Neuroanatomical and morphometric study of S100β positive astrocytes in the entorhinal cortex during ageing in the 3xTg-Alzehimer's disease mouse model

Astrocytes contribute to the progression of neurodegenerative diseases, including Alzheimer's disease (AD). Here, we report the neuroanatomical and morphometric analysis of astrocytes in the entorhinal cortex (EC) of the aged wild type (WT) and triple transgenic (3xTg-AD) mouse model of AD. Using 3D confocal microscopy, we determined the surface area and volume of positive astrocytic profiles in male mice (WT and 3xTg-AD) from 1 to 18 months of age. We showed that S100β-positive astrocytes were equally distributed throughout the entire EC in both animal types and showed no changes in Nv (number of cells/mm3) nor in their distribution at the different ages studied. These positive astrocytes, demonstrated an age-dependent gradual increase in their surface area and in their volume starting at 3 months of age, in both WT and 3xTg-AD mice. This last group demonstrated a large increase in both surface area and volume at 18 months of age when the burden of pathological hallmarks of AD is present (69.74% to 76.73% in the surface area and the volume, for WT and 3xTg-AD mice respectively). We observed that these changes were due to the enlargement of the cell processes and to less extend the somata. In fact, the volume of the cell body was increased by 35.82% in 18-month-old 3xTg-AD compared to WT. On the other hand, the increase on the astrocytic processes were detected as soon as 9 months of age where we found an increase of surface area and volume (36.56% and 43.73%, respectively) sustained till 18 month of age (93.6% and 113.78%, respectively) when compared age-matched non-Tg mice. Moreover, we demonstrated that these hypertrophic S100β-positive astrocytes were mainly associated with Aβ plaques. Our results show a severe atrophy in GFAP cytoskeleton in all cognitive areas; whilst within the EC astrocytes independent to this atrophy show no changes in GS and S100β; which can play a key role in the memory impairment.

MPK12 in stomatal CO2 signaling: function beyond its kinase activity

Protein phosphorylation is a major molecular switch involved in the regulation of stomatal opening and closure. Previous research defined interaction between MAP kinase 12 and Raf-like kinase HT1 as a required step for stomatal movements caused by changes in CO₂ concentration. However, whether MPK12 kinase activity is required for regulation of CO₂ -induced stomatal responses warrants in-depth investigation. We apply genetic, biochemical, and structural modeling approaches to examining the noncatalytic role of MPK12 in guard cell CO₂ signaling that relies on allosteric inhibition of HT1. We show that CO₂ /HCO₃ ^- -enhanced MPK12 interaction with HT1 is independent of its kinase activity. By analyzing gas exchange of plant lines expressing various kinase-dead and constitutively active versions of MPK12 in a plant line where MPK12 is deleted, we confirmed that CO₂ -dependent stomatal responses rely on MPK12's ability to bind to HT1, but not its kinase activity. We also demonstrate that purified MPK12 and HT1 proteins form a heterodimer in the presence of CO₂ /HCO₃ ^- and present structural modeling that explains the MPK12:HT1 interaction interface. These data add to the model that MPK12 kinase-activity-independent interaction with HT1 functions as a molecular switch by which guard cells sense changes in atmospheric CO₂ concentration.

Stomatal CO2/bicarbonate sensor consists of two interacting protein kinases, Raf-like HT1 and non-kinase-activity requiring MPK12/MPK4

The continuing rise in the atmospheric carbon dioxide (CO₂) concentration causes stomatal closing, thus critically affecting transpirational water loss, photosynthesis, and plant growth. However, the primary CO₂ sensor remains unknown. Here, we show that elevated CO₂ triggers interaction of the MAP kinases MPK4/MPK12 with the HT1 protein kinase, thus inhibiting HT1 kinase activity. At low CO₂, HT1 phosphorylates and activates the downstream negatively regulating CBC1 kinase. Physiologically relevant HT1-mediated phosphorylation sites in CBC1 are identified. In a genetic screen, we identify dominant active HT1 mutants that cause insensitivity to elevated CO₂. Dominant HT1 mutants abrogate the CO₂/bicarbonate-induced MPK4/12-HT1 interaction and HT1 inhibition, which may be explained by a structural AlphaFold2- and Gaussian-accelerated dynamics-generated model. Unexpectedly, MAP kinase activity is not required for CO₂ sensor function and CO₂-triggered HT1 inhibition and stomatal closing. The presented findings reveal that MPK4/12 and HT1 together constitute the long-sought primary stomatal CO₂/bicarbonate sensor upstream of the CBC1 kinase in plants.

Mitogen-activated protein kinases MPK4 and MPK12 are key components mediating CO2 -induced stomatal movements

Respiration in leaves and the continued elevation in the atmospheric CO2 concentration cause CO2 -mediated reduction in stomatal pore apertures. Several mutants have been isolated for which stomatal responses to both abscisic acid (ABA) and CO2 are simultaneously defective. However, there are only few mutations that impair the stomatal response to elevated CO2 , but not to ABA. Such mutants are invaluable in unraveling the molecular mechanisms of early CO2 signal transduction in guard cells. Recently, mutations in the mitogen-activated protein (MAP) kinase, MPK12, have been shown to partially impair CO2 -induced stomatal closure. Here, we show that mpk12 plants, in which MPK4 is stably silenced specifically in guard cells (mpk12 mpk4GC homozygous double-mutants), completely lack CO2 -induced stomatal responses and have impaired activation of guard cell S-type anion channels in response to elevated CO2 /bicarbonate. However, ABA-induced stomatal closure, S-type anion channel activation and ABA-induced marker gene expression remain intact in the mpk12 mpk4GC double-mutants. These findings suggest that MPK12 and MPK4 act very early in CO2 signaling, upstream of, or parallel to the convergence of CO2 and ABA signal transduction. The activities of MPK4 and MPK12 protein kinases were not directly modulated by CO2 /bicarbonate in vitro, suggesting that they are not direct CO2 /bicarbonate sensors. Further data indicate that MPK4 and MPK12 have distinguishable roles in Arabidopsis and that the previously suggested role of RHC1 in stomatal CO2 signaling is minor, whereas MPK4 and MPK12 act as key components of early stomatal CO2 signal transduction.

Results of an international comparison of activity measurements of 68Ge

An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a 68Ge/68Ga solution. Results for the activity concentration, CA, of 68Ge at a reference date of 12h00 UTC 14 November 2014 were submitted by 17 laboratories, encompassing many variants of coincidence methods and liquid-scintillation counting methods. The first use of 4π(Cherenkov)β-γ coincidence and anticoincidence methods in an international comparison is reported. One participant reported results by secondary methods only. Two results, both utilizing pure liquid-scintillation methods, were identified as outliers. Evaluation using the Power-Moderated Mean method results in a proposed Comparison Reference Value (CRV) of 621.7(11)kBqg-1, based on 14 results. The degrees of equivalence and their associated uncertainties are evaluated for each participant. Several participants submitted 3.6mL ampoules to the BIPM to link the comparison to the International Reference System (SIR) which may lead to the evaluation of a Key Comparison Reference Value and associated degrees of equivalence.

Pre-operative serum albumin level substantially predicts post-operative morbidity and mortality among patients with colorectal cancer who undergo elective colectomy

The quantitative relationship between serum albumin level and surgical outcomes has not been clearly established. This study included 3732 patients with colon cancer who underwent a potentially curative colectomy. Post-operative mortality and morbidity were analysed according to the patients' demographic data, pre-operative comorbidities, and tumour-related factors. Age, asthma, renal impairment, and albumin level were significantly associated with post-operative morbidity and mortality in the multivariate analyses. Logistic regression analysis revealed linear relationships of post-operative morbidity and mortality with albumin level. The morbidity and mortality rates decreased by 7.3% and 15.6%, respectively, for each 0.1 g/dL increase in albumin level. This finding remained significant in the hypoalbuminaemia subgroup but not in the normoalbuminaemia subgroup. That is, the morbidity and mortality rates significantly decreased by 8.7% and 17.7%, respectively (both P < 0.001), in the former group and decreased by 2.7% (P = 0.112) and 11.6% (P = 0.092), respectively, in the latter group. This study demonstrated that serum albumin level linearly predicted the post-operative morbidity and mortality among the colorectal cancer patients. Pre-operative serum albumin level may therefore be used as a continuous rather than a categorical marker of disease severity, especially among patients with hypoalbuminaemia.

Design and testing of a uniformly solar energy TIR-R concentration lenses for HCPV systems

In this paper, total internal reflection-refraction (TIR-R) concentration (U-TIR-R-C) lens module were designed for uniformity using the energy configuration method to eliminate hot spots on the surface of solar cell and increase conversion efficiency. The design of most current solar concentrators emphasizes the high-power concentration of solar energy, however neglects the conversion inefficiency resulting from hot spots generated by uneven distributions of solar energy concentrated on solar cells. The energy configuration method proposed in this study employs the concept of ray tracing to uniformly distribute solar energy to solar cells through a U-TIR-R-C lens module. The U-TIR-R-C lens module adopted in this study possessed a 76-mm diameter, a 41-mm thickness, concentration ratio of 1134 Suns, 82.6% optical efficiency, and 94.7% uniformity. The experiments demonstrated that the U-TIR-R-C lens module reduced the core temperature of the solar cell from 108 °C to 69 °C and the overall temperature difference from 45 °C to 10 °C, and effectively relative increased the conversion efficiency by approximately 3.8%. Therefore, the U-TIR-R-C lens module designed can effectively concentrate a large area of sunlight onto a small solar cell, and the concentrated solar energy can be evenly distributed in the solar cell to achieve uniform irradiance and effectively eliminate hot spots.

Increased densities of resting and activated microglia in the dentate gyrus follow senile plaque formation in the CA1 subfield of the hippocampus in the triple transgenic model of Alzheimer's disease

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that is characterised by the presence of β-amyloid (Aβ) plaques, neurofibrillary tangles (NFTs) and synaptic loss specifically in brain regions involved in learning and memory such as the neocortex and the hippocampus. Aβ depositions in the form of neuritic plaques trigger activation of microglia that is believed to be a common neuropathological feature of AD brains. As an integral part of the hippocampus, the dentate gyrus (DG) plays an important role in cognitive function. Although post-mortem studies suggest later involvement of the DG into the AD progression, changes in microglia have not been studied in this subfield of the hippocampus. In the present study the numerical density (Nv, #/mm(3)) of both resting (identified by tomato lectin staining) and activated (identified by Mac-1 immunoreactivity) microglia was analysed in the molecular layer (ML) of the DG in the triple transgenic (3xTg-AD) mouse model of AD at different ages (9, 12 and 18 months). The 3xTg-AD mouse model of AD showed a significant increase in the Nv of resting (by 75%) and activated (by 67%) at 18 months of age compared to non-Tg controls. These results indicate a complex microglial remodelling during AD progression.

Topology of feather melanocyte progenitor niche allows complex pigment patterns to emerge

Color patterns of bird plumage affect animal behavior and speciation. Diverse patterns are present in different species and within the individual. Here, we study the cellular and molecular basis of feather pigment pattern formation. Melanocyte progenitors are distributed as a horizontal ring in the proximal follicle, sending melanocytes vertically up into the epithelial cylinder, which gradually emerges as feathers grow. Different pigment patterns form by modulating the presence, arrangement, or differentiation of melanocytes. A layer of peripheral pulp further regulates pigmentation via patterned agouti expression. Lifetime feather cyclic regeneration resets pigment patterns for physiological needs. Thus, the evolution of stem cell niche topology allows complex pigment patterning through combinatorial co-option of simple regulatory mechanisms.

Population dose from medical diagnostic exposure in Taiwan

Medical exposure showed a continuous increasing trend. This trend was due to the growth of diagnostic procedures such as computed tomography (CT) and interventional fluoroscopy (IVF). In the present work, results of a recent study on medical exposure in Taiwan are reported. This study analysed data from the National Health Insurance Research Database. Surveyed data on the dose indices, including the entrance surface dose in radiography, dose area product in fluoroscopy, CT dose index in CT and mean glandular dose in mammography, were applied. Using programmes and databases, dose indices were converted to the effective dose. For the year 2008, individual effective doses in Taiwan were estimated as 0.16, 0.37, 0.12 and 0.12 mSv for conventional radiography and fluoroscopy, CT, IVF and nuclear medicine, respectively. The total collective effective dose and the effective dose per individual for medical exposure were 17 788 person-Sv and 0.77 mSv, respectively.

Natural frequency assessment of stability of root keeper magnetic devices

The aim of the study was to evaluate the potential for using natural frequency (NF) as an indicator for assessing the stability of a magnetic keeper device used in prosthodontic treatment. A three-dimensional finite element (FE) model of a root keeper-cement-dentine system was established for NF analysis. The model was first validated against a series of in vitro experiments. Then, NF values of the first vibrational mode of the FE model with various boundary conditions were calculated. The in vitro results showed that the measured NF values of the root keeper-incisor units decreased significantly (p<0.01) from 9.07 +/- 0.37 to 5.73 +/- 0.10 kHz when the units were embedded in simulated bony tissue. Results obtained from FE simulations demonstrated that the root keeper would fully loosen when the constant values of the spring elements were lower than 10(4) N-m(-1). Furthermore, a linear increase in the NF values of the model was observed from 6.16 to 15.52 kHz, when the constant was increased from 10(4) to 10(7) N-m(-1), and the values then reached a plateau. The results indicate that the NF value of a root keeper has the potential to be used for monitoring the stability of such a device.

Electromyographic findings of paradoxical puborectalis contraction correlate poorly with cinedefecography

BACKGROUND

Both intra-anal sponge electromyography (SEMG) and needle electromyography (NEMG) are used to diagnose paradoxical puborectalis contraction (PPC). The aim of this retrospective study was to assess the correlation among SEMG and NEMG and cinedefecography (CD) in the diagnosis of PPC.

METHODS

Between 1992 and 1999, a total of 261 constipated patients underwent both CD and EMG: 64 had NEMG while 197 had SEMG. PPC was diagnosed by EMG when there was failure to achieve a significant decrease in electrical activity of the puborectalis muscle during attempted evacuation. CD criteria for PPC included lack of straightening of the anorectal angle or persistence of the puborectalis impression during evacuation. CD was considered diagnostic and EMG results were thus compared with those of CD. Agreement was calculated using the kappa statistics (kappa) for concordance.

RESULTS

Both NEMG and SEMG had low positive predictive rates (33% in NEMG, 28% in SEMG) and high negative predictive rates (91% in NEMG, and 78% in SEMG) when correlated with CD findings. Agreement between NEMG and CD was noted in 46 of 64 patients (72%, kappa=0.274) while there was agreement between SEMG and CD in 120 of 197 patients (61%; kappa=0.067); p>0.05 needle vs. sponge.

CONCLUSION

Although both NEMG and SEMG have a low positive predictive values, they have high negative predictive value for PPC. Therefore, neither NEMG nor SEMG alone are optimal tests for diagnosing the presence of PPC.

Psychiatric morbidity and post-traumatic symptoms among survivors in the early stage following the 1999 earthquake in Taiwan

This study reports the clinical psychiatric presentations and post-traumatic symptoms among 525 survivors at Yu-Chyr District in Nantou County who sought psychiatric service in the first month following the devastating earthquake that struck the central area of Taiwan. All subjects received psychiatric interviews and assessments using the 12-item Chinese Health Questionnaire (CHQ-12) and a checklist for post-traumatic symptoms. The most common psychiatric symptoms reported were insomnia, palpitations, nervousness, and dizziness with headache. Eleven percent of the subjects reported having thought of death or having suicidal ideation. The mean score on the CHQ-12 was 6.43 (S.D.=2.89). The rate of probable psychiatric morbidity as defined by a CHQ-12 score > or =3 was 89.9%. Post-traumatic symptoms were very prevalent, particularly symptoms of re-experiencing the earthquake and hyper-arousal. Factors significantly associated with high psychiatric morbidity were being female, serious destruction of property and house, and personality characteristics of nervousness and obsessiveness. Findings of this study suggest that early psychiatric intervention, including pharmacological treatment for acute stress disorder, is indicated during the early stages following a disastrous earthquake.

Natural frequency analysis of periodontal conditions in human anterior teeth

The purpose of this study was to evaluate the possibility of using natural frequency (NF) analysis to detect the attachment loss of periodontal tissue. In this study, 698 anterior teeth were examined by a conventional probing method and also by NF analysis. The teeth were triggered to vibrate with an impulse hammer, and the vibrational response was detected by an acoustic sensor. Our results demonstrate no significant difference in NF values between the upper-lower/left-right quadrants of the tested teeth, although the mean natural frequency value of central incisors with periodontal disease was found to be 1.24 +/- 0.11 kHz which is significantly lower than that of teeth in a healthy condition (1.34 +/- 0.20kHz; p < 0.01). On the other hand, the mean frequency for periodontal disease involving canines (1.28 +/- 0.09 kHz) was also significantly lower than the corresponding value for healthy analogs (1.35 +/- 0.17 kHz; p < 0.05). These results suggest that NF analysis appears to be an effective method for assessing the periodontal condition of anterior teeth. Moreover, since this method is noninvasive, nondestructive, and necessitates minimal tooth contact, it can serve as an effective method for the early quantifiable testing and prevention of periodontal disease.

Association of sex, adiposity, and diet with HDL subclasses in middle-aged Chinese

BACKGROUND

There is limited information regarding the associations of lifestyle factors and sex with HDL subclasses containing apolipoprotein (apo) A-I (Lp A-I) and both apo A-I and apo A-II (Lp A-I:A-II).

OBJECTIVE

We sought to examine the relations between 2 major HDL subclasses and sex, menopausal status, nutrient intakes, and adiposity.

DESIGN

We conducted interviews and measured blood variables in 409 government employees aged 40-59 y in Taiwan.

RESULTS

Women (n = 203) had significantly higher concentrations of HDL cholesterol, Lp A-I, and Lp A-I:A-II than did men (n = 206). Postmenopausal women (n = 72) had higher concentrations of HDL cholesterol, Lp A-I, and Lp A-I:A-II than did premenopausal women (n = 131). Body mass index and waist-to-hip ratio were strong predictors of and exerted an independent additive effect on Lp A-I concentrations in both men and women. However, body adiposity was associated with Lp A-I:A-II concentrations only in men. Waist-to-hip ratio was an independent determinant of Lp A-I but not of Lp A-I:A-II in men and postmenopausal women after adjustment for age, body mass index, smoking, and diet. Although there were relatively weak associations between dietary factors and both HDL subclasses (r = 0.01-0.26) in men and women according to bivariate analyses, multiple regression models showed that total fat, saturated fat, and cholesterol intakes were significantly correlated with HDL cholesterol and both Lp A-I and Lp A-I:A-II in men, but not in women.

CONCLUSION

Our data suggest that body adiposity and dietary fat consumption affect 2 major HDL subclasses differently depending on subject sex and menopausal status.

Prospective study comparing wounds closed with tape with sutured wounds in colorectal surgery

HYPOTHESIS

To test the efficacy of adhesive paper tape in the closure of clean-contaminated wounds following elective colorectal resection.

DESIGN

A prospective, nonrandomized controlled study.

SETTING

A medical center that offers a mixture of primary, secondary, and tertiary care services.

PATIENTS

The group undergoing skin closure with paper tape (PT group) consisted of 150 patients. The group undergoing skin closure with interrupted suture (IS group) also comprised 150 patients. All 300 patients underwent elective colorectal resection in 1997.

MAIN OUTCOME MEASURES

The duration of skin closure, wound complication rate, and cosmetic appearance of the scar at 6 months after operation were compared using the chi(2)test or t test.

RESULTS

The mean +/- SD average duration of skin closure was 116 +/- 23 seconds for the PT group and 457 +/- 64 seconds for the IS group (P<.01). The wound complication rate was 3.3% (3 cases with wound infection; 2 with wound separation) for the PT group and 3.3% (5 cases with wound infection) for the IS group (P = 1.0). No significant differences were found between the narrowest width (mean +/- SD, 2.2 +/- 0.9 mm vs 2.3 +/- 1.0 mm) and widest width (mean +/- SD, 4.7 +/- 2.0 mm vs 4.3 +/- 1.8 mm) of scar formation between the 2 groups at 6 months after the operation. Ninety-eight percent of patients in the PT group reported satisfaction with their scar, compared with 92% in the IS group (P =.03).

CONCLUSION

Compared with the traditional suture method, paper tape closure in the treatment of clean-contaminated wounds was less time consuming and produced greater patient satisfaction with no increased rate of wound complications.

Effects of a single session of prolonged muscle stretch on spastic muscle of stroke patients

The control of spasticity is often a significant problem in the management of patients with spasticity. The aim of this study was to evaluate the effect of a single session of prolonged muscle stretch (PMS) on the spastic muscle. Seventeen patients with spastic hemiplegia were selected to receive treatment. Subjects underwent PMS of the triceps surae (TS) by standing with the feet dorsiflexed on a tilt-table for 30 minutes. Our test battery consisted of four measurements including the modified Ashworth scale of the TS, the passive range of motion (ROM) of ankle dorsiflexion, the H/M ratio of the TS, and the F/M ratio of the tibialis anterior (TA). The results indicated that the passive ROM of ankle dorsiflexion increased significantly (p < 0.05) compared to that before PMS treatment. Additionally, PMS reduced motor neuron excitability of the TS and significantly increased that of the TA (p < 0.05). These results suggest that 30 minutes of PMS is effective in reducing motor neuron excitability of the TS in spastic hemiplegia, thus providing a safe and economical method for treating stroke patients.

Factors influencing the dynamic behaviour of human teeth

Modal analysis is carried out to test the natural frequencies of certain human teeth, including central incisors (CIs), canines (CAs), first premolars (FPs) and first molars (FMs). A total number of 1007 teeth are tested, taking into account tooth type, oral location, age and gender, to analyse the effects of the above-mentioned factors on the natural frequency of the sample teeth. The results reveal that no significant difference in the natural frequency is noted among teeth in the four different intra-oral quadrants. Nevertheless, tooth type and age elicit an effect upon the value of the natural frequency of teeth. On the other hand, the mean value for the natural frequency of CIs (1.27 +/- 0.15 kHz), CAs (1.30 +/- 0.15 kHz), FPs (1.27 +/- 0.15 kHz) and FMs (1.16 +/- 0.12 kHz) for males are significantly lower (p < 0.01) than the analogous figure for females (1.41 +/- 0.21 kHz for CIs, 1.40 +/- 0.18 kHz for CAs, 1.37 +/- 0.20 kHz for FPs, and 1.25 +/- 0.16 kHz for FMs). Moreover, the natural frequency of teeth in male subjects varies with age (p < 0.05). The highest mean frequency of CIs, CAs and FPs for the male subjects is found for the group aged between 40 and 49 years. On the other hand, the natural frequency for the similar set of teeth for the female subjects is shown to be in no way associated with age.

Mussel watch: a review of Cu and other metals in various marine organisms in Taiwan, 1991-98

This study presents the distribution of Cu, Zn, Pb, Cd, Hg and As in various marine organisms collected along the western coast of Taiwan from 1991 to 1998, and also evaluates the time variation of Cu in oysters before (1980-85) and after (1986-98) the "green oyster" incident. The results show that relatively high geometric mean (GM) concentrations of Cu, Zn, Pb, Cd, As and Hg were generally found in Crassostrea gigas (Cu=229 microg/g, Zn=783 microg/g), Gomphina aeguialtera (Pb=30.3 microg/g), Tegillarca granosa (Cd=2.85 microg/g), Thais clavigera (As=96.9 microg/g) and Parapenaeopsis cornuta (Hg=1.35 microg/g), respectively. Especially, maximum Cu and Zn concentrations (GM=229 and 783 microg/g, respectively) in oysters (C. gigas) from different culture areas were much higher than those of the other organisms by about 1.13-458 and 2.40-63.7 times, respectively. Similarly, rock-shells (Thais clavigera) had a high capacity for accumulating Cu (GM=202 microg/g) and Zn (GM=326 microg/g) under the same physico-chemical conditions. The highest GM Cu and Zn concentrations of 1108 (range from 113 to 2806) and 1567 (range from 303 to 3593) microg/g were obtained in oysters from the Hsiangshan coastal area, one of the most important oyster culture areas in Taiwan. However, the highest GM Cd and As concentrations of 6.82 and 19.3 microg/g were found in oysters from the Machu Islands. Mean Cu concentrations in the oysters from the Erhjin Chi estuary declined from 2194+/-212 microg/g in 1986-90 to 545 microg/g (GM) in 1991-96. In the Hsiganshan area, GM Cu concentrations of 909 microg/g (1991-96) and 1351 microg/g (1997-98) in oysters were significantly higher than those of 201 microg/g (1980-85) and 682 microg/g (1986-90). The gradually increasing levels of Cu and Zn in the oysters from the Hsiangshan area have been observed year by year.

Surgical outcome after curative resection of rectal leiomyosarcoma

PURPOSE

The aim of this study is to present the prognosis and possible associated prognostic factors after curative resection of rectal leiomyosarcoma.

METHODS

From 1979 to 1996 our hospital saw 40 patients with rectal leiomyosarcoma, including 19 females, who did not have metastasis initially and received curative resection and regular postoperative follow-up.

RESULTS

The mean age of the 40 patients was 58.7 years. Anal bleeding and perianal pain were the two most common symptoms at initial diagnosis. Twenty-nine patients received a radical surgical resection, such as abdominoperineal resection or low anterior resection; the other 11 patients received a wide local excision, such as transrectal excision or Kraske's operation. Sixteen tumors were classified as high-grade leiomyosarcoma, and 23 as low grade. Nineteen patients (48 percent) developed recurrence or metastasis postoperatively (median follow-up, 35 months). The overall and disease-free (1-year, 3-year, and 5-year) survival rates were 97, 90, and 75 percent and 90, 59, and 46 percent, respectively. In univariate analysis, younger group (<50 years, n = 9, P = 0.033) and high-grade leiomyosarcoma (P = 0.043) showed poorer prognosis in the disease-free survival curve. In the multivariate Cox model, gender, tumor size, tumor location, and operation type did not significantly affect disease-free survival, whereas histologic grade (P = 0.037) and age divided by a level of 50 years (P = 0.009) were shown to be independent factors. There was a strong trend toward higher local recurrence rate for the wide local excision group than for the radical resection group (55 vs. 24 percent, P = 0.067) despite the wide local excision group being composed of smaller tumors (5.1 vs. 7.5 cm, P = 0.069). There was no difference in the incidence of distant metastasis between the two groups with different operation types. The metastasis rates of the wide local excision and radical resection groups were 27 and 38 percent, respectively.

CONCLUSION

A younger age (<50 years) and a high histologic grade of tumor were the two most significant poor prognostic factors for rectal leiomyosarcoma. Radical resection may be superior to wide local excision in the prevention of local recurrence but not distant metastasis.

Identification of a fibronectin binding protein from Streptococcus mutans

The interaction of viridans streptococci with components of the extracellular matrix (ECM) plays an important role in the pathogenesis of infective endocarditis. We have identified a surface protein of Streptococcus mutans which binds the ECM constituent fibronectin (Fn). Initially, we found that S. mutans could adsorb soluble Fn in plasma, but with lower efficiency than Streptococcus pyogenes. In addition, S. mutans could bind immobilized Fn in a dose-dependent manner when tested using an enzyme-linked immunosorbent assay. Crude extracts of cell wall-associated proteins or extracellular proteins from S. mutans MT8148 specifically bound Fn through a protein with the molecular mass of ca. 130 kDa, as detected by far-Western immunoblotting. The candidate Fn binding protein (FBP-130) was purified to near homogeneity by using Fn coupled Sepharose 4B affinity column chromatography. A rabbit polyclonal antibody against FBP-130 reacted specifically with a protein of molecular mass of ca. 130 kDa in both cell wall and extracellular fractions, and the abundance of FBP was higher in the former than in the latter fractions. The purified FBP bound specifically to immobilized Fn, whereas the binding of soluble Fn to coated FBP could only be detected in the presence of high concentrations of Fn. The purified FBP, as well as anti-FBP immunoglobulin G, inhibited the adherence of S. mutans to immobilized Fn and endothelial cells (ECV304) in a dose-dependent manner. These results demonstrated that FBP-130 mediated the adherence of S. mutans specifically to Fn and endothelial cells in vitro. The characteristics of S. mutans and FBP-130 in binding Fn confirmed that viridans streptococci adopt different strategies in their interaction with ECM.

Anterior ankle-foot orthosis effects on postural stability in hemiplegic patients

OBJECTIVES

To evaluate the effects of an anterior ankle-foot orthosis (AFO) on static and dynamic postural stability in hemiplegic patients.

DESIGN

A cross-sectional assessment of hemiplegic subjects with and without an AFO.

SETTING

Outpatient department of a rehabilitation hospital.

PATIENTS

A convenience sample of 24 subjects who had been prescribed an anterior AFO.

OUTCOME MEASURES

Postural sway index and postural symmetry (body weight distribution through the affected leg) when standing were measured as static postural stability. Maximal balance range in anterior-posterior and lateral directions and the affected leg's weight bearing after weight shift to affected side were measured as dynamic postural stability.

RESULTS

When wearing the anterior AFO, there was no significant difference and small effect size (r<0.3) in postural sway index (p = .35), postural symmetry (p = .21), and maximal balance range in anterior-posterior direction (p = .46). There was a significant improvement and large effect size (r>0.5) in lateral weight shifting (p<.01) and weight bearing through the affected leg after weight shifted to the affected side (p<.01).

CONCLUSIONS

The significant effects of the anterior AFO in long-term hemiplegic patients were on lateral weight shifting and weight bearing through affected leg after weight shifted to the affected side. Postural sway, postural symmetry, and anterior-posterior weight shifting were not significantly affected.

Prognostic value of anti-Epstein-Barr virus antibodies in nasopharyngeal carcinoma (NPC)

INTRODUCTION

Epstein-Barr virus (EBV) is a ubiquitous human herpes virus with worldwide infection. It is associated with Burkitt's lymphoma in Africa and nasopharyngeal cancer (NPC) in Asian countries. EBV-coded DNA was found to be present in epithelial elements of NPC, and is usually associated with non-keratinizing (WHO type II) or undifferentiated carcinoma (WHO type III). Transcriptional analyses of EBV genome expression in NPC demonstrate an activated viral state in some of these tumors, leading to elevated levels of serum anti-viral capsid antigen (VCA) antibody in NPC patients.

METHODS

Eighty patients with histological diagnoses of NPC according to the 1978 WHO classification were referred to the Department of Radiation Oncology at Chang-Hua Christian Hospital for curative radiotherapy from 1985 to 1995. The patients were staged according to the AJCC staging system. A mean dose of 7,020 cGy in 39 fractions was delivered to the primary tumor using a telecobalt-60 unit or 6-10 MV X-ray linear accelerator. Pre- and postradiotherapy serum levels of anti-EBV/VCA IgG and IgA were determined for all patients using the indirect immunoperoxidase assay (IPA). Multivariate analysis was done to determine which factors affected the patients' treatment outcome and survival.

RESULTS

Five patients were excluded from this study due to incomplete radiotherapy, leaving 75 patients eligible for analysis. Overall local control was 77.3%, with a mean disease-free interval of 19.7 months. Factors affecting local control included radiation dose and pretreatment anti-EBV/VCA IgG titer. The overall 5-year actuarial survival for the 75 patients was 75%, with a median survival of 129.5 months. The 5-year actuarial survival rates for stage I + II, III, and IV patients were 90%, 40%, and 45%, respectively. Prognostic factors for survival included tumor histological type and pretreatment anti-EBV/VCA IgA titer, while prognostic factors for local control included total radiation dose received and pretreatment anti-EBV/VCA IgG titer.

CONCLUSION

We found that there was a significant difference in the geometric mean titer of anti-EBV/VCA IgA antibodies before and after radiotherapy. Prognostic factors affecting NPC patients' actuarial survival included tumor histology and pretreatment IgA titer, while prognostic factors for local control of NPC included total radiation dose received and pretreatment IgG titer.

Stapled colonic J-pouch-anal anastomosis without a diverting colostomy for rectal carcinoma

PURPOSE

Colonic J-pouch reconstruction is designed to improve functional outcome of coloanal anastomosis. Most surgeons use a diverting colostomy to avoid severe pelvic sepsis caused by anastomotic breakdown.

METHODS

We report the outcome of 30 consecutive patients with colonic J-pouch-anal anastomosis without a diverting colostomy performed between November 1992 and October 1993. All patients had carcinoma of the lower two-thirds of the rectum. Patients were seen every three months. Functional results were compared with those of 21 rectal cancer patients with straight coloanal anastomosis who underwent surgery in the same period and 20 normal patients.

RESULTS

There were two anastomotic leakages and one postoperative death. After one year, patients with pouch anastomosis had significantly less frequency of defecation and rectal urgency compared with those with straight anastomosis (P < 0.01); 48 percent of patients with straight anastomosis had more than five bowel movements per day, whereas all patients with pouch anastomosis had five or less bowel movements per day. Manometric studies showed maximum tolerable volume was significantly higher in patients with pouch anastomosis (81 vs. 152 ml; P < 0.01).

CONCLUSIONS

Stapled colonic J-pouch-anal anastomosis without a diverting colostomy is a reliable procedure that provides good, long-term functional results.

Monitoring lead pollution near a storage battery recycling plant in Taiwan, Republic of China

This study presents the distribution of blood lead levels and lead in various environmental samples (water, sediments, soils, and air) near the Shing-Yie storage battery recycling plant in Taiwan before (July 1990 to June 1991) and after (July 1992 to June 1993) amelioration. Before amelioration, the average blood lead levels in the neighborhood of the plant were in the range of 10.55 +/- 5.7 to 12.28 +/- 7.9 micrograms/dl. After amelioration, relatively lower average concentrations of blood lead (range 8.35 +/- 3.0 to 9.13 +/- 2.5 micrograms/dl) were generally found; however, these averages were still higher than that (7.79 +/- 3.5 micrograms/dl) from other lead-unpolluted areas of Taiwan. An exceedingly high geometric mean (GM) lead concentration (128 micrograms/L) was found in the downstream river water of the Tawulum River passing by the plant. The concentrations of lead (GM = 372 and 418 micrograms/g) in the downstream river sediments were higher than those (GM = 123 and 158 micrograms/g) in the upstream river sediments before and after amelioration, respectively. Furthermore, lead species in river sediments were analyzed by a sequential leaching technique. The sum of phases I, II, and III accounted for 83.7% of total lead at station R2 (nearest to the plant). Maximum lead concentration (GM = 2402 micrograms/g) in dust at the soil surface from station S1 (nearest to the plant) was much higher than those from the other stations by about 18 times before amelioration. However, the maximum value dropped to 1,155 micrograms/g after amelioration. On the whole, the geometric mean concentration of lead in dust at the soil surface nearest to the plant was > 1,000 micrograms/g and decreased to < 100 micrograms/g in the 15-30 cm depth soil about 2 km away from the plant. Before amelioration, the geometric mean lead concentration of 4.57 micrograms/m3 (range 0.102-37.6 micrograms/m3) in the air near the plant was higher than that at the background locations, the geometric mean value of which was 0.08 micrograms/m3.

The use of intranasal nitroglycerin to prevent pressor responses during intubation in general anesthesia--a comparison of various doses

BACKGROUND

Intranasal nitroglycerin (NTG) was first reported to successfully prevent an increase in arterial blood pressure following laryngoscopy and tracheal intubation by Hill et al. Various different effective dosages of NTG have been reported. Grover et al. indicated 0.75 mg of intranasal NTG to be the most suitable dose. However, no definite conclusion has yet been made. This study was designed to compare the efficacy of four different dosages of intranasal NTG (0.3, 0.5, 0.75, and 1.0 mg) in preventing pressor responses to laryngoscopy and tracheal intubation during the induction of general anesthesia.

METHODS

One hundred patients (ASA I or II) scheduled for elective surgery were included. These study subjects were divided into five groups and randomly assigned to four different dosages of intranasal NTG and a placebo. Each group consisted of 20 patients. The NTG solution was administered 1 min before the injection of thiopental. Systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) and heart rate (HR) were recorded before the induction of anesthesia (T1), before laryngoscopy (T2), and at 0, 3, and 5 min after tracheal intubation (T3, T4, and T5 respectively).

RESULTS

In patients who received a placebo (control group), there were significant increases in SAP, MAP, HR and rate-pressure-product (RPP) associated with tracheal intubation. Tachycardia was noted in all experimental groups. The increases in MAP associated with tracheal intubation were significantly less in patients who received NTG of 0.5 mg or more but not 0.3 mg. Although 0.5 mg of NTG did attenuate the increases in SAP after tracheal intubation, the increases in SAP of the other three experimental groups were no less than that of the control group. Rate-pressure-product (RPP) values of the experimental groups were noted to be equal to or higher than those of the control group during the period of study. Contrary to the results of the study conducted by Grover et al., 0.75 mg of NTG did not attenuate the pressor responses.

CONCLUSIONS

Intranasal NTG does not attenuate the pressor responses to laryngoscopy and tracheal intubation.

Psoas abscess due to mucinous cystadenocarcinoma of the appendix: a case report

Psoas muscle abscess is an uncommon and challenging entity. The present report describes a 64-year-old man presenting with right flank mass. Abdominal computerized tomography showed a right psoas abscess. Extraperitoneal drainage was performed, and pathology revealed metastatic mucinous adenocarcinoma. After further study, laparotomy and right hemicolectomy were performed under the impression of colon cancer. The final pathology showed mucinous cystadenocarcinoma of appendix. The literature about the etiology, diagnosis and treatment of psoas abscess are reviewed. Additionally, the treatment and prognosis for mucinous cystadenocarcinoma of the appendix are noted.

Subclinical neurotoxicity of mercury vapor revealed by a multimodality evoked potential study of chloralkali workers

Pattern visual, brainstem auditory, and somatosensory evoked potential (EP) studies were performed on 26 chloralkali workers. The intensity of mercury vapor exposure in these workers was estimated from the individual working history. Mercury levels in blood, urine, and hair were determined with atomic absorption spectrometry. The EP findings were compared with those from individually matched normal subjects. In brainstem auditory and somatosensory EP studies, prolonged neural conduction times in the central nervous system (CNS) were found in workers exposed to mercury vapor. In the pattern visual EP study, mercury workers had higher interpeak amplitudes. Findings of this study suggested that chronic exposure to mercury vapor would affect the CNS functions. A multimodality EP study is a useful adjunct in evaluation of chronic mercury neurotoxicity, especially in an epidemiological study.

[Continuing hospice care of cancer--a three-year experience]

The hospice at Mackay Memorial Hospital was established in February 1990. A group of team workers including physicians, nurses, social workers and the clergy were involved in this holistic care program for terminal cancer patients. Four hundred and seventy-nine patients were eligible for the program up to February 1993. Regarding duration of stay, 62.5% of patients resided for 14 days. Those surviving under 90 days constituted 75.5% of patients. Fifty-one point eight percent of patients died in the hospice and 18.2% died at home soon after being discharged from the hospice. Pain is the most common symptom among the patients. Treatment strategies vary according to the three-step-ladder protocol designed by WHO. Total pain relief was achieved in 80% of patients. Opportune private talking and family conferences formed the basis of the "peer model". Through this model, treatment decisions including physical, psychosocial and spiritual issues were made. Before the peer model, only 36 (10.3%) patients agreed with the idea of hospice care, while 257 (73.6%) patients agreed after the model was established. Awareness of dying was evident in 412 (86%) patients. Two hundred and eighty (68%) patients became aware of the prospect of death through guessing, while the other 132 (32%) patients were informed by medical staff. Problems encountered by the team workers included 1) needs in education and training, 2) psychological pressure, 3) management of loss and grief, 4) needs in supportive system and 5) troubles caused by families' lying to patients. The team workers were satisfied with the quality of care in 38.4% of patients and fairly satisfied with 30.7% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Management of anorexic patients in radiotherapy: a prospective randomized comparison of megestrol and prednisolone

Megestrol acetate and corticosteroid have been demonstrated to be effective in the treatment of anorexia in patients with advanced cancer. The purpose of this preliminary study is to evaluate the role of megestrol acetate and prednisolone in the treatment of anorexia induced during whole pelvis external irradiation. Fifty-two patients were randomized in this prospective study to either receive megestrol acetate (40 mg orally four times a day), prednisolone (10 mg orally three times a day), or placebo (1 tablet orally three times a day) for 21 consecutive days. Body weight, appetite, performance status, sense of well-being, and complications were assessed every 3 days. Both the megestrol acetate group and the prednisolone group showed improvement in body weight gain, appetite, performance status, and sense of well-being. Appetite improvement was statistically significant in the megestrol acetate group (P = 0.024) when compared with the placebo group. There were no complications during the 21-day trial.

Radiotherapy following simple hysterectomy in patients with invasive carcinoma of the uterine cervix

From January 1980 to December 1988, a total of 73 cases of invasive cervical cancer after simple hysterectomy were treated with radiotherapy. Seven patients were excluded due to incomplete treatment or loss of follow-up. Among the 66 patients, 52 had squamous cell carcinoma and 14 had adenocarcinoma or adenosquamous cell carcinoma. The patients were grouped as follows: group A, patients without gross residual tumor (n = 32); group B, patients with gross residual tumor (n = 23); and group C, patients with gross recurrent tumor (n = 11). All patients in groups A and B received radiotherapy immediately (within 4 months) following their simple hysterectomy. Patients in group C were treated six months to five years later. Different methods of radiotherapy were delivered during the two consecutive time periods. Before 1985, patients (n = 30) were irradiated with a dose of 45-50 Gy in the midpelvic plane, followed by a transvaginal boost of 30 Gy. After 1985, patients (n = 36) were treated with the same midpelvic dose, and boosted with 30 Gy by high-dose-rate brachytherapy. The overall five-year survival rate was 67%. The five-year survival rates were 81% in group A, 56% in group B, and 45% in group C. A low complication rate (10%) was obtained in our series.(ABSTRACT TRUNCATED AT 250 WORDS)

Radiotherapy for locally recurrent breast cancer

A total of 43 breast cancer patients were treated at the Department of Radiation Oncology, Mackay Memorial Hospital from January 1978 to December 1987 for postoperative local-regional recurrence. Twenty-six patients developed local recurrence within 12 months after surgery and 17 patients developed local recurrence after 12 months. The mean age for this group of patients was 52 years (range: 27-82). There were 26 postmenopausal and 17 premenopausal patients. Twenty-four patients had received chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) regimen. Four patients were excluded from this study due to incompletion of radiotherapy. Sites of local recurrence in the remaining 39 patients included: chest wall, single (8) and multiple (4); axilla (7); supraclavicular area (5); chest wall with regional node (11); and multiple regional nodes (4). All were free of distant metastasis at the initiation of radiotherapy. A mean tumor dose of 5000 cGy in 28 fractions was given over a 6-week period to the chest wall and draining lymphatics, using an AECL Theratron 80 or a CGR Alcyon MEV Cobalt-60 unit. The overall local control rate was 72%, and the 5-year local control rate was 59%. Nine patients experienced a second local recurrence, with a median interval of 8 months after radiotherapy. Four of them (4/9) also showed evidence of systemic disease at the same time. Distant metastasis, the major cause of mortality, appeared in 49% of the patients with a median interval of 22.8 months after radiotherapy. The three leading sites of distant metastasis were the bones (42%), lungs (37%) and liver (16%).(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention of hypothermia during abdominal surgery: comparison of thermal tube and blanket

Twenty patients who received elective abdominal surgery for more than two hours were randomly assigned into two groups. Group 1 was warmed by using "EXACON" thermal therapy system model TT8200. Group 2 was warmed by using a thermal blanket of aquamatic K-thermia (electronic control), model PK-600 of American Hamilton medical systems. Other variables were kept constant, and the theater temperature was maintained at 24 degrees C. Core temperature was recorded every five minutes in a two hour period. There were statistically significant differences between these two groups intra-operatively. Decrease of temperature between these two groups had significant changes from 30 minutes to 2 hours (p less than 0.05). The warming effect of esophageal thermal tube was well controlled by directly warming the central compartment. However, the effect of blanket was unpredictable due to wet dressing and superficial warming of surgical fields. There were no side effects during the study.

The optimal dose of atropine via the endotracheal route

Fifty ASA class I or II patients, undergoing general or gynecological surgery under general anesthesia with endotracheal intubation, were randomly divided into five groups. Group I received 10 ug/kg atropine intravenously, group II to V received 10 ug/kg, 20 ug/kg, 30 ug/kg, 40 ug/kg, respectively via endotracheal route through an epidural catheter. All were given five manual deep breaths after the injection of atropine. The maximum increase in heart rate (MIHR) and the time to maximum heart rate (TMHR) were evaluated. There was no marked MIHR in group II. Group III had a MIHR similar to that of group I (17.5/min vs 20/min, p greater than 0.05), but had a longer TMHR than group I (120 sec vs 82.5 sec, p less than 0.005). Groups IV and V had greater MIHR than group I (28.7 and 29.5 vs 20/min, p less than 0.005), and a TMHR similar to that of group I (85 and 90.2 vs 82.5 sec, p greater than 0.05). For emergency procedures, if atropine must be given without an intravenous catheter, 30 ug/kg or more given endotracheally can achieve an effect comparable to that of 10 ug/kg given intravenously.