Persistence of detectable insecticidal proteins from Bacillus thuringiensis (Cry) and toxicity after adsorption on contrasting soils.

Insecticidal Cry, or Bt, proteins are produced by the soil-endemic bacterium, Bacillus thuringiensis and some genetically modified crops. Their environmental fate depends on interactions with soil. Little is known about the toxicity of adsorbed proteins and the change in toxicity over time. We incubated Cry1Ac and Cry2A in contrasting soils subjected to different treatments to inhibit microbial activity. The toxin was chemically extracted and immunoassayed. Manduca sexta was the target insect for biotests. Extractable toxin decreased during incubation for up to four weeks. Toxicity of Cry1Ac was maintained in the adsorbed state, but lost after 2 weeks incubation at 25 °C. The decline in extractable protein and toxicity were much slower at 4 °C with no significant effect of soil sterilization. The major driving force for decline may be time-dependent fixation of adsorbed protein, leading to a decrease in the extraction yield in vitro, paralleled by decreasing solubilisation in the larval gut.

[Intracranial aneurysm in Taiwan].

We reviewed the epidemiologic and clinical features of ruptured intracranial aneurysms based on the available data in the literature reported in Taiwan. Among 28,763 stroke patients registered by members of the Neurological Society of Taiwan, 600 patients had verified intracranial aneurysms (2.1%), constituting only 34.7% of 1,730 patients with subarachnoid hemorrhage. The male to female ratio was 0.68.1. The mean age was 54.6 +/ 14.3 years in men, and 56.5 +/ 13.8 years in women. Among the 409 patients whose aneurysmal sites were recorded, the aneurysm occurred at the anterior communicating artery in 109 (26.7%), at the posterior communicating artery in 90 (22.0%), at the internal carotid artery in 82 (20.1%), at the middle cerebral artery in 80 (19.6%), at the anterior cerebral artery in 50 (12.2%), at the vertebral-basilar system in 13 (3.2%), and multiple sites in 33 (8.1%). Cerebral angiography was performed in 72.2% of patients and operation was undergone in 57.7%. A randomized follow-up study in 59 patients showed survival rates of 63% for 1 month, 53.3% for 6 months and 43.6% for 1 year. The reported surgical mortality rates ranged from 7.7% to 12.5%. Prognosis was related to the score on the World Federation of Neurological Societies Subarachnoid Hemorrhage Scale. In Taiwan, the number of patients with intracranial aneurysm has been underestimated among who have presented with subarachnoid hemorrhage. The high mortality and morbidity of aneurysm rupture justify an aggressive attempt to establish a prompt and accurate diagnosis.

Prognosis of deeply comatose patients on ventilators.

Although the concept of brain death has been widely accepted, the criteria required for making the diagnosis remain controversial. This prospective study was undertaken to examine the reliability of a set of clinical criteria adopted in Taiwan. One hundred and forty deeply comatose patients (101 men, 39 women; mean age 49.5 (SD 17.6) years) requiring ventilation were studied. Seventy three patients met the clinical criteria for brainstem death; all developed cardiac asystole (97% within seven days) despite continued full cardiorespiratory support. Brainstem death was diagnosed in only two of the 21 patients with hypoxic or ischaemic insults. This stresses the rarity of hypoxic or ischaemic encephalopathy as a cause of brainstem death. The results show that if strict attention is paid to preconditions and exclusions, brainstem death can be reliably diagnosed on clinical grounds alone.

Stroke incidence in Ilan, Taiwan.

The purpose of this community hospital-based study of stroke was to assess the incidence rate of cerebral infarct, cerebral hemorrhage, and subarachnoid hemorrhage in a well-defined region of South Ilan. A prospective stroke registry was established at the two regional general hospitals serving about 184,000 inhabitants. From January to December 1991, a total of 258 stroke events were registered. Computed tomography was done in 99% of the stroke cases. The mean age for first-ever stroke in the region was 66.1 +/- 12.2 years. The annual incidence rates per 1,000 population for first-ever cerebral infarct in the respective age groups were 0.75 (45-54 years), 1.59 (55-64 years), 5.24 (65-74 years) and 8.01 (> or = 75 years). The incidence rates per 1,000 population for first-ever cerebral hemorrhage in the respective age groups were 0.52 (45-54 years), 1.19 (55-64 years), 1.05 (65-74 years) and 2.91 (> or = 75 years). The incidence rates per 1,000 population for first-ever subarachnoid hemorrhage in the respective age groups were 0.17 (45-54 years), 0.20 (55-64 years), 0.12 (65-74 years) and 1.21 (> or = 75 years). The age-specific incidence rate for first-ever stroke in the group aged 45 to 54 years observed in this study is higher than that in Western countries. The age-adjusted incidence rate for cerebral hemorrhage is significantly higher than that in Caucasians and is similar to that reported in Japan from 1974 to 1983.

[Moyamoya disease in Taiwan].

From January 1978 to December 1993, 73 patients with moyamoya disease were collected from seven neurological centers in Taiwan. The annual incidence of this disease in Taiwan is 0.024 per 100,000 population. There were 33 males and 40 females. The ages ranged from 2 to 62 years with a peak incidence in the 31 to 40 year age group (18 cases). Cerebral infarction occurred in 16 out of 19 juvenile patients (84.2%); by contrast, only 19 out of 54 adult patients (35.2%) presented with infarction. Hemorrhagic strokes were more frequent in adult patients. Computed tomographic scans following stroke showed cerebral infarction in 35 cases, ventricular hemorrhage in 21 cases, intracerebral hemorrhage in 11 cases and pure subarachnoidal hemorrhage in 6 cases. The most frequent initial symptom was motor disturbance (58.9%), followed by headaches (49.3%), and impaired consciousness (34.2%). Compared with reports from Japan, this survey showed a lower incidence of moyamoya disease in Taiwan.

[Unspecified subarachnoid hemorrhage in Taiwan].

We report the epidemiological and clinical features of unspecified subarachnoid hemorrhage by reviewing the literature published in Taiwan. Data from stroke registry from January 1988 to June 1992 showed that 4.9% of 23910 acute strokes were diagnosed as subarachnoid hemorrhage; in about half of them the cause of hemorrhage was not specified due to lack of confirmatory diagnostic examinations or to rapid deterioration of consciousness subsequent to bleeding that made angiography unapplicable during hospitalization. The age distribution, sex ratio, clinical profiles and associated risk factors in this group of patients were similar to those in the group of aneurysmal rupture. Therefore, the majority of patients categorized in the group of unspecified subarachnoid hemorrhage very likely had aneurysmal ruptures. The causes of subarachnoid hemorrhage were more frequently undetermined in hospitals where neuroradiological as well as neurosurgical facilities and staff were not immediately available, and also in patients whose clinical condition was poor on arrival at the hospital or who deteriorated rapidly after the onset. These two facts may partly explain the higher case-fatality rate and poorer prognosis in patients whose causes of subarachnoid hemorrhage were undetermined and effective surgical treatment could not be done.

Establishment and characterization of an HTLV-I cell line from a Taiwanese patient with HTLV-I-associated myelopathy.

We describe a Taiwanese woman with chronic progressive myelopathy, in whom Western blot analysis of the serum and cerebrospinal fluid (CSF) displayed positive reactions to human T-lymphotropic virus type I (HTLV-I) proteins, p19, p24, p28, p36, gp46 and p53. HTLV-I proviral genomes were detected in the peripheral blood mononuclear cells (PBMC) and CSF cells by nested polymerase chain reaction and Southern blot hybridization. HTLV-I was successfully isolated from PBMC stimulated with interleukin-2 (IL-2). The established cell line, named THAM-1, was an IL-2-independent T-cell line with CD2+, CD3+, CD4+, CD25+ and HLA-DR+. Retrovirus particles with type C morphology were observed in the THAM-1 cells by electron microscopy, and HTLV-I-related antigens were also demonstrated by immunocytochemical staining and Western blot assay. Southern blot analysis revealed that HTLV-I proviral genomes were integrated into the THAM-1 cellular DNA. In Northern blot analysis, two extra-species of RNA were detected in addition to three typical viral transcripts. For the first time, an HTLV-I-producing T cell line was established from a patient with HTLV-I-associated myelopathy in Taiwan, an HTLV-I non-endemic area.

[Cerebral hemorrhage in Taiwan].

Stroke was the leading cause of death in Taiwan for 19 years (1963-1981). About 60% of the hospitalized patients dying of stroke suffered from cerebral hemorrhage (CH). This fact denotes an important role of CH in causing fatal stroke. The widely use of computed tomography (CT) in Taiwan in the past decade enables clear differentiation between CH and cerebral infarction (CI). In Taiwan, the ratio of CH: CI is 1:1.5, which is 3.5 times higher than that of the Western countries. CH is most prevalent between aged 55 and 65 years; the male to female ratio after adjusted to that of general population is around 1.1:1. Hypertension is the most important risk factor (86.7%) and spontaneous CH is, therefore, often referred to as "hypertensive CH". CH has a predilection to occur in the putamen (41%), thalamus (23%), putaminothalamus (9.7%), subcortical white mater (9.3%), brainstem (6.5%), and cerebellum (5.9%). Motor dysfunction (80%) is the most frequent clinical manifestation, followed by disturbance of consciousness (50%), and language problems (31.1%). In addition to motor and consciousness disturbance, vomiting (30.8%) and headache (27%) are among important initial presentations, especially for cerebellar and intraventricular hemorrhage. For patients with stable condition after CH, medical treatment is the mainstay of therapy. If condition deteriorates during medical treatment, surgical intervention may be considered for patients with cerebellar, lobar, or putaminal hemorrhage. In Taiwan, 11.6% of patients with CH receive surgical treatment. The mortality rate one month after CH was 53.7% before the CT era; it has decreased to 23.3% in recent years.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cerebrovascular disease in the Taiwan area: past, present and future].

Before the end of the World War II, both hypertension and stroke were found to be less frequent among Taiwanese and little attention was paid to cerebrovascular disease (CVD). Since the late 1950s, the rising population of the aged in Taiwan, resulting from improved medical facilities and health care, have largely accounted for the increased number of CVD deaths. From 1957 to 1977, the tempo of increase in CVD deaths paralleled that in the elderly population. From 1963 to 1981, CVD was the leading cause of death. Community-based stroke registry surveys revealed the higher annual incidence, death rate and prevalence rate of stroke in our population than in Japan or western communities. Since 1981, active participation of neurologists and the availability of computed tomography (CT) in Taiwan, have created a new era in the management of stroke patients. Data from three teaching hospitals in Taipei and from 26 hospitals in Taiwan showed about 35% of acute strokes were diagnosed as cerebral hemorrhage (CH) by CT. Deaths from CH comprised 60% to 70% of the total stroke deaths, and hypertensive was the most important risk factor for both CH and cerebral infarct (CI). With improvement of medical facilities and increasing awareness of CVD, the mortality rate for CH dropped from 53.7% in 1978 to 33.3% in 1981, and further to about 25% in 1985. The effective anti-hypertension campaign started in 1986 has contributed to further reduction of the incidence and fatality of stroke.(ABSTRACT TRUNCATED AT 250 WORDS)

[Epidemiological study of cerebrovascular disease in the Taiwan area: current status].

We reviewed the reported epidemiological studies on cerebrovascular disease in the Taiwan area and discussed the following advantages and drawbacks of different approaches to data acquisition and analysis of the results. 1) Analysis of the data from vital statistics is readily available, and gives adequate information for secular trends, but the reliability of death certificate and the accuracy of subtypes of cerebrovascular disease must be taken into consideration. 2) A series of patients based on hospital registration can provide detailed data about the clinical manifestation and subtypes of stroke; whereas selection bias among hospitals may distort some clinical profile, and patients who have not visited the hospital are not included. 3) A community survey can obtain representative distribution of diseases in a community, but it takes much manpower and cost. The diagnosis of stroke is not very reliable because of limited usage of computed tomography and insufficient participation by qualified neurologists. 4) A community based hospital study has the advantage of combining a hospital registry and a community survey. It is difficult to conduct this type of study in the current medical environment in Taiwan since the referral system has not been well established. 5) A study of the survivalship of stroke can provide valuable information about the natural course of cerebrovascular disease.

Changes in mortality from cerebrovascular disease and clinical pattern of stroke in Taiwan.

The total population in Taiwan increased at a rate of about 20% per five-year interval during the period from 1957 to 1972 and has continued to increase at about 15% in the subsequent five-year periods. The number of cerebrovascular disease (CVD) deaths increased rapidly during the period from 1962 to 1982 and has tended to level off since 1982. From 1962 to 1977, the rate of increase in CVD deaths among the elderly almost paralleled the growth in the elderly population, but it has slowed in recent years. The age-adjusted CVD death rates are consistently higher in men than in women. In both sexes, the highest CVD death rates were reached in 1972, and a decreasing trend has been conspicuous since 1977. The age-specific death rates have shown a similar tendency in all age groups for both sexes, except for men aged 45 to 54 years. The cumulative mortality rates are higher for men than for women in all age groups over 55 years. Although cerebral hemorrhage (CH) constitutes 35.5% (Taiwan series) and 35.2% (Taipei series) of acute strokes, it comprises 60.1% (Taiwan series) and 57.7% (Taipei series) of all fatal strokes. The case-fatality rate for CH is three to four times that for cerebral infarct (CI). Hypertension is the most significant risk factor for almost all major types of stroke, being most frequently seen among patients with CH. Diabetes mellitus, cardiac disease and hyperlipidemia are more frequent in CI than in CH and subarachnoid hemorrhage (SAH). The low CI to CH ratio clearly indicates the high incidence of CH in Taiwan. The more rapidly declining death rate from CVD since 1982 is largely due to a reduction in the case-fatality rate for CH. The ratio of CI to CH has gradually been increasing since 1983, indicating a relative increase in the incidence of CI. The effective anti-hypertension campaign started in 1986 has contributed to the reduction in the incidence and fatality of stroke.

Geographic variations in Wilson's disease.

Certain features of Wilson's disease (WD) in Asia have been found to be different from those in other continents. The higher prevalence rate in Japan is presumably due to a higher consanguinity rate. In Chinese there is a tight linkage between WD and two gene loci for esterase D and retinoblastoma in the long arm of chromosome 13. The high proportion of patients with hepatic presentation accounts for early onset of WD in the Japanese and Chinese series. Skeletal involvement, leg hyperpigmentation, dark complexion, amenorrhea, epileptic seizures, and cerebral white matter degeneration are relatively more common among WD patients in Asia. Excessive copper in the liver appears to have a protective effect against hepatocellular carcinoma and type B hepatitis. Electrophysiological studies suggest widespread functional disturbances of the CNS in WD. Side-effects from penicillamine are rather frequent and often lead to interruption of the therapy. Trien is found to be effective without adverse reactions. Oral zinc therapy may be a suitable alternative for long-term management of WD patients in developing Asian countries.

[Secular trends in mortality for cerebrovascular diseases in Taiwan (1959-1989)].

Cerebrovascular disease (CVD) is predominantly a disease of the elderly, and its morbidity effects increase with advancing age. In Taiwan, the increasing proportion of the elderly, as a result of medical progress and improved health care in the past 30 years, is largely responsible for the apparent increase in the number of CVD deaths. From 1963 to 1981, CVD was the leading cause of death. The crude mortality rate (CMR) and age-specific mortality rate (ASMR) of CVD by sex were derived from vital statistical data from 1959 to 1989 in Taiwan. The age-adjusted mortality rate (AAMR) using the standard world population of WHO and the cumulative mortality rate (CUMR) from birth to less than 80 years of age were calculated. Before 1983, the total number of CVD deaths had increased steadily for 30 years. In 1989, the CMR was 76.6/100,000 in men and 67.7/100,000 in women. The highest AAMR was 158.5/100,000 in 1973 for men and 130.2/100,000 in 1972 for women, and the lowest AAMR was 91.3/100,000 in 1989 for men and 81.1/100,000 in 1972 for women. The highest CUMR was 26.3% in 1968 for men and 20.8% in 1972 for women, and the lowest CUMR was 14.5% in 1989 for men and 13.6% in 1989 for women. The AAMR and CUMR for both sexes reached a maximum in 1972 and began to decline thereafter. The declines in AAMR and CUMR were averaging 2%/yr for both sexes after 1972 and were averaging 5%/yr for men and 4%/yr for women after 1983. This declining trend in CVD deaths in Taiwan began later and has been slower than similar trends in Japan and the U.S.

[Prognosis of comatose patients on ventilator: a prospective study of brain death].

The concept of brain death is widely accepted in most countries. However, there are differences in the criteria for the diagnosis of brain death. In Taiwan, the diagnostic criteria of brain death has just been established. These criteria require strict preconditions to be fulfilled, necessary exclusions to be made, and adequate time of observation to ensure the irremediability of the disease. Tests of brainstem reflexes and apnea are then performed and should be repeated at an interval of at least 4 hours to establish the diagnosis. This prospective study was undertaken in order to examine the reliability of the present criteria. A total of 79 comatose patients (57 males and 22 females) on the ventilator were collected. Their ages ranged from 2.3 to 89 years, with a mean of 46.3 +/- 20.3 years. The preconditions or exclusions were not fulfilled in 5 patients (3 with drug intoxication, 1 with septicemia, and 1 due to an unknown cause). Among them, 1 with alcohol intoxication recovered well. Of 16 patients with hypoxic/ischemic brain damage, brain death was diagnosed in only 2; in the remaining 14 patients, 6 became vegetative and 8 died from cardiac arrest. Fifty-eight patients sustained structural brain damage, and brain death was diagnosed in 50 of these patients. The most frequent cause of brain death was head injury (31 cases), followed by intracerebral hemorrhage (11 cases). Of the 52 patients fulfilling the criteria of brain death, all sustained cardiac asystole in a limited interval of time (96% in 7 days).(ABSTRACT TRUNCATED AT 250 WORDS)

Immunoglobulin allotypes in caucasian and Chinese myasthenia gravis: differences from Japanese patients.

The G2m(n) allotype was significantly increased in Chinese female and high autoantibody cases, and in caucasians with pure ocular myasthenia, or undetectable autoantibody. In contrast to the strong Glm(x) association reported in Japanese, no overall Gm haplotype, or Am or Km allotype association was found in 90 (Taiwan) Chinese and 181 caucasian myasthenia gravis patients.

Association of HLA-DRw9 with myasthenia gravis in Chinese.

HLA phenotypes were studied in 59 Chinese myasthenia gravis (MG) patients. Unfractionated peripheral blood mononuclear cells were used for typing of HLA-A, B and C, and B-enriched lymphocytes for HLA-DR. Seventy-nine healthy subjects were included as controls. When compared with healthy controls, the patients showed significant increases in HLA-Bw46 (47.5% versus 14%, chi 2 = 18.7, P less than 0.001), HLA-DRw9 (59.3% versus 11%, chi 2 = 35.7, P less than 0.001), while HLA-DR3 was decreased (3.4% versus 32.9%, chi 2 = 18.2, P less than 0.001). Further analysis showed that the primary association was with DRw9 and the increase in Bw46 was secondary to it. Both HLA-Bw46 and -DRw9 were increased in all subgroups except where the age of onset was greater than 40 years. Finally, the HLA-A2-Bw46-DRw9 combination was also significantly increased in patients (25.4% versus 5.1%, chi 2 = 11.5, P less than 0.001), especially in the subgroups of MG with age of onset of less than 10 and males with age of onset of less than 40 years.

An autopsy-proved case of AIDS in Taiwan.

The first case of AIDS positively identified in a non-foreigner in Taiwan was a 25-year-old unmarried male who had practiced homosexuality for ten years. The patient began to have abdominal pain accompanied with loose stools and weight loss in June 1985, followed by fever, cough, headache, dizziness, and loss of memory. Facial hyperpigmentation and extensive oroesophageal candidiasis were noted. Laboratory studies showed severe lymphopenia with a reversed T-helper to T-suppressor ratio, cutaneous anergy and polyclonal gammopathy. Human immunodeficiency virus (HIV) antibodies were positive by ELISA and Western blot, and the virus was isolated from the blood. At autopsy, disseminated cytomegalovirus infection, extensive CNS toxoplasmosis and early lesions of Kaposi's sarcoma were demonstrated. The detection of HIV in the adrenal medulla supports the consensus that the virus is neurotropic.