Measurement of peripheral tissue thickness by ultrasound during the perioperative period.
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We have studied changes in peripheral tissue thickness with a novel hand-held ultrasound device during the perioperative course of 60 healthy surgical patients in three different intraoperative body positions. The nil-by-mouth period led to a significant decrease in forehead tissue thickness. Standardized infusion therapy with Ringer's solution at a rate of 8 ml kg-1 h-1 resulted in a gradual increase in tissue thickness, which was significantly different from preoperative baseline values after 90 min. Packed cell volume decreased significantly after the start of infusion and remained low over the rest of the observation time. Different body positions did not influence changes in tissue thickness. We conclude that changes in perioperative tissue thickness in healthy patients can be detected easily by ultrasound, independent of body position. This method may prove useful for the non-invasive assessment of fluid balance state. (+info)
Odor distinctiveness between enantiomers of linalool: difference in perception and responses elicited by sensory test and forehead surface potential wave measurement.
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The effects on humans of inhalation of optically active linalools were examined in terms of sensory tests and portable forehead surface electroencephalographic (IBVA-EEG) measurements in order to assess their odor distinctiveness by chiral isomers. (R)-(-)-Linalools with specific rotation of [alpha](D) = -15.1 degrees were isolated by repeated flash column chromatography from lavender oil, while (S)-(+)-linalools with [alpha](D) = +17.4 degrees and (RS)-(+/-)-linalools with [alpha](D) = 0 degrees and content of (R)-form 50.9% and (S)-form 49.1% were obtained from coriander oil and commercial linalool, respectively, by using the same method. With the use of an inhalator, each was administered to subjects both before and after 10 min of work. It was found that administration after work evoked different subjective impressions when compared with that before work depending on the configuration of the isomers and the type of work employed. For instance, inhalation of (R)-(-)-linalool after hearing environmental sounds not only produced a much more favorable impression in the sensory test but was also accompanied by a greater decrease in beta waves after work in comparison with that before work. This is in contrast to the case of mental work, which resulted in a tendency for agitation accompanied by an increase in beta waves. These findings led us to conclude that enantiomeric stereospecificity of linalool evoked different odor perception and responses not only with chiral dependence but also with task dependence. In addition, in comparing these sensory profiling features and IBVA-EEG tendencies between hearing environmental sound and mental work, a tendency was observed for (R)-(-)-linalool to coincide with (RS)-(+/-)-linalool but not with (S)-(+)-linalool. (+info)
A comparison of chincap and maxillary protraction appliances in the treatment of skeletal Class III malocclusions.
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The purpose of this retrospective investigation was to compare cephalometrically the treatment effects of chincap and maxillary protraction appliances in subjects with a Class III skeletal malocclusion with a combination of an underdeveloped maxilla and prominent mandible. Twenty-four patients were divided into two groups according to the treatment type; the chincap group (mean age 11.03 years, n = 12) and the Delaire type maxillary protraction appliance group (mean age 10.72 years, n = 12). In both groups, a significant increase in ANB, molar relationship, and overjet showed the effect of the appliances in the treatment of Class III malocclusions. In comparing the two groups, the maxilla was displaced more anteriorly and the molar relationship correction was greater in the maxillary protraction appliance group (P < 0.05). Angular and dimensional parameters for lower incisor/NB and nasolabial angle showed significant differences between the groups (P < 0.05). (+info)
Non-invasive raman spectroscopic detection of carotenoids in human skin.
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Carotenoids are thought to play a significant part in the skin's anti-oxidant defense system, and may help prevent malignancy. Inability to measure skin carotenoid content readily has, however, made it difficult to establish the relationship between carotenoid concentration and the occurrence of cutaneous malignancy. We have measured in vivo carotenoid concentration using a noninvasive optical method, Raman spectroscopy. To validate our instrumentation, abdominoplasty skin was evaluated by both Raman spectroscopy and high-performance liquid chromatography determination for carotenoid content. Evaluation of the Raman signal in specific carotenoid solutions was also performed. Precision of Raman measurements within skin sites, within subjects, and between subjects was measured. Sensitivity of the method was evaluated as a function of anatomical region and the distribution of carotenoids within the stratum corneum. Lastly, we evaluated the Raman signal in actinic keratosis and basal cell carcinoma lesions and perilesional skin and compared this with region-matched sites in healthy subjects. Our results indicate that the Raman scattering method reflects the presence of carotenoids in human skin and is highly reproducible. Evaluation of five anatomical regions demonstrated significant differences in carotenoid concentration by body region with the highest carotenoid concentration noted in the palm. Comparison of carotenoid concentrations in basal cell carcinomas, actinic keratosis, and their perilesional skin demonstrate a significantly lower carotenoid concentration than in region-matched skin of healthy subjects. These results represent the first evidence that carotenoid concentration in the skin correlate with the presence or absence of skin cancer and precancerous lesions. (+info)
Dietary carotenoids contribute to normal human skin color and UV photosensitivity.
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The aim of the current study was to determine whether dietary carotenoids influence skin pigmentation and UV photosensitivity in a healthy unsupplemented panel (n = 22) of Caucasian (skin Type II) subjects. Skin spectrophotometric and tristimulus (L*a*b*) CR200 chromameter readings were made at various body sites to objectively measure skin carotenoid levels and skin color, respectively. The minimal erythemal dose (MED) was also measured to determine the intrinsic UV photosensitivity of the skin. We found that tristimulus b* values (but not L* and a* values) were consistently and closely correlated with skin carotenoid levels at a number of body sites including the back (r = 0.85, P < 0.00001), forehead (r = 0.85, P < 0.00001), inner forearm (r = 0.75, P < 0.0001) and palm of the hand (r = 0.78, P < 0.0001). Skin carotenoid levels and MED were also correlated in these subjects (r = 0.66, P < 0.001), as were tristimulus b* values and MED (r = 0.71, P < 0.0002). From these observations, we conclude that carotenoids from a normal, unsupplemented diet accumulate in the skin and confer a measurable photoprotective benefit (at least in lightly pigmented Caucasian skin), that is directly linked to their concentration in the tissue. Carotenoids also appear to contribute measurably and significantly to normal human skin color, in particular the appearance of "yellowness" as defined objectively by CR200 tristimulus b* values. On the basis of these findings we believe that objective measurements of skin color, in particular tristimulus b* values, may be a potentially useful means of monitoring dietary carotenoid status and assessing UV photosensitivity in Caucasian populations. (+info)
The influence of different facial components on facial aesthetics.
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Facial aesthetics have an important influence on social behaviour and perception in our society. The purpose of the present study was to evaluate the effect of facial symmetry and inter-ocular distance on the assessment of facial aesthetics, factors that are often suggested as major contributors to facial aesthetics. The material consisted of 36 standardized facial photographs of patients (10-17 years of age) attending the orthodontic department. All except one were Caucasian. Eleven of these photographs (all Caucasian) were either left in their original form or modified by: (1) enlargement of the inter-ocular distance by 20 per cent; or (2) mirroring the right part of the face over the left part to obtain symmetry. Three series of 36 slides were composed, each including 11 modified slides or their unmodified counterparts. These were evenly distributed over the three series using a Latin square design. The photographs were assessed for their facial aesthetics using a visual ratio scale by a panel of 50 undergraduate dental and law students. The 11 modified/unmodified photographs enabled calculation of the effect of the modifications undertaken on the assessment of facial aesthetics. The scores of the 25 remaining photographs in each series were used as baseline data in order to estimate the inter- and intra-observer reproducibility. MANOVA and post-hoc t-test revealed significant differences between the unmodified and modified photographs (P < 0.001). The results show that symmetry and inter-ocular distance enlargement have a negative effect on facial aesthetics. (+info)
The OxiMax System. Nellcor's new platform for pulse oximetry.
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The new OxiMax Pulse Oximetry System includes the Nellcor N-595 Pulse Oximeter and a new line of OxiMax sensor. The main feature of this platform is the digital memory chip inserted within each OxiMax sensor that contains all the calibration and operating characteristics for that individual sensor. It allows an information exchange between the sensor and the monitor improving monitoring performance during difficult acquisition periods. We reviewed several studies showing that the more centrally placed forehead sensor can offer significant advantage over finger sensor when monitoring patient with low pulse perfusion, especially in situation where rapid detection of hypoxemia is critical. (+info)
Different patterns of parasympathetic activation in uni- and bilateral migraineurs.
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Several lines of evidence support involvement of the parasympathetic system in migraine: (i) migraine-associated symptoms, such as exaggerated facial flushing, lacrimation and rhinorrhea; (ii) increased levels of cranial venous vasoactive intestinal peptide in migraineurs during attacks; and (iii) reports of migraine pain alleviation by intranasal instillation of lidocaine, which can block some of the parasympathetic outflow to the cranium. This study assessed cranial parasympathetic function in migraineurs in between attacks, assuming that abnormal function might imply involvement of the parasympathetics in migraine pathogenesis. We tested 39 female migraineurs outside attacks, of whom 11 had bilateral pain, 20 unilateral at a specific side and eight alternating unilateral head pain, and 16 controls. The trigemino-parasympathetic reflex was studied, using soapy and saline eye drops for stimulation of the afferent limb of the reflex arch, and cutaneous vascular response at the forehead for the efferent limb. The latter was recorded by photoplethysmography on both sides of the forehead. We found no difference in vasodilatation between migraineurs as a group and controls (83.7 +/- 6.5% and 80.8 +/- 7.6%, respectively, not significant). However, when analysing data by the site of pain, we found that those with bilateral pain had the largest vasodilatation response (141.6 +/- 16.2%, P < 0.05 versus controls, analysis of varance, post hoc Tukey-Kramer HSD), while those with unilateral pain had the least vasodilatation (45.5 +/- 3.3%, P < 0.05). The response of patients with alternating pain (97.2 +/- 12.6%) did not differ from controls. It is concluded that cranial parasympathetic function does differ among patients with various migraine types at rest. Based on the understanding of dysfunctional brainstem pain modulation in migraine, we suggest a model of within-brainstem interaction between the two locus coeruleus nuclei, which are involved in control of pain and cranial parasympathetic outflow. The model assumes various levels of inhibitory inter-relationships between these two nuclei; diminution or absence of the normal reciprocal inhibitory relationships between them may underlie the augmented cranial parasympathetic response in bilateral migraineurs, while an excess of reciprocal inhibitory relationship between them may underlie the diminished cranial parasympathetic response in unilateral migraineurs. These findings might help in clarifying inter-relationships between brainstem nuclei in the context of migraine pathogenesis. (+info)