Effects of phenytoin on the amygdala neurons in vitro

The present study was aimed at elucidating the possible mechanisms underlying the anticonvulsant efficacy of phenytoin using intracellular recording techniques in the in vitro amygdalar slice preparation. Synaptic response mediated by the N-methyl-D-aspartate (NMDA) receptor (EPSPNMDA) was isolated pharmacologically by application of a solution containing non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (10 mumol/l) and gamma-aminobutyric acidA receptor antagonist bicuculline (20 mumol/l). Phenytoin inhibits the amplitude of EPSPNMDA without affecting the postsynaptic depolarization induced by exogenous application of NMDA. In addition, phenytoin increases the magnitude of paired-pulse facilitation which is consistent with a presynaptic mode of action. These results suggest that inhibition of transmitter release due to presynaptic blockade of Na+ and/or Ca2+ channels may account largely for the anticonvulsant efficacy of phenytoin.

Use of two-stage test statistic in the two-period crossover trials

For two-period crossover trials where the residual carryover can only exist in the presence of treatment effect, Willan (1988, Biometrics 44, 211-218) recommended use of the maximum test statistic that chooses the analysis with the larger test statistic corresponding to the parallel analysis and the crossover analysis. We construct two alternative two-stage test procedures, based on Grizzle's approach, that maintain the actual type I error rate at the desirable level. The power, accuracy, and precision of the analysis based on the modified two-stage procedures are compared to those based on the parallel analysis, crossover analysis, and the maximum test statistic.

Unilateral pulmonary edema during general anesthesia--report of two cases

Unilateral presentation of pulmonary edema, though well known to occur, is an uncommon entity. Previous reviews of this subject have discussed the different etiologies, which include rapid reexpansion of collapsed lung, down lung syndrome (gravitational edema), systemic-to-pulmonary arterial shunts, heart failure, compression or occlusion of pulmonary vasculatures, obstruction of a bronchus and an acute manifestation of neuropulmonary reaction (neurogenic pulmonary edema). Occurrence of this complication during surgery, however, is even rarer. We report 2 cases of unilateral pulmonary edema occurring during general anesthesia for elective surgery.

Comprehensive gastric emptying study for type-II diabetes mellitus dyspeptic patients

BACKGROUND

Gastrointestinal symptoms without demonstrable lesions in the upper gastrointestinal tract are common in diabetic patients. Scintigraphic liquid- and solid-phase gastric emptying studies and gastric emptying of indigestible particles were performed to determine the gastric emptying function in type-II diabetes mellitus patients with dyspepsia.

METHODS

Twenty type-II diabetic patients with symptoms suggestive of delayed gastric emptying were included. A gelatin capsule containing 10 rod-shaped radiopaque markers was ingested, along with the solid-phase test meal, to assess the emptying of indigestible particles. Scintigraphic liquid-phase gastric emptying studies were performed on a separate day.

RESULTS

There were 7 patients (35%) with delayed liquid-phase gastric emptying, 14 patients (70%) with delayed solid-phase gastric emptying, and 14 patients (70%) with abnormal gastric emptying of indigestible particles. There were only three patients (15%) with normal gastric emptying of both the liquid and solid phase. Furthermore, only one patient showed normal result in all three gastric emptying studies.

CONCLUSIONS

For determining abnormalities in gastric emptying function for type-II diabetic dyspepsia patients, comprehensive gastric emptying studies, including scintigraphic liquid- and solid-phase gastric emptying studies and gastric emptying of indigestible particles, are most helpful.

Family history: a comprehensive genetic risk assessment method for the chronic conditions of adulthood

Targeting individuals with increased risk for common, chronic disease can improve the efficiency and efficacy of preventive efforts by improving the predictability of screening tests and participant compliance. Individuals with the greatest risk for these disorders are those with a genetic susceptibility. The purpose of this study was to determine the feasibility of using a single, comprehensive family history as a method for stratifying risk for many preventable, common genetic disorders. Family histories obtained in a prenatal diagnostic clinic were reviewed regarding cardiovascular diseases, diabetes and several cancers; 42.5% of individuals reported a family history for at least one of the disorders under study. Familial coronary artery disease was most commonly reported (29% of participants), followed by noninsulin-dependent diabetes (14%). Qualitative characterization of disease susceptibility was also accomplished using family history data. For example, occurrence of different cancers within pedigrees was suggestive of familial cancer syndromes, and clustering of noninsulin-dependent diabetes and cardiovascular disease suggested an insulin resistance syndrome. Depending on the specific disease, 5 to 15% of at-risk individuals had a moderately increased risk (2 to 5 times the population risk), and approximately 1 to 10% had a high risk (absolute risks approaching 50%). Family history reports of common, chronic disease are prevalent among the population at large, and collection and interpretation of comprehensive family history data is a feasible, initial method for risk stratification for many preventable, chronic conditions. These findings may have important implications for disease prevention and management.

Normal data for lumbar spine bone mineral content in healthy Chinese men

The aim of this study was to evaluate the influence of age on bone mineral density (BMD) of teh lumbar spine for health Chinese men. In 430 healthy Chinese men (ages 20-92 years) living on Taiwan, BMD at the level of the 2nd to 4th lumbar vertebraes (L2-L4) was determined with a commercial dual-energy X-ray absorptiometer (DXA). Our study found that the peak BMD value of lumbar spines of healthy Chinese men was 1.056 +/- 0.127 g/cm2 which occurs from age 20 to 29. The results show that a linear correlation between the age and BMD of lumbar vertebraes for healthy Chinese is notable. Only slight decreases of BMD values in the different age groups are found. In comparison with the normal data of white men and Asian men from Japan and Korea, the mean BMD values of lumbar spines of Chinese men seem to be lower than those of the white, Japanese, and Korean men of the same ages. Our findings indicate that the influence of age and ethnicity may exist in the BMD values for healthy Chinese males.

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.

Technetium-99m-tetrofosmin SPECT imaging of lung masses: a negative study

Technetium-99m-tetrofosmin has emerged as a new radiopharmaceutical for myocardial imaging, in competition with 201Tl and 99mTc-MIBI. In this study, 99mTc-tetrofosmin was evaluated for its ability to detect malignant and benign lesions from single solid lung masses.

METHODS

Forty-nine patients with a single solid lung mass based on chest radiograph findings received 99mTc-tetrofosmin SPECT of the chest to evaluate the value of 99mTc-tetrofosmin SPECT for detecting malignant and benign lesions.

RESULTS

Only 61% of the lung malignancies were detected by 99mTc-tetrofosmin SPECT of the chest, including 53% of epidermoid carcinoma (ca), 67% of adeno ca, 75% of small-cell ca, 0% of undifferentiated large-cell ca and 100% of other lung malignancies. In addition, 50% of the benign lesions were detected by chest 99mTc-tetrofosmin SPECT. The probability of tetrofosmin uptake in the mass was not related to mass size. The diagnostic sensitivity, specificity and accuracy were 61%, 50% and 59%, respectively, for differentiating malignant and benign lesions when diagnosing a single solid lung mass.

CONCLUSION

Technetium-99m-tetrofosmin SPECT of the chest is of little or no value for the detection of lung ca from single solid lung masses.

Prevalence of headaches in a Chinese elderly population in Kinmen: age and gender effect and cross-cultural comparisons

OBJECTIVE

To investigate the prevalence of headaches in a Chinese elderly population.

BACKGROUND

There are few headache surveys in the elderly. Previous studies have shown a low headache prevalence in Chinese.

METHODS

TARGET POPULATION

eligible registered residents > or = 65 years old (N = 2,003) in two townships of Kinmen Island on August 1, 1993. All participants completed a headache questionnaire and underwent clinical evaluation and examination by a neurologist. Headache diagnoses were made according to the International Headache Society, 1988.

RESULTS

1,533 persons (77%) participated in the study, of whom 584 (38%) had at least one episode of headache in the previous year. One-year prevalence of migraine was 3.0%, and tension-type headache, 35%. The prevalence of migraine, but not tension-type headaches, continued to decline with age in the elderly. Life-time prevalence of "incapacitating headache" was 10%, and that of migraine, 5.2%. Forty-two percent of migraineurs stopped having migraine before this survey. In comparison with "10 years ago" 8% participants felt their current headaches were worse, 25% better, and 67%, no change, with a net improvement of 17%.

CONCLUSIONS

We have reported the highest headache prevalence among different Chinese elderly populations, but these were still lower than those reported from Western series. More than half of the elderly life-time migraineurs still had attacks of migraine. Severe headaches, including migraine but not tension-type headaches, declined with age.

Treatment of a large segmental bone defect with allograft and autogenous bone marrow graft

Management of segmental bone defects is a challenge to orthopedic surgeons. We report a 23-year-old man who sustained segmental bone loss of 9 cm in length in his left femur due to an open fracture. Open reduction and internal fixation with a 95 degrees angle blade plate and screws, supplemented with a composite of two femoral head allografts and a graft of 100 mL of autogenous bone marrow, was performed 3 weeks after the injury, when the soft tissues had healed. The postoperative rehabilitation program included delayed weight bearing (crutches for 3 months), a limited early range of motion of the left knee, and quadriceps muscle exercise. Callus bridging was noted on x-ray films 3 months postoperatively. Clinical and radiographic union were noted 6 months after the surgery. We suggest that this new and simple method can be applied to successfully treat segmental bone loss of more than 6 cm in length.

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.

Technetium-99m-HMPAO brain SPECT in systemic lupus erythematosus with CNS involvement

Functional brain SPECT is playing an increasingly important role in evaluating CNS conditions in patients with systemic lupus erythematosus (SLE). However, SPECT findings varied in different studies because of their small population. Furthermore, earlier researchers, being restricted by the resolution of the camera, might not have been able to evaluate deep-seated nuclei such as the basal ganglia and thalamus. In this study, we describe the different patterns of SPECT findings in SLE patients with CNS involvement.

METHODS

Seventy-two SLE patients (aged 14-67 yr; mean 33.2 yr) were divided into three groups: Group 1 with definite neuro-psychiatric disorder (including stroke, seizures and psychosis); Group 2 with minor neuropsychiatric disorders (headache, dizziness and recent memory impairment); and Group 3 without any neuropsychiatric symptoms or signs. Ninety minutes after injection of 1110 MBq 99mTc-HMPAO, brain SPECT was performed using a dual-head camera and fan-beam collimator. In addition, MRI and an electroencephalography (EEG) were also performed.

RESULTS

SPECT findings were normal in 87% of the Group 3 patients and abnormal in all Group 1 patients; 84.6% of the Group 2 patients had abnormal SPECT findings. The parietal, frontal and temporal lobes were the most common areas of CNS involvement. Parietal lobes were involved in 95.6% of Group 1 patients and 80.7% in Group 2 patients. Frontal lobes were involved in 56.5% of Group 1 patients and 65.3% of Group 2 patients. Temporal lobes were involved in 56.5% of Group 1 patients and 46.1% of Group 2 patients. The basal ganglion was involved in about 30% of Group 1 patients and 11.5% of Group 2 patients, while the thalamus and cerebellum were less involved in neuropsychiatric SLE. MR images showed less sensitivity in the detection of CNS involvement than the SPECT and were normal in 27.3% of patients with definite neuropsychiatric disorders. The EEG and anticardiolipin antibody did not correlate well to the clinical diagnosis.

CONCLUSION

HMPAO brain SPECT had the best correlation with the clinical diagnosis and may provide additional and objective information on SLE patients with potential CNS involvement.

Rhenium-188 hydroxyethylidene diphosphonate: a new generator-produced radiotherapeutic drug of potential value for the treatment of bone metastases

The search for an ideal radioisotope for systemic radiotherapy continues. As a generator-produced radioisotope emitting both beta and gamma rays and having a short physical half-life of 16.9 h, rhenium-188 is a very good potential candidate for systemic radiotherapy. In this study, we labeled hydroxyethylidene diphosphonate (HEDP) with 188Re and analyzed the biodistribution and bone uptake following intravenous injection in rats to assess its potential for clinical use. The rats were injected with approximately 14.8 MBq (0.4 mCi) 188Re-HEDP in a volume of 0.1 ml intravenously and then sacrificed at 1 h, 24 h, or 48 h (four rats at each time). Samples (about 0.1 g) of lung, liver, kidney, spleen, testis, muscle, stool, and bone (thoracic vertebra) were taken and weighed carefully. In addition, a 1-ml sample of blood was drawn from the heart and 1 ml of urine was taken from the urinary bladder immediately after killing. Tissue concentrations were calculated and expressed as percent injected dose per gram or per milliliter (% ID/g or ml). Bone lesions were created in the right tibial bone in three rabbits to calculate the lesion to normal uptake ratio (L/N ratio). The biodistribution data showed that the radioactivity in the bone tissue was as high as 1.877% ID/g at 1 h and that it climbed to 2.017% ID/g at 4 h. The activity level in the kidney was highest at 1 h but declined rapidly throughout the study. The radioactivities in the lung, liver, muscle, spleen, testis, blood, and stool were all lower than 0.3% ID/g at 1 h and also declined rapidly. The biological half-life in bone was the longest (60.86 h). In contrast, the biological half-lives in muscle and blood were short (2.99 h and 6.21 h respectively). The concentrations of radioactivity in muscle, spleen, testis, and stool were quite low throughout the study. Most of the radiotracer was excreted by the urinary system. The L/N ratio was 4.23+/-0.21 in rabbits injected with 188Re-HEDP and 4.25+/-0.23 in those injected with technetium-99m methylene diphosphonate. In conclusion, we would suggest that 188Re-HEDP is a very good potential candidate for the treatment of bone metastases because of the following characteristics: (1) it is generator produced; (2) it has a short half-life; (3) it emits gamma rays suitable for imaging; (4) there is highly selective uptake in the skeletal system and bone lesions; and (5) it has a low non-target uptake and rapid clearance in nonosseous tissue.

Droperidol treatment of status migrainosus and refractory migraine

We conducted a pilot study of intravenous droperidol in 35 patients (32 women and 3 men; mean age 43 years) with status migrainosus (n = 25) or refractory migraine (n = 10) in an ambulatory infusion center. Headache was graded as severe in 21 patients and moderate in 14. An intravenous line was started and kept open. Droperidol (2.5 mg) was given intravenously every 30 minutes until either three doses were given or the patient was completely or almost headache-free prior to the next dose. Seven patients received one dose, 12 received two doses, and 16, three doses (mean 5.6 mg). Our success rate (headache-free or mild headache) was 88% (22 of 25) in patients with status migrainosus and 100% (10 of 10) in patients with refractory migraine. The average time to headache improvement was 40 minutes (n = 35), to mild headache--60 minutes (n = 32), and to headache-free--105 minutes (n = 28). Nausea, vomiting, and light and sound sensitivity resolved in all but 5 patients. Four patients had an asymptomatic systolic blood pressure drop > or = 20 mm Hg. Most patients were sedated (34 of 35). Five patients developed akathisia and 1 dystonia. At follow-up 24 hours after discharge, the recurrence rate (headache intensity from none or mild to moderate or severe) was 23% in status migrainosus and 10% in refractory migraine. Twenty-one patients were sedated, while 19 had extrapyramidal symptoms, mainly restlessness. Droperidol is effective and safe in treating status migrainosus or refractory migraine. Hypotension was uncommon. Patients should be warned of sedation and akathisia.

Large sample tests for binary outcomes in fixed-dose combination drug studies

Several test statistics are developed for testing the hypothesis that the combination of two drugs at a fixed-dose regimen is more effective than both of the single drugs used alone with respect to a dichotomous response variable. The response probability, logit, and arcsine-root scales are considered. The power function and the significance level are derived for large samples. For the sample size per group of 20 or greater, the power and type I error rate can be accurately calculated using the large sample power function when the response probability ranges from 0.2 to 0.8. These tests have similar power behaviors. In small samples, the large sample power functions of two of the tests can severely underestimate the type I error rate while overestimation can occur with one other test. The utilities of these tests are extended to unbalanced sample size cases. Generally speaking, there is a loss of power with unequal sample size allocation, but the loss is not severe.

Poststroke depression among the Chinese elderly in a rural community

BACKGROUND AND PURPOSE

A door-to-door survey was conducted in two townships in the Kinmen islets to investigate the prevalence and other characteristics related to depressive disorders of stroke survivors in an elderly Chinese population.

METHODS

Our target population comprised the registered residents > or = 65 years old (n = 2056) of a total population of 26 105 on August 1, 1993. All participants answered a questionnaire, filled in a Geriatric Depression Scale-short form (GDS-S), and received a neurological examination. Depression was defined as a GDS-S score > or = 5.

RESULTS

Twenty-eight of 45 stroke survivors (62.2%) and 491 of 1471 nonstroke subjects (33.4%) were classified as depressed. The frequency of stroke survivors' depressive disorders was significantly higher that of nonstroke subjects (P < .001). Multiple regression analysis indicated that GDS-S scores were most related with the activities of daily living (R2 = .19, P = .004) in the stroke survivors.

CONCLUSIONS

Depressed mood was common after stroke, and activities of daily living were an important factor for depression in stroke survivors in the community.

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.

Role of radioisotope penile plethysmography in the evaluation of penile hemodynamics in impotent patients

Nineteen impotent patients were included in the study. Radioisotope penile plethysmography using technetium-99m-labelled RBC was performed on each patient before and after intracavernosal injection of prostaglandin E1 (PGE1) for quantitating the penile hemodynamic change. The peak penile blood flow (PPF) and penile blood volume change (dPV) were evaluated. The results revealed that (a) the PPF values (mean 2.24 +/- 1.38 ml/min) of all patients were lower than that of the patients with no arterial changes previously reported, and (b) there was good correlation between PPF and dPV (r = 0.75). We conclude that quantitative radioisotope penile plethysmography coupled with intracavernosal injection of PGE1 is a valuable method for the objective evaluation of the penile erectile response of impotent patients, and that the PPF values of the impotent patients with arterial insufficiency might be a reliable parameter of penile volume change.

Correlation between patterns of antral contractility and gastric emptying of radiopaque markers

OBJECTIVES

Gastric clearance of radiopaque markers (ROMs) has been proposed as an easy and noninvasive technique for assessment of gastric emptying. This study was conducted to evaluate the role of antral obliterating contractions in gastric emptying of ROMs in healthy volunteers.

METHODS

Fifteen healthy volunteers, 12 males and three females, aged 21-38 yr, were enrolled in this study. Simultaneous recording of scintigraphic solid phase gastric emptying, gastric clearance of ROMs, and gastric manometry were performed after an overnight fast. The data of scintigraphic solid phase gastric emptying were expressed by half-emptying time (t1/2). The ROMs remaining in the stomach were counted fluoroscopically 2.5 and 4.5 h after the test meal. The time for the appearance of antral obliterating contractions after the meal was calculated.

RESULTS

Six subjects (40%) passed all 10 ROMs after 4.5 h of recording. Among these six subjects, five had antral obliterating contractions 190-251 min (mean 232.2 +/- 24.3 min) after the test meal. There was no significant difference in t1/2 between subjects with or without antral obliterating contractions within the 4.5 h of recording.

CONCLUSIONS

There was a considerable intersubject variation in the time of first antral obliterating contraction after the test meal. In the healthy volunteers, all ROMs were passed when there was a postprandial antral obliterating contraction. However, some of the ROMs still passed from the stomach in the absence of antral obliterating contractions.

Comparison of risk factors for lacunar infarcts and other stroke subtypes

BACKGROUND

Lacunar infarction (LI) is an ischemic stroke subtype with unique clinical, radiological and pathological features. Its relation to other stroke subtypes is unclear. To better understand the underlying pathological process of LI, we compared the risk factors of LI with those of other stroke subtypes.

METHODS

During the study period (from January 1, 1990 to December 31, 1991), 240 consecutive patients with first-ever strokes admitted to the stroke unit of our hospital were enrolled to the study and were classified into one of the four stroke subtypes (52 with LI, 80 atherothrombotic infarcts, 38 cardiogenic embolism and 70 brain hemorrhage) based on their computed tomography (CT) and clinical features using the guideline developed by the National Institute of Neurological Disorders. Eighty outpatients of similar age who had either low back pain or cervical spondylosis were recruited from the clinics of Neurology to serve as non-stroke controls. Data collected included demographics, lifestyle, and other vascular risk factors. Detailed physical and neurological examination, blood biochemistry and Doppler ultrasound on cervical vessels were performed.

RESULTS

Our investigations revealed that LI is a common stroke subtype accounting for 21% of all first-ever strokes in our hospital. Like ischemic stroke patients, those with LI were much more likely to have hypertension, diabetes, heart disease and carotid disease when compared with non-stroke controls. Patients with brain hemorrhage had less history of diabetes and lower levels of cholesterol than LI patients.

CONCLUSIONS

LI patients seemed to share more risk factors with ischemic stroke patients than with brain hemorrhage patients. These shared risk factors suggest a possibly similar underlying pathological process between ischemic strokes and LI patients. Careful screening for those risk factors should be part of the mandatory clinical management for the prevention of LI.