Effects of buyang huanwu decoction on peripheral nerve regeneration using silicone rubber chambers

This study investigated the effect of buyang huanwu decoction on the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Empty silicone rubber tubes with no further treatment were used as controls. Six weeks after implantation, 89% of the animals orally administered the buyang huanwu decoction exhibited regeneration across the nerve gaps, whereas only 70% had regenerated in the control group. Both qualitative and quantitative histology of the regenerated nerves revealed a more mature ultrastructural organization with significantly higher numbers of myelinated axons, larger endoneurial areas, higher axon densities and a larger percentage of axon area per total nerve area in the buyang huanwu group than in the controls. These results showed that the buyang huanwu decoction had a growth-promoting effect on the regenerated nerves.

Dose estimate of inhaled hafnium tritide using the ICRP 66 lung model

Metal tritide is widely used for research, purification, compression, and storage of tritium. The current understanding of metal tritide and its radiation dosimetry for internal exposure is limited, and ICRP publications do not provide the tritium dosimetry for hafnium tritide. The current radiation protection guidelines for metal tritide particles (including hafnium tritide) are based on the assumption that their biological behavior is similar to tritiated water, which is completely absorbed by the body. However, the solubility of metal tritide particles depends on the chemical form of the material. The biological half-live of hafnium tritide particles and the dosimetry of an inhalation exposure to those particles could be quite different from tritiated water. This paper describes experiments on the dissolution rate of hafnium tritide particles in a simulated lung fluid. The results showed that less than 1% of the tritium was dissolved in the simulated lung fluid for hafnium tritide particles after 215 d. The short-term and long-term dissolution half times were 46 and 4.28 x 10(5) d, respectively. This indicates that hafnium tritide is an extremely insoluble material. Self-absorption of beta rays in the hafnium tritide particles was estimated by a numerical method. The dose coefficients were calculated as a function of particle size using in vitro solubility data and a calculated self-absorption factor. The dose coefficient decreased with aerodynamic diameters in the range of 0.25 to 10 microm, mainly because the self-absorption factor decreased with increasing particle size. For a particle 1 microm in aerodynamic diameter, the dose coefficient of a hafnium tritide particle was about 10 times higher than that of tritiated water but was about 1.4 times lower than that calculated by ICRP Publication 71 for Type S tritiated particles. The ICRP estimate did not include a self-absorption factor and thus might have overestimated the dose. This finding has significant implications for current health protection guidelines.

Respiratory deposition patterns of salbutamol pMDI with CFC and HFA-134a formulations in a human airway replica

This paper describes a technique that uses a well-defined human airway replica and gamma counting as a standard method for evaluating and comparing the performance of medical inhalers and spacers. High-fidelity replicas reproduced as needed from master casts made from human cadavers include the oropharyngeal cavity, larynx, trachea, and five to nine generations of bronchi. Deposition in the small airways and alveoli region of the cast is simulated by material that passes through the upstream airways and is collected on foam filters. Deposition patterns in the respiratory tract replica were obtained by using radiolabel in the medical inhaler and by gamma scintigraphy. This technique was used to determine respiratory deposition patterns of salbutamol in a pressurized metered dose inhaler (pMDI) with chlorofluorocarbon (CFC, in-house formulation) and HFA-134 formulations (Proventil hydrofluoroalkane [HFA]). At an inspiration flow of 30 L/min, patterns in the salbutamol/CFC formula showed a high deposition in the oropharyngeal airway (78%) and a 16% deposition in the lung, similar to in vivo measurements reported in the literature. However, the salbutamol/HFA formula showed lower oral deposition (56%) but higher lung deposition (24%). The difference in the oral deposition patterns may be attributed to lower initial spray velocity, initial droplet evaporation rate, and possibly initial droplet sizes of Proventil HFA. The small orifice diameter (0.25 mm) of the Proventil HFA actuator produced a softer plume with a smaller impact force, resulting in lower oropharyngeal deposition. Cascade impactor measurements showed similar aerodynamic particle size distribution of the CFC and HFA formulations. We also showed that using spacers in the Proventil HFA resulted in a lower oropharyngeal deposition and higher lung deposition, indicating beneficial effects. Comparison of oropharyngeal deposition and those predicted by artificial throats used in the impactor measurements showed that, in general, the artificial throat predicted a lower deposition.

Characterization of nasal spray pumps and deposition pattern in a replica of the human nasal airway

Deposition patterns are described of a nasal spray formulation for a novel rhinovirus protease inhibitor. These patterns, which were generated from different nasal spray pumps, were characterized using a multisectional nasal airway model. A human nasal replica was made from an in vivo magnetic resonance imaging (MRI) scan of an adult male human. The nasal replica consisted of 77 acrylic plastic sections, 1.5-mm thick. Our data showed that the aerosols were deposited mainly in the anterior and turbinate regions with little passing beyond the nasopharyngeal region. Detailed deposition information from the turbinate region indicated that deposition was high toward the anterior portion where most deposition was concentrated on the inferior meatus. Spray droplets were also deposited in spots of the middle and posterior portions of the turbinate region, and this nonuniform deposition pattern may be correlated with the flow pattern. The spray angle and droplet size of the nasal spray were found to be important in influencing the deposition pattern in the nasal airway. The droplet size was determined by a laser-diffraction technique and the spray angle by high-speed photography. Larger droplets and a wider spray angle increased deposition in the anterior region of the nasal airway, which prevented more material from depositing in the turbinate region.

Automated construction of high-density comparative maps between rat, human, and mouse

Animal models have been used primarily as surrogates for humans, having similar disease-based phenotypes. Genomic organization also tends to be conserved between species, leading to the generation of comparative genome maps. The emergence of radiation hybrid (RH) maps, coupled with the large numbers of available Expressed Sequence Tags (ESTs), has revolutionized the way comparative maps can be built. We used publicly available rat, mouse, and human data to identify genes and ESTs with interspecies sequence identity (homology), identified their UniGene relationships, and incorporated their RH map positions to build integrated comparative maps with >2100 homologous UniGenes mapped in more than one species (approximately 6% of all mammalian genes). The generation of these maps is iterative and labor intensive; therefore, we developed a series of computer tools (not described here) based on our algorithm that identifies anchors between species and produces printable and on-line clickable comparative maps that link to a wide variety of useful tools and databases. The maps were constructed using sequence-based comparisons, thus creating "hooks" for further sequence-based annotation of human, mouse, and rat sequences. Currently, this map enables investigators to link the physiology of the rat with the genetics of the mouse and the clinical significance of the human.

Projection-invariant pattern recognition with logarithmic harmonic function and wavelet transform

A logarithmic harmonic filter can detect objects at different projection angles. The Mexican-hat wavelet function can extract edges of equal width for objects, regardless of their sizes. Hence incorporating wavelet filtering in the logarithmic harmonic filter can improve its performance. The theory is presented together with computer simulation. Finally, an experiment using a joint transform correlator is presented to verify the capability of the proposed filter.

Early colonic carcinoma with extensive lymph node metastases: case report and review of literature

An 81-year-old woman had an early carcinoma invading focally into the upper submucosa of the middle-transverse colon, which was accompanied by extensive lymph node metastases and resulted in a poor prognosis. Although her tumor was small and flat, a rim of pale yellow-speckled mucosa adjacent to the tumor enabled its earlier detection. To further study the exceptional lymph node metastases we studied the expression of intestinal trefoil factor and sialyl Tn antigen immunohistochemically on the resected specimen. Their simultaneous expression in lymph node metastasis further supports the aggressive nature of this tumor.

Investigation of the extent of gastric metaplasia in the duodenal bulb by using methylene blue staining

BACKGROUND AND AIMS

The existence of gastric metaplasia (GM) of the duodenal mucosa has been considered to be highly related to the recurrence of duodenal ulcers (DU). The aims of this study are to evaluate the usefulness of methylene blue staining in the detection of GM, and to clarify the relationship between GM and the deformity of the duodenal bulb.

METHODS

Fifteen patients with healed DU and four patients with symptoms of dyspepsia without evidence of ulcers were enrolled into this endoscopic study. During each endoscopy, methylene blue was sprayed evenly on the duodenal bulb, and biopsies were taken from blue-stained and unstained areas. The existence and extent of GM were assessed histologically and grossly. The correlation between duodenal bulb deformity and the extent of GM was also studied.

RESULTS

The mean score of methylene blue non-staining (MBNS) was 0, 1.30 +/- 0.15, and 3.00 +/- 0.00 in group A (non-ulcer patients), group B (patients with healed DU and with normal-shaped bulb) and C (patients with healed DU and with deformed duodenal bulb), respectively; showing significant differences among the groups (P < 0.05 in each). Both the existence and the grading of GM were higher in unstained specimens than in blue-stained specimens (100 vs 16.6%, P < 0.0001 and 3.62 +/- 0.09 vs 0.19 +/- 0.06, P < 0.001, respectively).

CONCLUSIONS

Methylene blue non-staining can be applied to investigate the existence and extent of GM in the duodenal bulb accurately. The incidence of GM in the duodenal bulb was higher in patients with healed ulcers than in non-ulcer patients. Patients with deformed duodenal bulbs have a higher extent of GM than those without deformed duodenal bulbs.

Childhood oral pemphigoid: a case report and review of the literature

Oral pemphigoid, defined as cicatricial pemphigoid limited to the oral cavity, is a clinical subset of cicatricial pemphigoid. Like cicatricial pemphigoid, it occurs mostly in middle-aged women and it is uncommon in children under 20 years of age. There are 11 cases of childhood cicatricial pemphigoid published previously in the English language literature, and four of them are oral pemphigoid patients. We present a case of the youngest oral pemphigoid patient reported yet. Because of the rareness of cicatricial pemphigoid in children, delayed diagnosis and treatment have been shown in many cases reported earlier. Clinical awareness and early recognition are, therefore, emphasized.

Genetic parameters of reproductive traits in Brown Tsaiya ducks artificially inseminated with semen from Muscovy drakes

A selection experiment on maximum duration of fertility of Brown Tsaiya ducks after artificial insemination (AI) with pooled Muscovy semen has been conducted since 1992. The Brown Tsaiya ducks were divided into two lines: a control line (T) with no selection and a selected line (S). The traits measured were the number of eggs set that were laid from Days 2 to 15 after one AI (NES), the number of fertile eggs at candling (NEF), the total number of dead embryos (NED), the maximum duration of fertility (MD), and the number of hatched mule ducklings (NEH). The selected trait was NEF. Six generations with a total of 2,127 females were measured. The variance components were estimated for each line in a multiple-trait animal model, using the restricted maximum likelihood (REML) methodology, which yields estimates free of bias caused by selection and inbreeding. Estimates of the heritability and genetic correlation from the two lines were very similar. Heritabilities in the S and T lines, respectively, were 0.14 and 0.10 for NES, 0.30 and 0.26 for NEF, 0.06 and 0.09 for NED, 0.28 and 0.21 for MD, and 0.18 and 0.19 for NEH. High and favorable genetic correlations existed between NEF and MD (0.96 and 0.92), between NEF and NEH (0.86 and 0.91), and between MD and NEH (0.90 and 0.82). The results suggested that selection for NEF could improve the maximum duration of fertility, but it could be useful to check the estimates of genetic parameters in a meat-type female duck.

Adjuvant sclerotherapy after ligation for the treatment of esophageal varices: a prospective, randomized long-term study

BACKGROUND

To assess the efficacy of adjuvant sclerotherapy after banding for the treatment of esophageal varices, a randomized trial was carried out of endoscopic variceal ligation (EVL) alone with sequential sclerotherapy versus sequential ligation-sclerotherapy (SLS) after banding with respect to variceal eradication, associated complications, and recurrence of varices.

METHODS

One hundred patients qualified for this study. Fourteen patients were not included for the following reasons: 6 chose not to participate, 4 had fundal varices, and 4 had some form of cancer. Of the remaining 86 patients in the study, 42 underwent EVL alone and the other 44 SLS. Variceal ligation was begun in the region of the gastroesophageal junction, with subsequent ligatures applied cephalad 3 to 5 cm; ligation was repeated every 2 weeks until variceal obliteration. For SLS, ligation was also begun in the region of the gastroesophageal junction and repeated until varices were reduced to F1 size. Subsequently, these patients underwent sclerotherapy with between 6 and 8 mL of sodium tetradecyl sulfate (free hand technique).

RESULTS

No significant differences were found between EVL alone and SLS with regard to variceal eradication, development of associated complications, and recurrent bleeding during a follow-up of 2 years. The probability of variceal recurrence requiring further treatment after 1 year was 14% for the SLS group and 26% for EVL group patients. Another year later, the probability of variceal recurrence was 24% and 45%, respectively, for the SLS and EVL groups.

CONCLUSIONS

Because a significantly lower rate of variceal recurrence was found for SLS patients, sequential sclerotherapy followed by ligation to eradicate those varices too small to easily band may be a better procedure.

Relationship of duodenal ulcer recurrence to gastric metaplasia of the duodenal mucosa and duodenal bulb deformity

BACKGROUND AND PURPOSE

This study investigated changes in the severity of gastric metaplasia (GM) of the duodenal mucosa before and after ulcer healing and Helicobacter pylori eradication. It also investigated whether deformity of the duodenal bulb affects the severity of GM and the likelihood of ulcer recurrence.

METHODS

Eleven patients were consecutively enrolled in this study. They all had duodenal ulcer(s) and H. pylori infection, for which they had received anti-H. pylori triple therapy during the active ulcer stage, and had all undergone serial endoscopic examinations during both the active ulcer and scarring ulcer stages, and at 1 year after ulcer healing. Duodenal biopsies were obtained at each endoscopy to identify the severity of GM. Duodenal ulcers were divided into three types by bulbar shape and GM was classified into four grades of severity.

RESULTS

All 11 patients had increased GM severity just after ulcer healing. The 1-year follow-up study revealed that the GM was unchanged in six of eight patients with grade 3 GM severity at the scarring stage, while in the other two it regressed to grade 1 or 2; these two patients suffered ulcer recurrence. A markedly deformed bulb (type III) was found in three patients, of whom two had ulcer recurrence.

CONCLUSION

Two characteristic conditions were found in patients with duodenal ulcer recurrence after H. pylori eradication: a markedly deformed bulb with grade 3 GM at the scarring stage, and a change in GM from high to low grade at or around the previous ulcer site after ulcer healing.

Diterpenoids from the leaves of Juniperus chinensis var. kaizuka

Two diterpenoids based on novel carbon skeletons, namely, 8,19-dioxo-8,14-seco-chinan-14,11-olide (1) and 8-oxo-8,14-seco-abiet-12-en-14,19-dial (2), have been isolated, together with two new abietane diterpenoids, 13 beta,14 beta-epoxyabiet-7-en-19,6 beta-olide (3) and 7 beta-hydroxyabieta-8,11,13-trien-19-al (4), from the leaves of Juniperus chinensis. Their structures were determined by spectroscopic methods, including 2D NMR, and, in the case of 1, X-ray crystallographic analysis.

Separation of pure and immunoreactive virus-like particles using gel filtration chromatography following immobilized metal ion affinity chromatography

A purification process was developed to obtain highly pure rVP2H particles, formed by a structural protein (VP2) of the infectious bursal disease virus (IBDV) with six additional histidine residues at its C-terminus. The ultimate goal was the development of an efficient subunit vaccine against IBDV infection. The particles within the infected High-Five (Hi-5) cell lysates were partially purified by employing immobilized metal ion (Ni(2+)) affinity chromatography (IMAC). The initial step could recover approximately 85% of immunoreactive rVP2H proteins but failed to separate the rVP2H particles from the free rVP2H proteins or its degraded products. To separate the particulate form from the free form of rVP2H, an additional step was added, which used either gel filtration chromatography or CsCl density gradient ultracentrifugation. Both were able to produce extremely pure rVP2H particles with a buoyant density close to 1.27 g/cm(3). However, the former method can process a larger sample volume than does the latter. By integrating IMAC and gel filtration chromatography, 1 mg of extremely pure rVP2H particles was routinely obtained from a 500 mL Hi-5 cell culture broth. The separation of the particulate form from the free form of rVP2H proteins exposes their respective immunogenicity to induce the virus-neutralizing antibodies and the ability to protect chickens from IBDV infection. Additionally, the abundant quantities of pure rVP2H particles coupled with their uniform dimensions facilitates an understanding of higher order structure of the immunogenic particles and can therefore result in improved vaccines against the virus.

Internal dosimetry for inhalation of hafnium tritide aerosols

Metal tritides with low dissolution rates may have residence times in the lungs which are considerably longer than the biological half-time normally associated with tritium in body water, resulting in long-term irradiation of the lungs by low energy beta particles and bremsstrahlung X rays. Samples of hafnium tritide were placed in a lung simulant fluid to determine approximate lung dissolution rates. Hafnium hydride samples were analysed for particle size distribution with a scanning electron microscope. Lung simulant data indicated a biological dissolution half-time for hafnium tritide on the order of 10(5) d. Hafnium hydride particle sizes ranged between 2 and 10 microns, corresponding to activity median aerodynamic diameters of 5 to 25 microns. Review of in vitro dissolution data, development of a biokinetic model, and determination of secondary limits for 1 micron AMAD particles are presented and discussed.

Acrokeratosis paraneoplastica (Bazex syndrome) with adenocarcinoma of the colon: report of a case and review of the literature

Acrokeratosis paraneoplastica is a rare disease and is uncommon even in patients with upper aerodigestive tract cancer. We report a 63-year-old man with a 1-month history of numerous pruritic lesions and vesicles on both feet. Although he had received local therapy, progressive dense scale formation involving both palms and both soles was found. Colonoscopy was performed because of hematochezia, and it revealed an early colon cancer. After the resection of the cancer, the skin lesions began to fall off dramatically. To the best of our knowledge, there is no report of acrokeratosis paraneoplastica associated with colon cancer in the literature. This is the first case report of acrokeratosis paraneoplastica associated with early colon cancer.

Structural analysis of the transcriptional activation region on Fis: crystal structures of six Fis mutants with different activation properties

The Fis protein regulates gene expression in Escherichia coli by activating or repressing transcription of a variety of genes. Fis can activate transcription when bound to DNA upstream of the RNA-polymerase-binding site, such as in the rrnB P1 promoter, or when bound to a site overlapping the -35 RNA polymerase binding site, such as in the proP P2 promoter. It has been suggested that transcriptional activation in both promoters results from interactions between specific amino acids within a turn connecting the B and C helices (the BC turn) in Fis and the C-terminal domain of the alpha-subunit of RNA polymerase (alphaCTD of RNAP). Here, crystal structures of six Fis BC turn mutants with different transcriptional activation properties, Q68A, R71Y, R71L, G72A, G72D and Q74A, were determined at 1.9 to 2.8 A resolution. Two of these mutants, R71Y and R71L, crystallized in unit cells which are different from that of wild-type Fis, and the structure of R71L offers the most complete Fis model to date in that the extended structure of the N-terminal region is revealed. The BC turn in all of these mutant structures remains in a nearly identical gamma gamma beta-turn conformation as present in wild-type Fis. Analyses of the molecular surfaces of the transactivation region of the mutants suggest that several residues in or near the BC turn, including Gln68, Arg71, Gly72 and Gln74, form a ridge that could contact the alphaCTD of RNAP on one side. The structures and biochemical properties of the mutants suggest that Arg71 is the most critical residue for contacting RNAP within this ridge and that the glycine at position 72 helps to stabilize the structure.

Image-plane cylindrical holographic stereogram

A two-step holographic process is introduced to fabricate a cylindrical multiplex hologram as an image-plane hologram. By adoption of the achromatic angle in the process the hologram is capable of generating an achromatic image. The most important factors, the location as well as the width of the viewing slits, that affect the quality of the observed image are analyzed and discussed. The change of aspect ratio for the observed image as a function of the viewing distance is theoretically and numerically analyzed. This method can not only eliminate the annoying picket-fence effect but can also increase the vertical viewing range for the observer. Computer simulations as well as experimental results are provided.

Ticlopidine-induced severe cholestatic hepatitis

We report a case study of an 86-year-old female patient with severe cholestatic hepatitis who was undergoing treatment with oral ticlopidine 250 mg daily for coronary artery disease. The patient had nausea and vomiting and was jaundiced after taking ticlopidine for 6 weeks. She was admitted to the hospital for further evaluation. Ultrasound and endoscopic retrograde cholangiopancreatography eliminated the presence of biliary obstruction. Results from a liver biopsy showed a histopathologic picture consistent with cholestatic hepatitis. Ticlopidine-induced cholestatic hepatitis has been reported 32 times in the foreign literature. This is the first reported severe cholestatic hepatitis (total bilirubin up to 43 mg/dl) case in Taiwan. Ticlopidine-related blood dyscrasia is a renowned adverse drug effect; liver function should be monitored in patients receiving ticlopidine therapy.

Correlation of bFGF, FGFR-1 and VEGF expression with vascularity and malignancy of human astrocytomas

OBJECTIVE

To investigate the correlation of angiogenic factor expression levels with the degrees of malignancy and vascularity and their clinicopathologic significance in astrocytomas.

STUDY DESIGN

Factor VIII-related antigen (FVIII-RAg) was used as the marker of endothelia and basic fibroblast growth factor (bFGF); FGF receptor (FGFR)-1 and vascular endothelial growth factor (VEGF) were qualitatively and quantitatively detected with immunohistochemistry and image analysis in 61 brain astrocytomas. The correlation with tumor grades, angiogenesis and prognosis was studied.

RESULTS

Measurement of FVIIIRAg expression could describe endothelial proliferation and vascularity, which were related to grade of tumor and prognosis. bFGF and VEGF expression levels in neoplastic astrocytes and endothelia were significantly different in various grades of astrocytoma. These angiogenic factors affected the positive reaction areas and integral optical densities of FVIII-RAg as well as survival time. In contrast, the expression of FGFR-1 was related to neither bFGF nor FVIIIRAg and had no significant effect on tumor malignancy.

CONCLUSION

Positive regulation by bFGF and autocrine/paracrine VEGF contributes to the growth and angiogenesis of astrocytomas. Measurement of endothelial cell proliferation with FVIIIRAg in tumor stroma and quantitative detection of angiogenic factor levels in neoplastic cells had prognostic value in brain astrocytomas. The results also indicate that inhibiting bFGF and VEGF expression and/or blocking their effects could be a very useful therapeutic strategy for malignant gliomas.

Role of the H protein in assembly of the photochemical reaction center and intracytoplasmic membrane in Rhodospirillum rubrum

Rhodospirillum rubrum is a model for the study of membrane formation. Under conditions of oxygen limitation, this facultatively phototrophic bacterium forms an intracytoplasmic membrane that houses the photochemical apparatus. This apparatus consists of two pigment-protein complexes, the light-harvesting antenna (LH) and photochemical reaction center (RC). The proteins of the photochemical components are encoded by the puf operon (LHalpha, LHbeta, RC-L, and RC-M) and by puhA (RC-H). R. rubrum puf interposon mutants do not form intracytoplasmic membranes and are phototrophically incompetent. The puh region was cloned, and DNA sequence determination identified open reading frames bchL and bchM and part of bchH; bchHLM encode enzymes of bacteriochlorophyll biosynthesis. A puhA/G115 interposon mutant was constructed and found to be incapable of phototrophic growth and impaired in intracytoplasmic membrane formation. Comparison of properties of the wild-type and the mutated and complemented strains suggests a model for membrane protein assembly. This model proposes that RC-H is required as a foundation protein for assembly of the RC and highly developed intracytoplasmic membrane. In complemented strains, expression of puh occurred under semiaerobic conditions, thus providing the basis for the development of an expression vector. The puhA gene alone was sufficient to restore phototrophic growth provided that recombination occurred.

Nominal shear or fracture mechanics in the assessment of composite-dentin adhesion?

This study addresses the anticipated problem of discriminating among high-performing dentin adhesives. The simplicity of the nominal shear bond test, despite being heavily criticized, has made it a routine procedure for the determination of bonding efficacy. A fracture mechanics approach has been suggested as a better assessment of bonding efficacy (Versluis et al., 1997). However, experimental complexity is a major limitation. It is hypothesized that a new, simplified interfacial fracture toughness test (Lin, 1994) will evaluate bonding agents differently if compared with the traditional shear bond test. Therefore, the objective of this study was to compare the performances of six dentin bonding agents subjected to the interfacial fracture toughness test (critical plane strain energy release rate) or to the nominal shear bond test (shear bond strength). Their performances were also characterized by scanning electron micrography of the fracture surfaces for evidence of dentin cohesive failure. Statistical analyses showed only marginal differences between these determinants of the two tests. However, when the analysis was applied only to the materials that had 100% frequency of dentin cohesive failure in shear testing, which also had high bonding efficacy, the difference in adhesive strengths between the two tests became significant. The reliability of the nominal shear test is questioned when dentin cohesive failure occurs, which usually is associated with high bonding efficacy. Since it is expected that bonding efficacy will increase further, the interfacial fracture toughness test is the preferred methodology to distinguish among high-performing dentin adhesives.

Disk-type multiplex holography

A theory for making a disk-type multiplex hologram is derived. This theory relates the final image point, as seen by the observer, to a point on the original three-dimensional object through a set of equations. From these equations the distortion of the image and the wavelength as seen by each individual eye can be evaluated. Computer simulation shows the characteristics of this hologram. Some experimental results also confirm these characteristics. By reversing the process and specifying a desired image, we generated a set of distorted two-dimensional originals. The hologram fabricated with these distorted images can generate nearly distortion-free images.

Amino acid conservation and clinical severity of human glucose-6-phosphate dehydrogenase mutations

More than a hundred naturally occurring mutations of human glucose-6-phosphate dehydrogenase (G6PD) have been identified at the amino acid level. The abundance of distinct mutation sites and their clinical manifestations make this enzyme ideal for structure-function analysis studies. We present here a sequence and structure combined analysis by which the severity of clinical symptoms resulting from point mutations of this enzyme is correlated with quantified degrees of amino acid conservation within 23 G6PD sequences from different organisms. Our analysis verifies, on a quantitative basis, a widely held notion that clinically severer mutations of G6PD usually occur at conserved amino acids. However, marked exceptions to this general trend exist which are most notably revealed by a number of mutations associated with chronic nonspherocytic hemolytic anemia (class I variants). When mapped onto a homology-derived structural model of human G6PD, these class I mutational sites of low amino acid conservation appear to localize in two spatially distinct clusters, both of which are populated with mutations consisting mainly of clinically severer variants (i.e. class I and class II). These results of computer-assisted analyses contribute to a further understanding of the structure-function relationships of human G6PD deficiency.