SATB2-associated syndrome presenting with Rett-like phenotypes

The SATB2-associated syndrome (SAS) was proposed recently, after the SATB2 gene was initially discovered to be associated with isolated cleft palate. This syndrome is characterized by intellectual disability with delayed speech development, facial dysmorphism, cleft or high-arched palate, and dentition problems. Here, we describe two novel SATB2 sequence variants in two unrelated patients presenting with Rett-like phenotypes. We performed trio-based whole-exome sequencing in a 17-month-old girl presenting with severe retardation and Rett-like phenotypes, which revealed a de novo missense variant in SATB2 (p.Glu396Gln). Moreover, targeted sequencing of the SATB2 gene was performed in a 2-year-old girl with severe psychomotor retardation, facial hypotonia, and cleft palate who also exhibited some features of Rett syndrome. A nonsense variant in SATB2 was identified in this patient (p.Arg459*). This study expanded the clinical and genetic spectrum of SAS. SATB2 variants should be considered in cases with psychomotor retardation alone or in any cases with Rett-like phenotypes, regardless of the typical features of SAS such as cleft palate.

Phase Transformation Behavior at Low Temperature in Hydrothermal Treatment of Stable and Unstable Titania Sol

Nanosize titania sol was prepared from titanium tetraisopropoxide (TTIP) and conditions for the formation of stable sol were identified. As the H+/TTIP mole ratio decreased and H2O/TTIP mole ratio increased, stable sol was likely to be formed. The size and crystallinity remained unchanged after hydrothermal treatment of the stable sol at between 160 and 240°C. However, hydrothermal treatment of unstable sol produced rod-like particles and crystallinity of particles was changed from anatase to rutile. This difference in phase transformation at low hydrothermal treatment temperature was likely to be caused by the fact that stable sol remained to be stable even after hydrothermal treatment, while unstable sol had a tendency to be aggregated.

Horseradish peroxidase transport across rat alveolar epithelial cell monolayers

PURPOSE

To evaluate the transport characteristics of horseradish peroxidase (HRP, a nonspecific fluid-phase endocytosis marker) across an in vitro model of tight (> 2,000 ohm-cm2) rat alveolar epithelial cell monolayers grown on tissue culture-treated polycarbonate filters.

METHODS

Unidirectional HRP fluxes were estimated from the appearance rate of HRP in the receiver fluid following instillation in the donor fluid as a function of donor [HRP] and temperature. Molecular species present in either bathing fluid were determined at the end of flux experiments using fluorescein isothiocyanate (FITC)-labeled HRP by gel permeation chromatography. Cell-associated HRP activity at the end of the transport experiment was determined, as were the rates of recycling and transcellular movement of HRP. An enzymatic assay was uses to quantify HRP activity in the bathing fluid and cells.

RESULTS

Unidirectional HRP fluxes were symmetric and increased linearly with up to 50 microM donor [HRP]. The apparent permeability coefficient of HRP was reduced by 3.5 times upon lowering the temperature from 37 to 4 degrees C. About 50% of the FITC-labeled species present in either receiver fluid was intact HRP. Cell-associated HRP estimated from apical HRP incubation was about 4 times greater than that from basolateral incubation. Recycling into apical fluid of cell-associated HRP following apical incubation occurred rapidly with a half-time (T1/2) of approximately 5 min, reaching a plateau at approximately 67% of the initial cell-associated HRP, while transcellular movement of HRP (into basolateral fluid) took place with a T1/2 of approximately 20 min, attaining a steady-state at approximately 13% of the initial cell-associated HRP. Basolateral recycling of HRP was also rapid (T1/2 = approximately 5 min) reaching a steady-state at approximately 35% of the initial basolaterally-bound HRP. Transcellular movement of HRP following basolateral incubation was slower (T1/2 = approximately 70 min), leveling off at 50% of the initial cell-associated HRP.

CONCLUSIONS

HRP appears to be transported relatively intact (approximately 50%) across rat alveolar epithelial barrier via nonspecific fluid-phase endocytosis. The transepithelial pinocytotic rate of alveolar epithelial cells is estimated to be about 25 nL/cm2/h.

Stromal cell activity in bone marrow from the tibia and iliac crest of patients with rheumatoid arthritis

Bone marrow aspirates were obtained from the iliac crest and tibial epiphysis in 23 patients with rheumatoid arthritis (RA) who were undergoing total knee arthroplasty. The number of fibroblast colony-forming units (CFU-F), which contain osteogenic precursor cells, and alkaline phosphatase (ALP) activity, as a marker of the osteoblastic phenotype. were compared between the iliac and tibial marrow for each patient. The prevalence of CFU-F in tibial marrow was similar to that in iliac marrow (96% vs 100%, respectively). However, the average number of CFU-F per 4 x 10(5) bone marrow mononuclear cells was significantly lower in tibial marrow than in iliac marrow (8.2 vs 28.1, respectively; P < 0.01). Although ALP activity was detected in all iliac and tibial marrow specimens, it was significantly lower in tibial marrow compared with iliac marrow (3.7 vs 11.9 nmol/min/mg protein, respectively; P < 0.01). In addition, there was a significant correlation between the patient's age and the number of CFU-F in iliac marrow (r = -0.547; P < 0.01), although there was no correlation in tibial marrow. These results demonstrate that the osteogenic activity of bone marrow varies at different sites in patients with RA. The data may also contribute to further investigation into the differential effects of various disease processes on systemic as well as local stromal cell activity in bone marrow.

The gene fimU affects expression of Salmonella typhimurium type 1 fimbriae and is related to the Escherichia coli tRNA gene argU

The gene fimU, located on a recombinant plasmid carrying the Salmonella typhimurium type 1 fimbrial gene cluster is closely related to the Escherichia coli tRNA gene argU. The fimU gene complements an E. coli argU mutant that is a P2 lysogen, thereby allowing the phage P4 to grow in this strain but preventing the growth of phage lambda. In addition, fimU was shown to be involved in fimbrial expression since transformants of the E. coli argU mutant could produce fimbriae only in the presence of fimU but not in its absence, whereas in an E. coli argU+ strain fimbriation did not require the fimU gene.

Liarozole inhibits human epidermal retinoic acid 4-hydroxylase activity and differentially augments human skin responses to retinoic acid and retinol in vivo

Metabolic inactivation of all-trans retinoic acid to 4-hydroxy retinoic acid occurs via a cytochrome P-450 enzyme. We investigated the effects of liarozole on the retinoic acid 4-hydroxylase activity of human epidermis and its ability to modify in vivo human skin responses to retinoic acid and all-trans retinol. Retinoic acid 4-hydroxylase activity induced in vivo by 4 d treatment with retinoic acid (0.1%) was inhibited in vitro by liarozole in a concentration-dependent manner. Comparable micromolar concentrations of liarozole were extracted from stratum corneum-free epidermis treated with 3% liarozole. Retinoic acid levels in liarozole-treated skin increased to 19 +/- 5 ng/g wet wt (mean +/- SEM, p < 0.002, n = 17) at 18 h and to 6 +/- 2 ng/g wet wt (p = 0.38, n = 17) at 48 h as compared to vehicle (not detectable). At 48 h, retinoic acid 4-hydroxylase activity was induced 9-fold over vehicle (p < 0.03, n = 8). At 96 h, no significant erythema or increased epidermal thickness was found when either retinoic acid (0.001%), all-trans retinol (0.0250%), or liarozole (3%) was applied individually, but when 0.001% retinoic acid and 3% liarozole were applied together, both erythema and increased epidermal thickness occurred. In contrast, 0.025% all-trans retinol and 3% liarozole together caused increased epidermal thickness but no erythema. These data demonstrate that, at doses used here, liarozole, although an effective inhibitor of retinoic acid 4-hydroxylase, cannot function alone like a retinoid in vivo, probably because of retinoic acid 4-hydroxylase induction. In the presence of a low dose retinoic acid or all-trans retinol, however, liarozole can amplify human skin responses to each retinoid in a manner characteristic of the retinoid at a higher dose (erythema and hyperplasia with retinoic acid; no erythema but hyperplasia with all-trans retinol).

Additive association of vitamin D insufficiency and sarcopenia with low femoral bone mineral density in noninstitutionalized elderly population: the Korea National Health and Nutrition Examination Surveys 2009-2010

Vitamin D insufficiency and sarcopenia are crucial risk factors for osteoporosis. In a study of noninstitutionalized elderly subjects, we investigated the simultaneous effect of vitamin D and sarcopenia on bone mineral density (BMD) and found that sarcopenia was associated with low BMD in the femur, especially in those with suboptimal vitamin D levels.

INTRODUCTION

Although vitamin D insufficiency and sarcopenia are prevalent in the elderly population worldwide, their possible influence on BMD has not been determined. We aimed to investigate the different effect of vitamin D insufficiency and sarcopenia on BMD in the elderly Korean population.

METHODS

Individuals aged 60 or older were selected from those who participated in the Fourth and Fifth Korea National Health and Nutrition Examination Surveys conducted in 2009 and 2010; 1,596 males and 1,886 females were analyzed. Appendicular skeletal muscle mass (ASM) and BMD were assessed by dual-energy X-ray absorptiometry; serum 25-hydroxyvitamin D [25(OH)D] and a panel of clinical and laboratory parameters were also measured.

RESULTS

The study population was divided into four groups according to their vitamin D and sarcopenic status. BMD in total femur and in the femoral neck but not the lumbar spine was markedly decreased in sarcopenic subjects with vitamin D insufficiency [25(OH)D < 20 ng/ml] comparing to other groups, regardless of gender. Multivariable linear regression models showed that BMD was significantly associated with ASM and high daily calcium intake as well as conventional risk factors such as age, body mass index (BMI), and history of fracture. Independent predictors for low femur BMD included sarcopenia, low daily calcium intake, low 25(OH)D levels, age, and BMI.

CONCLUSIONS

These data showed that an association between vitamin D insufficiency and low BMD was more prominent in elderly subjects with sarcopenia.

Osteoprotegerin inhibits in vitro mouse osteoclast formation induced by joint fluid from failed total hip arthroplasty

Osteoprotegerin (OPG) is a key regulator of osteoclastogenesis. We investigated the presence of OPG and bone-resorbing cytokines, the potential of osteoclastic differentiation in joint fluid from failed total hip arthroplasty (THA), and the inhibitory effect of OPG on osteoclast formation in vitro induced by the joint fluid. The study was aimed to clarify one important step in the cascade of periprosthetic osteolysis in the process of implant loosening. OPG levels in failed THA joint fluid of 20 cases were significantly lower than osteoarthritis (OA) joint fluid of 15 cases (p < 0.001). The levels of bone-resorbing cytokines, interleukin (IL)-1beta, and IL-6 were significantly higher in failed THA joint fluid than OA fluid (p < 0.001 and p = 0.001, respectively). Marked osteoclast formation was observed in the presence of failed THA joint fluid in the mouse coculture system, when compared to OA fluid (p < 0.001). The addition of 100 ng/mL OPG to the mouse coculture system completely inhibited osteoclast formation in the presence of failed THA joint fluid (p < 0.001). The data suggest that low levels of OPG combined with higher IL-1beta and IL-6 levels represent the potential of osteoclast differentiation and its activation in failed THA joint fluid. Inhibition of osteoclastogenesis in vitro by OPG suggests that a low level of OPG with elevated bone resorbing cytokines contributes to periprosthetic osteolysis via osteolytic joint fluid, thus leading to THA prosthesis loosening.

Free-electron lasers: present status and future prospects

Free-electron lasers as scientific instruments are reviewed. The present status and future prospects are delineated with attention drawn to the size, complexity, availability, and performance capability of this new tool.

Sodium-amino acid cotransport by type II alveolar epithelial cells

Type II alveolar epithelial cell monolayers have been shown to actively transport sodium (Na+). Coupling to amino acid uptake could be an important mechanism for Na+ entry into these cells. This study demonstrates the presence of such a coupled cotransport mechanism in the plasma membrane of isolated type II cells by use of the nonmetabolizable amino acid analogue alpha-methylaminoisobutyric acid (MeAIB). Transport of MeAIB in 137 mM Na+ is saturable, with the uptake constant (Vmax) equaling 13.9 pmol X mg prot-1 X s-1 and the Michaelis-Menten constant (Km) equaling 0.13 mM. In the presence of Na+, MeAIB is accumulated against a concentration gradient. MeAIB uptake in the absence of Na+ is linear with MeAIB concentration, as expected for simple diffusion. The Hill coefficient for Na+-MeAIB cotransport is 1.11, suggesting a 1:1 stoichiometry. Proline inhibits Na+-MeAIB cotransport, with Ki equaling 0.5 mM. These findings suggest that Na+-amino acid cotransport may be an important pathway for Na+ (and/or amino acid) uptake into type II alveolar epithelial cells.

KGF prevents hyperoxia-induced reduction of active ion transport in alveolar epithelial cells

We evaluated the effects of acute hyperoxic exposure on alveolar epithelial cell (AEC) active ion transport and on expression of Na+ pump (Na+-K+-ATPase) and rat epithelial Na+ channel subunits. Rat AEC were cultivated in minimal defined serum-free medium (MDSF) on polycarbonate filters. Beginning on day 5, confluent monolayers were exposed to either 95% air-5% CO2 (normoxia) or 95% O2-5% CO2 (hyperoxia) for 48 h. Transepithelial resistance (Rt) and short-circuit current (Isc) were determined before and after exposure. Na+ channel alpha-, beta-, and gamma-subunit and Na+-K+-ATPase alpha1- and beta1-subunit mRNA levels were quantified by Northern analysis. Na+ pump alpha1- and beta1-subunit protein abundance was quantified by Western blotting. After hyperoxic exposure, Isc across AEC monolayers decreased by approximately 60% at 48 h relative to monolayers maintained under normoxic conditions. Na+ channel beta-subunit mRNA expression was reduced by hyperoxia, whereas alpha- and gamma-subunit mRNA expression was unchanged. Na+ pump alpha1-subunit mRNA was unchanged, whereas beta1-subunit mRNA was decreased approximately 80% by hyperoxia in parallel with a reduction in beta1-subunit protein. Because keratinocyte growth factor (KGF) has recently been shown to upregulate AEC active ion transport and expression of Na+-K+-ATPase under normoxic conditions, we assessed the ability of KGF to prevent hyperoxia-induced changes in active ion transport by supplementing medium with KGF (10 ng/ml) from day 2. The presence of KGF prevented the effects of hyperoxia on ion transport (as measured by Isc) relative to normoxic controls. Levels of beta1 mRNA and protein were relatively preserved in monolayers maintained in MDSF and KGF compared with those cultivated in MDSF alone. These results indicate that AEC net active ion transport is decreased after 48 h of hyperoxia, likely as a result of a decrease in the number of functional Na+ pumps per cell. KGF largely prevents this decrease in active ion transport, at least in part, by preserving Na+ pump expression.

Diagnostic sensitivity of culture and drug resistance patterns in Korean patients with intestinal tuberculosis

SETTING

It is challenging to differentiate between intestinal tuberculosis (ITB) and Crohn's disease in areas where TB is still prevalent. The use of diagnostic tools and verifying the drug resistance patterns of ITB can be helpful for its correct diagnosis.

OBJECTIVE

To determine the diagnostic sensitivity of a culture assay using colonoscopic biopsy specimens and the drug resistance patterns of Mycobacterium tuberculosis isolated from ITB.

DESIGN

Data from 400 patients diagnosed with ITB were retrospectively analysed.

RESULTS

Of the 400 patients, 170 (42.5%) were males; the median age at diagnosis was 40 years. The sensitivity of culture was 44.1% (145/329). Resistance to at least one anti-tuberculosis drug was identified in 13 (17.6%) and multidrug-resistant TB (MDR-TB) was diagnosed in two (2.7%) of the 74 patients for whom drug susceptibility testing was performed. Including M. tuberculosis isolated from respiratory specimens, the proportion of MDR-TB was 4.4% (5/113); previous anti-tuberculosis treatment was an independent risk factor for MDR-TB (26.7% vs. 1.0%, P < 0.01).

CONCLUSION

Culture of colonoscopic biopsy specimens shows substantial diagnostic sensitivity; the frequency of MDR-TB is higher in previously treated cases than in new cases.

Joint fluid from patients with failed total hip arthroplasty stimulates pit formation by mouse osteoclasts on dentin slices

Periprosthetic bone resorption has been implicated in the failure of total joint arthroplasty. Osteolysis is reported to be associated with bone resorption induced by bone-resorbing cytokines, which are released from macrophages and fibroblasts in periprosthetic tissues after stimulation by wear debris generated in the joint cavity. Recent reports have suggested the concept of the effective joint space, which includes all periprosthetic regions that are accessible to joint fluid and wear debris. In this study, we examined the levels of interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), and tartrate-resistant acid phosphatase (TRAP) in joint fluid after failed total hip arthroplasty (THA) with osteolysis and investigated whether the joint fluid could activate osteoclastic bone resorption using unfractionated mouse bone cells cultured on dentin slices. Histochemical analysis showed the presence of more TRAP-positive cells in synovial capsules from failed THA patients when compared with osteoarthritis (OA) patients (controls). The levels of IL-6, sIL-6R, and TRAP in joint fluid from failed THA patients were significantly higher than in OA patients. Mouse osteoclasts cultured on dentin slices with joint fluid from failed THA patients with osteolysis produced a significant increase of pit area, whereas cells cultured with joint fluid from OA patients did not. Interestingly, osteoclastic bone resorption on dentin slices was significantly correlated with TRAP activity in joint fluid (p < 0.0001). These results suggest that joint fluid containing bone-resorbing cytokines is produced by synovial capsules in failed THA patients with osteolysis and may activate osteoclasts around the prosthesis in combination with those produced by interface tissues, thus contributing to periprosthetic bone resorption.

Epitopes on the S1 subunit of pertussis toxin recognized by monoclonal antibodies

To identify the neutralizing epitopes on the S1 subunit (A promoter) of pertussis toxin, we characterized anti-S1 monoclonal antibodies (MAbs) X2X5, 3CX4, and 6FX1. We confirmed by immunoblot analysis that these MAbs bind to the S1 subunit and not to the B oligomer of pertussis toxin and that they recognize different epitopes by a competitive binding enzyme-linked immunosorbent assay. These MAbs had differential abilities to neutralize the lymphocytosis-promoting factor activity of pertussis toxin in mice: 3CX4 and 6FX1 had partial neutralizing abilities, while MAb X2X5 had none. With these MAbs, the epitopes on the S1 subunit were examined by using trypsinized S1 peptides, recombinant truncated S1 molecules, and synthetic peptides. The non-neutralizing MAb X2X5 bound in immunoblots to tryptic peptides of various sizes as small as 1.5 kilodaltons; the neutralizing MAbs 3CX4 and 6FX1 bound only to a 24-kilodalton tryptic peptide band. Immunoblot studies with recombinant truncated S1 molecules demonstrated that amino acid residues 7 to 14 and 15 to 26 play an important role in the binding of neutralizing MAbs and the non-neutralizing MAb, respectively. The binding of these MAbs was not dependent upon the presence of C-terminal amino acid residues 188 to 234. To further define B-cell epitopes, the binding of the MAbs we tested to synthetic peptides representing the entire S1 subunit were examined. Neutralizing MAbs 3CX4 and 6FX1 bound to none of these peptides, further suggesting that these MAbs recognize conformational epitopes. The non-neutralizing MAb X2X5 bound to peptides 11 to 26 and 16 to 30, demonstrating that the major antigenic determinant recognized by this MAb is a linear epitope located within residues 16 to 26.

Blunt traumatic rupture of the diaphragm: sonographic diagnosis

Ultrasonographic features of seven patients with diaphragmatic rupture due to blunt trauma were analyzed. The ruptures occurred at the left hemidiaphragm in four patients and at the right in three. Direct ultrasonographic findings were as follows: disrupted diaphragm in four patients; nonvisualized diaphragm in three patients; floating diaphragm in two patients; and herniation of the liver or bowel loops through the diaphragmatic defect in three patients. Indirect sonographic findings included pleural effusion or subphrenic fluid collection in five patients and splenic laceration in one. Although the number of patients was limited, ultrasonography was very useful for the diagnosis of diaphragmatic rupture.

Permeability characteristics of primary cultured rabbit conjunctival epithelial cells to low molecular weight drugs

PURPOSE

To evaluate the permeability characteristics of primary cultured rabbit conjunctival epithelial cell (RCEC) layers to low molecular weight drugs of varying lipophilicity.

METHODS

3H-mannitol; hydrophilic sotalol and atenolol; moderately lipophilic metoprolol, timolol, propranolol; and highly lipophilic betaxolol were used as model compounds.

RESULTS

The conjunctival apparent permeability coefficient (Papp) of mannitol (1 x 10(-7) cm/s) was 2.4 times lower than that of the most hydrophilic beta-blocker, sotalol (Papp = 2.4 x 10(-7) cm/s). Differences in the degree of tightness of the epithelial cell layers brought about a 30-fold difference in the transport of atenolol in favor of the leaky cell layers, while not affecting the transport of the lipophilic drug, propranolol. Within the log partition coefficient (PC) range of -0.62 (sotalol) and 3.44 (betaxolol), there was a hundred-fold difference in the Papp. A sigmoidal curve was used to depict the influence of lipophilicity on solute permeation across conjunctival epithelial cell layers. An effective half-maximal Papp was observed at a log PC value of 1.2.

CONCLUSIONS

These findings on the lipophilicity effect on drug transport are generally similar to those reported for the isolated rabbit conjunctiva, suggesting the utility of cultured rabbit conjunctival epithelial cell layers as an in vitro model for evaluating drug transport.

Na(+)-dependent L-arginine transport in the pigmented rabbit conjunctiva

The objective of this study was to characterize Na(+)-coupled L-arginine (L-Arg) transport in the pigmented rabbit conjunctiva. The excised pigmented rabbit conjunctiva was mounted in the modified Ussing chamber for measurement of short-circuit current (Isc), 3H-L-arginine (3H-L-Arg) flux, and 22Na flux. L-Arg when added to the mucosal side led to 0.32-2.65 microA cm-2 increases in the Isc at 37 degrees C, but not at 4 degrees C or in a Na(+)-free solution. L-Arg at 1 mM stimulated net Na+ absorption by 0.12 microEq cm-2 h-1. The evidence for carrier-mediated transport of L-Arg includes: (1) temperature dependence and saturability over 0.01-10 mM, (2) Na+ dependence and ouabain sensitivity, (3) 84 +/- 2% reduction in the apparent permeability coefficient (Papp) of 3H-L-Arg in the presence of excess unlabeled L-Arg (1 mM), and (4) 16-fold difference in L-Arg transport (at 0.1 mM) between the mucosal-to-serosal and the serosal-to-mucosal direction. Moreover, L-Arg transport was inhibited by basic amino acids, large neutral amino acids, and nitric oxide synthase inhibitors, but not by acidic and small neutral amino acids. Kinetic analysis revealed the possible existence of both high and low affinity processes for L-Arg transport. A half maximal concentration (Km) and maximal L-Arg flux (Jmax) values of the low and high affinity processes were 5.90 and 0.07 mM, and 1,248 and 111 pmol cm-2 min-1, respectively. Hill analysis of L-Arg transport at 0.1 mM in the presence of varying Na+ concentrations in the mucosal bathing fluid yielded a Hill coefficient of 0.93, suggesting a 1:1 coupling between Na+ and L-Arg. In conclusion, Na(+)-coupled transport process(es) for L-Arg in accordance with a 1:1 stoichiometry appear to be present on the mucosal side of the pigmented rabbit conjunctiva. The pattern of inhibition by basic and large neutral amino acids and Na+ dependency are suggestive of system B0,(+)-mediated L-Arg transport.

Possible existence of Na(+)-coupled amino acid transport in the pigmented rabbit conjunctiva

The objective of the present study was to determine whether Na(+)-amino acid cotransport contributed to the short-circuit current (ISC) in the isolated pigmented rabbit conjunctiva. Glycine, L-arginine, D-arginine, and L-glutamic acid were the amino acids tested, and bioelectric measurements were made in the Using chamber. The ISC was increased from 4% (L-glutamic acid) to 44% (L-arginine). The EC50 was 0.35 mM for glycine, 0.06 mM for L-arginine, 0.16 mM for D-arginine, and 1 mM for L-glutamic acid. No elevation in ISC was seen in the absence of Na+ in the mucosal bathing fluid. The above findings are consistent with the possible existence of a Na(+)-amino acid cotransport process on the apical side of the pigmented rabbit conjunctiva.

The vesico-urethral pressuregram analysis of urethral function under stress

About one-third of older multiparous women are prone to stress urinary incontinence (SUI): unwanted urine loss during activities which suddenly raise intra-abdominal pressure. In this paper we describe and test a method for visualizing and analyzing the function of the urinary continence control system (CCS) under stress. Intravesical and intraurethral pressure changes from the resting state were recorded at proximal, mid-, and distal urethral locations during increasingly severe coughs and cross-plotted on a 'vesico-urethral pressuregram.' The slope (alpha) and intercept (chi zero) resulting from a linear regression analysis of these data were used to develop a continence equation which can be used to predict the equilibrium point pressure (PE): the intravesical pressure at which urine will leak to the intraurethral pressure recording site. We tested the null hypothesis that these parameters would not differ in six young, nulliparous continent women (mean +/- S.D. age: 30 +/- 3.5 yr) and six multiparous SUI women (52.3 +/- 8.0 yr, parity: 1.7 +/- 0.8), or between urethral locations. Significant differences in continence equation parameters were found between groups and in different urethral locations. In the SUI group static factors calculated from the term (1 - alpha) contributed 27% of the mean (S.D.) midurethral PE value, 145 (46) cm H2O, while dynamic factors, estimated from alpha, contributed 73% of this value. Valuable insights for improving the diagnosis and treatment of SUI may be obtained by analyzing the relative contributions of alpha and chi 0 to urethral closure during physical stress.

Staphylococcus lugdunensis--a potential pathogen in oral infection

OBJECTIVE

The purpose of this study was to investigate the pathogenicity of Staphylococcus lugdunensis in acute oral infection.

STUDY DESIGN

S. lugdunensis was isolated from patients with acute oral infections and from healthy control subjects. Antibiotic susceptibility, in vitro cellular toxicity, in vivo virulence, and hemolytic activity testing and dot blot analysis were performed. The statistical significance of in vitro cellular toxicity was determined by means of analysis of variance.

RESULTS

Isolated from the infected patients, S. lugdunensis showed resistance to penicillin, ampicillin, methicillin, cephalothin, and clindamycin, exhibited virulence in vivo, and showed delta-like hemolysin activity. Four of the 6 strains of S. lugdunensis gave synergistic hemolysis. In dot blot analysis, S. lugdunensis showed a positive reaction to the probe of the delta-hemolysin gene in S. aureus.

CONCLUSIONS

The results suggest that S. lugdunensis may be a potential pathogen in acute oral infection.

Analysis of microfiltration performance with constant flux processing of secondary effluent

This study involves the microfiltration (MF) of secondary effluent from a sequencing batch reactor processing industrial waste. The MF unit was a hollow fibre module with gas backwash capability, and operated with pumped permeate (controlled flux) and dead-end, crossflow or intermittent feed. The results showed that crossflow had no effect on flux and that intermittent dead-end filtration was less productive than non-intermittent operation. For dead-end filtration the cycle-time between gas backwashes depends very significantly on the imposed flux (varying from about 100 min at 30 L/m2 h to about 5 min at 90 L, m2 h) and the feed solids content. Optimal operation has to balance operating (energy for backwash) costs and the capital (membrane area) costs. Cost analysis based on capital and energy costs indicates that for lower energy cost the unit needs to be operated at lower imposed flux but to minimise total cost it is necessary to operate the unit above 60 L/m2 h imposed flux depending on the maximum transmembrane pressure (TMP) allowed before back washing. Further analysis of TMP profiles showed that membrane resistance increased over time towards a maximum, which tended to increase with imposed flux. This implies more frequent chemical cleaning for high flux operation. Specific cake resistances were deduced from the profiles and indicated cake compression at higher flux and larger maximum TMP. Results of long-term trials are also reported. Water quality analysis shows consistent quality of permeate

Differences in femoral neck geometry associated with age and ethnicity

SUMMARY

We studied femoral geometry in relation to age and ethnicity in a cross-sectional study. Age-associated cortical thinning showed the most pronounced effect, and Koreans studied here had thicker cortices and lower buckling ratios than those reported for other races. Cortical thickness may thus be a major determinant of hip fracture risk.

INTRODUCTION

The rate of hip fracture varies by age and ethnicity. The geometric properties of the femur influence femoral strength and fragility, but differences in femoral geometry according to age and ethnicity are poorly understood. To explain the high prevalence of hip fractures in the elderly and the relatively low hip fracture rate in Asian populations, we studied age-related changes and ethnic differences in femoral geometry.

METHODS

We recruited 214 peri- or postmenopausal women aged 46 to 85 years (mean age, 60.6 years). Their proximal femoral bone mineral densities (BMD) were measured by quantitative computed tomography and further analyzed geometric properties.

RESULTS

We observed large declines in trabecular volumetric bone mineral density associated with aging (33.03% less than the reference value in the oldest group, respectively). Cortical thickness decreased remarkably with age as well, and only 53.94% of the baseline value remained in the oldest group. As a result, the cortical buckling ratio increased geometrically and reached 239.14% of the reference value in the oldest group. In comparisons with other ethnic groups, Korean subjects had thicker cortices than their American, European, and African counterparts.

CONCLUSIONS

In this cross-sectional study, cortical thickness showed a pronounced age-associated decrease, and the cortical buckling ratio showed a strong age-associated increase. This may in part explain the higher rates of hip fractures in the elderly. When compared with other races, Asians had thicker cortical bone and lower buckling ratios, which may partially explain the lower prevalence of hip fractures in Asians.

Lithium-Battery Anode Gains Additional Functionality for Neuromorphic Computing through Metal-Insulator Phase Separation

Specialized hardware for neural networks requires materials with tunable symmetry, retention, and speed at low power consumption. The study proposes lithium titanates, originally developed as Li-ion battery anode materials, as promising candidates for memristive-based neuromorphic computing hardware. By using ex- and in operando spectroscopy to monitor the lithium filling and emptying of structural positions during electrochemical measurements, the study also investigates the controlled formation of a metallic phase (Li₇ Ti₅ O₁₂ ) percolating through an insulating medium (Li₄ Ti₅ O₁₂ ) with no volume changes under voltage bias, thereby controlling the spatially averaged conductivity of the film device. A theoretical model to explain the observed hysteretic switching behavior based on electrochemical nonequilibrium thermodynamics is presented, in which the metal-insulator transition results from electrically driven phase separation of Li₄ Ti₅ O₁₂ and Li₇ Ti₅ O₁₂ . Ability of highly lithiated phase of Li₇ Ti₅ O₁₂ for Deep Neural Network applications is reported, given the large retentions and symmetry, and opportunity for the low lithiated phase of Li₄ Ti₅ O₁₂ toward Spiking Neural Network applications, due to the shorter retention and large resistance changes. The findings pave the way for lithium oxides to enable thin-film memristive devices with adjustable symmetry and retention.

Generation of anti-type III pneumococcal polysaccharide hybridomas from mice with an X-linked B-lymphocyte defect

(CBA/N X BALB/c male)F1 mice bear on X-linked defect making them totally unresponsive to T-independent (TI), TI-2 antigens such as type III pneumococcal polysaccharide (SSS-III). We found that somatic cell hybrids between CB nonresponder spleen cells and NS1 plasmacytoma cells secreted antibody specific for SSS-III. The solid-phase binding of such antibody was completely inhibited by the addition of free antigen (SSS-III) and the amount of antibody detected in culture fluids ranged from 10 ng/ml to 10 micrograms/ml. Eight hybridoma clones were identified; all make antibody of the IgM class. These results indicate that the X-linked defect does not result in a deletion of a B-cell subset which responds to TI-2 antigens.

An exploratory study on cultural variations in oral health attitudes, behaviour and values of freshman (first-year) dental students

OBJECTIVE

To identify similarities and differences in oral health attitudes, behaviour and values among freshman dental students.

DESIGN

Cross-cultural survey of dental students.

SETTING

18 cultural areas.

PARTICIPANTS AND METHODS

904 first-year dental students completed the Hiroshima University-Dental Behavioural Inventory (HU-DBI) translated into their own languages. Individual areas were clustered by similarity in responses to the questions.

RESULTS

The first group displayed an 'occidental-culture orientation' with the exception of Brazil (Cluster 1 comprised: Australia, United Kingdom, Ireland, Belgium and Brazil, Cluster 2: Germany, Italy, Finland and France). The second group displayed an 'oriental-cultural orientation' with the exception of Greece and Israel (Cluster 3 comprised: China and Indonesia, and Cluster 4: Japan, Korea, Israel, Hong Kong, Malaysia, Thailand and Greece). Australia and United Kingdom were the countries that were most alike. Ireland was the 'neighbour' to these countries. Greece and Malaysia had similar patterns of oral health behaviour although geographic conditions are very different. Although it was considered that in Hong Kong, occidental nations have affected the development of education, it remained in the oriental-culture group. Comparison with the data from the occidentals indicates that a higher percentage of the orientals put off going to the dentist until they have toothache (p < 0.001). Only a small proportion of the occidentals (8%) reported a perception of inevitability in having false teeth, whereas 33% of the orientals held this fatalistic belief (p = 0.001).

CONCLUSIONS

Grouping the countries into key cultural orientations and international clusters yielded plausible results, using the HU-DBI.