Biomedical subjects

C H Lin

Publications and source records attributed to C H Lin.

At least 217 records · Page 12Linked to original sources

PubMed1997

Dissection of glutathionylspermidine synthetase/amidase from Escherichia coli into autonomously folding and functional synthetase and amidase domains.

The bifunctional glutathionylspermidine synthetase/amidase from Escherichia coli catalyzes both the ATP-dependent formation of an amide bond between N1 of spermidine (N-(3-amino)propyl-1, 4-diaminobutane) and the glycine carboxylate of glutathione (gamma-Glu-Cys-Gly) and the opposing hydrolysis of this amide bond (Bollinger, J. M., Jr., Kwon, D. S., Huisman, G. W., Kolter, R., and Walsh, C. T. (1995) J. Biol. Chem. 270, 14031-14041). In our previous work describing its initial characterization, we proposed that the 619-amino acid (70 kDa) protein might possess separate amidase (N-terminal) and synthetase (C-terminal) domains. In the present study, we have confirmed this hypothesis by expression of independently folding and functional amidase and synthetase modules. A fragment containing the C-terminal 431 amino acids (50 kDa) has synthetase activity only, with steady-state kinetic parameters similar to the full-length protein. A fragment containing the N-terminal 225 amino acids (25 kDa) has amidase activity only and is significantly activated relative to the full-length protein for hydrolysis of glutathionylspermidine analogs. This observation suggests that the amidase activity in the full-length protein is negatively autoregulated. The amidase active site catalyzes hydrolysis of amide and ester derivatives of glutathione (e.g. glutathione ethyl ester and glutathione amide) but lacks activity toward acetylspermidine (N1 and N8) and acetylspermine (N1), indicating that glutathione provides the primary recognition determinants for glutathionylspermidine amide bond cleavage. No metal ion is required for the amidase activity. A tetrahedral phosphonate analogue of glutathionylspermidine, designed as a mimic of the proposed tetrahedral intermediate for either reaction, inhibits the synthetase activity (Ki approximately 10 microM) but does not inhibit the amidase activity.

Amide Synthases↗

PubMed1997

Early postnatal dexamethasone therapy may lessen lung inflammation in premature infants with respiratory distress syndrome on mechanical ventilation.

Early postnatal use of dexamethasone has recently been shown to be effective in improving the pulmonary status in premature infants with respiratory distress syndrome (RDS). To study the effect of dexamethasone on pulmonary inflammatory responses, we studied ten infants treated with dexamethasone and ten infants without this treatment. Serial tracheal aspirates were obtained for cell counts, neutrophil counts, total protein concentrations, and leukotriene B4 (LTB4) and 6-keto prostaglandin (PG)F(1 alpha) levels before and after starting the study. Infants in the dexamethasone-treated group required significantly lower mean airway pressures for ventilation and had lower PaCO2 values from day 3 to day 14 than infants in the control group, suggesting better pulmonary function. For infants in the dexamethasone group, the tracheal aspirates showed significantly lower cell and neutrophil counts, protein concentrations, and 6-keto-PGF(1 alpha) and LTB4 levels than in the control group. We conclude that early postnatal dexamethasone therapy may lessen lung inflammation and improve pulmonary function in infants with RDS.

6-Ketoprostaglandin F1 alpha↗

PubMed1997

The effect of the selective PAF antagonist CIS-19 on PAF- and antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity in guinea-pigs.

We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methyl-formamido)-1, 2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs. Administration of CIS-19 (0.5-5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 micrograms/kg, i.v.) or substance P (6.5 micrograms/kg, i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye, was dose-dependently inhibited by CIS-19 (0.5-5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but it did not affect histamine (30 micrograms/kg, i.v.)- or substance P (6.5 micrograms/kg, i.v.)-induced microvascular leakage at all airway levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels in actively sensitized guinea-pigs, CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays little or no role in early airway responses following antigen challenge.

Airway Resistance↗

PubMed1997

The acetylcholine releaser linopirdine increases parietal regional cerebral blood flow in Alzheimer's disease.

Centrally acting cholinergic drugs have been reported to increase regional cerebral blood flow (rCBF) as measured by single photon emission computed tomography (SPECT) in brain regions affected by Alzheimer's disease (AD). We studied the effects of the acetylcholine releaser linopirdine (LPD) on SPECT rCBF in patients with probable AD. Twenty-four AD patients (12 M, 12 F; mean age +/- SD = 68.9 +/- 8.2 years) and 13 healthy controls (8 M, 5 F; 68.4 +/- 8.0 years) participated. AD patients were scanned with 20 mCi of Tc99m-ECD at baseline and following 4 weeks of treatment with LPD 40 mg TID (n = 15) or placebo TID (n = 9) in a double-blind trial. Healthy subjects were scanned for comparison with baseline AD scans. Cortical/cerebellar rCBF ratios were derived for nine cortical structures. The combined parietal association cortex showed a 20.6% reduction in patients relative to controls. Patients treated with LPD showed an increase in parietal rCBF of 4.1 +/- 5.8%; whereas those treated with placebo showed a decrease of -2.0 +/- 7.4% (F = 5.13; df = 1, 22; P = 0.03). These data support the conclusion that rCBF abnormalities in AD are, in part, truly "functional" and can be selectively altered with pharmacological interventions. The parietal activation seen with LPD and other cholinergic AD drug therapies suggests the importance of measuring parietal lobe neuropsychological function in the course of evaluating these drugs.

Acetylcholine↗

PubMed1997

The correlation of depression with functional activity in Parkinson's disease.

We evaluated 109 Chinese patients with Parkinson's disease (PD) in three ways: using a standardized psychiatric interview for depression and anxiety, using standardized neurological evaluation for motor disability, and using cognitive assessment for cognitive impairment. Six of the 109 patients who had dementia and another two afflicted with organic delusional disorder were excluded from further analysis. The remaining 101 PD patients were divided into the following three groups according to the DSM-III-R criteria: major depressive disorder (n = 18), other depressive disorders (n = 25) including dysthymic disorder and depressive disorder not otherwise specified, and no depression (n = 58). The frequency of major depressive disorder of the 109 PD patients was 16.5%, and the frequency of major and other depressive disorders, taken together, was 42.2%. Using the percentage points measured on the Schwab & England Activities of Daily Living Scale as the dependent variable to fit a multivariate regression model, we found the lower score significantly correlated with the diagnosis of depressive disorder and higher score of the Hamilton Depression Rating Scale, in addition to motor disability and disease severity of PD. Given the high frequency of depression and the significant correlation between depression and performance in daily functional activites, we believe that an evaluation of PD patients for coexisting depression is necessary for a better therapeutic outcome.

Aged↗

PubMed1997

Congenital bilateral agenesis of diaphragm: report of a case.

UNLABELLED: Bilateral agenesis of the diaphragm is a rare, life-threatening malformation. Infants with this defect rarely survive to have surgical intervention. We report a 32-week premature female infant who was born to a 36-year-old mother via vaginal delivery. The pregnancy course was complicated by hypertension and polyhydramnios. Cytogenetic study showed a normal 46 XX female karyotype. She had cyanosis, respiratory distress and scaphoid abdomen at birth. A roentgenograph confirmed the diagnosis of diaphragmatic hernia. Surgery was performed at 21 h of age. Bilateral agenesis of diaphragm, herniation of abdominal organs and oesophagus and pulmonary hypoplasia were noted. Furthermore, stomach and spleen were adherent to the mediastinum and vertebrae. The patient developed hypotension and persistent hypoxaemia and expired at age of 26 h. Autopsy revealed bilateral agenesis of diaphragm, hypoplasia of lungs, and pancreas fibrosis with mild hypoplasia of islets of Langerhans. CONCLUSION: Bilateral agenesis of diaphragm associated with pancreas fibrosis is a rare entity, and its clinical significance needs further investigation.

Abnormalities, Multiple↗

PubMed1997

A study of the referral patterns of obstetric clinics and the performance of receiving neonatal intensive care units in Taiwan.

To study the referral patterns of obstetric clinics, and the performance of receiving intensive care units measured by the survival of transported neonates, transport records were collected prospectively between July, 1991 and June, 1992. Two hundred and fifty-four transported neonates born in 51 obstetric clinics (level I units) in Tainan City and County, in southern Taiwan, were enrolled in this study. Nineteen percent of the transported neonates were very low birthweight infants (< 1500 g). Nearly equal numbers of them were transported to eight district hospitals (level II units) and to a tertiary center (level III unit), but these infants were 1.5 times more likely to die in a level II unit than a level III unit. In addition, equal numbers of infants assisted by mechanical ventilators were transported to level II and III units, but these infants were three times more likely to die in a level II unit than a level III unit (P = 0.006). Seventy-seven percent of the normal birthweight infants (> or = 2500 g) were transported to level II units, and the mortality in this group was 12.3% compared with 0% in those transported to the level III unit. Approximately 56% of these normal birthweight infants in level II units died of severe birth asphyxia. The referral patterns of level 1 units had an unfavorable effect on the survival of neonates requiring mechanical ventilation. Enhancing the skills of the staff in level I units to recognize and stabilize such infants, elevating the capability of level II units in treating some of these cases, and increasing the hospital beds for level III care are necessary to increase their chance of survival.

Health Services Research↗

PubMed1997

Conantokin-T selectively antagonizes N-methyl-D-aspartate-evoked responses in rat hippocampal slice.

This study investigated the mode of action of conantokin-T, a 21 amino acid peptide toxin isolated from the venom of the fish-hunting cone snail Conus tulipa, on excitatory synaptic transmission in rat hippocampal slices using intracellular recording techniques. Superfusion of conantokin-T (1-500 nM) specifically and irreversibly decreased the pharmacologically isolated N-methyl-D-aspartate receptor (NMDA)-mediated excitatory postsynaptic potential (EPSPNMDA) in a concentration-dependent manner but had no effect on normal excitatory synaptic transmission (EPSP). The sensitivity of postsynaptic neurons to NMDA but not to alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid was also antagonized by conantokin-T pretreatment. In addition, the conantokin-T-induced depression of EPSPNMDA could be antagonized by prior treatment of hippocampal slices with either DL-2-amino-5-phosphonovaleate (10 microM) or ifenprodil (20 microM). However, 7-chlorokynurenic acid (1 microM) had no effect on the action of conantokin-T. These findings indicated that conantokin-T modulates the NMDA receptor by an interaction with its glutamate binding site and polyamine recognition site.

Animals↗

PubMed1997

Swallowing difficulty in Parkinson's disease.

Dysphagia is a frequent and potentially serious complication of Parkinson's disease (PD). We examined the oropharyngeal swallowing ability in 19 PD patients (15 men and 4 women, mean age 68.42 years, mean Hoehn and Yahr stage 1.8) using modified barium swallow before and after administering oral levodopa (in combination with benserazide). Twelve (63.2%) patients demonstrated objective evidence of swallowing abnormalities; although only six patients (31.6%) had subjective complaints. Vallecula sinus and pyriform sinus residues were the most frequent abnormalities (47.4% and 42.1%); followed by delayed swallowing reflex (26.3%). Three patients demonstrated silent aspiration. In the 12 patients with abnormal swallowing, six (50%) showed objective improvement after levodopa treatment, while the remaining six showed no change. Of the former group of six, one patient showed improvement in the oral phase, but deterioration in the pharyngeal phase. We concluded that PD patients had a high percentage of objective swallowing abnormalities which could be reduced in half of the patients through the administration of levodopa treatment.

Adult↗

PubMed1997

Structural basis of DNA folding and recognition in an AMP-DNA aptamer complex: distinct architectures but common recognition motifs for DNA and RNA aptamers complexed to AMP.

BACKGROUND: Structural studies by nuclear magnetic resonance (NMR) of RNA and DNA aptamer complexes identified through in vitro selection and amplification have provided a wealth of information on RNA and DNA tertiary structure and molecular recognition in solution. The RNA and DNA aptamers that target ATP (and AMP) with micromolar affinity exhibit distinct binding site sequences and secondary structures. We report below on the tertiary structure of the AMP-DNA aptamer complex in solution and compare it with the previously reported tertiary structure of the AMP-RNA aptamer complex in solution. RESULTS: The solution structure of the AMP-DNA aptamer complex shows, surprisingly, that two AMP molecules are intercalated at adjacent sites within a rectangular widened minor groove. Complex formation involves adaptive binding where the asymmetric internal bubble of the free DNA aptamer zippers up through formation of a continuous six-base mismatch segment which includes a pair of adjacent three-base platforms. The AMP molecules pair through their Watson-Crick edges with the minor groove edges of guanine residues. These recognition G.A mismatches are flanked by sheared G.A and reversed Hoogsteen G.G mismatch pairs. CONCLUSIONS: The AMP-DNA aptamer and AMP-RNA aptamer complexes have distinct tertiary structures and binding stoichiometries. Nevertheless, both complexes have similar structural features and recognition alignments in their binding pockets. Specifically, AMP targets both DNA and RNA aptamers by intercalating between purine bases and through identical G.A mismatch formation. The recognition G.A mismatch stacks with a reversed Hoogsteen G.G mismatch in one direction and with an adenine base in the other direction in both complexes. It is striking that DNA and RNA aptamers selected independently from libraries of 10(14) molecules in each case utilize identical mismatch alignments for molecular recognition with micromolar affinity within binding-site pockets containing common structural elements.

Adenosine Monophosphate↗

PubMed1997

Aldehyde and phosphinate analogs of glutathione and glutathionylspermidine: potent, selective binding inhibitors of the E. coli bifunctional glutathionylspermidine synthetase/amidase.

INTRODUCTION: The tripeptide glutathione is converted to glutathionylspermidine (Gsp) in Escherichia coli and in trypanosomatid parasites by an ATP-cleaving Gsp synthetase activity. In parasites, an additional glutathionylation forms bis-(glutathionyl)-spermidine, trypanothione, believed to be the major surveillance thiol involved in oxidant defense mechanisms in trypanosomatid parasites. In E. coli, the Gsp synthetase is part of a bifunctional enzyme opposed by the hydrolytic Gsp amidase. RESULTS: Gsp amidase and Gsp synthetase activities of the bifunctional E. coli enzyme can be separately targeted by potent, selective slow-binding inhibitors that induce time-dependent inhibition. The inhibitor gamma-Glu-Ala-Gly.CHO most probably captures Cys59 and accumulates as the tetrahedral adduct in the amidase active site. Inhibitory Gsp phosphinate analogs are phosphorylated by ATP to yield phosphinophosphate analogs in the synthetase active site. Binding of phosphinophosphate in the Gsp synthetase active site potentiates the inhibition affinity for the aldehyde at the Gsp amidase active site by two orders of magnitude. CONCLUSIONS: Time-dependent inhibition of the Gsp amidase activity by the aldehyde substrate analog supports previous work that suggests glutathionyl acyl-enzyme intermediate formation in the Gsp amidase reaction mechanism. Use of potent selective inhibitors against Gsp amidase (aldehyde) and Gsp synthetase (phosphinate) activities provides further evidence of interdomain communication in the bifunctional enzyme from E. coli.

Aldehydes↗

PubMed1997

Depressive disorders among older residents in a Chinese rural community.

BACKGROUND: Two recent surveys of depression among Chinese elderly people sampled different populations, used different case ascertainment methods and resulted in a seven-fold difference in prevalence rates. The present study was conducted to compare prevalence rates obtained with two commonly used methods in the same population, and to examine the risk factors for depression. METHODS: The target population included all residents aged 65 years and over in a rural Chinese community. Participants were interviewed for demographic and medical information, examined by a neurologist and administered Chinese versions of the Geriatric Depression Scale-Short Form (GDS-S), the Cognitive Abilities Screening Instrument (CASI) and an Activities of Daily Living (ADL) form. Individuals who screened positive on the GDS-S were also interviewed by a psychiatrist for diagnosis according to the DSM-III-R criteria. RESULTS: Among the 1313 participants, 26% screened positive on the GDS-S and 13% were diagnosed as having a depressive disorder, including 6.1% with major depression. Individuals with depressive disorders were more likely to have poor ADL scores, lower CASI scores, and chronic physical illnesses. They were also more likely to be female, older, illiterate and without a spouse, but adding these variables did not increase the overall association with the GDS-S score. CONCLUSIONS: Depression was quite common in this Chinese rural geriatric population. The prevalence rate was twice as high when judged by depression symptomatology rather than clinical diagnosis. The critical risk factors were functional impairments, poor cognitive abilities and the presence of chronic physical illnesses.

Activities of Daily Living↗

PubMed1997

Reversed arterial flow in free flap surgery for leg reconstruction.

A lower leg open fracture with an accompanying extensive soft-tissue defect may require free flap transfer to resurface the wound. In open-leg fracture injuries the major arteries are frequently damaged during the injurious event. When the antegrade arterial blood flow is not available for arterial inflow to the free flap, end-to-side arterial anastomoses or a venous graft from a proximal healthy artery is an appropriate solution. Reversed arterial flow is another technique that may be used to provide arterial inflow to the free flap. We report 5 patients with open tibial fracture injuries that were successfully covered using latissimus dorsi muscle free flaps with reverse arterial inflow and either antegrade venous outflow (4 patients) or retrograde outflow (1 patient). This technique is indicated when (1) the defect is not located at the site adjacent to the residual antegrade artery, (2) a long vein graft might pass through severely scarred soft tissue, or (3) after failure in end-to-side anastomosis with accompanying insufficient antegrade proximal arterial flow but good distal arterial reflux.

Adolescent↗

PubMed1997

Effect of thyroxine on pancreatic digestive enzymes and ornithine decarboxylase gene expression in neonatal rats.

BACKGROUND: Thyroxine has been shown to play a role in the development of exocrine pancreatic enzymes in neonatal rats. METHODS: To further evaluate the regulatory mechanisms for thyroxine in pancreatic development, we examined the changes in the expression of pancreatic enzymes (amylase and trypsinogen) and ornithine decarboxylase (ODC) genes following daily injection of thyroxine for 5 and 10 days to neonatal rats (5 days old). RESULTS: Total pancreatic proteins and DNA contents as well as the activity of ODC and exocrine enzymes were significantly increased after 5 and 10 days of thyroxine treatment. These increases were associated with parallel alterations (to three to fourfold rise) in steady-state mRNA levels of both amylase and trypsinogen. In contrast, thyroxine only produced a 57-68% increase in steady-state ODC mRNA levels. CONCLUSIONS: These data suggest that thyroxine stimulated the express of amylase and trypsinogen genes partly due to increased transcriptional rate and/ or decreased mRNA turnover. Thyroxine also stimulated ODC gene expression. However, the stimulatory mechanisms may involve transnational or posttranslational regulation of ODC and are independent of thyroxine effects.

Amylases↗

PubMed1997

The functional outcome of lower-extremity fractures with vascular injury.

Salvage of lower-extremity Gustilo type IIIC fractures is difficult, time-consuming for the patients and physicians, and not universally successful because of poor functional outcomes. Even if successful with limb salvage, the functional result may be unsatisfactory because of mutilating injuries to muscle and nerve, bone loss, and the presence of chronic infection. From July 1991 until July 1994, revascularizations of open IIIC fractures were attempted for wounds with Mangled Extremity Severity Score (MESS) < or = 10. The functional results were evaluated at 2 years after injury. Thirty-six lower-extremity revascularizations were performed on 34 patients, including 1 patient with bilateral distal tibial IIIC fractures and a child with IIIC femoral fracture accompanied by ipsilateral distal tibial amputation. Excluded were patients with below-ankle IIIC fractures as well as patients who underwent immediate amputation at admission. After the revascularization, seven patients with IIIC fractures (7 of 36, 19.4%) underwent secondary amputation within 1 week. At the 2-year follow-up, the overall secondary amputation rate was 25% (9 of 36) and the salvage rate was 75% (27 of 36). Those were no deaths. Of the 29 salvaged limbs among these 27 patients, 23 limbs (23 of 29, 79.3%) required secondary coverage procedures that included 12 free flap transfers (12 of 29, 41.4%). Every patient needed subsequent reconstructive surgery to achieve an acceptable functional result. In this series, MESS was able to predict the secondary amputation rate and the functional result. Sixteen of the 17 limb-salvaged patients with MESS < or = 7 were able to achieve minimal functional requirements, whereas 3 of the 10 patients with MESS = 8 to 10 failed to achieve minimal functional requirements at the 2-year follow-up. Using statistical analysis, we found that the salvaged limbs with MESS < or = 9 exhibited a significant difference in achieving adequate function compared with limbs with MESS > 9. Using our protocol for treatment for IIIC fractures, the threshold for immediate amputation can be raised from MESS = 7 to MESS = 9. Our conclusions are (1) more severely injured limbs have poor functional results, (2) every patient needs subsequent reconstructive surgery, and (3) the MESS may be helpful in decision-making.

Adolescent↗

PubMed1997

Free fibula osteoseptocutaneous graft for reconstruction of segmental femoral shaft defects.

Seventeen major reconstructions of the femoral shaft using vascularized fibula osteoseptocutaneous grafts were performed from August 1984 to September 1993. Patients were 14 males and 3 females, with an average age of 34 years. All patients had sustained high-energy trauma in motor vehicle crashes and had bone defects averaging 10 cm. The skeletal defect was primary attributable to bone loss at the time of injury (2 cases) or secondary after infection and sequestrectomy (15 cases). Vascularized fibular transfer was performed at an average of 6 months after trauma. The fibular graft was inserted as a single strut in 10 cases and as a double-barrel composite in 7 cases. Patients were evaluated at an average of 43 months after surgery. All grafts eventually united, and no patient showed evidence of recurrent or persistent infection. The average time to radiologic union was 8 months, and the average time to full weight bearing was 14 months. Secondary bone grafting and internal fixation were required in five cases because of delayed union, stress fracture, or screw loosening. All cases of delayed union and stress fracture were in those reconstructed by single-strut fibular graft. Four cases (24%) required quadriceps plasty and arthrolysis. The final average arc of active knee motion was from 0 to 80 degrees. Limb length discrepancy ranged from 0 to 7 cm (average, 3 cm). Five cases (29%) had varus deformity averaging 30 degrees. The fibular graft hypertrophied to 100% of the femoral circumference in cases followed for 3 years. Donor site morbidity was negligible. At the time of final follow-up, 13 patients had returned to their original jobs, two were permanently disabled because of below-knee amputation, and two were retired. The study suggests that vascularized fibula osteoseptocutaneous transfer is a valuable procedure for reconstruction of large, previously infected femoral shaft defects.

Adolescent↗

PubMed1997

Metacarpal hand: classification and guidelines for microsurgical reconstruction with toe transfers.

Metacarpal hand refers to the hand that has lost its prehensile ability through amputation of all fingers with or without amputation of the thumb. Functional restoration can be achieved by a wide variety of microvascular toe transfer techniques. When deciding which procedure should be used, careful consideration must be given to the level of amputation of the fingers as well as the functional status of the remaining thumb. In this article we propose a classification for the various patterns of the metacarpal hand along with guidelines for selection of the proper toe transfer procedure.

Adult↗

PubMed1997

The Kinmen Neurological Disorders Survey (KINDS): a study of a Chinese population.

We conducted an epidemiological study of several neurological disorders among the Chinese aged 50 years or older on the islet of Kinmen. All participants were interviewed and examined by neurologists. From the targeted population of 5,061 individuals, 3,915 (77.4%) of them completed the evaluations. Among the 4,087 individuals with whom face-to-face contact was made, the refusal rate was 4.2%. The disorders of interest were dementia, Parkinson's disease, essential tremor, stroke, transient ischemic attacks, and migraine. Among the 3,915 participants, 366 cases were found with 1 or more of the surveyed neurological disorders on the prevalence day, August 1, 1993, yielding a prevalence of 93.5/1,000. The purpose of this study, the general methodology, and some overall findings are presented in this communication in order to provide a common background for detailed findings on each disorder to be reported separately.

Age Factors↗