[Multimodal imaging analysis of the cyst like lesion of condyle in temporomandibular joint]

Objective: To investigate the imaging features of condylar cystic degeneration of temporomandibular joint (TMJ) by cone-beam CT (CBCT), spiral CT, MRI and radionuclide bone imaging. Methods: From January 2018 to December 2020, thirty-two patients with cyst-like lesions of condylein temporomandibular joint were examined by CBCT, spiral CT, MRI and radionuclide bone imaging at the Department of Oral and Maxillofacial Surgery in General Hospital of Chinese PLA. There were 12 males and 20 females involved, aged from 16 to 65 years with an average age of (33.9±12.5) years. The characteristics of CBCT, spiral CT, MRI and radionuclide bone imaging were analyzed. Condylar cyst like lesions were classified as type A and type B based on the presence or absence of surface bone defects. Condylar cyst like lesions were classified as type Ⅰ(yes) and type Ⅱ(no) according to the accompanying bone marrow edema-like lesions of the condyles. The incidence of condylar bone marrow edema, disc displacement and abnormal bone metabolism were analyzed. Results: A total of 64 joint images of 32 patients were included, including 34 sides with TMJ cyst-like lesion and 6 sides with multiple cyst-like lesions,the total cyst-like lesions were 42. The largest diameter of cyst-like lesion ranged from 1.0 to 12.4 mm, with an average length of (3.7± 1.8) mm. There were 24 cases of type A TMJ cyst like lesion and 10 cases of type B cyst-like lesion. The detection rate of CBCT was 95.2% (40/42) and that of spiral CT was 100% (42/42), there was no significant difference (Calibration Chi-square=0.51, P=0.474). The detection rate of nuclear magnetic resonance was 80.1% (34/42), and the detection rate of cyst-like lesions less than 2 mm was 3/11. In the cyst like lesion side, there were 9 sides with anterior disc displacement with reduction, 20 sides with anterior disc displacement without reduction. In the non-cyst like lesion side, 10 sides with anterior disc displacement with reduction and 6 sides with anterior disc displacement without reduction. There was a significant difference in the displacement of the disc between cyst-like and non-cystic lesion side (χ²=7.80, P=0.005). MRI showed that 6 cases of cystic side[17.6% (6/34)] had bone marrow edema-like lesions (all type A), 1 case of non-cyst like lesions side [3.3% (1/30)] had bone marrow edema-like lesion, there was no significant difference between cystic and non-cystic lesions (Calibration Chi-square=2.04, P=0.153). There was a significant difference between type A and B cystic lesions (Fisher exact probability method, P=0.024). Radionuclide bone imaging showed abnormal bone metabolism in 26 patients in the cyst-like lesion side and 5 patients in the non-cyst like lesion side (χ²=22.82, P<0.001). Conclusions Multi-slice Spiral CT could detect the cyst-like lesion of TMJ condyle in the early stage, which is different from the large joint. And the formation mechanism may vary from the different classifications.

[Multimodal imaging analysis of the cyst like lesion of condyle in temporomandibular joint]

Objective: To investigate the imaging features of condylar cystic degeneration of temporomandibular joint (TMJ) by cone-beam CT (CBCT), spiral CT, MRI and radionuclide bone imaging. Methods: From January 2018 to December 2020, thirty-two patients with cyst-like lesions of condylein temporomandibular joint were examined by CBCT, spiral CT, MRI and radionuclide bone imaging at the Department of Oral and Maxillofacial Surgery in General Hospital of Chinese PLA. There were 12 males and 20 females involved, aged from 16 to 65 years with an average age of (33.9±12.5) years. The characteristics of CBCT, spiral CT, MRI and radionuclide bone imaging were analyzed. Condylar cyst like lesions were classified as type A and type B based on the presence or absence of surface bone defects. Condylar cyst like lesions were classified as type Ⅰ(yes) and type Ⅱ(no) according to the accompanying bone marrow edema-like lesions of the condyles. The incidence of condylar bone marrow edema, disc displacement and abnormal bone metabolism were analyzed. Results: A total of 64 joint images of 32 patients were included, including 34 sides with TMJ cyst-like lesion and 6 sides with multiple cyst-like lesions,the total cyst-like lesions were 42. The largest diameter of cyst-like lesion ranged from 1.0 to 12.4 mm, with an average length of (3.7±1.8) mm. There were 24 cases of type A TMJ cyst like lesion and 10 cases of type B cyst-like lesion. The detection rate of CBCT was 95.2% (40/42) and that of spiral CT was 100% (42/42), there was no significant difference (Calibration Chi-square=0.51, P=0.474). The detection rate of nuclear magnetic resonance was 80.1% (34/42), and the detection rate of cyst-like lesions less than 2 mm was 3/11. In the cyst like lesion side, there were 9 sides with anterior disc displacement with reduction, 20 sides with anterior disc displacement without reduction. In the non-cyst like lesion side, 10 sides with anterior disc displacement with reduction and 6 sides with anterior disc displacement without reduction. There was a significant difference in the displacement of the disc between cyst-like and non-cystic lesion side (χ²=7.80, P=0.005). MRI showed that 6 cases of cystic side[17.6% (6/34)] had bone marrow edema-like lesions (all type A), 1 case of non-cyst like lesions side [3.3% (1/30)]had bone marrow edema-like lesion, there was no significant difference between cystic and non-cystic lesions (Calibration Chi-square=2.04, P=0.153). There was a significant difference between type A and B cystic lesions (Fisher exact probability method, P= 0.024). Radionuclide bone imaging showed abnormal bone metabolism in 26 patients in the cyst-like lesion side and 5 patients in the non-cyst like lesion side (χ²=22.82, P<0.001). Conclusions Multi-slice Spiral CT could detect the cyst-like lesion of TMJ condyle in the early stage, which is different from the large joint. And the formation mechanism may vary from the different classifications.

[Anatomical study of rat trigeminal motor nucleus-lateral pterygoid muscle projection pathway]

Objective: To determine the opening and closing action of the external muscle, the projection pathway of the axon terminal of trigeminal motor nucleus (Vmo) neuron to the lateral pterygoid muscle was revealed. Methods: In this study, 10 SD rats of 8 weeks old were included. The left lateral pterygoid muscle of SD rats was surgically exposed, and the wound was closed after intramuscular injection of hydroxystilbamidine/fluorogold (FG) 3-5 μl. Seven days after the operation, the experimental animals were perfused, samples collected and sectioned for immunofluorescence staining. After FG injection into the lateral pterygoid muscle, the FG reversed in the Vmo neurons. Results: In the Vmo neurons on the FG injection side (left side), a large number of FG reversed neurons were found in the corpus luteum and dendrites. These neurons were not only distributed in the dorsolateral part of the trigeminal motor nucleus that innervated the closed muscle, but also in the ventral medial portion of the trigeminal nucleus of the open muscle. Conclusions: The neuronal conduction pathway between the Vmo and the lateral pterygoid muscle innervates the lateral pterygoid muscle. The neurons are distributed both in the dorsolateral and in the nucleus of the ventral ventricle. It is concluded that the lateral pterygoid muscle involve in the jaw closing and opening movement.

NUTRITIONAL RISK STATUS, DIETARY INTAKE AND COGNITIVE PERFORMANCE IN OLDER ADULTS WITH MOTORIC COGNITIVE RISK SYNDROME

Background

Modifiable lifestyle factors such as diet are associated with cognitive decline and dementia. Greater understanding of the nutritional intake of older adults who are at increased risk for cognitive decline may allow for the development of more effective dietary interventions to prevent or delay the onset of dementia.

Objectives

The purpose of this study was to characterize the nutritional status, diet quality and individual nutritional components of older adults with motoric cognitive risk syndrome (MCR). MCR is a pre-dementia syndrome classified by slow gait speed and subjective memory impairments.

Design

Cross-sectional analysis.

Setting

A community-based senior center located in an urban setting.

Participants

Twenty-five community-dwelling older adults with MCR aged 60-89 yrs.

Measurements

Nutritional risk status was determined using the Nestle Mini Nutritional Assessment (MNA). A food frequency questionnaire was used to quantify: overall dietary quality using the Healthy Eating Index (HEI); adherence to the Mediterranean-DASH for Neurodegenerative Delay (MIND) dietary pattern; and intake of individual nutritional components shown to be protective or harmful for cognitive function in older adults. Participants completed a computerized cognitive testing battery to assess cognitive abilities.

Results

More than one third (36%) of participants were at increased risk for malnutrition. Participants at lower risk for malnutrition had better working memory (r = 0.40, p = 0.04), executive functioning (r = 0.44, p = 0.03), and overall cognition (r = 0.44, p = 0.03). While participants generally consumed a reasonable quality diet (HEI = 65.15), 48% of participants had poor adherence to a neuroprotective MIND dietary pattern. Higher intake of B-complex vitamins was associated with better task switching (r = 0.40, p ≤ 0.05) and faster processing speeds (r = 0.39, p ≤ 0.05). Higher vitamin C intake was associated with better executive functioning (r = 0.40, p ≤ 0.05).

Conclusions

Our findings suggest that a significant proportion of older adults with MCR may be at increased risk for malnutrition. While the diet quality of older adults with MCR appeared to need improvement, future studies should investigate the effects of more specific nutritional interventions, including the MIND diet, on cognition in at-risk older adults.

[Proton nuclear magnetic resonance spectroscopy recognition of metabolic patterns in fecal extracts for early diagnosis of colorectal cancer]

Objective: To characterize the metabolic " fingerprint" of fecal extracts for diagnosis of early-stage colorectal cancer(CRC)using proton nuclear magnetic resonance spectroscopy(¹H-NMR)-based metabolomics coupled with pattern recognition. Methods: From January 2014 to December 2014, we collected fecal samples at the Second Affiliated Hospital of Shantou University Medical College, from 25 patients with colorectal adenomas(CR-Ad), 20 with stage Ⅰ/Ⅱ CRC, and 32 healthy controls(HCs). The patients were diagnosed by histopathology. No subjects had any complicating diseases. HCs showed no abnormalities from blood tests, endoscopic examination, diagnostic imaging, and/or medical interviews. We excluded participants who used antibiotics, NSAIDS, statins, or probiotics within two months of study participation, and any patients who underwent chemotherapy or radiation treatments prior to surgery. We used orthogonal partial least-squares-discriminant analysis(OPLS-DA)for pattern recognition(dimension reduction)on ¹H-NMR processed data(¹H frequency of 400.13 MHz), to find metabolic differences among CR-Ad, carcinoma and HC fecal samples; and receiver operating characteristic(ROC)analysis to determine the diagnostic value of the fecal metabolic biomarkers. Results: Fecal samples were collected from 20 patients with Stage Ⅰ/Ⅱ CRC(11 M, 9 F, median age(52±13)years), 25 with CR-Ad(14 M, 11 F, median age(53 ± 11)years)and 32 HCs(15 M, 17 F, median age(53 ± 14)years). OPLS-DA clearly distinguished CR-Ad and stage Ⅰ/Ⅱ CRC from HC samples, based on their metabolomic profiles. Relative signal intensities in HCs were significantly lower than in the cancer patients for butyrate(HC: 23.0±6.0; CR-Ad: 18.0±5.0; CRC: 14.0±6.0; Z=-2.07, P=0.008), acetate(HC: 45.0±11.0; CR-Ad: 31.0±11.0; CRC: 24.0±8.0; Z=- 2.32, P=0.011), propionate(HC: 26.0 ± 7.0; CR-Ad: 22.0 ± 6.0; CRC: 19.0 ± 5.0; Z=- 2.43, P=0.032), glucose(HC: 37.0±7.0; CR-Ad: 31.0±7.0; CRC: 26.0±8.0; Z=-2.07, P=0.044)and glutamine(HC: 4.5±2.0; CR-Ad: 4.9 ± 1.0; CRC: 5.4 ± 1.0; Z=2.21, P=0.044). However, relative signal intensities in HCs were significantly higher than in patients for lactate(HC: 4.8±1.0; CR-Ad: 6.9±2.0; CRC: 4.8± 1.0; Z=2.02, P= 0.038), glutamate(HC: 3.2 ± 2.0; CR-Ad: 4.9 ± 1.0; CRC: 3.2 ± 2.0; Z=2.21, P=0.044)and succinate(HC: 12.0±2.0; CR-Ad: 15.0±3.0; CRC: 12.0± 2.0; Z=2.25, P=0.011). Among the potential biomarkers, acetate at 1.92 ppm, and succinate at 2.41 ppm displayed relatively high area under ROC, with sensitivity and specificity both >90%, to distinguish early-stage CRC patients from HCs. Conclusion: Fecal metabolic profiles distinguish of HCs from patients with CRC patients, even in the early stages(stage Ⅰ/Ⅱ), highlighting the potential of NMR-based fecal metabolomic fingerprinting as tools for early CRC diagnosis.

The Effect of Chronic Kidney Disease on a Physical Activity Intervention: Impact on Physical Function, Adherence, and Safety

Background

Because chronic kidney disease (CKD) is associated with muscle wasting, older adults with CKD are likely to have physical function deficits. Physical activity can improve these deficits, but whether CKD attenuates the benefits is unknown. Our objective was to determine if CKD modified the effect of a physical activity intervention in older adults.

Methods

This is an exploratory analysis of the LIFE-P study, which compared a 12-month physical activity program (PA) to a successful aging education program (SA) in older adults. CKD was defined as a baseline eGFR < 60 mL/min/1.73 m². We examined the Short Physical Performance Battery (SPPB) at baseline, 6 and 12 months. Secondary outcomes included serious adverse events (SAE) and adherence to intervention frequency. Linear mixed models were adjusted for age, sex, diabetes, hypertension, CKD, intervention, site, visit, baseline SPPB, and interactions of intervention and visit and of intervention, visit, and baseline CKD.

Results

The sample included 368 participants. CKD was present in 105 (28.5%) participants with a mean eGFR of 49.2 ± 8.1 mL/min/1.73 m². Mean SPPB was 7.38 ± 1.41 in CKD participants; 7.59 ± 1.44 in those without CKD (p = 0.20). For CKD participants in PA, 12-month SPPBs increased to 8.90 (95% CI 8.32, 9.47), while PA participants without CKD increased to 8.40 (95% CI 8.01, 8.79, p = 0.43). For CKD participants in SA, 12-month SPPBs increased to 7.67 (95% CI 7.07, 8.27), while participants without CKD increased to 8.12 (95% CI 7.72, 8.52, p = 0.86). Interaction between CKD and intervention was non-significant (p = 0.88). Number and type of SAEs were not different between CKD and non-CKD participants (all p > 0.05). In PA, adherence for CKD participants was 65.5 ± 25.4%, while for those without CKD was 74.0 ± 22.2% (p = 0.12).

Conclusion

Despite lower adherence, older adults with CKD likely derive clinically meaningful benefits from physical activity with no apparent impact on safety, compared to those without CKD.

Effect of Structured Physical Activity and Nutritional Supplementation on Physical Function in Mobility-Limited Older Adults: Results from the VIVE2 Randomized Trial

OBJECTIVES

The interactions between nutritional supplementation and physical activity on changes in physical function among older adults remain unclear. The primary objective of this study was to examine the impact of nutritional supplementation plus structured physical activity on 400M walk capacity in mobility-limited older adults across two sites (Boston, USA and Stockholm, Sweden).

DESIGN

All subjects participated in a physical activity program (3x/week for 24 weeks), involving walking, strength, balance, and flexibility exercises. Subjects were randomized to a daily nutritional supplement (150kcal, 20g whey protein, 800 IU vitamin D) or placebo (30kcal, non-nutritive).

SETTING

Participants were recruited from urban communities at 2 field centers in Boston MA USA and Stockholm SWE.

PARTICIPANTS

Mobility-limited (Short Physical Performance Battery (SPPB) ≤9) and vitamin D insufficient (serum 25(OH) D 9 - 24 ng/ml) older adults were recruited for this study.

MEASUREMENTS

Primary outcome was gait speed assessed by the 400M walk.

RESULTS

149 subjects were randomized into the study (mean age=77.5±5.4; female=46.3%; mean SPPB= 7.9±1.2; mean 25(OH)D=18.7±6.4 ng/ml). Adherence across supplement and placebo groups was similar (86% and 88%, respectively), and was also similar across groups for the physical activity intervention (75% and 72%, respectively). Both groups demonstrated an improvement in gait speed with no significant difference between those who received the nutritional supplement compared to the placebo (0.071 and 0.108 m/s, respectively (p=0.06)). Similar effects in physical function were observed using the SPPB. Serum 25(OH)D increased in supplemented group compared to placebo 7.4 ng/ml versus 1.3 ng/ml respectively.

CONCLUSION

Results suggest improved gait speed following physical activity program with no further improvement with added nutritional supplementation.

Effect of Load Deflection on Corrosion Behavior of NiTi Wire

For dental orthodontic applications, NiTi wires are used under bending conditions in the oral environment for a long period. The purpose of this study was to investigate the effect of bending stress on the corrosion of NiTi wires using potentiodynamic and potentiostatic tests in artificial saliva. The results indicated that bending stress induces a higher corrosion rate of NiTi wires in passive regions. It is suggested that the passive oxide film of specimens would be damaged under bending conditions. Auger electron spectroscopic analysis showed a lower thickness of passive films on stressed NiTi wires compared with unstressed specimens in the passive region. By scanning electron microscopy, localized corrosion was observed on stressed Sentalloy specimens after a potentiodynamic test at pH 2. In conclusion, this study indicated that bending stress changed the corrosion properties and surface characteristics of NiTi wires in a simulated intra-oral environment.

Nephrolithiasis among male patients with newly diagnosed gout

INTRODUCTION

An elevated serum urate level is recognised as a cause of gouty arthritis and uric acid stone. The level of serum uric acid that accelerates kidney stone formation, however, has not yet been clarified. This study aimed to find out if a high serum urate level is associated with nephrolithiasis.

METHODS

Patients were recruited from the rheumatology clinic of Taipei City Hospital (Renai and Zhongxing branches) in Taiwan from March 2015 to February 2016. A total of 120 Chinese male patients with newly diagnosed gout and serum urate concentration of >7 mg/dL and no history of kidney stones were divided into two groups according to their serum urate level: <10 mg/dL (group 1, n=80) and ≥10 mg/dL (group 2, n=40). The mean body mass index, blood urea nitrogen level, creatinine level, urinary pH, and kidney ultrasonography were compared between the two groups.

RESULTS

There were no significant differences in blood urea nitrogen or creatinine level between the two groups. The urine pH in both groups was similar and not statistically significant. Kidney stone formation was detected via ultrasonography in 6.3% (5/80) and 82.5% (33/40) of patients in groups 1 and 2, respectively (P<0.05).

CONCLUSION

A serum urate level of ≥10 mg/dL may precipitate nephrolithiasis. Further studies are warranted to substantiate the relationship between serum urate level and kidney stone formation.

No increased risk of coronary heart disease for patients receiving androgen deprivation therapy for prostate cancer in Chinese/Taiwanese men

The relationship between androgen deprivation therapy (ADT) and coronary heart disease (CHD) remains controversial. Furthermore, the majority of such studies focused on Caucasian populations, and there is still a paucity of studies among Asian populations. This population-based study aimed to investigate the relationship between ADT and CHD in an ethnic Chinese (i.e., Taiwanese) population. We used data sourced from the Taiwan 'Longitudinal Health Insurance Database'. This study included 1278 patients with prostate cancer in the study group and 1278 subjects without prostate cancer in the comparison group. Each patient was individually tracked for a 3-year period to identify those who had subsequently received a diagnosis of CHD. The results showed that the incidence rate of CHD during the 3-year follow-up period was 4.69 (95% CI: 2.99-5.48) per 100 person-years and 2.67 (95% CI: 2.15-3.27) per 100 person-years for the study and comparison cohort, respectively. The Cox proportional hazard regression showed that the hazard ratio for CHD during the 3-year follow-up period for prostate cancer patients was 1.65 (95% confidence interval (CI) = 1.25-2.16) compared with comparison subjects after adjusting for patients' geographic location, monthly income, urbanization level, hypertension, diabetes, hyperlipidemia, and stroke. However, we failed to find a significant difference in the adjusted hazard of CHD during the 3-year follow-up period between prostate cancer patients who did and those who did not receive ADT (hazard ratio = 1.12, 95% CI = 0.79-1.59). We concluded that prostate cancer but not ADT was significantly associated with CHD. In addition, a common cause of prostate cancer and coronary heart disease could exist.

The impact of sarcopenia on a physical activity intervention: the Lifestyle Interventions and Independence for Elders Pilot Study (LIFE-P)

OBJECTIVE

To determine if sarcopenia modulates the response to a physical activity intervention in functionally limited older adults.

DESIGN

Secondary analysis of a randomized controlled trial.

SETTING

Three academic centers.

PARTICIPANTS

Elders aged 70 to 89 years at risk for mobility disability who underwent dual-energy x-ray absorptiometry (DXA) for body composition at enrollment and follow-up at twelve months (N = 177).

INTERVENTION

Subjects participated in a physical activity program (PA) featuring aerobic, strength, balance, and flexibility training, or a successful aging (SA) educational program about healthy aging.

MEASUREMENTS

Sarcopenia as determined by measuring appendicular lean mass and adjusting for height and total body fat mass (residuals method), Short Physical Performance Battery score (SPPB), and gait speed determined on 400 meter course.

RESULTS

At twelve months, sarcopenic and non-sarcopenic subjects in PA tended to have higher mean SPPB scores (8.7±0.5 and 8.7±0.2 points) compared to sarcopenic and non-sarcopenic subjects in SA (8.3±0.5 and 8.4±0.2 points, p = 0.24 and 0.10), although the differences were not statistically significant. At twelve months, faster mean gait speeds were observed in PA: 0.93±0.4 and 0.95±0.03 meters/second in sarcopenic and non-sarcopenic PA subjects, and 0.89±0.4 and 0.91±0.03 meters/second in sarcopenic and non-sarcopenic SA subjects (p = 0.98 and 0.26), although not statistically significant. There was no difference between the sarcopenic and non-sarcopenic groups in intervention adherence or number of adverse events.

CONCLUSION

These data suggest that older adults with sarcopenia, who represent a vulnerable segment of the elder population, are capable of improvements in physical performance after a physical activity intervention.

Surface functionalization of Cu-Ni alloys via grafting of a bactericidal polymer for inhibiting biocorrosion by Desulfovibrio desulfuricans in anaerobic seawater

A novel surface modification technique was developed to provide a copper nickel alloy (M) surface with bactericidal and anticorrosion properties for inhibiting biocorrosion. 4-(chloromethyl)-phenyl tricholorosilane (CTS) was first coupled to the hydroxylated alloy surface to form a compact silane layer, as well as to confer the surface with chloromethyl functional groups. The latter allowed the coupling of 4-vinylpyridine (4VP) to generate the M-CTS-4VP surface with biocidal functionality. Subsequent surface graft polymerization of 4VP, in the presence of benzoyl peroxide (BPO) initiator, from the M-CTS-4VP surface produced the poly(4-vinylpyridine) (P(4VP)) grafted surface, or the M-CTS-P(4VP) surface. The pyridine nitrogen moieties on the M-CTS-P(4VP) surface were quaternized with hexylbromide to produce a high concentration of quaternary ammonium groups. Each surface functionalization step was ascertained by X-ray photoelectron spectroscopy (XPS) and static water contact angle measurements. The alloy with surface-quaternized pyridinium cation groups (N+) exhibited good bactericidal efficiency in a Desulfovibrio desulfuricans-inoculated seawater-based modified Barr's medium, as indicated by viable cell counts and fluorescence microscopy (FM) images of the surface. The anticorrosion capability of the organic layers was verified by the polarization curve and electrochemical impedance spectroscopy (EIS) measurements. In comparison, the pristine (surface hydroxylated) Cu-Ni alloy was found to be readily susceptible to biocorrosion under the same environment.

Bilateral Video-Assisted Thoracoscopic Thymectomy vs. Extended Transsternal Thymectomy in Myasthenia Gravis: A Prospective Study

The optimal approach to thymectomy remains controversial. This study is designed to prospectively compare the results between bilateral video-assisted thoracoscopic thymectomy (BVTx) and extended transsternal thymectomy (ETTx) in patients with myasthenia gravis (MG) without thymoma. Fifteen patients who had undergone BVTx and 16 patients who had undergone ETTx were compared for age, gender, severity of disease, preoperative duration of disease, operative time, intraoperative blood loss, postoperative complications, hospital stay, duration of chest tube drainage, thymic histopathology, pain perception by visual analog scale (VAS), remission and improvement rate, period of follow-up, and activities of daily living (ADL). Fisher's exact test, t test and paired t test were used for statistical analysis. BVTx had longer operative time and less intraoperative blood loss than that of the ETTx. Their remission rates and their degree of postoperative ADL improvement were not significantly different. However, the lowering of VAS was significantly greater in the sternotomy group at 3 months. All other parameters were not significantly different. No mortality was noted in the series. We consider BVTx as an effective alternative procedure to the transsternal approach for patients with nonthymomatous MG. As more and more people care about cosmetics, BVTx could become the future trend.

[The entrapped efficiency of BSA liposome]

BSA liposomes were prepared with approximately 100 nm mean particle size under rather gentle experiment conditions, and two-colorimetric coomassie brilliant blue protein was employed to measure the free drug in the entrapped efficiency (EE%) determination of BSA liposomes. Gel filtration was used to measure the EE%, and several Sephadex gels were examined by the separation of liposomes and free drug. To determine the free drug, three methods were compared on two-colorimetric UV spectrophotography, Bradford and two-colorimetric coomassie brilliant blue, separately. Two-colorimetric coomassie brilliant blue process increased the accuracy and improved the sensitivity of the assay about 20-fold comparing with the Bradford method. Two-colorimetric coomassie brilliant blue assay appeared to be more sensitive and showed broader dynamic range to measure the free BSA in the EE% determination of BSA liposome.

Apolipoprotein E in Taiwan Chinese patients with dementia

To clarify whether Alzheimer's disease (AD) and vascular dementia (VaD) share the same risk factors in Taiwan Chinese patients. Using the criteria of the NINCDS- ADRDA and NINDS-AIREN, 154 AD patients, 30 VaD patients, and 112 controls were enrolled. Their apolipoprotein E (ApoE) genes, extracted from peripheral blood leukocytes, were analyzed. The epsilon4 allele frequency was significantly higher in AD patients than in the control group. The odds ratio of carrying at least one copy of the epsilon4 allele in AD patients is 2.7 compared with control subjects. There was no significant difference between the VaD patients and the control subjects in their ApoE epsilon4 or epsilon2 allele frequency. The present study demonstrates a strong association between the ApoE epsilon4 allele and AD, but not between the ApoE epsilon4 allele and VaD. This suggests that AD and VaD do not share the same pathogenesis and deserve further investigation.

Glucose/lipid mixed substrates as a means of controlling the properties of medium chain length poly(hydroxyalkanoates)

Glucose-triacylglycerol (TAG) mixed substrates were used to modulate the physical and mechanical properties of medium-chain-length poly(hydroxyalkanoates) (mcl-PHAs). Pseudomonas resinovorans NRRL B-2649 grew and produced mcl-PHAs on glucose and TAGs (coconut oil, C; soybean oil, S) after 24 h in a shake flask culture. However, with the exception of coconut oil, maximum cell productivity was not reached in any of the cultures until 72 h post-inoculation. Here, 50:50 mixtures of glucose and coconut oil (glc/C) or glucose and soybean oil (glc/S) resulted in intermediate cell productivities with a maximum of 57% and 48% of the CDW at 72 h, respectively. In addition, mixed substrates resulted in mcl-PHAs with compositions that varied slightly over time. PHA-glc/C and PHA-glc/S were composed of 7 mol % and 8 mol % 3-hydroxydodecenoic acid (C(12:1)), respectively at 72 h. These concentrations were intermediate to the C(12:1) concentration of PHA-glc and respective PHA-TAG. Also, significant amounts of 3-hydroxytetradecanoic acid (C(14:0)), 3-hydroxytetradecenoic acid (C(14:1)), and 3-hydroxytetradecadienoic acid (C(14:2)) were present in PHA-glc/C and PHA-glc/S, which were derived from the respective TAG, as glucose resulted in almost no C(14:)(X) monomers. The molar masses of each of the polymers remained relatively constant between 24 and 96 h. At 72 h, the number-average molar masses (M(n)) of PHA-glc/C and PHA-glc/S were 178,000 and 163,000 g/mol, respectively, which were also intermediate to the M(n) of PHA-glc (225,000 g/mol) and the respective PHA-TAG (PHA-C = 153,000 g/mol; PHA-S = 75,000 g/mol). These physical differences caused variations in the mechanical properties of mcl-PHA films, thus providing a new and effective method of modifying their properties.

Neuropsychiatric symptoms of Alzheimer's disease differ in Chinese and American patients

BACKGROUND

The prevalence of Alzheimer's disease is similar across ethnic groups. To our knowledge, no comparison of behavioral symptoms has been addressed.

OBJECTIVE

This cross-sectional, retrospective, descriptive study compares neuropsychiatric symptoms of Chinese subjects with Alzheimer's disease (AD) at tertiary care centers in Taiwan and Hong Kong against Caucasian subjects in Los Angeles, California. We compared the frequency and severity of symptoms and caregiver responses to neuropsychiatric symptoms of AD using the Neuropsychiatric Inventory (NPI). We hypothesized that Chinese patients do not seek care unless they have high severity of neuropsychiatric symptoms and that Caucasian Americans do not wait for behavioral disturbances to develop before coming to medical attention.

RESULTS

The Caucasian sample had the highest mean educational level and mildest Clinical Dementia Rating (CDR) scale distributions of all four groups. Older age and lower educational levels contributed to higher CDR scale scores, which in turn correlated with higher total NPI scores. Only one of the Chinese samples had a higher frequency of severe neuropsychiatric symptoms than the Caucasian sample. Chinese caregivers reported anxiety and delusions more frequently (58.1%) than Caucasians (37.3% and 39.6%; chi(2), p < 0.01 and p < 0.05, respectively). Caucasians reported appetite changes (47.3%) and apathy (59.2%) more frequently than the Chinese samples (chi(2), p < 0.05 and p < 0.01, respectively). Caregivers at all four centers were distressed by behaviors qualified as severe.

CONCLUSION

We found support for our hypothesis, in that Chinese subjects presented during a more severe stage of dementia than American subjects, but the delay in seeking care could not be correlated with significant differences in neuropsychiatric profiles of the demented subjects. Other barriers to dementia care warrant investigation.

Rehabilitation fees, length of stay and efficiency for hospitalized stroke patients: a preliminary study based on function-related groups

The purpose of this study was to examine the relationships between severity of disability and factors such as rehabilitation fees, length of stay and efficiency for hospitalized stroke patients. One hundred and seven first-time stroke patients were studied consecutively for this study. They were recruited from a rehabilitation ward in a university medical center during 1997. Functional ability was evaluated using the Functional Independence Measure (FIM) instrument on admission and discharge. Stroke patients who presented with similar degrees of disability were put together using the admission FIM score (FIM Function-Related Groups, FIM-FRGs) for further analysis. Twenty-eight (26.2%) patients examined were categorized as severely disabled (scored 18-36), 48 (44.8%) moderately disabled (scored 37-72) and 31 (29.0%) mildly disabled (scored 73-126). The average expense on rehabilitation fees, for the average rehabilitation length of stay (LOSR) of 34.7 +/- 16.7 days, was NT$ 27,645 +/- 13,812. The FIM score improved from 56.8 +/- 24.2 on admission to 76.6 +/- 26.2 at discharge, with a rehabilitation efficiency index (EIR) of 0.7 +/- 0.7. Further analysis indicated that there were significant differences among the three disability groups on rehabilitation fees and LOSR while EIR was unaffected. The findings of this study suggest that FIM-FRGs can differentiate different rehabilitation needs in terms of rehabilitation fees and LOSR; therefore, a prospective case payment system based on FIM-FRGs is suggested for stroke rehabilitation reimbursement scheme in the future.

Alzheimer's disease: scintigraphic appearance of Tc-99m HMPAO brain spect

To investigate the value of Tc-99m hexamethylpropylene amine oxime (Tc-99m HMPAO) single photon emission computed tomography (SPECT) as a diagnostic test for Alzheimer's disease.

METHODS AND PATIENTS

Tc-99m HMPAO SPECT was performed on 140 patients and 20 controls. A final diagnosis was established for 115 patients, 58 of whom had Alzheimer's disease. The probability of AD was determined for seven scintigraphic patterns. The probability of Alzheimer's disease was 14% for patients with memory loss and normal perfusion. For patients with abnormal perfusion patterns, the probability of Alzheimer's disease was 87% with bilateral temporoparietal defects, 73% with bilateral temporoparietal defects plus additional defects, 62% with a unilateral temporoparietal defect, 33% with a frontal defect only, 0% with other large defects, and 0% with multiple small cortical defects. In 115 patients with the complaint of memory loss or cognitive abnormalities, bilateral temporoparietal hypoperfusion with or without additional hypoperfusion was more frequent than other scintigraphic patterns in patients with Alzheimer's disease. Tc-99m HMPAO SPECT offers the clinician the possibility of differentiating dementias on the basis of differences in perfusion patterns.

Apolipoprotein E polymorphism and Alzheimer's disease

We aimed to determine the association and related factors of the apolipoprotein E (ApoE) genotype and Alzheimer's disease (AD) in Taiwan. We examined ApoE genotypes in 50 Chinese patients with AD and 50 age- and sex-matched controls. The patients met the criteria of probable AD of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) and AD of the Diagnostic and Statistical Manual of Mental Disorders 4th edition (DSM-IV). There were 28 females and 22 males in the case and control groups. The mean age of onset of AD was 72. 62 years. The average interval between onset and research was 3.85 years. The frequency of ApoE epsilon 4 in the AD group was significantly higher than that in the controls (0.13 versus 0.02, p < 0.05). The odds ratio for AD in individuals with at least one ApoE epsilon 4 allele was 6.0 (95% CI 1.34 to 55.3, p < 0.001). The linear trend for AD in proportion to alleles of ApoE epsilon 4 was significant (chi 2 = 8.3, p = 0.004). The risk of ApoE epsilon 4 allele for the late-onset AD patients, males, or those who received less education was higher than that for the early-onset AD patients, females, or those who had received more education. The sensitivity of the epsilon 4 allele was 24%, the specificity 96%, the positive predictive value 86%, and the negative predictive value 56%. Our results supported that the ApoE epsilon 4 allele is related to AD in Taiwan. In addition, sex and education may play important roles in the presence of ApoE epsilon 4 allele. The epsilon 4 allele seemed helpful as an adjunct for diagnostic testing of AD.

Behavioral disorders and caregivers' reaction in Taiwanese patients with Alzheimer's disease

OBJECTIVES

To evaluate the applicability of the Chinese version of the Neuropsychiatric Inventory Scale (NPI), and to explore the neuropsychiatric manifestations of Taiwanese patients with Alzheimer's disease (AD) and caregiver distress.

METHOD

The Mini-Mental State Examination (MMSE) was administered to 95 patients with AD, and their caregivers were interviewed with the NPI. To assess the test-retest reliability of the Chinese version of the NPI, 86 caregivers underwent a second NPI 3 weeks later.

RESULTS

The Cronbach's alpha coefficient of the Chinese version of the NPI was .76. The test-retest reliabilities of frequency, severity, and caregiver burden scores were significantly correlated; overall correlations were .85 for frequency (p < .001), .82 for severity (p < .001), and .79 (p < .001) for distress. Factor analysis was carried out, and three groups, "mood and psychosis," "psychomotor regulation," and "social engagement," were found. Aberrant motor behavior was the most frequently recorded behavior; euphoria was the least. There was no significant correlation between the patient's MMSE and the caregiver distress score, except for aberrant motor activity (r = -.23, p = .03). The symptoms most frequently reported to be severely distressing to caregivers were aberrant motor activity, anxiety, agitation, and delusions.

CONCLUSIONS

These results indicate that the NPI is a reliable tool to assess behavioral disturbance and caregiver distress in Taiwanese AD patients. These findings also confirm the high prevalence of psychopathology among AD patients and the marked distress produced by many of these behaviors.

Factors influencing functional independence outcome in stroke patients after rehabilitation

The purpose of this study was to identify predictive variables relevant to functional independence outcomes for stroke patients following rehabilitation therapy. We prospectively studied 150 stroke patients consecutively admitted to the inpatient rehabilitation department of a university hospital from January 1 to December 31, 1997. Functional ability was assessed with the Functional Independence Measure (FIM) instrument on admission, on discharge of inpatient rehabilitation program, and at the 6 months follow-up visit after discharge. Severity of stroke was determined by using the Canadian Neurological Scale (CNS) on admission. In addition, major medical and sociodemographic factors were documented during hospitalization as independent variables. Of the 142 subjects surveyed, 23 (16.2%) stroke patients achieved functional independence at home when re-visited. Univariate test and multiple logistic regression analyses indicated that the significant factors affecting functional independence included age of onset, occupation, prior heart problems, the presence of medical complications, bilateral hemiplegia, and the functional ability (FIM score) and the severity of stroke (CNS score) on admission. The results of this study suggest that the admission CNS and FIM scores are useful in the prediction of functional independence outcome for stroke survivors following rehabilitation therapy.

Efficiency and effectiveness of stroke rehabilitation after first stroke

PURPOSE

To investigate predictive variables of rehabilitation efficiency and achievement of rehabilitation potential following stroke rehabilitation.

METHODS

We prospectively studied 110 first-stroke patients consecutively admitted to the inpatient rehabilitation department of our university hospital from 1 January to 31 December 1997. Functional recovery was measured as improvement in the ability to perform the Functional Independence Measure (FIM) instrument. Major medical (side of paralysis, stroke etiology, risk factors, Brunnstrom motor recovery stage, etc.), rehabilitative (initial FIM subscore, interval from stroke onset to rehabilitation commencement, rehabilitation stay, etc.), and demographic (age, years of education, occupation, marital and living status, care-giver, etc.) variables were examined.

RESULTS

The mean FIM score was 57.7 +/- 24.5 at admission and 77.3 +/- 26.3 at discharge. The mean rehabilitation efficiency (0.7 +/- 0.7) and effectiveness (30.6 +/- 24.0%) of stroke rehabilitation were determined. Rehabilitation efficiency and rehabilitation effectiveness were significantly predicted by length of stay and arm motor recovery stage, and by age and arm motor recovery stage, respectively. The variance explained only 21% of the rehabilitation efficiency and 24% of the achievement of rehabilitation potential.

CONCLUSIONS

The results of this study suggest that the large proportion of the unexplained variance in rehabilitation efficiency and effectiveness is due to nonmedical factors influencing the selection of patients for rehabilitation.

JC virus binds to primary human glial cells, tonsillar stromal cells, and B-lymphocytes, but not to T lymphocytes

The human polyomavirus, JCV, is the etiological agent of the fatal central nervous system demyelinating disease, progressive multifocal leukoencephalopathy (PML). In PML patients, JC Virus (JCV) can be detected in glial cells in the central nervous system (CNS); in B-lymphocytes in the peripheral blood, bone marrow, spleen, and tonsil; and in tonsillar stromal cells. In vitro, JCV infects glial cells, tonsillar stromal cells, and to a limited extent B-lymphocytes. The presence or absence of as yet unidentified cell type specific transcription factors contributes to the restricted tropism of JCV for these cell types. However, several studies indicate that cell surface receptors may also contribute to the limited host range of JCV. To examine this latter possibility we measured the binding of purified JCV virions to primary cultures of glial cells, tonsillar stromal cells, peripheral blood lymphocytes, and to several established cell lines. Our results demonstrate that JCV binds to primary glial cells, stromal cells, and B cells, but does not bind to primary T cells. In contrast, JCV bound to all cell lines tested, including the Namalwa B cell line and the Jurkat T cell line. These data are novel and demonstrate that JCV selectively interacts with cells in vivo that are known to be susceptible to infection. This selectivity appears to be lost when one examines virus binding to a variety of human, monkey, or mouse tumor cell lines. We next examined the susceptibility of primary peripheral blood lymphocytes and the Namalwa B cell line to infection with JCV. Our results demonstrate that the majority of infectious JCV virions remain cell surface associated and do not efficiently establish infection of B cells. This may explain the in vivo observation that JCV DNA is frequently detected in association with lymphocytes by PCR but that JCV mRNA is rarely detected in association with lymphocytes by reverse transcriptase PCR. These results also confirm previous data regarding the association of JCV with human B cells in vivo and support the hypothesis that B cells may be involved in trafficking of JCV to the CNS.

The recovery potential of central conduction disorder in hypothyroid rats

In an aim to detect the dysfunction of central nervous system among rats with varied durations of hypothyroidism and to elucidate the recovery potential after thyroxine replacement, a series of BAEP were conducted and compared with age-matched controls. BAEP was performed in five groups of the hypothyroid animals 1, 3, 5, 7, and 9 months after thyroidectomy respectively. Following initial electrophysiological assessment, thyroxine replacement was administered to each group of hypothyroid rats, and BAEP was performed at two month intervals, up to two successive normal studies or six months after the initiation of therapy, whichever came first. Before thyroxine treatment, prolonged I-V interpeak latency was the most consistent abnormal finding in all groups of hypothyroid rats, and longer hypothyroid state correlated well with more severe central conduction disorder. Hearing impairment was also noted among those with long duration of hypothyroidism. After thyroxine replacement, the central conduction dysfunction usually returned to normal if the hypothyroid state was not more than 5 months in duration. However, when hypothyroid state persisted over 7 months or more, there would be an incomplete recovery for central conduction disorder. The present study brings out the concept of 'therapeutic window' in reversing the central nervous dysfunction caused by hypothyroidism in adult rats.

Hypothyroid myopathy-pathological and ultrastructural study

Seventeen patients with hypothyroid myopathy were studied before and after thyroxine (T4) treatment. The severity of clinical myopathy was assessed with the aid of a modified rating scale. Laboratory findings including thyroid function, serum creatine kinase (CK), and electromyography were assessed at regular time intervals until a final muscle biopsy was performed. The average period of follow-up was 1.8 years. The authors emphasize: 1) in skeletal muscle pathology of hypothyroidism, the fiber atrophy and increased central nuclear counts are evidence of clinical myopathy during thyroxine treatment; 2) in ultrastructural pathology, the abnormal glycogen accumulation accounts largely for clinical severity and its ongoing resolution is parallel to steady amelioration following T4 therapy, while mitochondrial abnormalities are insignificant in clinical correlation and probably become permanent in some cases with prolonged hypothyroidism; and 3) serial needle biopsies of skeletal muscle are impractical for long-term study of hypothyroid myopathy, but they may be reserved for those patients with a sustained myopathic complaints on T4 therapy.

The relation between admission balance and functional outcomes following stroke rehabilitation: a medical center based study

This prospective study evaluated the clinical use of the Fugl-Meyer Balance Scale (FMBS) on stroke patients during hospitalization and assessed the relationship between balance score at admission to the rehabilitation program and functional outcome at discharge. One hundred and sixty-three stroke patients admitted to the in-patient rehabilitation department of a university-based medical center between January 1 and December 31, 1997 were recruited for this investigation. Functional ability was evaluated with the Functional Independence Measure (FIM) instrument, and balance was measured using the 7-item Fugl-Meyer Balance Scale. These measures were assessed both at admission to and discharge from the inpatient rehabilitation program. Pearson correlation and multiple regression analyses were used to determine the relationship between balance and functional ability scores at admission and rehabilitation outcomes at discharge, including length of stay, functional gain, and efficiency. The results demonstrated that the balance score at admission accounted for 6% of the variation in length of stay, once demographic influences were controlled. The FIM efficiency score could possibly be predicted by the balance ability at admission, which accounted for 3% of the variance. However, the balance score could not provide predictive information about the FIM gain beyond that already provided by the FIM score at admission, which accounted for 4% of the variance with demographic factors controlled. Overall, balance ability at admission, assessed by the Fugl-Meyer Balance Scale, had no or at least only little, contribution to account for the variance in rehabilitation outcomes. These findings suggest that the use of Fugl-Meyer Balance Scale at admission to stroke inpatient rehabilitation seemed not to enhance the ability to predict rehabilitation outcomes.

The influence of rehabilitation therapy on the prognosis for stroke patients--a preliminary study

The purpose of this prospective study was to investigate the influence of rehabilitation therapy on the prognosis for stroke patients. Sociodemographic and clinical factors were collected in a sample of 147 stroke patients (81 men and 66 women) admitted to the inpatient rehabilitation department at our university hospital over 10 days between January 1, 1997 and December 31, 1997. Functional Independence Measure (FIM) scores at discharge and gains during rehabilitation period were used as the prognosis index. Statistical techniques with univariate and multiple regression analyses indicated that significant predictors of discharge FIM scores include age, previous attacks twice or over, medical comorbidities, sensory and orientation impairments, and dementia. In addition, previous stroke attacks twice or over and sensory impairment were significant predictors of FIM gains during rehabilitation period. We concluded that: 1) age is a critical factor to determine the rehabilitation outcome, but may not be an important factor to predict the ability for the improvement through rehabilitation therapy; 2) the delay of rehabilitation therapy may not affect the potential for further improvement; 3) patients with low initial functional level may have poor final outcome, they may still have good rehabilitation potential to improve the functional level; 4) complications of stroke may affect the rehabilitation outcome and should be prevented; and 5) patients with impaired mental status should not routinely be excluded from rehabilitation programs.

[A central nerve conduction study in hypothyroidism: before and after thyroxine replacement]

Employing a Nicolet CA 100 machine, 20 patients of primary hypothyroidism were selected for electrophysiological studies, including somato-sensory evoked potential (SSEP), brainstem auditory evoked potential (BAEP), and visual evoked potential (VEP), to assess the central nerve conduction before and after administration of the thyroid hormone. Before thyroxine replacement therapy, the latencies of N9, N13, and N20 in SSEP showed significant delay, while the central conduction time (CCT) merely had a tendency of prolongation. In BAEP, the peak and interpeak latencies delayed significantly. Additionally, the latency and amplitude of VEP also had significant difference between patients and controls. After thyroxine replacement, the SSEP, BAEP, and VEP studies revealed significant improvement, in correlation with clinical amelioration. In conclusion, the central nerve conduction would be affected in primary hypothyroidism and the improvement was usually the case, reflecting the clinical recovery after appropriate treatment. The electrophysiological study provides an objective method for monitoring the function of central nervous system in hypothyroidism before and after thyroxine treatment.

Prevalence and subtypes of dementia in southern Taiwan: impact of age, sex, education, and urbanization

To determine the prevalence and subtypes of dementia in southern Taiwan, a two-phase study consisting of a phase I screening survey using the Mini-Mental Status Examination (MMSE) and a phase II diagnostic examination using the CERAD neuropsychological battery and the neurobehavioral examination was conducted. According to the household records, stratified random sampling by the degree of urbanization of the community was used, and 2915 inhabitants aged 65 and over participated in this study. The ICD-10NA criteria for dementia, NINCDS-ADRDA guidelines for Alzheimer's disease (AD), and NINDS-AIREN criteria for vascular dementia (VaD) were employed. Three hundred and ninety-eight persons who had MMSE scores below the cutoff values were recruited into the phase II study, of whom 108 had dementia. The prevalence rate (PR) of dementia was 3.7%, increasing from 1.3% in people 65-69 years old to 16.5% in people 85 years old and older. The age-standardized PR (ASPR) was 4.0%. AD (58 cases, 53.7%, PR=2.0%, ASPR=2.3%) was the most common cause of dementia, followed by VaD (25 cases, 23.1%, PR=0.9%, ASPR=0.9%), and mixed dementia (eight cases, 7.4%). After adjusting for age, sex and education using logistic regression analysis, aging was a significant risk factor for AD, VaD and total dementia. Female sex and illiteracy were significant risk factors for AD only. We concluded that the prevalence of dementia in Taiwan is lower than in the developed countries, which could be due to a relatively young elderly population and a high mortality from dementia in Taiwan. AD is the leading cause of dementia in Taiwan. Considering the high stroke prevalence, the relatively lower prevalence of VaD in Taiwan deserves further investigation.

Incidence and subtypes of dementia in southern Taiwan: impact of socio-demographic factors

OBJECTIVE

To determine the incidence rate (IR) and subtypes of dementia in southern Taiwan.

METHODS

From a cohort of 2,915 community inhabitants aged 65 years and over, 2,507 and 2,175 subjects participated in the first- and second-year follow-up surveys, respectively. A two-phase study used the Mini-Mental State Examination in phase I and the Consortium to Establish a Registry of Alzheimer's Disease (CERAD) neuropsychological battery and the neurobehavioral examination in phase II. We applied International Classification of Diseases (ICD)-10NA criteria for dementia, National Institute of Neurological and Communication Disorders and Stroke-Alzheimer's Disease and Related Disorders Association (NINCDS-ADRDA) guidelines for Alzheimer's disease (AD), and National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN) criteria for vascular dementia (VaD).

RESULTS

The annual IR for total dementia was 1.28%, which increased with age from 0.77% for 65- to 74-year-olds to 6.19% for persons aged 85 years or older. AD (25 cases, 41.7%, IR=0.54%) was the most common cause of dementia, followed by VaD (19 cases, 31.7%, IR=0.41%) and mixed dementia (9 cases, 15.0%). After adjusting for sex, increasing age was significantly associated with total dementia and AD (p < 0.01). Illiteracy was associated with a marginally increased risk for total dementia (aRR=1.59, p < 0.1) as was being female for AD (aRR = 1.92, p < 0.1). The 2-year mortality rate was high among the demented (48% in total dementia, 38% in AD, and 60% in VaD).

CONCLUSIONS

The age-specific incidence of dementia in Taiwan is approaching that of developed countries and the low prevalence of dementia (especially VaD) may be mainly due to the high mortality. Age was the major risk factor for total dementia and AD. Being female was probably a risk factor for AD, as was illiteracy for total dementia.

Infection of glial cells by the human polyomavirus JC is mediated by an N-linked glycoprotein containing terminal alpha(2-6)-linked sialic acids

The human JC polyomavirus (JCV) is the etiologic agent of the fatal central nervous system (CNS) demyelinating disease progressive multifocal leukoencephalopathy (PML). PML typically occurs in immunosuppressed patients and is the direct result of JCV infection of oligodendrocytes. The initial event in infection of cells by JCV is attachment of the virus to receptors present on the surface of a susceptible cell. Our laboratory has been studying this critical event in the life cycle of JCV, and we have found that JCV binds to a limited number of cell surface receptors on human glial cells that are not shared by the related polyomavirus simian virus 40 (C. K. Liu, A. P. Hope, and W. J. Atwood, J. Neurovirol. 4:49-58, 1998). To further characterize specific JCV receptors on human glial cells, we tested specific neuraminidases, proteases, and phospholipases for the ability to inhibit JCV binding to and infection of glial cells. Several of the enzymes tested were capable of inhibiting virus binding to cells, but only neuraminidase was capable of inhibiting infection. The ability of neuraminidase to inhibit infection correlated with its ability to remove both alpha(2-3)- and alpha(2-6)-linked sialic acids from glial cells. A recombinant neuraminidase that specifically removes the alpha(2-3) linkage of sialic acid had no effect on virus binding or infection. A competition assay between virus and sialic acid-specific lectins that recognize either the alpha(2-3) or the alpha(2-6) linkage revealed that JCV preferentially interacts with alpha(2-6)-linked sialic acids on glial cells. Treatment of glial cells with tunicamycin, but not with benzyl N-acetyl-alpha-D-galactosaminide, inhibited infection by JCV, indicating that the sialylated JCV receptor is an N-linked glycoprotein. As sialic acid containing glycoproteins play a fundamental role in mediating many virus-cell and cell-cell recognition processes, it will be of interest to determine what role these receptors play in the pathogenesis of PML.

A study of central and peripheral nerve conduction in patients with primary hypothyroidism: the effects of thyroxine replacement

Somato-Sensory Evoked Potential (SSEP) and Peripheral Nerve Conduction (PNC) studies were performed in twenty patients with primary hypothyroidism to elucidate the changes of central and peripheral nervous systems in hypothyroid state and the effects of thyroxine replacement. Before thyroxine replacement therapy, eleven patients had significantly delayed SSEP (prolonged latencies of N9, N13, or N20), and only three patients had prolonged central conduction time (between N13 and N20). PNC abnormalities with decreased conduction velocity and diminished amplitudes were found in fourteen patients. After thyroxine treatment, both SSEP and PNC studies demonstrated significant improvement and paralleled the clinical neurological amelioration. The central and peripheral conduction velocities returned to normal limits, while the abnormality in amplitude still persisted. There were also discrepancies between SSEP and PNC studies in both the abnormality pattern and the recovery potential. Our observations may suggest: firstly, both the SSEP and PNC studies may be useful, alternative tools in monitoring the neurological disorders in hypothyroidism; and secondly, the pathogenesis of central and peripheral nervous dysfunction in hypothyroidism may be via different mechanisms.

Cranial computed tomography in ischemic stroke patients with and without dementia--a prospective study

Stroke patients were assessed by brain CT scan, accompanied by demographic and clinical factors to predict the development of dementia following an ischemic episode. Vascular dementia was defined by NINDS-AIREN criteria. From 50 demented and 50 non-demented stroke patients, we analyzed the location of lesion, counted the numbers of lacunae, and semiquantitatively assessed the size of infarction, severity of overall white matter lesions (WML), and degree of brain atrophy. Compared to the non-demented patients, the demented patients: 1) encountered more stroke episodes (p < 0.001); 2) had more lacunae at bilateral basal ganglion (p < 0.001) or thalamus (p < 0.01); and 3) tended to have lesions in left cortex (p < 0.001), particularly a large infarct at the parietal (p < 0.001) or temporal lobe (p < 0.001). Periventricular changes (p < 0.001), subcortical WML (p < 0.001), overall WML (p < 0.001), and brain atrophy (p < 0.05) were also more severe in the demented group. However, no difference existed in demographic factors between the two groups. We concluded that several factors were important in developing dementia following an ischemic stroke, and the order by logistic regression would be: the severity of overall WML, left parietal infarct, and numbers of thalamic lacunae.

The human polyomavirus, JCV, does not share receptor specificity with SV40 on human glial cells

The initial event in the life cycle of a virus is its interaction with specific receptors present on the surface of a cell. Understanding these interactions is important to our understanding of viral tropism and tissue specific pathology associated with viral disease. The human polyomavirus, JCV, is the etiological agent of the fatal central nervous system (CNS) demyelinating disease, progressive multifocal leukoencephalopathy (PML). PML is the direct result of JCV infection of oligodendrocytes, the myelin producing cell in the CNS. In vivo, JCV can be detected in oligodendrocytes, astrocytes, lymphoid tissue, and peripheral blood of PML patients. In vitro, JCV infects human glial cells, tonsilar stromal cells, and, to a limited extent, human B lymphocytes. The initial step in infection of cells by JCV is at the level of attachment and entry. A specific cell surface receptor for JCV on human glial cells has not been identified. To begin to understand the nature of JCV receptors on human glial cells, large quantities of a previously characterized hybrid JC virus (Mad-1/SVEdelta) were purified. A direct virus binding assay demonstrated that these highly purified and labeled JCV virions bound to a finite number of cellular receptors on human glial cells. A competitive virus binding assay demonstrated that an excess of unlabeled JCV competed with labeled JCV more efficiently than did an excess of purified SV40. Furthermore, anti-class I antibodies which inhibited infection of glial cells by SV40 had no significant effect on infection by JCV. These results imply that JCV does not share receptor specificity with the related polyomavirus, SV40.

A longitudinal study of central and peripheral nerve conduction in hypothyroid rats

In order to detect the dysfunction of central and peripheral nervous systems among rats with varied duration of hypothyroidism and to elucidate the pattern of recovery after thyroxine replacement, a series of BAEP and PNCS (Peripheral Nerve Conduction Study) were conducted and compared with age-matched controls. BAEP and PNCS were performed in three groups of hypothyroid animals 1, 3 and 5 months after thyroidectomy, respectively. Following initial electrophysiological assessment, thyroxine replacement was administered to each group of hypothyroid rats, and BAEP and PNCS were performed at two month intervals, up to two successive normal studies, or six months after the initiation of therapy, whichever came first. For BAEP, prolonged I-V interpeak latency was the most consistent abnormal finding in all groups of hypothyroid rats, and longer hypothyroid states correlated well with more severe central conduction disorder. Nevertheless, these abnormalities usually returned to normal after thyroxine replacement if the duration of hypothyroidism was less than 5 months. Regarding PNCS, all groups of thyroidectomized rats showed normal conduction before and after thyroxine therapy. The present study indicates that, in rats: (1) the peripheral nervous system seems to be more resistant to hypothyroidism than the central nervous system, or (2) the pathogenesis of central and peripheral nerve dysfunction in hypothyroid rats may occur through different mechanisms.

The psychiatric manifestation of Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is considered to be very rare in the population, and the psychiatric manifestation of the disease even rarer with only one report in the past few years in Taiwan. To clarify whether the psychiatric manifestation of CJD is really rare or whether it is neglected in Taiwan, the authors reviewed the discharge notes of patients who had been admitted to a neurological unit in the past 15 years and conducted a chart review of the patients of CJD supported by the clinical courses, EEG finding and brain biopsies. An inquiry was made by telephoning their families to follow up their condition after discharge. Five of the 8 cases with CJD had psychiatric symptoms including changes of mood, thought, behavior and perception during their course of illness. Four cases had been sent to the psychiatric unit and received treatment under several kinds of psychiatric diagnoses. Two patients had been admitted to the psychiatric unit and one had received electroconvulsive treatment. Two of the patients had been suspected to be the victims of neuroleptic malignant syndrome. It is likely that it is psychiatrists who will meet CJD patients first in the early stages of disease. CJD should be kept in mind and EEGs with detailed neurological checkups should be completed, if the cognitive functions of the patients with unusual neurological symptoms deteriorate quickly and their psychiatric symptoms fail to respond to any treatment.

Prevalence of dementia in an urban area in taiwan

This two-stage epidemiologic study was to investigate the prevalence and types of dementia among elderly people in the Saa-Min district of Kaohsiung City in Taiwan. In stage one, the Chinese Mini-Mental Status Examination (CMMSE) and Blessed Dementia Rating Scale were employed. In stage two, a comprehensive neurobehavioral examination and neuropsychologic tests were administered by neurologists and neuropsychologists. Dementia was defined by DSM-III-R criteria. The National Institute of Neurological and Communication Disorders and Stroke-Alzheimer's Disease and Related Disorders Association guidelines for Alzheimer's disease (AD) and the National Institute of Neurological Disorder and Stroke-Association international pour la Recherche et l'Enseignement en Neurosciences criteria for vascular dementia (VaD) were applied. A total of 1,016 randomly selected elderly people participated in phase one: 131 people with CMMSE below cutoff values participated in phase two, of whom 45 were confirmed to have a form of dementia. The prevalence of dementia in this sample was 4.4% (3.2% in men and 5.8% in women): 2.0% for those 65 to 74 years old, 8.3% for those 75 to 84 and 24.4% for those > or = 85 years old; 6.0% for those who were illiterate, 3.3% for those who attended grade-school; and 2.8% for those who finished junior-high-school. AD (22 cases, 48.9%) was the most common cause of dementia, followed by VaD (11 cases, 24.4%) and mixed dementia (MIX: 5 cases, 11.1%). Old age and being female were significant high risk factors for AD. Medical history indicated that stroke and hypertension were significant risk factors for VaD. A relatively high prevalence of dementia was observed in this study, probably because we assessed neurobehavior in great detail. Although AD was the leading cause of dementia in the present population sample. VaD and MIX also comprised an important proportion, reflecting the high prevalence of stroke in Taiwan. Older women had high risk for AD, not for VaD; and those with a history of stroke and hypertension had high risk for VaD, not for AD.

[The changes of central and peripheral nerve conduction and the effect of thyroxine replacement in thyroidectomized rats]

The aim of this study is to make serial BAEPs and PNCS in hypothyroid rats in order to provide objective and quantitative methods of detecting dysfunction of the central and peripheral nervous system in hypothyroid status and elucidating the relationship between the recovery potential and the duration of hypothyroid status. Thyroidectomy was performed in eighteen naive 5-month-old Sprague-Dawley rats in order to induce hypothyroid status, which was confirmed by RIA study 1-2 months after the surgery. Initial BAEP and PNCS were performed in two groups of the hypothyroid animals 1 and 3 months after thyroidectomy. Following the initial examination, thyroxin replacement therapy was given to each hypothyroid group, and then followed by BAEPs and PNCS at two month intervals, up to twice normal studies or six months after the initiation of therapy. In the BAEP study, the prolonged I-V inter-peak latency was the most consistent abnormal finding in all hypothyroid rats. Delayed peak latencies as well as prolonged I-III and III-V inter-peak intervals occurred when the hypothyroid status was longer than one month. We noted that the longer the hypothyroid status, the more severe the central conduction dysfunction. Nonetheless, these abnormalities always returned to normal after the replacement therapy if the hypothyroid state was shorter than 3 months in duration. For the PNCS study, all groups of thyroidectomized rats showed the normal results. We think the peripheral nervous system of rats may be more resistant to damage by hypothyroidism than the central nervous system.

MR imaging evaluation of bone marrow signal change in post-irradiation patients with nasopharyngeal carcinoma

BACKGROUND

The normal distribution of red and yellow marrow can be altered by therapeutic irradiation, which causes a well-documented sequence of bone marrow changes. This study measured the T1 signal intensity of the clivus and cervical vertebral bodies of NPC patients who had received a complete course of radiation therapy.

METHODS

There were 3 categories of patients: Group I: NPC patients who had radiation myelitis; 14 persons which a total 20 times of MRI. Group II: NPC patients, without radiation myelitis; 6 patients, which a total 6 times of MRI. Group III (control group): patients who received MRI of the cervical spine because of cervical spondylosis or HIVD, were total of 45 patients. In the sagittal section of T1WI, the signal intensity of the bone marrow of clivus and C2 to T1 vertebral bodies was measured.

RESULTS

1). There were homogeneous increases of signal intensity of the bone marrow of clivus and C2 to T1 in Groups I and II. 2). There was no statistical difference between Groups I and II. 3). The increased signal intensity of bone marrow after radiation showed no difference in short and long duration between radiation therapy and MR examinations, indicating that bone marrow signal intensities were increased in NPC patients whether or not they had radiation myelitis.

CONCLUSIONS

Signal change in bone marrow may have occurred soon after radiation therapy, and may have persisted for several years. The radiation myelitis always involved the low medulla oblongata to C5 level; however, the bone marrow signal change always extended downward to the T1 level, so bone marrow is more sensitive than the spinal cord and is prone to be affected by irradiation.

Types of dementia in Taiwan--a prospective study

We prospectively investigated 100 consecutive inpatients with suspected dementia to evaluate the relative frequency of various types of dementia in a general hospital of Taiwan. Dementia was confirmed in 86 cases (86%) according to the dementia criteria of the third revised edition of the Diagnostic and Statistical Manual of Mental Disorders and Clinical Dementia Rating Scale (greater than or equal to 1). In contrast to the western developed countries, vascular dementia (VD) (35%) was the leading type of dementia, followed by Alzheimer's disease (AD) (27%), mixed VD and AD (MIX) (14%), and other degenerative diseases (10%). Ten cases (11.6%) of potentially treatable dementia were identified and 8 of 10 had good improvement after appropriate treatment. There were significant age differences among patients with MIX, AD and VD (p less than 0.01). Those with MIX were the oldest (72.12 +/- 9.4) followed by AD (69.70 +/- 8.52) and VD (64.81 +/- 9.12). Males were slightly predominant in this series (male:female = 50:36). A comprehensive clinical investigation including laboratory tests, electroencephalography and CT are necessary in the assessment of demented patients in order to make correct etiological diagnoses which lead to appropriate treatment or management of this terrifying syndrome.

A quantitative MRI study of vascular dementia

We studied the MRI and clinical factors associated with dementia following stroke by quantifying ventricle-to-brain ratio (VBR), anatomic region of infarction, and cortical, subcortical, and white matter areas of infarction in 24 stroke patients with dementia and 29 nondemented stroke patients. The factors that most strongly correlated with dementia were total white matter lesion (WML) area, left WML, VBR, right WML, age, left cortical infarction area, left parietal infarction area, and total infarction area. Using discriminant analysis, these factors correctly classified 28 of 29 nondemented patients and 18 of 24 demented patients. Both cortical and white matter total infarction area measurements were strongly associated with dementia in stroke patients, suggesting that these factors strongly influenced the development of dementia following stroke. There was a strong association between dementia and left- but not right-hemisphere infarction area. The only demographic factor that strongly associated with dementia was age.

Watershed infarcts, Tc-99m HMPAO SPECT and CT correlation. Case reports

We report on the use of Tc-99m hexamethylpropylene amineoxime (HMPAO) in watershed infarcts in five patients who had focal neurologic symptoms. Good correlation between Tc-99m HMPAO and CT was found in two patients. In three patients only Tc-99m HMPAO SPECT in a watershed distribution showed a perfusion abnormality that explained the clinical findings. Tc-99m HMPAO SPECT may be more sensitive than CT in the detection of infarctions in the watershed distribution.

[The effects of metrizamide myelography on electroencephalographic changes]

Metrizamide, a non-ionic water soluble contrast medium, is used in myelography for detecting spinal cord lesions. Because it is an injection in the subarachnoid space, the effects on the central nervous system following metrizamide myelography should be studied. Electroencephalography can offer a non-invasive and objective method for evaluating the functions of the central nervous system. From September to December 1986, 30 cases which had received cervical or lumbar metrizamide myelography were collected. After myelography, in addition to a history review and neurologic examination, electro-encephalography was carried out within 24 hours. If the EEG record revealed abnormal, a series of EEG follow-ups were conducted until recordings were normal. The incidence of clinical adverse effects following Metrizamide myelography was 53.3% and 66.6% respectively in cervical and lumbar injections. No significant difference was found between the two groups. Secondly, the abnormal rate of the EEG record was 40.0% and 60.0% following cervical and lumbar myelography. The difference was also not significant. Lastly, the relation between clinical adverse effects and an abnormal EEG records was poor in cervical metrizamide myelography but good in lumbar myelography. The conclusions suggested by this research that the clinical adverse effects and the abnormal EEG record after metrizamide myelography are transient and are reversible changes. The mechanism of complications following cervical and lumbar metrizamide are different. Although complications may occur following cervical and lumbar metrizamide myelography, it remains a practical method in detecting spinal cord lesions.