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Notes: A family is described in which the propositus and her compatible sister have the Rh genotype -D/—. The — haplotype is inherited from the paternal side and the -D- haplotype from the maternal side of the family.

Notes: Purpose To determine if using CIE L*a*b* color measurements of white facial skin could be correlated to those of silicone shade samples that visually matched the skin. Secondly, to see if a correlation in color measurements could be achieved between the silicone shade samples and duplicated silicone samples made using a shade-guide color formula.Materials and Methods A color booth was designed according to ASTM specifications, and painted using a Munsell Value 8 gray. A Minolta colorimeter was used to make facial skin measurements on 15 white adults. The skin color was duplicated using custom-shaded silicone samples. A 7-step wedge silicone shade guide was then fabricated, representing the commonly encountered thicknesses when fabricating facial prostheses. The silicone samples were then measured with the Minolta colorimeter. The readings were compared with the previous L*a*b* readings from the corresponding patient's skin measurements, and the relative color difference was then calculated. Silicone samples were fabricated and analyzed for three of the patients to determine if duplication of the visually matched silicone specimen was possible using the silicone color formula, and if the duplicates were visually and colorimetrically equivalent to each other. The color difference Delta E and chromaticity was calculated, and the data were analyzed using a coefficient-of-variation formula expressed by percent. A Pearson Product Moment Correlation Coefficient was performed to determine if a correlation existed between the skin and the silicone samples at the p〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:1059941X:JOPR237:les" location="les.gif"/〉 .05 level.Results The highest correlation was found in the b* dimension for silicone thicknesses of 1 to 4 mm. For silicone thicknesses of 6 to 10 mm, the highest correlation was found in the L* dimension. All three dimensions had positive correlations (R2 〉 0), but only the 1-mm and 4-mm b* readings were very strong. Patient and silicone L*a*b* measurement results showed very little change in the a* axis, while the L* and b* measurements showed more change in their numbers, with changes in depth for all patient silicone samples. Delta E numbers indicated the lowest Delta E at the 1-mm depth and the highest Delta E at the 10-mm depth. All duplicated samples matched their original silicone samples to a degree that visual evaluation could not distinguish any color differences. Using volumetric measurements, a shade guide was developed for all 15 patients.Conclusions There was good correlation between the patient's colorimeter measurements and the silicone samples, with the b* color dimension the most reproducible, followed by the L* and the a*. Silicone samples at 6, 8, and 10 mm matched the patient the best, and this study showed that silicone samples can be duplicated successfully if a good patient-silicone match is obtained. Rayon flocking fibers and liquid makeup are effective at matching facial prostheses and can be used to develop a simple shade guide for patient application.

Notes: Purpose The hardness, porosity, and adaptation of removable partial dentures fabricated with one heat-polymerized denture base resin and two resins designed for microwave polymerization were evaluated.Materials and Methods Five prostheses were evaluated for each resin. Adaptation of the denture bases to the master cast was evaluated by spatial orientation and mean weight of residual impression material. The prostheses were then embedded in epoxy resin and sectioned for evaluation of resin hardness (Knoop hardness) and microporosity.Results There were no significant differences in the adaptation of the acrylic resin bases for Acron MC and Ch Lucitone. There was no significant difference in the mean Knoop hardness values for any of the resin bases near and away from the metal. None of the denture bases showed porosity greater than 100 μm.Conclusions Both resin bases formulated for microwave polymerization were effectively polymerized around metal frameworks without adverse effects on resin hardness or porosity. Justi Denture Base material had poorer base adaptation than the other two resins.

Notes: Serum biochemical profiles were compared in matched groups of premenopausal and postmenopausal women. Significantly higher concentrations of sodium, urea, calcium, albumin and alkaline phosphatase were found in the postmenopausal group. In the postmenopausal group, following treatment with sequential mestranol and norethisterone, significant reductions were recorded in the concentrations of sodium, urea, calcium, albumin, alkaline phosphatase and glucose and significant increases were recorded in the concentration of globulin and in body weight. The findings suggest that haemoconcentration may take place after the menopause and that this effect may be modified by hormone treatment. No adverse effect on liver function was noted following the hormone treatment.

Notes: The serum cholesterol and triglyceride concentrations of 84 postmenopausal women both before and after 2, 6 and 12 months therapy with various regimens of hormone therapy were measured. There was little alteration in mean serum cholesterol concentration with cyclical oestrogens but both sequential mestranol and norethisterone and sequential oestradiol valerate and norgestrel significantly reduced the mean serum cholesterol concentration to a level similar to that found in age-matched premenopausal women. There was a small and sometimes significant rise in serum triglyceride concentration with cyclical oestrogens. Sequential mestranol and norethisterone significantly elevated serum triglyceride levels, but sequential oestradiol valerate and norgestrel significantly depressed them. The results suggest that the progestogenic agent norgestrel has an important role to play in reducing both serum cholesterol and triglyceride levels, and that the sequential preparations, by virtue of their greater cholesterol lowering effect, should perhaps be preferred to cyclical oestrogens.

Notes: Hamamelitol is an unusual branched-chain sugar alcohol previously suggested to function as a leaf compatible solute. In this study, we have examined the leaf metabolism and intracelluiar compartmentalization of hamamelitol and other soluble sugars during long-term water stress treatment of Hedera helix (English ivy). Total leaf hamamelitol content was relatively low in greenhouse control plants, but increased 2-fold during water stress treatment to levels approaching those observed in field-grown plants (6–7 μmol g−1 fresh weight). Using density gradient fractionation with non-aqueous solvents, we showed that hamamelitol occurs primarily in the cytoplasm and vacuoles of leaf mesophyll cells. During water stress treatment most of the increase in leaf hamamelitol occurred in the mesophyll cytoplasm, compensating osmotically for a decrease in cytoplasmic sucrose concentration. The maximum concentration of cytoplasmic hamamelitol was 155 mol m−3 and occurred in field-grown plants. Labelling experiments showed that hamamelitol is slowly synthesized from 14CO2 in leaves of H. helix, but is very long-lived (estimated t1/2 of 4 years). Together, these data indicate that hamamelitol probably functions during long-term stress conditions as an osmotically active, compatible solute in plant leaves. We suggest that the signal for enhanced accumulation of hamamelitol during the water stress treatment was initiated by decreased plant growth and increased leaf sucrose hydrolysis.

Notes: Photosynthetic acclimation to elevated CO2 cannot presently be predicted due to our limited understanding of the molecular mechanisms and metabolic signals that regulate photosynthetic gene expression. We have examined acclimation by comparing changes in the leaf content of RuBP carboxylase/oxygenase (Rubisco) with changes in the transcripts of Rubisco subunit genes and with leaf carbohydrate metabolism. When grown at 1000 mm3 dm–3 CO2, 12 of 16 crop species at peak vegetative growth had a 15–44% decrease in leaf Rubisco protein, but with no specific association with changes in transcript levels measured at midday. Species with only modest reductions in Rubisco content (10–20%) often had a large reduction in Rubisco small subunit gene mRNAs (〉 30%), with no reduction in large subunit gene mRNAs. However, species with a very large reduction in Rubisco content generally had only small reductions in transcript mRNAs. Photosynthetic acclimation also was not specifically associated with a change in the level of any particular carbohydrate measured at midday. However, a threshold relationship was found between the reduction in Rubisco content at high CO2 and absolute levels of soluble acid invertase activity measured in plants grown at ambient or high CO2. This relationship was valid for 15 of the 16 species examined. There also occurred a similar, albeit less robust, threshold relationship between the leaf hexose/sucrose ratio at high CO2 and a reduced photosynthetic capacity ≥ 20%. These data indicate that carbohydrate repression of photosynthetic gene expression at elevated CO2 may involve leaf sucrose cycling through acid invertase and hexokinase.

Notes: 
 A max, maximum CO2 assimilation rate
CAB, genes encoding chlorophyll a/b binding proteins
Ci, intercellular CO2 concentration
PGK, the gene encoding 3-phosphoglycerate kinase
PRK, the gene encoding phosphoribulokinase
PSAB, the gene encoding the 83 kDa apoprotein of the PSI reaction centre
PSBA, the gene encoding the D1 protein of photosystem II
RBCS, genes encoding the Rubisco small subunit protein
RBCL, the gene encoding the Rubisco large subunit protein
Rubisco, ribulose-1,5-bisphosphate carboxylase/ oxygenase
SBP, the gene encoding sedoheptulose-1,5-bisphosphatase

There have been many recent exciting advances in our understanding of the cellular processes that underlie photosynthetic acclimation to rising atmospheric CO2 concentration. Of particular interest have been the molecular processes that modulate photosynthetic gene expression in response to elevated CO2 and the biochemical processes that link changes in atmospheric CO2 concentration to the production of a metabolic signal. Central to this acclimation response is a reduction in ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) protein content. Studies indicate that this reduction results from species-dependent variation in the differential use and temporal control of molecular processes. We present a model for the control of Rubisco protein accumulation that emphasizes the role of subunit message translation as well as the abundance of subunit messages as components of the acclimation response. Many studies indicate that photosynthetic acclimation to elevated CO2 results from adjustments in leaf carbohydrate signalling. The repression of photosynthetic gene expression is considered to occur primarily by hexokinase functioning as a hexose flux sensor that ultimately affects transcription. Leaf hexoses may be produced as potential sources of signals primarily by sucrose cycling and secondarily by starch hydrolysis. An increased rate of sucrose cycling is suggested to occur at elevated CO2 by enhanced provision of sucrose to leaf acid invertases. Additionally, sink limitations that accentuate photosynthetic acclimation may result from a relative decrease in the export of leaf sucrose and subsequent increase in cellular sucrose levels and sucrose cycling.