthropometric equations, which utilize quite identical parameters (age, body weight and height); (2) R was statistically significantly different in the four groups (511 +/- 58 SD Omega in disease-free men versus 558 +/- 80 in HD men, P < 0.0001; 593 +/- 70 Omega in disease-free women versus 615 +/- 100 in HD women, P < 0.02) and (3) therefore, TBW was statistically significantly different only when applying BIA equations (P < 0.0001 and 0.05, respectively)., Conclusions: The present study demonstrates that anthropometric equations for the estimation of TBW can be used only within a specific population in order to assess individual differences; they cannot be used in order to compare two different populations.

Background: Accurate assessment of hydration status and specification of dry weight (DW) are major problems in the clinical treatment of hemodialysis (HD) patients. Bioelectrical impedance analysis (BIA) has been recognized as a noninvasive and simple technique for the determination of DW in HD patients., Design, Setting, Participants, and Measurements: This study was designed to develop and validate BIA prediction equations for DW in HD patients. It included white adults (1540 disease-free adults with normal body mass index [BMI] and 456 prevalent and 27 incident HD patients). All participants underwent at least one single-frequency BIA measurement (800 muA and 50 kHz alternating sinusoidal current with a standard tetrapolar technique). The BIA variable measured was resistance (R). Data of 1463 (95% of the cohort) disease-free individuals with normal BMI (prediction sample) were used to establish best-fitting BIA prediction equations of body weight. The latter were cross-validated in the residual 5% subset (77 individuals) of the same cohort (validation sample)., Results: Multiple regression analysis showed a significant relationship among body weight, R, age, and height in 739 men (R(2) = 0.82, P < 0.0001) and among body weight, R, and height in 724 women (R(2) = 0.68, P < 0.0001) in the prediction sample. The Bland Altman analysis showed a mean difference between predicted and measured body weight of 0.3 +/- 1.0 kg (95% confidence interval +/- 2.0 kg) in the validation sample. The BIA prediction equations that were obtained in disease-free individuals with normal BMI were applied to a cohort of 456 prevalent HD patients: The mean difference between achieved and estimated DW was 0.1 +/- 1.0 kg (P = 0.53) in men and -0.3 +/- 1.0 (P = 0.76) in women. Finally, BIA prediction equations were tested in a cohort of 27 incident HD patients. The mean difference between predicted and achieved DW was -0.6 +/- 1.0 kg (P = 0.76) in men and 0.6 +/- 1.0 (P = 0.50) in women., Conclusions: This study was able to develop and validate BIA prediction equations for DW in HD patients. They seem to be a promising tool; however, they still need external validation.

Objective: Our objective was to describe the CT features of spontaneous isolated celiac artery dissection in a series of six otherwise healthy patients with acute abdominal pain., Conclusion: Although once believed rare, isolated spontaneous celiac artery dissection should be considered in the diagnosis of acute abdominal pain, especially in middle-aged adults.

A new sensitive and reproducible method was used to assess LDL oxidative status in Type 2 diabetic patients and control subjects, and the relationships between LDL oxidation and atherosclerosis or nephropathy were determined. LDL oxidation was measured in 35 patients with Type 2 diabetes and 15 control subjects 40 to 60 years of age. Atherosclerosis was assessed by clinical examination, vascular ultrasound, and measurement of intima-media thickness (IMT). Twenty-four hour urinary albumin excretion measurements were performed. Although no differences in lipid values were found between the 22 diabetic patients with atherosclerosis (ATS+) and the 13 without (ATS-), LDL oxidation was significantly higher in ATS+ than ATS- patients (p = 0.009) or control subjects (p = 0.007). LDL oxidation was also increased in the 15 patients with nephropathy (p = 0.003). Oxidation was correlated with IMT in patients with normal to moderately increased IMT ( < or = 1.05 mm). Determination of LDL oxidative status could thus be very helpful in assessing cardiovascular risk, especially in high-risk subjects such as patients with diabetes mellitus.

The authors examined students' perceptions, attitudes, and experiences of sexual harassment by faculty members at a state university, using a sample of 1,139 graduate and undergraduate students. Twenty-six percent (292) of those in the sample responded. The instrument used in the study, adapted from a survey previously used at the University of Iowa, operationally defined eight categories of behavior: sexist comments, undue attention, verbal sexual advances, body language, invitations, physical advances, explicit sexual propositions, and sexual bribery. As many as 8% of the respondents indicated they had experienced the three most extreme forms of harassment--physical advances, explicit sexual propositions, and sexual bribery. Although most students thought they would report sexual harassment, only three incidents of the most extreme forms of sexual harassment were actually reported. Those who experienced harassment indicated that it generally came from one rather than from several faculty members and that it came from both male and female faculty. Twenty-three percent of the men reported experiencing sexist comments, and 5 male students reported they had experienced at least one of the three most extreme forms of sexual harassment. Recommendations for policy revisions and campus health promotion programming that were made following the survey are discussed.

The chlorophyll content and the fluorescence induction kinetics at two wavelengths (690 nm and 735 nm) have been measured in leaves of nine common broadleaf tree species during the autumnal chlorophyll breakdown. The ratio of the chlorophyll fluorescence maxima F690/F735 was determined at fluorescence maximum (fm) and at steady-state conditions (fs) by the laser-induced fluorescence emission using the two-wavelength fluorometer. The ratio F690/F735 increases with the leaf discolouring during the autumnal chlorophyll breakdown. The relationship between the chlorophyll content and the ratio F690/F735 can be expressed by a power function (curvilinear relationship) which is valid for all the species examined. In most cases the ratio F690/F735 measured in the upper leaf side is lower than that in the lower leaf side, but the trend is the same along the decreasing chlorophyll content. The ratio F690/F735 is always higher at maximum fluorescence than at steady-state fluorescence in the upper as well as lower leaf side and these values are well fitted in a linear correlation. This study confirms the usefulness of the ratio F690/F735 as a suitable non-destructive indicator of the in-vivo chlorophyll content, especially at medium and low chlorophyll content.

We investigated several photosynthetic parameters of a virescent mutant of durum wheat and of its wild-type. Electron transport rate to ferricyanide was the same in the two genotypes when expressed on leaf area basis while O2 evolution of the leaf tissue in saturating light and CO2 was slightly higher in the yellow genotype. RuBPCase was also slightly higher. Quantum yield per absorbed light was similar in the two genotypes. P700 and Cyt f were less concentrated in the mutant while PS II was only marginally lower. The light response curve of CO2 assimilation indicated higher level of photosynthesis of the mutant in high light, which corresponded to a lower non-photochemical quenching compared to the wild-type. It is concluded that the reaction centres, cyt f and chlorophyll are not limiting factors of electron transport in wheat seedlings and that electron transport capacity is in excess with respect to that needed for driving photosynthesis. Since the differences in photosynthesis reflect differences in RuBPCase activity, it is suggested that this enzyme limits photosynthesis in wheat seedlings also at high light intensities.