Assessment of High Risk for Alzheimer's Disease Using Plasma Biomarkers in Subjects with Normal Cognition in Taiwan: A Preliminary Study

Background

In Alzheimer's disease (AD), cognitive impairment begins 10-15 years later than neurodegeneration in the brain. Plasma biomarkers are promising candidates for assessing neurodegeneration in people with normal cognition. It has been reported that subjects with the concentration of plasma amyloid-β 1-42×total tau protein higher than 455 pg²/ml² are assessed as having a high risk of amnesic mild impairment or AD, denoted as high risk of AD (HRAD).

Objective

The prevalence of high-risk for dementia in cognitively normal controls is explored by assaying plasma biomarkers.

Methods

422 subjects with normal cognition were enrolled around Taiwan. Plasma Aβ_1-40, Aβ_1-42, and T-Tau levels were assayed using immunomagnetic reduction to assess the risk of dementia.

Results

The results showed that 4.6% of young adults (age: 20-44 years), 8.5% of middle-aged adults (age: 45-64 years), and 7.3% of elderly adults (age: 65-90 years) had HRAD. The percentage of individuals with HRAD dramatically increased in middle-aged and elderly adults compared to young adults.

Conclusion

The percentage of HRAD in cognitively normal subjects are approximately 10%, which reveals that the potentially public-health problem of AD in normal population. Although the subject having abnormal levels of Aβ or tau is not definitely going on to develop cognitive declines or AD, the risk of suffering cognitive impairment in future is relatively high. Suitable managements are suggested for these high-risk cognitively normal population. Worth noting, attention should be paid to preventing cognitive impairment due to AD, not only in elderly adults but also middle-aged adults.

Investigation of the Number of Tests Required for Assaying Plasma Biomarkers Associated with Alzheimer's Disease Using Immunomagnetic Reduction

INTRODUCTION

Concentrations of plasma biomarkers associated with Alzheimer's disease have been reported to be as low as several tens of picograms/milliliter (pg/ml). However, in assays measuring these biomarkers, it is likely that repeated measurements are necessary to obtain reliable values.

METHODS

We performed assays as a single test or as duplicate, quadruplicate, fivefold and tenfold repeated tests, on samples spiked with different concentrations of amyloid β 1-40 (Aβ_1-40; 1-1000 pg/ml), Aβ_1-42 (1-30,000 pg/ml) and total Tau protein (T-Tau; 0.1-1000 pg/ml), with the aim to to calculate the coefficients of variation (CVs).

RESULTS

The results demonstrated common changes in the CVs with changes in the number of tests for a given sample: the CVs decreased with increases in the number of tests from one to ten. All CV values were distributed within the range of 0.35 to 15.5%; as such, the CV values were all lower than the acceptable value of 20%.

CONCLUSION

Based on this study, a single assay of Aβ_1-40, Aβ_1-42 and T-Tau, respectively, provides reliable results in terms of the measurement of that plasma biomarker.

Urban-rural differences in the prevalence and correlates of mild cognitive impairment in community-dwelling older adults in Taiwan: The EMCIT study

BACKGROUND

Taiwan is a rapidly aging society. The elderly with mild cognitive impairment (MCI) have increased risk of dementia, and this is a population-based report using standard neuropsychological tests and expert consensus diagnosis to assess the MCI prevalence and its associated factors in Taiwan.

METHOD

The Epidemiology of Mild Cognitive Impairment study in Taiwan (EMCIT) is a community-based, prospective cohort study. Independently-living individuals aged ≧60 years in a rural area (n = 122) and in an urban area (n = 348) of New Taipei City, Taiwan, completed detailed neuropsychological tests at the cohort baseline. Diagnosis of MCI was ascertained through expert consensus based on 2011 NIA-AA criteria.

RESULTS

Of 470 participants recruited between 2017 and 2019 (mean age 71.2 ± 5.4 years), the prevalence of MCI was higher in the rural area than in the urban area (25.1% vs. 10.8%, p < 0.001) after standardized for age, gender, and level of education. Having lower education and having depression symptoms were consistently associated with increased risk of MCI in both urban and rural areas (p < 0.05). Being male and diabetes were additionally associated with MCI prevalence in urban areas.

CONCLUSION

In this community-based prospective cohort study in Taiwan, the prevalence of MCI in the rural community was much higher than that in the urban community. Different strategies may be needed to targeted different types of communities.

Nanoparticle-based immunomagnetic assay of plasma biomarkers for differentiating dementia and prodromal states of Alzheimer's disease - A cross-validation study

Blood-based biomarker assays of plasma β-amyloid (Aβ) and tau have the advantages of cost-effective and less invasive for the diagnosis of Alzheimer's disease (AD). We used two independent cohorts to cross-validate the clinical use of the nanoparticle-based immunomagnetic assay of plasma biomarkers to assist in the differential diagnosis of early AD. There were in total 160 subjects in the derivation cohort, and 242 in the validation cohort both containing controls, mild cognitive impairment due to AD and AD dementia diagnosed according to the 2011 NIA-AA guidelines. The cutoff value for plasma Aβ_1-42 (16.4 pg/ml) performed the best in differentiating between controls and patients with prodromal or clinical AD, with 92.5% for positive percent agreement (PPA), negative percent agreement (NPA), and overall rate of agreement (ORA). Aβ_1-42 × tau (642.58) was useful for separating patients with dementia and prodromal states of AD, with 84.9% PPA, 78.8% NPA and 83% ORA.

Age-Dependent Relationship Between Plasma Aβ40 and Aβ42 and Total Tau Levels in Cognitively Normal Subjects

Both amyloid plaques and neurofibrillary tangles are pathological hallmarks in the brains of patients with Alzheimer’s disease (AD). However, the constituents of these hallmarks, amyloid beta (Aβ) 40, Aβ42, and total Tau (t-Tau), have been detected in the blood of cognitively normal subjects by using an immunomagnetic reduction (IMR) assay. Whether these levels are age-dependent is not known, and their interrelation remains undefined. We determined the levels of these biomarkers in cognitively normal subjects of different age groups. A total of 391 cognitively normal subjects aged 23–91 were enrolled from hospitals in Asia, Europe, and North America. Healthy cognition was evaluated by NIA-AA guidelines to exclude subjects with mild cognitive impairment (MCI) and AD and by cognitive assessment using the Mini Mental State Examination and Clinical Dementia Rating (CDR). We examined the effect of age on plasma levels of Aβ40, Aβ42, and t-Tau and the relationship between these biomarkers during aging. Additionally, we explored age-related reference intervals for each biomarker. Plasma t-Tau and Aβ42 levels had modest but significant correlations with chronological age (r = 0.127, p = 0.0120 for t-Tau; r = −0.126, p = 0.0128 for Aβ42), ranging from ages 23 to 91. Significant positive correlations were detected between Aβ42 and t-Tau in the groups aged 50 years and older, with Rho values ranging from 0.249 to 0.474. Significant negative correlations were detected between Aβ40 and t-Tau from age 40 to 91 (r ranged from −0.293 to −0.582) and between Aβ40 and Aβ42 in the age groups of 30–39 (r = −0.562, p = 0.0235), 50–59 (r = −0.261, p = 0.0142), 60–69 (r = −0.303, p = 0.0004), and 80–91 (r = 0.459, p = 0.0083). We also provided age-related reference intervals for each biomarker. In this multicenter study, age had weak but significant effects on the levels of Aβ42 and t-Tau in plasma. However, the age group defined by decade revealed the emergence of a relationship between Aβ40, Aβ42, and t-Tau in the 6th and 7th decades. Validation of our findings in a large-scale and longitudinal study is warranted.

Patterns of Chinese medicine use in prescriptions for treating Alzheimer's disease in Taiwan

BACKGROUND

Certain Chinese medicine (CM) herbs and acupuncture may protect against Alzheimer's disease (AD). However, there is a lack of research regarding the use of CM in patients with AD. The aim of this study was to investigate CM usage patterns in patients with AD, and identify the Chinese herbal formulae most commonly used for AD.

METHODS

This retrospective, nationwide, population-based cohort study was conducted using a randomly sampled cohort of one million patients, selected from the National Health Insurance Research Database between 1997 and 2008 in Taiwan. CM use and the top ten most frequently prescribed formulae for treating AD were assessed, including average formulae dose and frequency of prescriptions. Demographic characteristics, including sex, age and insurance level were examined, together with geographic location. Existing medical conditions with the behavioral and psychological symptoms of dementia, and medications associated with CM were also examined. Factors associated with CM use were analyzed by multiple logistic regressions.

RESULTS

The cohort included 1137 newly diagnosed AD patients, who were given conventional treatment for AD between 1997 and 2008. Among them, 78.2 % also used CM treatments, including Chinese herbal remedies, acupuncture and massage manipulation. Female patients (aOR 1.57 with 95 % CI 1.16-2.13) and those living in urban areas (aOR 3.00 with 95 % CI 1.83-4.90 in the middle of Taiwan) were more likely to use CM. After adjusting for demographic factors, AD patients suffering from the behavioral and psychological symptoms of dementia were more likely to seek CM treatment than those with no symptoms (aOR 2.26 with 95 % CI 1.48-3.43 in patients suffering more than three symptoms). Bu-Zhong-Yi-Qi-Tang and Ji-Sheng-Shen-Qi-Wan were the two formulae most frequently prescribed by CM practitioners for treating AD.

CONCLUSION

Most people with AD who consumed herbal products used supplement qi, nourish the blood, and quiet the heart spirit therapy as complementary medicines to relieve AD-related symptoms, in addition to using standard anti-AD treatments.

Clinical Dementia Rating Scale Detects White Matter Changes in Older Adults at Risk for Alzheimer's Disease

This study investigated the putative changes in regional gray matter and cingulum bundle segments in mild cognitive impairment (MCI) by using two diagnostic criteria. Participants comprised 50 older adults with MCI and 22 healthy older controls (HC). The older adults with MCI were further divided into two groups defined by a global Clinical Dementia Rating (CDR) score of 0.5 and with (the CDR/NPT MCI group) or without (the CDR MCI group) objective cognitive impairments determined using neuropsychological tests (NPTs). Comparable regional gray matter integrity was observed among the three groups. However, the integrity of the right inferior segment of the cingulum bundle in the two MCI groups was more reduced than that in the HC group, and the CDR/NPT MCI group exhibited additional disruption in the left inferior cingulum bundle. The results also demonstrated that neuropsychological measures have greater predictive value for changes in white matter beyond the contribution of an informant-based instrument alone. Overall, the findings confirm the utility of informant-based assessment in detecting microstructural brain changes in high-risk older adults, even before objective cognitive impairment is evident. The findings also suggest that combining the neuropsychological measures with the informant-based assessment provided the greatest predictive value in assessing white matter disruption. The essential role of the white matter measurement as a biomarker for detecting individuals at a high risk of developing dementia was highlighted.

Improvement of diagnostic rate of carpal tunnel syndrome with additional median-to-ulnar comparative nerve conduction studies

PURPOSE

The aim of this study is to assess whether additional median -to-ulnar comparative tests will improve the diagnostic rate of carpal tunnel syndrome (CTS).

METHODS

We recruited 248 hands of 162 CTS patients, and 166 hands of 83 controls. One hundred and sixty-eight (68%) symptomatic hands had abnormal median distal latencies or palm-wrist latencies. We performed three additional comparative tests in the remaining symptomatic hands and the non-CTS hands. The first test compared median distal motor latency (MDL) recorded from the second lumbrical muscle (2L) and ulnar distal latency recorded from interossei muscles (INT) (2L-INT). The second test compared median and ulnar antidromic sensory latencies (MS-US). And the third test compared median and ulnar nerve latencies in the palm-to-wrist segment (PM-PU).

RESULTS

In control subjects, upper limits of median-to-ulnar differences were: 2L-INT= 0.4 ms, MS-US= 0.5 ms, PM-PU= 0.4 ms. In CTS patients with normal conventional electrodiagnostic methods, MS-US difference showed the lowest sensitivity (21.3%). The diagnostic sensitivity of 2L-INT was 27.5% and PM-PU 47.5%. With PM-PU test, additional 15.3% diagnostic rate could be got.

CONCLUSION

For CTS patients with normal results from the standard methods, PM-PU is a good additional comparative test to further improve diagnostic rate.

Altered source-based EEG coherence of resting-state sensorimotor network in early-stage Alzheimer's disease compared to mild cognitive impairment

Although the altered coherence between cortical areas in Alzheimer's disease (AD) has been widely studied, it remains unclear whether the source-based coherence measures within sensorimotor network show significant difference between mild cognitive impairment (MCI) and AD. In the present study, resting-state electroencephalographic signals were recorded from 21 MCI and 21 mild AD patients. The spectral power and coherence in the sensorimotor areas were analyzed using the minimum norm estimate (MNE) combined with fast Fourier transform and coherence analysis in delta (1-4 Hz), theta (4-8 Hz), alpha (8-13 Hz), beta (13-25 Hz), and gamma (25-40 Hz) bands. Our results indicated that source-based coherence in AD showed increased delta coherences between the bilateral precentral, left supplementary motor area (SMA) and right precentral, and left SMA and right postcentral areas. However, no significant difference of spectral powers was observed between AD and MCI. To conclude, the phenotype conversion from MCI to AD may be associated with an altered connectivity of the sensorimotor cortical network. This is a promising finding; however, further large-scale studies are needed.

Altered oscillation and synchronization of default-mode network activity in mild Alzheimer's disease compared to mild cognitive impairment: an electrophysiological study

Some researchers have suggested that the default mode network (DMN) plays an important role in the pathological mechanisms of Alzheimer’s disease (AD). To examine whether the cortical activities in DMN regions show significant difference between mild AD from mild cognitive impairment (MCI), electrophysiological responses were analyzed from 21 mild Alzheimer’s disease (AD) and 21 mild cognitive impairment (MCI) patients during an eyes closed, resting-state condition. The spectral power and functional connectivity of the DMN were estimated using a minimum norm estimate (MNE) combined with fast Fourier transform and imaginary coherence analysis. Our results indicated that source-based EEG maps of resting-state activity showed alterations of cortical spectral power in mild AD when compared to MCI. These alterations are characteristic of attenuated alpha or beta activities in the DMN, as are enhanced delta or theta activities in the medial temporal, inferior parietal, posterior cingulate cortex and precuneus. With regard to altered synchronization in AD, altered functional interconnections were observed as specific connectivity patterns of connection hubs in the precuneus, posterior cingulate cortex, anterior cingulate cortex and medial temporal regions. Moreover, posterior theta and alpha power and altered connectivity in the medial temporal lobe correlated significantly with scores obtained on the Mini-Mental State Examination (MMSE). In conclusion, EEG is a useful tool for investigating the DMN in the brain and differentiating early stage AD and MCI patients. This is a promising finding; however, further large-scale studies are needed.

Midlife risk factors for subtypes of dementia: a nested case-control study in Taiwan

OBJECTIVE

To identify the midlife risk factors for subtypes of dementia newly developed later in life.

METHODS

A nested case-control study was conducted on 157 demented cases and 628 comparison cases selected from 40,636 men and women who were enrolled from 1982 to 1992. Four comparison cases were frequency-matched on age, time at enrollment (within 6 months), gender, and residential township. Midlife risk factors included vascular risk factors (body mass index [BMI], total cholesterol, total triglycerides, blood glucose, cerebrovascular accident [CVA] history, diabetes mellitus history, and hypertension history), cigarette smoking, and alcohol consumption. Dementia assessments were ascertained through the computerized data linkage from National Health Insurance Database from 2000 to 2002 and clinically confirmed by neurologists or psychiatrists. Conditional logistic regression analysis was used to estimate the matched odds ratio (OR) and its 95% confidence intervals (CI) for each risk factor.

RESULTS

A J-shaped relationship was observed between BMI (kg/m(2)) and dementia. The multivariate-adjusted ORs (95% CI) of developing dementia were 1.84 (1.02-3.33), 1.87 (1.08-3.23) and 2.44 (1.39-4.28), respectively, for BMIs of <20.5, 23.0-25.4, >or=25.5 compared with a BMI of 20.5-22.9 as the referent group (OR = 1.0). Similar findings were observed for Alzheimer disease (AD) and vascular dementia (VaD). The association between obesity (BMI >or=25.5) and both AD and VaD was statistically significant among cigarette smokers but not among nonsmokers. Additionally, history of CVA was a significant risk factor for VaD, but not for AD.

CONCLUSION

Being underweight, being overweight, and a cerebrovascular accident in midlife may increase the risk of dementia in late life.

Psychiatric morbidity in dementia patients in a neurology-based memory clinic

The behavioral and psychological symptoms of dementia (BPSD) often present major problems for patients and their caregivers. In the past, neurologists paid less attention to such symptoms than to the cognitive symptoms of dementia. This prospective study investigated the prevalence of psychiatric morbidity in a neurology-based memory clinic and the stress of caregivers. Our patients with dementia were found to have a high prevalence of BPSD. The most frequent were anxiety, apathy, and delusion; the most distressing to caregivers were agitation, anxiety, delusion, and sleep disturbance. Using Clinical Dementia Rating (CDR), we compared BPSD between patients with mild dementia and those with moderate dementia. Only hallucinations and agitation were different significantly. Moderate dementia patients experienced these symptoms more frequently. The high prevalence of these symptoms might be explained by the fact that the cognitive symptoms were neglected or no enough information were received by many family members of patients with dementia until their own life quality was interfered and then they began to seek medical help. These symptoms and their effect of caregiver distress can be effectively reduced by pharmacologic and nonpharmacoloic managements, caregiver-focused training and education. They can be better approached by assessing neuropsychiatric symptoms regularly, educating the general population better, and treating these patients earlier.

Sensory nerve conduction studies of the superficial peroneal nerve in L5 radiculopathy

BACKGROUND

Theoretically, sensory nerve action potential (SNAP) of the superficial peroneal nerve (SPN) should be preserved when L5 roots are damaged. Previous study indicated that SNAP of SPN was lost or reduced in amplitude in patiens with L5 radiculopathy. To address this issue, this study compared results of SPN sensory conduction studies between healthy subjects and patients with L5 radiculopathy.

METHODS

Ninety-four healthy subjects were enrolled and assigned to two age groups: group I (< or = 60 years, n=61) and group II (> 60 years, n=33). Forty-one patients with unilateral L5 radiculopathy were enrolled by our electrodiagnostic laboratory between July 2000 and July 2003 and assigned to two age groups: 60 years or below (n=19) and above 60 years (n=22).

RESULTS

SPN response was found to be abnormal in only 1.6% of group I healthy subjects, but absent or abnormal SPN response was noted in 21.1% of patients with L5 radiculopathy of the same age group (p=0.01). However, a greater proportion of (27.3%) our healthy subjects above 60 years had abnormal SPN responses. This proportion was similar to that of patients with L5 radiculopathy and abnormal SPN response (31.8%) (p=0.72).

CONCLUSIONS

SPN sensory responses are reliably obtained in most healthy subjects under 60 years of age. Absence of SNAP or reduced SNAP amplitude of SPN on the side of their lesions did not necessarily exclude the diagnosis of L5 radiculopathy in the patients under 60 years of age.

Lobar cerebral hemorrhage from amyloid angiopathy: clinical, neuroimaging, pathologic and outcome correlations

Cerebral amyloid angiopathy (CAA) contributes to sporadic lobar intracerebral hemorrhage in older patients, especially those who are more than 70 years old. In clinical practice, a diagnosis of CAA refers to the Boston Criteria, which requires that "definitive" cases be confirmed by pathologic evidence at autopsy. A "Probable" case, means that there is clinical support and that pathologic evidence is available by biopsy from the craniotomy for patients with severe lobar intracerebral hemorrhage. Cerebral amyloid that is deposited in cortical vessels is revealed by apple-green birefringence under polarized light using Congo-red stain. Rebleeding after a first primary intracerebral hemorrhage is common. This paper describes five cases of aged patients with lobar cerebral hemorrhage and craniotomy with hematoma evacuation and biopsy. Pathological results all showed amyloid angiopathy. Various outcomes are discussed, and the literature is reviewed. Findings show that although patients with CAA were at high risk of recurrent hemorrhage after surgery, the mortality rate was relatively low despite the severity of lobar intracerebral hemorrhage.

The occurrence of diabetic ketoacidosis in adults

OBJECTIVE

To analyze the occurrence of DKA in Chinese adults.

METHODS AND PATIENTS

We retrospectively reviewed the medical records of adults presenting with DKA in a tertiary referral center from January 1992 to December 1997. We classified these patients into 3 groups: type 1, type 2 and new-onset diabetes. Clinical features and follow-up treatment were analyzed.

RESULTS

One hundred and twenty patients with 141 episodes of DKA were included; 77 episodes (54.6%) were classified as being caused by type 2, 32 (22.7%) by type 1 and 32 (22.7%) by new-onset DM. The average age of type 2 patients was significantly higher. Of the 25 new-onset patients with follow-up for at least 12 months, 11 were not taking insulin. Of these 11 patients, 6 had a family history of DM and 5 had BMI greater than 26.4 kg/m2. The fasting plasma C-peptide values at various times of follow-up varied from 2.3 to 9.5 ng/ml in 6 of the 11 DKA-onset patients.

CONCLUSION

In type 2 patients, the occurrence of DKA is usually associated with old age and another severe illness. "DKA-onset type 2 DM" reported in African-Americans and in Japanese is also observed in Chinese.

Rate of 14CO2 production from variously labeled forms of [14C]glucose in human breast invasive ductal carcinoma tissues

To establish possible cancerous aggressiveness between the metabolism of variously labeled [14C]glucose in the human breast invasive ductal carcinoma (IDC) tissues, we measured the rates of 14CO2 production from those tissues by using radiorespirometry, expressing the results as initial velocity (V) in nanomoles of 14CO2 min-1 g-1 of fresh tissues. The Vc data were compared with results of the SBR system, which grades up from I to III. Vc,1 values measured with [1-14C]glucose increased from 1.99-2.82 for SBR I to 3.90-4.09 for SBR II, finally reaching 4.83-7.04 for SBR III, thus matching clearly the increase of IDC cancerous aggressiveness. Conversely, data obtained from [3,4-14C]glucose and [6-14C]glucose decreased with increasing cancer stage: i.e., with [3,4-14C]glucose, Vc,3,4 values were 5.79-9.34 for SBR I, 4.45-4.84 for SBR II, and 2.35-1.90 for SBR III; with [6-14C]glucose, the corresponding Vc,6 values were 1.34-1.90, 1.33-1.41, and 0.72-0.79. The Vn,1/Vn,6 ratios were close to unity for normal tissues and for noncancerous tissues surrounding SBRI tumors. For cancerous tissues, however, the Vc,1/Vc,6 ratios were 1.5, 2.9, and 6.1-9.8 in IDC tissues graded as SBR I, II, and III, respectively. The results suggest the possible use of radiorespirometry as a tool to assess IDC aggressiveness.

Usefulness of molecular testing in Huntington's disease

BACKGROUND

Uncertainty in diagnosing Huntington's disease (HD) may occur in the absence of a family history or typical movement disorders. HD is characterized by a progressive disturbance of typical movement disorders (i.e., chorea, athetosis), psychiatric symptoms (i.e., depression, insomnia, anxiety, suspiciousness), and cognitive deterioration, in the absence of a dominant family history of similar disorders. Often, some of these symptoms are missing, which makes the diagnosis difficult. In recent years molecular testing has become the gold standard for diagnosing HD. Diagnostic accuracy for HD on genetic screening of patients and their families is important. We evaluated a polymerase chain reaction (PCR) technique for the detection of CAG trinucleotide repeats in the Huntington IT15 gene on chromosome 4 for the diagnosis of HD.

METHODS

A segment of the Huntington gene was amplified by PCR using the primers HD-1 and HD-3 flanking the CAG repeat sequence. Genomic PCR was performed on DNA extracted from the peripheral leukocytes of 12 patients from three unrelated families. One family had no documented history of movement or mental disorders, while the other two did. These two, therefore, required pre-symptomatic testing and exclusion of diagnosis in a seemingly symptomatic case.

RESULTS

We successfully identified four subjects with expansion of CAG trinucleotide repeats in Huntington gene IT15 on chromosome 4. Movement disorder was present in three of these subjects. One was the sister of subject 4, who was asymptomatic. A sister of subject 9 was ruled out from having HD by PCR despite having depression symptoms, which are frequently seen in HD patients.

CONCLUSIONS

Genetic testing is of prime importance in the establishment of an accurate diagnosis of Huntington's disease, especially in "sporadic" cases and presymptomatic family members, and for the exclusion of HD in family members with equivocal symptoms.

A proposed estimate of the tumor aggressiveness of human breast cancer using radiorespirometry

The relationships between carcinomatous aggressiveness and the glucolytic metabolism, namely the rate of 14CO2 production from [U-14C] glucose, are obtained from human breast tissues using radiorespirometry. The values are estimated as the initial velocity (V) expressed in eta 14CO2 x min-1 x g-1 of fresh tissues by [U-14C] glucose metabolism. The aggressiveness of the breast carcinomatous is diagnosed by the SBR grade system. As two control normal tissues, (V) are 0.86 to 0.90 from non-cancer patients. In carcinomatous tissues (Vc), there is an increase from 1.53 to 3.14, but in the corresponding surrounding non-cancer tissues (Vn) these show a decrease from 2.20 to 0.22 for SBR I, SNR II to SBR III. The ratio between (Vc) and (Vn) are found, according to carcinomatous aggressiveness, as 1.45 to 1.54, 1.69, 2.35 to 2.86 and 4.82 to 10.38 respectively for SBR I, lobular carcinoma, SBR II and SBR III; while the ratio is 1.04 for the normal tissue which come from non-cancer patients. The above results suggest the possibility of assessing the carcinomatous aggressiveness by radiorespirometry before a histopathological diagnosis, even in a lower aggressiveness as in SBR I cases which are difficult to diagnose and manage.

Genetic polymorphism and Parkinson's disease in Taiwan: study of debrisoquine 4-hydroxylase (CYP2D6)

Debrisoquine 4-hydroxylase (CYP2D6) is one of the cytochrome P450 enzyme families that catalyze the breakdown of a variety of exogenous and endogenous compounds. Previous reports have suggested that genetic polymorphisms of debrisoquine 4-hydroxylase are associated with susceptibility to Parkinson's disease (PD) in Caucasians. To determine if CYP2D6 also confers susceptibility to PD in Chinese patients, we carried out a study of genetic association using three polymorphic markers of the CYP2D6 gene, 188C/T, 1934G/A (mutant B), and 4268G/C. No differences of allele or genotype frequencies of these three polymorphisms were detected upon comparison of primary PD patients (n=53) with normal controls (n=94). The 1934A allele (mutant B), which accounts for the majority of poor metabolizers in Caucasians, is extremely rare in Chinese. Our data do not support the suggestion that the CYP2D6 gene is related to PD susceptibility in Chinese.

[Discussion on the elimination of measles based on the 45-year-incidence data in Inner Mongolia]

Measles incidence data collected since 1950 in Inner Mongolia is analyzed in this paper. The following characteristics have been noticed after measles vaccine was widely used: (1) the incidence and the mortality of measles kept decreasing, (2) The epidemic still occasionally appeared at low incidence level; (3) the proportion of cases in older children increased; (4) the peak month of the disease occurrence postponed; (5) the differences of incidence among districts depending on the implementation of vaccine and immunization. Since the goal of poliomyolitis eradication is given priority to and should be achieved, measles eradication program should not be overemphasized.

Effectiveness of low-dose ASA in prevention of secondary ischemic stroke, the ASA Study Group in Taiwan

This randomized double-blind controlled study was carried out to investigate the effect of 100 mg acetylsalicylic acid (ASA) per day on the secondary prevention of ischemic stroke. Patients who suffered a first ischemic stroke from 13 participating hospitals were enrolled. They were independent or only partially dependent in activities of daily living and all had received brain CT for diagnosis. Eligible patients were randomly allocated to the 100 mg ASA or the nicametate citrate (a vasodilator) groups, and trial medications were started within three to six weeks after the onset of stroke. The primary end point was cerebral reinfarction, and intracranial hemorrhage was classified as an adverse event. Four hundred and sixty-six patients participated in this study; and 222 cases (136 males and 86 females) were allocated to the ASA group while 244 cases (150 males and 94 females) were assigned to the nicametate group. No significant difference in baseline characteristics between the two groups was observed. Cerebral reinfarction developed 6.3% (14/222) in the ASA group and 11.9% (29/244) in the nicametate group. According to the Cox's proportional hazards model, the estimated risk ratio (ASA group vs. nicametate group) was 0.538, with a 95% confidence interval of 0.284-1.019. The result was of borderline statistical significance. The risk for cerebral reinfarction was reduced by almost 50% among those who took 100 mg ASA versus those who took nicametate.

[Analysis on poliomyelitis cases in Inner Mongolia in 1990-1993]

Out of 97 AFP cases, 68 were confirmed polio in Inner Mongolia in 1990-1993, in which 44.12% were diagnosed according to laboratory results. In this period, 13 strains of polio virus were isolated and identified from the stool samples of 62 AFP cases. The etiological results suggested that there was no dominant strain of polio virus in the whole region. Serological results showed that the positive rates of IgM antibody against polio virus were 75%, 26% and 0% in 1990, 1991, 1993 respectively which seemed to have a declining trend.

Multiobject recognition in a multichannel joint-transform correlator

A multichannel joint-transform correlator that incorporates a Dammann grating as a beam splitter is described. The Dammann grating splits a single incident beam into a two-dimensional array of equal-intensity beams, which form several channels for correlation. Each channel contains both a single target and a single reference. Optical experimental results are presented.

Relationship between periventricular lucencies on computed tomographic scans and vascular dementia

We evaluated 48 consecutive patients with periventricular lucencies (PVL) on CT scan of brain to determine the clinical significance of this finding. Twenty-one (43.7%) patients were demented; 27 (56.3%) patients had no dementia but had various other diseases. PVL were frequently associated with hypertension and previous stroke. We used a PVL scoring system to evaluate the degree of PVL. When the score was greater than 3.5, the sensitivity and specificity in separating vascular dementia from other diseases with PVL were 78% and 67% respectively (Kappa = 0.42). We conclude that although mild PVL may be a frequent but non-specific finding in patients with hypertension or previous stroke, moderate and severe PVL should raise the possibility of vascular dementia.

Levo-praziquantel versus praziquantel in experimental and clinical treatment of schistosomiasis japonica

Levo-praziquantel is the left isomer of racemic praziquantel. Animal experiments showed that it is an active component of schistosomicidal activity, while dextro-praziquantel is almost ineffective. Clinical trials in three endemic areas of Schistosomiasis japonica indicated that the therapeutic efficacy of levo-praziquantel is superior to racemic praziquantel. Pharmacokinetic and pharmacodynamic activities of the stereoselectivity of praziquantel isomers (enantiomers) are discussed.

Evaluation of 110 consecutive patients with dementias: a prospective study

We prospectively investigated 131 consecutive cases (both in- and outpatients) of suspected dementia to evaluate the relative frequency of different types of dementia in Chinese patients. Dementia was confirmed in 110 cases (84.0%). In contrast to the Western series, vascular dementia (39.1%) was slightly more frequent than the Alzheimer's disease (36.4%). Twelve cases (10.9%) of potentially treatable dementia were found. Careful clinical observation was the most useful part of the evaluation. CT scan of brain was the most useful laboratory test.

Impact of demented patients on their family members and care-givers in Taiwan

A standardized questionnaire was sent to family members or care-givers of 105 patients with dementia; 68 were returned. Eighty-eight percent of the patients were cared for at home by their spouses or adult children. The adverse impacts of dementia on patient family's economy, relations among family members, and social life are recognized. The majority of the subjects had only limited understanding of dementia. Having medical insurance helps the family in caring for the demented patients, emotionally and socially, but not financially. A better social welfare system, as well as health insurance, is recommended.

Spinal cord proliferative sparganosis in Taiwan: a case report

A 43-year-old woman suffered from low back pain and bilateral footdrop. A cisternal myelogram unexpected revealed multiple filing defects in the spinal canal extending from the lower cervical region to the caudal equina. Diagnostic exploration revealed numerous cystic organisms adhering to the spinal cord and nerve roots. Histopathological examination showed these organisms to be proliferative sparganum cestode larvae. Although these cestode larval infections have been reported a dozen times in humans from various parts of the world, this is probably the first reported case of spinal cord infection.