A pilot study on the effect of formulation and individual muscle mass on vitamin C absorption in randomized clinical study

The current study investigated that the vitamin C absorption in plasma depends on the individual muscle mass and the formulation including drinks (Vita 500), capsules, and tablets by using a randomized and double-blind clinical study. The volunteers were divided into two groups that depended on their muscle mass, including those whose muscle mass was greater than 40% ( ≥ $ \ge $ 40%) and less than 40% muscle mass (<40%). Levels of vitamin C in blood plasma was analyzed by high-performance liquid chromatography by ultraviolet detection (HPLC-UV). The existing HPLC method was modified according to lab conditions but maintained a constantly low pH sample reduction procedure. The analytical method validated stability, linearity, recovery, reliability, and accuracy. The vitamin C absorption was the highest at 120 min after ingesting Vita 500 (21.47 ± 15.99 µmol/L). It was higher in the group that has more than 40% muscle mass compared to other formulations, such as tablets and capsules. The results from the current study indicate that vitamin C formulations differently affect the vitamin C absorption, and its effect depends on the muscle mass. As the results, liquid type vitamin C formulations could enhance vitamin C absorption, which resulted in an improvement of vitamin C absorption according to muscle mass. PRACTICAL APPLICATION: The results of this study may recommend using vitamin C supplementation as liquid type. It may also provide evidence that people with higher muscle mass can absorb vitamin C more efficiently.

Facile synthesis of NF/ZnOx and NF/CoOx nanostructures for high performance supercapacitor electrode materials

NF/ZnOx nanocone and NF/CoOx nanoparticle electrode materials were fabricated on a nickel foam surface using a simple chemical bath deposition approach and assessed as an electrode material for high-performance supercapacitors.

Hepatoprotective and anti-obesity effects of Korean blue honeysuckle extracts in high fat diet-fed mice

[Purpose]

This study aimed to study the protective effects and mechanism of Blue Honeysuckle (BH) extracts (Berries of Lonicera caerulea L.) on non-alcoholic fatty liver disease (NAFLD) and obesity risk factors in a high fat-diet (HFD) model.

[Methods]

Animals adapted to HFD were selected after 1 week of adaption period and divided into 6 groups (8 mice in each group; 40 HFD-fed mice and 8 normal fat pellet diet (NFD)-fed mice). After the end of 12 weeks of continuous oral administrations of 3 different dosages of BH extract, 400, 200 and 100 mg/kg, or metformin 250 mg/kg, dissolved in a volume of 10 mL/kg distilled water, the hepatoprotective, hypolipidemic, hypoglycemic, nephroprotective, and anti-obesity effects were analyzed.

[Results]

The BH extract improved fat density and mass, adipocyte histopathology, hepatocyte hypertrophy, hepatic enzyme activity, lipid metabolism, and related gene expression including ACC1, AMPK α1 and AMPK α2 in hepatic tissue, leptin, UCP2, adiponectin, C/EBP α, C/EBPβ and SREBP1c in adipose tissue. Especially, 200 mg/kg of BH extract constantly improved NAFLD and obesity risk factors through AMPK upregulation-mediated hepatic glucose enzyme activity, lipid metabolism-related gene expression, and activation of the antioxidant defense system, to a level comparable to that of metformin 250 mg/kg in HFD-fed mice.

[Conclusion]

BH extract has the potential to reduce the risk factors associated with obesity, in addition to the remarkable effect of preventing NAFLD. Future research will need to be done to determine whether these results are consistent in human studies.

V2O5 nanorod electrode material for enhanced electrochemical properties by a facile hydrothermal method for supercapacitor applications

Metal oxides have attracted considerable interest due to their distinguished electrochemical properties and applications in multiple fields such as supercapacitors and solar cells.

A study on the changes in attractive force of magnetic attachments for overdenture

PURPOSE

Although magnetic attachment is used frequently for overdenture, it is reported that attractive force can be decreased by abrasion and corrosion. The purpose of this study was to establish the clinical basis about considerations and long term prognosis of overdenture using magnetic attachments by investigating the change in attractive force of magnetic attachment applied to the patients.

MATERIALS AND METHODS

Among the patients treated with overdenture using magnetic attachments in Dankook University Dental Hospital, attractive force records of 61 magnetic attachments of 20 subjects who re-visited from July 2013 to June 2014 were analyzed. Dental magnet tester (Aichi Micro Intelligent Co., Aichi, Japan) was used for measurement. The magnetic attachments used in this study were Magfit IP-B Flat, Magfit DX400, Magfit DX600 and Magfit DX800 (Aichi Steel Co., Aichi, Japan) filled with Neodymium (NdFeB), a rare-earth magnet.

RESULTS

Reduction ratio of attractive force had no significant correlation with conditional variables to which attachments were applied, and was higher when the maintenance period was longer (P<.05, r=.361). Reduction ratio of attractive force was significantly higher in the subject group in which attachments were used over 9 years than within 9 years (P<.05). Furthermore, 16.39% of total magnetic attachments showed detachment of keeper or assembly.

CONCLUSION

Attractive force of magnetic attachment is maintained regardless of conditional variables and reduction ratio increased as the maintenance period became longer. Further study on adhesive material, attachment method and design improvement to prevent detachment of magnetic attachment is needed.

Characteristics and osteogenic effect of zirconia porous scaffold coated with β-TCP/HA

PURPOSE

The purpose of this study was to evaluate the properties of a porous zirconia scaffold coated with bioactive materials and compare the in vitro cellular behavior of MC3T3-E1 preosteoblastic cells to titanium and zirconia disks and porous zirconia scaffolds.

MATERIALS AND METHODS

Titanium and zirconia disks were prepared. A porous zirconia scaffold was fabricated with an open cell polyurethane disk foam template. The porous zirconia scaffolds were coated with β-TCP, HA and a compound of β-TCP and HA (BCP). The characteristics of the specimens were evaluated using scanning electron microscopy (SEM), energy dispersive x-ray spectrometer (EDX), and x-ray diffractometry (XRD). The dissolution tests were analyzed by an inductively coupled plasma spectrometer (ICP). The osteogenic effect of MC3T3-E1 cells was assessed via cell counting and reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

The EDX profiles showed the substrate of zirconia, which was surrounded by the Ca-P layer. In the dissolution test, dissolved Ca(2+) ions were observed in the following decreasing order; β-TCP > BCP > HA (P<.05). In the cellular experiments, the cell proliferation on titanium disks appeared significantly lower in comparison to the other groups after 5 days (P<.05). The zirconia scaffolds had greater values than the zirconia disks (P<.05). The mRNA level of osteocalcin was highest on the non-coated zirconia scaffolds after 7 days.

CONCLUSION

Zirconia had greater osteoblast cell activity than titanium. The interconnecting pores of the zirconia scaffolds showed enhanced proliferation and cell differentiation. The activity of osteoblast was more affected by microstructure than by coating materials.

Extraktionen von Ginsenosiden aus Ginseng-Wurzeln mit flüssigem Ammoniak, Methanol-Wasser oder Wasser/ Extractions of Ginsenosidesj from Ginseng Roots with Liquid Ammonia, Methanol-Water or Water

Extractions of ginsenosides from ginseng roots with liquid ammonia, methanol/water (60:40; v/v) or water were carried out. The extracts have been analyzed qualitatively and quantitatively to valuate yield and selectivity of extractions of ginsenosides. Water supplied the lowest yield. The yields of extracts with liquid ammonia were higher than those with m ethanol-water (60%). Yields of the ginsenosides Rb1, Rb2, Rc and Rd by extracting with liquid ammonia are about twice as much as those of the extraction with methanol-water (60%). It was proved by HPLC that malonyl-ginsenosides m -Rb1 m-Rb2, m-Rc and m-Rd were converted to the corresponding neutral ginsenosides by extraction with liquid ammonia. Because of high yields of extracts and simultaneous increase of the contents of Rb1, Rb2, Rc and Rd the extraction with liquid ammonia is obviously superior to the other extraction methods.

Furtherm ore, ginsenosides from ginseng roots were extracted by alkaline methanol-water (60%) solutions. Alternatively, the extracts of the methanol-water (60%) extraction were treated with sodium hydroxide solution. Both methods convert also the malonyl-ginsenosides to neutral ginsenosides

Residual bone height measured by panoramic radiography in older edentulous Korean patients

PURPOSE

The aim of this study was to obtain statistical data on the residual bone height at different natural tooth positions by panoramic radiography in edentulous Korean patients aged 60-90 years.

MATERIALS AND METHODS

The study included the diagnostic panoramic radiographs of 180 randomly selected edentulous patients without systemic diseases affecting bone. The radiographic selection criteria included absence of obvious facial asymmetry, clearly visible anatomic structures, and no surgical and fracture history. The panoramic radiographs of 79 patients met these criteria and were used in the analysis. The same researcher processed all the radiographs by using a standardized method. The height of the residual bone was measured at 18 predetermined sites (7 in the maxilla and 11 in the mandible) on digitized and printed radiographs by using a Digimatic caliper, triangle, and ruler. Gender- and age-related differences were statistically analyzed by using the t-test and rank-sum test (α=0.05).

RESULTS

The maxillary residual bone height did not show significant gender-related differences, but male patients had significantly higher residual bone in the mandible(P<.05). No significant height differences at the measured sites were noted among the 60s, 70s, and 80s age groups.

CONCLUSION

Dentists should pay greater attention to older female edentulous patients because they are more prone to rapid residual bone resorption. Residual bone resorption may not be affected by age.

Evaluation on the efficacy and safety of calcium metaphosphate coated fixture

PURPOSE

The purpose of this study was to assess the difference in efficacy between calcium metaphosphate (CMP)-coated implant fixtures and conventional resorbable blasted media (RBM) processed implant fixtures.

MATERIALS AND METHODS

This study targeted 50 implants from 44 patients who visited Dankook University Dental Hospital. Implantations were done separately for RBM treated and CMP-coated implants, although their design was the same. Calcium metaphosphate has a quicker biodegradation process through hydrolysis compared to other phosphate calcium groups. For the first year of the implantation, the resorption volume of marginal bone analyzed via radiography and perio-test value were measured, under the check plan. Their analyses were composed of a non-inferiority trials test. A 95% level of reliability was used.

RESULTS

In the comparative analysis of the resorption volume of marginal bone and the perio-test value, no statistically significant difference was found between the CMP-coated implants and RBM implants.

CONCLUSION

One year after the implant placement, CMP-coated implants were found not to be inferior to the conventional RBM implants.

Association between urine cotinine levels, continuous performance test variables, and attention deficit hyperactivity disorder and learning disability symptoms in school-aged children

BACKGROUND

We examined the cross-sectional relationship between environmental tobacco smoke exposure, continuous performance test (CPT) measures, and attention deficit hyperactivity disorder (ADHD) or learning disability symptoms in school-aged children.

METHOD

In total, 989 children (526 boys, mean age 9.1 ± 0.7 years), recruited from five South Korean cities participated in this study. We used urine cotinine as a biomarker for environmental tobacco smoke exposure, and obtained the children's scores on a CPT. Parents completed the Korean versions of the ADHD rating scale-IV (ADHD-RS) and learning disability evaluation scale (LDES). Using generalized linear mixed model (GLMM), we assessed the associations between urine cotinine concentrations, neuropsychological variables, and symptoms of ADHD and learning disabilities. Additionally, we conducted structural equation models to explore the effects' pathways.

RESULTS

After adjusting for a range of relevant covariates, GLMM showed urinary cotinine levels were significantly and positively associated with CPT scores on omission errors, commission errors, response time, and response time variability, and with parent- and teacher-rated ADHD-RS scores. In addition, urine cotinine levels were negatively associated with LDES scores on spelling and mathematical calculations. The structural equation model revealed that CPT variables mediated the association between urine cotinine levels and parental reports of symptoms of ADHD and learning disabilities.

CONCLUSIONS

Our data indicate that environmental exposure to tobacco smoke is associated with ADHD and learning disabilities in children, and that impairments in attention and inhibitory control probably mediate the effect.

Bone-implant interface with simulated insertion stress around an immediately loaded dental implant in the anterior maxilla: a three-dimensional finite element analysis

PURPOSE

The purpose of the present study was to investigate the stress distribution around the bone-implant interface and the effect of the length of an immediately loaded implant in the anterior maxilla using a finite element model with simulated loading stresses.

MATERIALS AND METHODS

Four-mm-diameter external-hex implants with different lengths (8.5, 10.0, 11.5, 13.0, and 15.0 mm) were used in this study. The anterior maxilla was assumed to be D3 bone quality. All of the material was assumed to be homogenous, isotropic, and linearly elastic. Average bone deformation during implant placement was calculated through the simulation process, and using this, insertion stress was created. The bone-implant interface was constructed using a contact element to simulate a nonosseointegrated condition. Then, 176 N of static force was applied at the middle of the palatoincisal line angle of the abutment at a 120-degree angle to the long axis of the abutment. The von Mises stresses were measured at intervals of 0.25 mm along the bone-implant interface.

RESULTS

Prior to loading, the stresses were evenly distributed around the implant and highly concentrated in the cortical area. When the load was applied, von Mises stresses were concentrated in the cortical bone of the implant neck area. More favorable stress distribution was seen with increasing implant length. However, when the implant length reached 15.0 mm, the stresses increased.

CONCLUSIONS

In the maxilla, when immediate loading is applied after implant placement, 11.5- and 13.0-mm-long single implants showed more favorable stress patterns than the others analyzed. If implants longer than 15.0 mm are used in immediate loading, sufficient bone volume in the recipient site should be considered an important factor.

Hard X-ray microbeam lithography using a Fresnel zone plate with a long focal length

Focused hard X-ray microbeams for use in X-ray nanolithography have been investigated. A 7.5 keV X-ray beam generated at an undulator was focused to about 3 µm using a Fresnel zone plate fabricated on silicon. The focused X-ray beam retains a high degree of collimation owing to the long focal length of the zone plate, which greatly facilitates hard X-ray nanoscale lithography. The focused X-ray microbeam was successfully utilized to fabricate patterns with features as small as 100 nm on a photoresist.

An effect of immediate dentin sealing on the shear bond strength of resin cement to porcelain restoration

PURPOSE

The aim of this study was to determine differences in shear bond strength to human dentin using immediate dentin sealing (IDS) technique compared to delayed dentin sealing (DDS).

MATERIALS AND METHODS

Forty extracted human molars were divided into 4 groups with 10 teeth each. The control group was light-cured after application of dentin bonding agent (Excite® DSC) and cemented with Variolink® II resin cement. IDS/SE (immediate dentin sealing, Clearfil™ SE Bond) and IDS/SB (immediate dentin sealing, AdapterTM Single Bond 2) were light-cured after application of dentin bonding agent (Clearfil™ SE Bond and Adapter™ Sing Bond 2, respectively), whereas DDS specimens were not treated with any dentin bonding agent. Specimens were cemented with Variolink® II resin cement. Dentin bonding agent (Excite® DSC) was left unpolymerized until the application of porcelain restoration. Shear strength was measured using a universal testing machine at a speed of 5 mm/min and evaluated of fracture using an optical microscope.

RESULTS

The mean shear bond strengths of control group and IDS/SE group were not statistically different from another at 14.86 and 11.18 MPa. Bond strength of IDS/SE group had a significantly higher mean than DDS group (3.14 MPa) (P < .05). There were no significance in the mean shear bond strength between IDS/SB (4.11 MPa) and DDS group. Evaluation of failure patterns indicates that most failures in the control group and IDS/SE groups were mixed, whereas failures in the DDS were interfacial.

CONCLUSION

When preparing teeth for indirect ceramic restoration, IDS with Clearfil™ SE Bond results in improved shear bond strength compared with DDS.

A comparative study on the accuracy of the devices for measuring the implant stability

STATEMENT OF PROBLEM

How the ISQ values measured by Osstell™ and Osstell™ Mentor are related, and whether the ISQ values acquired from the two machines changes in accordance with changes in implant stability are not yet fully understood.

PURPOSE

The aim of this study was to find out correlation between the ISQ values acquired from Osstell™ and Osstell™ Mentor, and to evaluate the clinical effectiveness and accuracy of two devices.

MATERIAL AND METHODS

Sixty two implants were inserted into 47 patients, and their ISQ values were measured using Osstell™ and Osstell™ Mentor. In the first stage surgery, the ISQ values of forty four implants inserted into thirty five patients were measured. In the second stage surgery, the values of fifty implants inserted into thirty seven patients were measured. The values were analyzed to determine the difference between the mean ISQ values of Osstell™ and Osstell™ Mentor. In addition, the correlation between implants used in the first and second stage of surgery with regard to their types and areas of insertion were analyzed. The difference between the ISQ values of 32 implants in each patient during the first and second stage was analyzed. The statistical assessment was carried out using SPSS V. 12.0 for Win. (SPSS Inc., Chicago, USA). The Pearson correlation coefficient was used to examine the correlation between Osstell™ and Osstell™ Mentor in the first and second stages of surgery, whereas the difference between their ISQ values was evaluated using a paired t-test.

RESULTS

In the first stage, the mean ISQ value for Osstell™ and Osstell™ Mentor was 70.84 and 75.09, respectively, showing a significant difference (P < .01). In the second stage, the mean ISQ value of Osstell™ and Osstell™ Mentor was 71.76 and 75.94, respectively, also showing a significant difference (P < .01). The difference between the ISQ values in patients in the first and the second stages was significant with both instruments.

CONCLUSION

The significant difference in the values obtained using the Osstell™ and Osstell™ Mentor between the first and second stages of implant surgery indicates that these values can be a convenient and precise way for evaluating the implant stability in clinical practice.

Treadmill exercise improves cognitive function and facilitates nerve growth factor signaling by activating mitogen-activated protein kinase/extracellular signal-regulated kinase1/2 in the streptozotocin-induced diabetic rat hippocampus

This study aimed to investigate the effects of regular treadmill exercise on nerve growth factor (NGF) expression, the improvement of cognitive function in the hippocampus of diabetic rats, and to understand the molecular mechanisms through which the relevant signaling factors act. We investigated the effects of regular treadmill exercise for 6 weeks on NGF, tyrosine kinase receptor A (TrkA), p75 receptor, phosphatidylinositol 3-kinase (PI3-K), mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase 1/2 (Erk1/2), cyclic AMP response element-binding protein (CREB), and caspase-3 protein levels; we also assessed cell survival and cognitive function. Forty male Sprague-Dawley rats were divided into four groups: (1) normal control group (NCG: n=10); (2) normal exercise group (NEG: n=10); (3) diabetes control group (DCG: n=10), and (4) diabetes exercise group (DEG: n=10). Diabetes was induced by injecting streptozotocin (STZ; 55 mg/kg dissolved in 0.05 M citrate buffer, pH 4.5, i.p.) into rats. Rats were subjected to treadmill exercise for 5 days a week over 6 weeks, and the speed of the treadmill was gradually increased. In a passive avoidance test, the retention latency in the DCG was significantly shorter than that in the DEG (P<0.05). Increased 5-bromo-2'-deoxyuridine-5'-mono-phosphate (BrdU)-labeled cells (P<0.001) and significant increases in NGF and TrkA protein levels were observed in the hippocampal dentate gyrus in the NEG and DEG (P<0.001 and P<0.01, respectively). The p75 receptor protein level significantly increased in the NEG but decreased in the DCG (P<0.001). The p-PI3-K and t-CREB protein levels significantly increased in the NEG (P<0.001 and P<0.05, respectively), whereas t-Erk1/2 significantly decreased in the DCG (P<0.01, P<0.01, respectively). p-Erk1/2 and p-CREB protein levels significantly increased in the NEG and DEG (P<0.001, P<0.001, and P<0.01, respectively). Caspase-3 protein levels significantly increased in the DCG (P<0.001). These results show that treadmill exercise improves cognitive function, increases the number of BrdU-labeled cells, and increases NGF levels, by the activation of the MAPK/Erk1/2 signaling pathway in the hippocampus of diabetic rats.

Comparative Study of Extraction Techniques with Ammonia or Methanol/Water for the Isolation of Ginsenosides Using HPLC/MS

Roots of ginseng plants have been extracted with liquid ammonia or methanol/water (60:40 v/v). The extracts were characterized by means of a gradient HPLC/MS method and the results were compared with each other. The ginsenosides Rb1, Rb2, Rc, Rd, Re, Rf, Rg1 and Ro including the malonyl ginsenosides m-Rb1, m-Rb2, m-Rc and m-Rd could be identified. Contrary to previous reports suggesting that during the extraction with liquid ammonia malonyl ginsenosides are totally converted to neutral ginsenosides, it could now be demonstrated by use of mass spectrometry that even after an extraction time of 4 h malonyl ginsenosides can be detected. However, the amount of malonyl ginsenosides was reduced by about one order of magnitude.

The neutral ginsenosides were not changed by liquid ammonia. The mass spectrometric detection has been performed by use of the quasi-molecule ion [M+Na]+ and some specific fragment ions.

Effects of stress on female rat sexual function

This study was undertaken to investigate whether prolonged stress interferes with sexual behavior and changes biochemical and physiologic mechanisms. Experiments were repeated three times with different rats in each period. In all, 63 female Sprague-Dawley rats were employed, with 21 rats in each period, and the control group was maintained at room temperature with free access to food and water. The stress group was maintained under a scheduled stress condition for 10 days, and seven rats from the group were randomly selected and exposed to the control environment for 10 days as the recovery group. Sexual behavior, hormonal values, and neuronal and endothelial nitric oxide synthase (nNOS and eNOS) expressions of vaginal tissue were analyzed and compared. Serum testosterone levels were significantly elevated in the stress and recovery groups (P<0.05). Female rats in the stress group showed reduced receptivity to their male mates (P<0.05). Western blot analysis demonstrated that nNOS and eNOS expressions were significantly lower in the stress group (P<0.05) than in the other groups. We conclude that chronic physical stress modifies the sexual behavior of female rats through a mechanism believed to involve complex changes in sex hormones, endocrine factors, and neurotransmitters.

Pirfenidone suppressed the development of glomerulosclerosis in the FGS/Kist mouse

Pirfenidone (PFD) is a newly developed anti-fibrotic agent. We evaluated the effect of PFD for the prevention of renal fibrosis using a spontaneous progressive glomerulosclerosis animal model, FGS/Kist mice. Male and female FGS/Kist mice were fed a diet containing 0.5% PFD or the same control diet (CD) without PFD, for 1, 2, or 3-month periods. Body weight was monitored for the general effect of PFD on the mice. Proteinuria and glomerular filtration rate (GFR) were evaluated for renal function. The sclerosis index was examined for the morphological changes. There were no significant changes in body weight between the PFD and control groups in both sexes. Proteinuria levels were low in all the PFD groups compared to the corresponding CD groups. The sclerosis scores were also reduced in both sexes of the 3-month PFD groups (p<0.05), and glomerular filtration rates were increased in both sexes of the 3-month PFD groups compared to the CD groups. The treatment of PFD for 1 or 2-month periods did not have statistic significances but the treatment for 3 months had statistic significances in sclerosis and GFR compared to CD groups. These results suggested that long-term administration of PFD suppressed the progression of glomerulosclerosis and improved renal function of the FGS/Kist mice.

Comparison of Tc-99m sestamibi and TI-201 uptake in multiple myeloma

The authors report abnormal Tc-99m sestamibi (MIBI) and TI-201 uptake in a 62-year-old patient with histologically and biochemically proved myeloma. TI-201 imaging was undertaken for tumor evaluation, and 3 days later a Tc-99m MIBI study showed diffuse and focal marrow uptake with focal skull lesions, whereas TI-201 did not show skull lesions. After treatment, follow-up Tc-99m MIBI whole-body imaging was performed and the marrow uptake was decreased.

The malonate decarboxylase operon of Acinetobacter calcoaceticus KCCM 40902 is regulated by malonate and the transcriptional repressor MdcY

A regulatory gene-like open reading frame oriented oppositely to mdcL, coined mdcY, was found upstream from the structural genes of the mdcLMACDEGBH operon in Acinetobacter calcoaceticus KCCM 40902. To elucidate the function of this gene, mdcY was expressed in Escherichia coli, and the MdcY protein was purified to homogeneity. Its DNA binding activity and binding site were examined by gel retardation and footprinting assays in vitro and by site-directed mutagenesis of the binding sites in vivo. The regulator bound target DNA regardless of the presence of malonate, and the binding site was found centered at -65 relative to the mdcL transcriptional start site and contains a 12-bp palindromic structure (5'-ATTGTA/TACAAT-3'). Using a promoter fusion to the reporter gene luc, we found that the promoter P(mdcY) is negatively regulated by MdcY independent of malonate. However, the promoter P(mdcL) recovered its activity in the presence of malonate. When mdcY was introduced into A. calcoaceticus KCCM 40902 in which the gene is inactivated by an IS3 family element, malonate decarboxylase was significantly repressed in cultures growing in acetate, succinate, or Luria-Bertani medium. However, in cells growing in malonate, malonate decarboxylase was induced, indicating that MdcY is a transcriptional repressor and that malonate or a product resulting from malonate metabolism should be the intracellular inducer of the mdc operon.

Radiation therapy for heterotopic ossification in a patient with traumatic brain injury

Radiation therapy has been known to have a prophylactic effect for heterotopic ossification (HO), but until now it has not been known to have a therapeutic effect for established HO. We report a case of established HO compounded with a sudden increase in activity, that was improved with radiation therapy. A patient with traumatic brain injury had HO in both hips and thighs two months after the initial trauma. The existing level of HO activity suddenly increased seven months after the initial trauma, and was accompanied by severe pain that was refractory to indomethacin. We assumed that the pain was caused by the increased activity of HO on the basis of clinical symptoms and laboratory results. Initially, the patient received radiation therapy to the left lower extremity, with a total dose of 20 Gy in ten fractions. Next, the patient received radiation therapy at the same dosage to the right lower extremity, after which the pain and level of serum alkaline phosphatase significantly decreased. The patient experienced a mild pancytopenia as a side effect of the radiation therapy, but it was not severe enough to stop the radiation therapy, given the patient's suffering from the increased HO activity.

Viable tissue in an area of severely reduced perfusion demonstrated with I-123 iomazenil brain SPECT imaging of benzodiazepine receptors

A 70-year-old woman who experienced transient left hemiparesis had 90% stenosis of the right internal carotid artery. CT revealed small low-density areas in the subcortical frontal area. Baseline cerebral blood flow was reduced, and vasoreactivity was poor in the right frontoparietal area according to I-123 IMP brain SPECT with acetazolamide. The distribution of I-123 iomazenil was normal on the delayed SPECT image but reduced in the early SPECT image, mimicking baseline cerebral blood flow. The distribution of I-123 iomazenil SPECT on the delayed image reflected the normal binding potential of the benzodiazepine receptor and thus identified viable tissue in an area of severely reduced perfusion. These findings were confirmed by positron emission tomography.

The influence of simultaneous versus delayed placement on the stability of titanium implants in onlay bone grafts. A histologic and biomechanic study in the rabbit

A rabbit model was used to study the healing and stability of titanium implants in free bone grafts, placed simultaneously or after 8 weeks of healing and followed for 24 weeks. The skull bone was used as donor site and the tibial metaphysis as recipient site. Stability measurements were performed by using resonance frequency analysis (RFA) at implant placement and after 4, 8, 16 and 24 weeks of healing. Statistically significant higher resonance frequencies were measured at all time points for the delayed approach implants. Removal torque tests after 24 weeks revealed no differences between the two procedures. Histologic ground sections were prepared on specimens taken after 8, 16 and 24 weeks of healing. More bone-implant contacts were observed in the bone graft for the implants inserted in a delayed fashion, while there was no statistically significant difference in the degree of total bone-implant contact between the two groups. It is concluded that delayed implant placement in autogenous onlay bone grafts results in a better integration and stability of the implants.

Visualization of pressure-dependent luxury perfusion in a patient with subacute cerebral infarction

Luxury perfusion characterized by depressed metabolism compared with CBF might be changed by decreasing cerebral perfusion pressure during the sitting position. A 77-yr-old man with subacute cerebral infarction was studied with brain X-ray computed tomography (CT), raise-up test with 99mTc-d,1-hexamethylpropyleneamine oxime (HMPAO) brain single photon emission tomography (SPECT) and positron emission tomography (PET). Brain X-ray CT revealed a low-density area in the left middle cerebral artery (MCA) anterior area. Raise-up 99mTc-HMPAO brain SPECT revealed decreased uptake in the left MCA anterior area in the sitting position and subsequent supine 99mTc-HMPAO brain SPECT revealed hot accumulation there. PET study in the supine position demonstrated some differences between CBF and the cerebral metabolic rate for oxygen in the left MCA anterior area, indicating luxury perfusion. CBF in the area of luxury perfusion might be decreased during the sitting or standing position and increased during the supine position by dysautoregulation of the cerebral vessels in the luxury perfusion during the subacute infarct.

Baumkuchen map analysis to detect postural cerebral hypoperfusion with upright 99Tcm-HMPAO brain SPET

We have evaluated a polar cortical flow Baumkuchen map (BK map), constructed from projection data by inwardly layering cortical flow stripes from the base to the apex, to detect postural cerebral hypoperfusion using 99Tcm-HMPAO brain SPET. A circular cortical perfusion outline was constructed from sinogram data at a 20% threshold; a ring was then formed by constructing an inner line with a radius equal to half that of the outer line. This ring on the transaxial image was superimposed onto the cortical image, then divided into 60 portions at 6 degrees intervals from the centre. The maximal number of counts per pixel within each sector was determined, translated into polar coordinate profiles and displayed as a polar map. We studied 11 patients with unilateral stenosis of the internal carotid artery or middle cerebral artery (MCA) and 7 patients without stenosis, using upright and supine (rest) 99Tcm-HMPAO brain SPET Cerebral perfusion was visibly altered on the BK maps of all 11 patients with arterial stenosis and on the transaxial images of 8 of them. A semi-quantitative analysis of the BK maps using a ratio of the counts in the regions of interest over the right and left MCA areas, showed that the mean of the ratios was significantly lower in the upright images than in the upright + rest and rest images (P = 0.0044 and 0.0033, respectively). Although the difference in the means of the ratios between the upright and upright + rest images was significant for both the BK map and transaxial image data (P = 0.0044 and 0.0051, respectively), the BK map was accurate in detecting changes in perfusion in the upright position. We conclude that BK map analysis is useful for detecting changes in patients examined using upright brain SPET.

Visualization of frontal postural hypoperfusion in patients with Takayasu arteritis with upright 99Tcm-HMPAO brain SPET

Takayasu arteritis is a chronic inflammatory angiopathy involving the cerebral arteries. We performed upright and supine 99Tcm-HMPAO brain single photon emission tomography (SPET) to investigate the cerebral perfusion pattern in eight patients with Takayasu arteritis, and we compared the results with those acquired using 123I-IMP and acetazolamide in six patients. SPET images were evaluated visually and semi-quantitatively. Hypoperfusion was visually detected in all eight patients during the provocative upright test with 99Tcm-HMPAO, and in three of six tested using acetazolamide and 123I-IMP. Semiquantitative analysis revealed that the mean cortical-to-cerebellar ratio in the upright position was significantly changed compared to that in the supine position in the right frontal area (from 0.86 +/- 0.07 to 0.91 +/- 0.09; P < 0.05). Change was also seen in the left frontal area (from 0.85 +/- 0.08 to 0.91 +/- 0.08; P < 0.05). No significant change was seen in other cortical areas with the upright test or in any areas with the acetazolamide test. We postulate that reduced arterial compliance may cause frontal postural hypoperfusion in patients with Takayasu arteritis due to poor functioning of autoregulation and arterial stenosis or occlusion. We conclude that the provocative upright test with 99Tcm-HMPAO brain SPET can detect abnormal patterns of cerebral perfusion in patients with Takayasu arteritis that might be missed by brain SPET using 123I-IMP and acetazolamide.

All 4 bases of both strands at -9 and -8 in T7 promoter are needed to be substituted by SP6-specific bases to switch promoter specificity

It has previously been shown that a substitution of two base pairs at -9 and -8 in T7 promoter by SP6 promoter-specific base pairs alone is sufficient to make the T7 variant become an SP6 promoter, abolishing T7 promoter activity [Lee, S. S., and Kang, C. (1992) Biochem. Int. 26, 1-5]. In order to determine which of the 4 bases on both strands at the two positions is involved in the discriminative specificity, each base or each pair of bases was substituted by SP6-specific base(s), allowing one or two mismatches. The results show that all-four-base substitution only is capable of switching promoter specificity, and that all the four bases are substantially involved in T7 promoter activity.