Age differences in remote pointing performance

The purpose of this study was to investigate age differences in remote pointing movements. The subjects were recruited from three age groups (ages 18-22 yr., 40-50 yr., and 60-70 yr., with 9 men and 9 women in each group). They were required to perform cursor-positioning tasks using a remote pointing device, in which the dependent measures were the time taken to reposition the cursor and the accuracy of subjects' movement trajectories. The movement time was further separated into two components, First Submovement duration and Adjustment Submovement duration. Analysis indicated that age groups showed reduced performance on remote pointing. Moreover, remote positioning movement for the young-adult group was mostly completed in their First Submovement phase, while the elderly subjects spent most of their movement time on the Adjustment Submovement phase. These results support the proposition that different age groups exhibit different kinds of movement patterns.

Characterization of the anoxia-induced long-term synaptic potentiation in area CA1 of the rat hippocampus

1. The purpose of the present study was to characterize the mechanisms underlying the anoxia-induced long-term potentiation (LTP) of glutamatergic synaptic transmission in the CA1 region of rat hippocampus by use of intracellular recordings in vitro. 2. In response to superfusion of an anoxic medium equilibrated with 95% N2 - 5% CO2, the initial slope (measured within 3 ms from the onset of the synaptic response) of the excitatory postsynaptic potential (e.p.s.p.) generated in the hippocampal CA1 neurones by stimulation of Schaffer collateral-commissural afferent pathway was significantly decreased by 91.3 +/- 4.9% (n = 10) within 10 min of the anoxic episode. The reduction of the initial slope of the e.p.s.p. was accompanied by a transient membrane hyperpolarization followed by a sustained depolarization (10.8 +/- 1.7 mV, n = 10), along with a reduction in membrane input resistance (69.3 +/- 4.8% of control, n = 10). On return to reoxygenated medium, the e.p.s.p. slope returned to the control value within 8-10 min and was subsequently and progessively potentiated to reach a plateau (195.6 +/- 14.7% of control, n = 10) 15-20 min after return to control ACSF. This anoxic episode-induced persistent potentiation of synaptic transmission lasted for more than 1 h and was termed anoxic LTP. 3. The anoxic episode induced a persistent potentiation of the initial slopes of both pharmacologically isolated alpha-amino-3-hydroxy-5-methyl-4-isoxazola-propionate (AMPA) receptor-mediated e.p.s.p. (e.p.s.p.AMPA) and N-methyl-D-aspartate (NMDA) receptor-mediated e.p.s.p. (e.p.s.p.NMDA) with a similar time course and magnitude. The sensitivity of postsynaptic neurones to NMDA (10 microM), but not to AMPA (10 microM) was also persistently potentiated following the anoxic episode. In addition, the anoxia-induced LTP of the initial slope of e.p.s.p.AMPA was accompanied by a decrease in the magnitude of paired-pulse facilitation (PPF; from 106.8 +/- 17.6 to 46.6 +/- 18.4%, n = 6), a phenomenon which was associated with presynaptic transmitter release mechanisms. 4. The induction of the anoxic LTP is dependent on the extracellular Ca2+ concentration. The induction of the anoxic LTP was completely abolished when the external Ca2+ was removed and substituted with equimolar Mg2+. Moreover, the anoxic LTP was completely abolished in neurones intracellularly recorded with Ca2+ chelator bis-(O-aminophenoxy)-N,N,N',N'-tetraacetic acid (BAPTA, 500 mM). 5. Occlusion experiments were performed to examine whether the sustained enhancement of the initial slope of the e.p.s.p. produced by tetanic stimulation and the anoxic episode share common cellular mechanisms. Three episodes of tetanic stimulation were delivered to saturate the LTP, following which a long period (15 min) of anoxia failed to cause a further potentiation of the initial slope of the e.p.s.p. Similarly, prior induction of anoxic LTP also significantly attenuated the subsequent synaptic potentiation induced by a high-frequency tetanic stimulation (100 Hz for 1 s duration). These data imply that these two forms of synaptic plasticity may share a common cellular mechanism. 6. These results provide strong evidence that the generation of the anoxia-induced LTP of glutamatergic synaptic transmission in the CA1 region of rat hippocampus probably involves both of the presynaptic and postsynaptic loci. The mechanisms underlying the persistent potentiation are likely to be attributable to an enhancement of presynaptic glutamate release and a selective upregulation of postsynaptic NMDA receptor-mediated synaptic response through the Ca2+-dependent processes.

Hepatitis in patients with end-stage renal disease

Hepatitis B and hepatitis C are two common pathogens causing chronic hepatitis in patients with end-stage renal disease (ESRD). With the acceptance of hepatitis B s antigen (HBsAg) screening, infected patients have been identified and isolated over the past 20 years. Consequently, hepatitis B is now being seen less frequently in dialysis units. Even though hepatitis B has become less of a problem, non-A, non-B hepatitis has been recognized as a significant problem since 1979. With the availability of serological testing for hepatitis C virus (HCV), more specific information is now available in regard to HCV infection in dialysis patients. The prevalence of anti-HCV in haemodialysis (HD) patients is quite variable, ranging from 5 to over 50%. Anti-HCV positivity is associated with previous blood transfusions, mode of therapy and duration of haemodialysis. In Spain and Italy, the annual seroconversion rates of HCV antibodies in dialysis patients are 2-9%; this rate was much higher in Taiwan (15%). Whether patients with HCV infection should be identified and isolated during HD treatment is an issue of controversy. Transplantation is associated with increases in hepatitis B virus (HBV) replicative markers. The survival disadvantage in HBsAg-positive recipients usually did not become apparent until 8 years after transplantation. Hepatitis C virus-infected renal transplant recipients are presumably in a similar situation to patients with hepatitis B, although confirmatory data are currently lacking. Coinfection of HBV and HCV may lead to aggressive liver disease and cirrhosis. A hepatitis B vaccine is recommended for all susceptible dialysis patients. Dialysis patients have lower response rates to hepatitis B vaccines than do other people. Currently, no vaccine is available for hepatitis C. To date, there are no effective treatments available for hepatitis B and hepatitis C. Combination therapy with interferon/lamivudine for hepatitis B and interferon/ribavirin for hepatitis C may offer a promise of effective control of viral replication in the future.

Detection of serum transforming growth factor-alpha in patients of primary epithelial ovarian cancers by enzyme immunoassay

Transforming growth factor-alpha (TGF-alpha) is a potent mitogenic polypeptide. It is secreted by a variety of transformed cells and tumors, modifying tumor growth through autocrine or paracrine mechanism. In the present study, serum levels of TGF-alpha were determined by enzyme-linked immunosorbent assay (ELISA) in 27 normal females, 116 patients with benign ovarian tumors, and 42 patients with epithelial ovarian cancers (10 with stage I, 7 with stage II, 19 with stage III, and 6 with stage IV). The ELISA assay could detect a minimum level of serum TGF-alpha concentration at 10 pg/ml. Serum samples were obtained from normal females and from patients with benign or malignant ovarian tumors before initial surgery. The detectable rates were 11% (3/27) in normal females, 28% (32/116) in benign ovarian tumors, and 62% (26/42) in ovarian cancers. The detectable rates in serous and endometrioid ovarian cancers were 71 and 70%, respectively, which were higher than the rate of 33% in mucinous type. However, there was no obvious relationship between the detectability of serum TGF-alpha and the stages of ovarian cancers. The mean concentration of TGF-alpha in ovarian cancer was 159.8 pg/ml, which was significantly higher than 27.7 pg/ml in benign ovarian tumors (P < 0.001) as well as 15 pg/ml in normal females (P < 0.001). The mean concentrations of serum TGF-alpha in stages I to IV ovarian cancers were 133.5, 96.2, 194.8, and 178.3 pg/ml, respectively. The mean concentration of serum TGF-alpha in any two stages of ovarian cancers was not statistically different. In conclusion, measurement of serum TGF-alpha can be used as a supplementary tumor marker to differentiate a malignant ovarian tumor from a benign one. However, the concentration of serum TGF-alpha has no special relation with the stage of ovarian cancer itself. Because of the small number of stage I ovarian cancers with detectable TGF-alpha in the present investigation, it would probably not be feasible to differentiate a stage I ovarian cancer from a benign ovarian tumor based only on the level of TGF-alpha in serum.

Combined-modality therapy for squamous carcinoma of the buccal mucosa: treatment results and prognostic factors

BACKGROUND

Reports on locoregional control and survival of squamous cell carcinoma of buccal mucosa are scarce in literature. In this study, a single institutions's experience of combined surgery and postoperative radiotherapy (RT) for buccal mucosal malignancy with favorable results was analyzed and presented. The prognostic factors on locoregional control were also discussed.

METHODS

From January 1988 to July 1994, 57 patients with squamous cell carcinoma of buccal mucosa treated by surgery and RT were reviewed. The distributions according to American Joint Committee on Cancer (AJCC) staging were: stage II, 6; stage III, 21; and stage IV, 30 patients. Total dose of RT at the buccal area ranged from 45 Gy to 68.4 Gy, median 61.2 Gy. Tumor-related factors (AJCC stage, T stage, histologic grading, pathologic tumor invasion to skin of cheek, adjacent bony structures, and regional lymph nodes) and treatment-related factors (surgical margin, radiation dose, and the time interval between operation and RT) were analyzed to determine their influence on locoregional control.

RESULTS

Three-year actuarial locoregional control rate, overall survival rate, and disease-specific survival rates were 64%, 55%, and 62%, respectively. Ten of these 22 patients (45%) with recurrent tumors were reoperated, but only 2 patients were successfully salvaged. Positive surgical margin and tumor invasion to skin of cheek were significantly poor prognostic factors on locoregional control by univariate analysis. In multivariate analysis, tumor invasion to skin of cheek was the only prognostic factor (p = .0014).

CONCLUSIONS

Locoregional failure was the major cause of death for squamous buccal mucosa cancers managed with surgery and RT. Few recurrences could be detected early and successfully salvaged. Skin of cheek involvement is an important prognostic factor for buccal mucosa cancers.

Streptococcal toxic shock syndrome complicating varicella in children

The most common complication in children with varicella is cutaneous superimposed infection with pyogenic bacteria. Group A beta-hemolytic streptococci, which are known to cause life-threatening infections in both previously healthy children and those with underlying diseases, are the most frequently associated pathogens. A newly recognized disease, called streptococcal toxic shock syndrome, is associated with severe morbidity and mortality. We report a 3-year-old boy with a diagnosis of this syndrome who presented with increasing fever, vomiting, and lethargy 7 days after the development of a classic varicella skin lesion. In spite of aggressive fluid supply, administration of inotropic agents, and cardiopulmonary resuscitation, a rapidly deteriorating clinical course led to death 4 hours after hospitalization. This is the first report of this association in Taiwan. Pediatricians evaluating children with varicella must be mindful of the potential for Group A beta-hemolytic streptococcal infection.

Formation of microscale gradients of protein using heterobifunctional photolinkers

Gradients of biological molecules on a microscale have been postulated to elicit cellular responses, such as migration. However, it has been difficult to prepare such gradients for experimental testing. A means for producing such gradients has been developed using a heterobifunctional photolinking agent with laser light activation. The photolinking agent synthesized includes an N-hydroxysuccinimide group and a photoreactive benzophenone (BP) separated by a tetraethylene glycol (TEG) spacer. The presence of the tetraethylene glycol spacer renders the photolinker hydrophilic, a desirable trait for conjugation in aqueous solutions. The linker was then conjugated to R-phycoerythrin (R-PE), a fluorescent protein. The resulting photolinker-R-phycoerythrin conjugate (BP-TEG-PE) was then immobilized onto a polystyrene surface by laser irradiation on a motorized stage. By varying exposure time of the sample to the beam, the amount of BP-TEG-PE immobilized on the surface was changed over an order of magnitude over a distance of 250 microns. This method can be applied to prepare gradients of proteins that elicit biological responses, such as extracellular matrix proteins or growth factors, and to study the biological effects of such gradients.

Risk factor of complications requiring neurosurgical intervention in infants with bacterial meningitis

Among 50 consecutive cases of bacterial meningitis in infants aged 6 months or less, 9 (Group I) were confirmed to have complications requiring neurosurgery during the first 2 weeks of antibiotic treatment. Neurosurgery was performed in 40, 33, and 30% of cases caused by Streptococcus pneumoniae, Pseudomonas aeruginosa, and Escherichia coli, respectively. There were 5 cases of subdural empyema, 1 case of brain abscess, 1 case of subdural empyema and brain abscess, and 2 cases of ventriculitis with severe hydrocephalus. All complications requiring neurosurgery were initially detected by cranial ultrasonography. The other 41 patients who did not undergo neurosurgery were classified as Group II. Comparison of clinical presentations and laboratory findings between the two groups showed that Group 1 contained more patients with a history of inadequate treatment, and longer duration of illness before diagnosis. Except for prolonged disturbance of consciousness, there was no difference between the two groups in clinical and laboratory data on admission or in clinical course during therapy. Due to the high incidence of complications requiring neurosurgical treatment, cost-effective cranial ultrasound is recommended for screening every young infant with bacterial meningitis, especially in cases caused by S. pneumoniae.

Cutaneous sinus tract caused by vertical root fracture

This report presents a rare case of odontogenic cutaneous sinus tract caused by a vertical root fracture. The root-fractured molar was probably caused by an accidental blow by a cow 3 years ago. Despite all treatments by physicians and surgeons for nearly 1 year, the sinus tract recurred repeatedly. After diagnosis and extraction of the fractured molar by the dentist, the sinus tract healed uneventfully in a month.

Activity concentrations and population dose from radium-226 in food and drinking water in Taiwan

The purpose of this study was to determine the radioactivity of 226Ra in environmental samples in Taiwan. Fish, pork, rice, flour, chicken, vegetable, milk, fruit, egg and water samples were collected and pretreated by radiochemical procedure to extract the 226Ra, and the activity concentrations of 226Ra were determined using a liquid scintillation counter. The 226Ra content of groundwater was 12.0 mBq l-1. The 226Ra contents of the food ranged from 0.02 Bq kg-1 fresh to 0.17 Bq kg-1 fresh. The annual internal dose from ingestion of 226Ra from food and drinking water per caput was evaluated to be 7.5 microSv.

A variant form of ETS1 induces apoptosis in human colon cancer cells

We have previously shown that the human ETS1 protein (p51-ETS1), when ectopically expressed in colon cancer cell lines, is able to reduce its tumorigenicity without affecting its growth properties. To understand the mechanism of tumor reduction, we have expressed two different forms of ETS1 in colon cancer cell lines. Data presented in this paper indicate that the naturally occurring spliced variant protein, p42-ETS1, lacking the region encoded by ETS1 exon VII, represses the tumorigenicity, while p51-ETS1 reduces the tumorigenicity. Repression of tumorigenicity mediated by p42-ETS1 appears to be caused by its ability to induce apoptosis in epithelial cancer cells. This work can have profound medical significance in that it may open up new insights into the potential role of the p42-ETS1 in the induction of apoptosis in epithelial cell cancers and may provide a rationale for its use for potential gene therapy experiments to initiate cell death in cancer cells.

Autonomic involvement in Wilson's disease: a study of sympathetic skin response and RR interval variation

Autonomic nervous system involvement in Wilson's disease (WD) was studied in 25 patients by sympathetic skin response (SSR) and RR interval variation (RRIV). The control group consisted of age-matched healthy subjects. Palmar SSRs were obtained by central activation from median nerve stimulation and by activation of sympathetic trunk from magnetic stimulation of the neck. Electric SSRs were prolonged in 11 patients and absent in 2; magnetic SSRs were delayed in 4 and absent in 1; and the sympathetic central conduction time was prolonged in 3. The mean latencies and mean central conduction of the SSRs were all significantly prolonged in WD when compared to the control group. On the other hand, parasympathetic function was abnormal in 3 patients only during forced deep breathing, and as a group only mean D% was significantly reduced. The present findings suggest that autonomic dysfunction may occur in WD, and that sympathetic function is predominantly affected, mainly due to central involvement.

Hepatitis B vaccine in hemodialysis patients with hepatitis C viral infection

Patients on hemodialysis therapy are at a relatively high risk of exposure to hepatitis B virus (HBV) infection. The prevalence of hepatitis C virus (HCV) infection is even higher and was reported as 33.2% in Taiwan. Although the efficacy of hepatitis B vaccine was well documented, the vaccination schedule in hemodialysis patients is not clearly defined. And under such a high prevalence of HCV infection, little is known about the influence of HCV imposing on HBV vaccination. We studied 50 chronic hemodialysis patients who were serologically negative for the hepatitis B surface antigen (HBsAg), the antibody to the hepatitis B surface antigen (anti-HBs) and the antibody to the hepatitis B core antigen (anti-HBc); 26 of them were positive for the antibody to hepatitis C virus (anti-HCV) test. Recombinant hepatitis B vaccine (Engerix-B) 40 micrograms per dose was administered by the intramuscular route at deltoid region at 0, 1, 2, 6 and 12 months respectively to all the patients. Forty-six patients had completed the study. The effective seroconversion rate (serum anti-HBs titer > 10 mIU ml-1) at 1 month after the final vaccine was 76.1% (35/46). The effective conversion rates of the anti-HCV(+) group to the anti-HCV(-) were 75% versus 77.3% (P = 0.857). Geometric mean anti-HBs titers were 177.67 mIU ml-1 versus 189.28 mIU ml-1 (P = 0.867). Our results showed that five-dose injections of HBV vaccine do not present a superior outcome to the four-dose regimen comparing to published data. The status of positivity of anti-HCV do not pose an suboptimal effect on HBV vaccination of hemodialysis patients.

Bilateral diaphragmatic paralysis--a rare cause of acute respiratory failure managed with nasal mask bilevel positive airway pressure (BiPAP) ventilation

A 68 yr old woman presented with acute respiratory failure. She was suspected of having a phrenic-diaphragmatic impairment, without evidence of an intrinsic lung disease or generalized neuromuscular disorder, after 3 weeks of prolonged mechanical ventilation. A series of studies, including fluoroscopy, phrenic nerve stimulation test and diaphragmatic electromyography, was performed before the diagnosis of bilateral diaphragmatic paralysis (BDP) was confirmed. The patient was successfully weaned from the conventional mechanical ventilator, and was placed on nasal mask bi-level positive airway pressure (BiPAP) ventilation. A high degree of clinical suspicion of bilateral diaphragmatic paralysis should always be raised in patients suffering respiratory failure without definite predisposing factors. Weaning with noninvasive nasal mask ventilation should be tried first instead of direct tracheostomy.

Serum beta-carotene level, arsenic methylation capability, and incidence of skin cancer

To elucidate the associations of arsenic-induced skin cancer with serum beta-carotene level and arsenic methylation capability, a total of 654 residents of age 30 or older were recruited from three arseniasis-hyperendemic villages in Taiwan and regularly examined for skin lesions during the follow-up period. There were 33 cases affected with newly diagnosed skin cancer during the follow-up, giving an incidence of 14.74 per 1000 person-years. Although most study subjects had stopped consuming high-arsenic artesian well water more than 20 years ago, the risk of skin cancer was found to increase significantly with cumulative arsenic exposure before the cessation of drinking artesian well water in a dose-response relationship. Frozen serum samples collected at the recruitment from newly developed skin cancer cases and matched controls were tested for beta-carotene levels by high-performance liquid chromatography. Frozen urine samples of these subjects were examined by high-performance liquid chromatography to speciate arsenite (AsIII), arsenate (AsV), monomethylarsonic acid (MMA), and dimethylarsinic acid and then quantitated by hydride generator combined with atomic absorption spectrometry. Skin cancer cases had a significantly lower serum level of beta-carotene than matched healthy controls. Although the primary methylation capability indexed by the ratio of MMA/(AsIII + AsV) was greater in cases than in controls, the secondary methylation capability indexed by the ratio of dimethylarsinic acid/MMA was lower in cases than in controls. An elevated proportion of MMA in total urinary arsenic level was associated with an increased risk of skin cancer. Subjects with a cumulative arsenic exposure of > or = 20.0 mg/liter-year and a proportion of MMA in total urinary arsenic level >26.7% had a multivariate-adjusted odds ratio of developing skin cancer as high as 20.91 (95% confidence interval, 2.63-166.5) compared wih those who had a cumulative arsenic exposure of <20.0 mg/liter-year and a MMA percentage of < or = 26.7%. Whether the association with capability of inorganic methylation is also applied to cancers of internal organs, including lung, liver, and urinary bladder, remains to be elucidated.

Occupational neurotoxic diseases in Taiwan: a review of the outbreaks and clinical features

In the past 20 years, several outbreaks of neurotoxic disease due to occupational exposure have occurred in Taiwan. The most notorious outbreaks were 'Yu-cheng' due to contamination of polychlorinated biphenyls in cooking oil, lead poisoning in battery manufacturers and workers in a ship-scrapping yard, tile factory and battery recycling plants, and n-Hexane intoxication in press-proffers and ball-manufacturers. In addition, there were manganese intoxication in ferromanganese smelters, mercury intoxication in lamp-socket workers, carbon disulfide intoxication in viscose rayon workers and hydrogen sulfide intoxication in chemical synthetic plants. Although the incidence of occupational neurotoxic diseases has increased, the real incidence is probably still underestimated. The reasons for the underestimation include: 1) the education for workers in industrial hygiene is inadequate; 2) high risk workers are not screened well; 3) physicians are not well trained in early diagnosis of occupational diseases; 4) material safety data information is not readily available in the factories; and 5) the threshold limit values for toxic substances are relatively high in Taiwan, compared with other developed countries.

Predialysis glycemic control is an independent predictor of clinical outcome in type II diabetics on continuous ambulatory peritoneal dialysis

OBJECTIVE

To evaluate the correlation between predialysis glycemic control and clinical outcomes for type II diabetic patients on continuous ambulatory peritoneal dialysis (CAPD).

DESIGN

Sixty type II diabetic patients on CAPD were classified into 2 groups according to the status of glycemic control. In group G (good glycemic control), more than 50% of blood glucose determinations were within 3.3-11 mmol/L and the glycosylated hemoglobin (HbA1C) level was within 5-10% at all times. In group P (poor glycemic control), fewer than 50% of blood glucose determinations were within 3.3-11 mmol/L or HbA1C level was above 10% at least once during the follow-up duration. In addition to glycemic control status, predialysis serum albumin, cholesterol levels, residual renal function, peritoneal membrane function, and the modes of glycemic control were also recorded.

SETTING

Dialysis Unit, Department of Nephrology of a single university hospital.

PATIENTS

From February 1988 to October 1995, 60 type II diabetic patients receiving CAPD for at least 3 months were enrolled.

MAIN OUTCOME MEASURES

Morbidities before and during the dialysis period, patient survival, and causes of mortality.

RESULTS

The patients with good glycemic control had significantly better survival than patients with poor glycemic control (p < 0.01). There was no significant difference in predialysis morbidity between the two groups. No significant differences were observed in patient survival between the patients with serum albumin greater than 30 g/L and those with less than 30 g/L (p = 0.77), with cholesterol levels greater or less than 5.18 mmol/L (p = 0.73), and with different peritoneal membrane solute transport characteristics evaluated by peritoneal equilibration test (p = 0.12). Furthermore, there was no significant difference in survival whether the patients controlled blood sugar by diet or with insulin (p = 0.33). Cardiovascular disease and infection were the major causes of death in both groups. Although good glycemic control predicts better survival, it does not change the pattern of mortality in diabetics maintained on CAPD.

CONCLUSIONS

Glycemic control before starting dialysis is a predictor of survival for type II diabetics on CAPD. Patients with poor glycemic control predialysis are associated with increased morbidity and shortened survival.

Variations of the middle and inferior right hepatic vein: application in hepatectomy

We evaluated the anatomic variations of the middle right hepatic vein (MRHV) and inferior right hepatic vein (IRHV) and their clinical application to the possibility of right subtotal hepatectomy. In 400 of normal livers studied with ultrasound, the IRHV was found to drain segment 6 of the liver and flow into the inferior vena cava (IVC) in 72 (18%) cases. In 22 (5.5%) cases, the MRHV was found to drain segment 5 of the liver and flow into the IVC. The size of the IRHV ranged from 0.1 cm to 0.8 cm with an average of 0.46 cm. For the MRHV, the sizes ranged from 0.1 cm to 0.9 cm with an average of 0.34 cm. In 10/79 (12.6%) cases the IRHV and in 4/ 22 (18.1%) cases the MRHV were bigger than the right hepatic vein (RHV). The distance between the RHV and IRHV ranged from 3 cm to 5 cm with an average of 3.7 cm. The distance between the RHV and MRHV ranged from 3 cm to 3.3 cm with an average of 3.1 cm. A hyperechoic edge, similar to that of the portal vein, was observed at the wall of the hypertrophic IRHV and was 0.3 cm or larger in size. Preoperative delineation of this complex venous anatomy is very important. It provides vital information in the preoperative evaluation needed before performing a right subtotal hepatectomy with preservation of segment 6 or segment 5 of the liver, and with RHV resection. Prior to undertaking a right hepatectomy, clamping the hypertrophic MRHV and IRHV electively may minimize intra-operative blood loss and extrahepatic spread of the malignancy.

Unusual presentations of extrapulmonary tuberculosis in three hemodialysis patients

We report three patients who received maintenance hemodialysis and suffered from extrapulmonary tuberculosis with unusual presentations. The first patient presented with fever of unknown origin. All studies showed negative findings except high erythrocyte sedimentation rate and high value of C-reactive protein. He failed to response to broad-spectrum antibiotics but showed a complete response to antituberculosis therapy. The second patient presented with right supraclavicular lymphadenopathy and weakness. Lymph node biopsy revealed caseating granuloma with positive acid-fast bacilli. The third patient presented with tumor mass of left sternoclavicular joint for which malignancy was suspected initially. Ultimately, tuberculosis was documented by histopathologic studies showing caseating granuloma. All three patients had normal findings of chest x-ray and did not have previous history of tuberculosis and diabetes mellitus.

L-deprenyl (selegiline) limits the repetitive firing of action potentials in rat hippocampal CA1 neurons via a dopaminergic mechanism

The effects of L-deprenyl (selegiline), a highly selective monoamine oxidase type B (MAO-B) inhibitor, on cell excitability of rat hippocampal CA1 neurons were examined in slice preparations using intracellular recording techniques. Superfusion of L-deprenyl (10 and 20 microM) reversibly limited the repetitive firing (RF) of action potentials elicited by injection of depolarizing current pulses (100 ms) into the pyramidal cells. At a concentration of 1-50 microM, L-deprenyl did not alter resting membrane potential or input resistance of the hippocampal CA1 neurons. The limitation of RF by L-deprenyl (20 microM) was accompanied by the reduction of the maximal rate of rise (Vmax) of the action potentials in a non-voltage-dependent manner. In 80% of recorded cells, application of L-deprenyl (20 microM) produced an increase in the amplitude and duration of afterhyperpolarization (AHP). The limitation of L-deprenyl on RF was mimicked by other MAO-B inhibitors, pargyline and 4-phenylpyridine. In addition, the ability of L-deprenyl to limit RF was not observed in the hippocampal CA1 neurons taken from dopamine (DA)-depleted rats. Moreover, we also observed that the L-deprenyl-induced limitation of RF was specifically antagonized by (+/-)-7-bromo-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzaz epine (SKF-83566, 5 microM), a selective D1 dopaminergic receptor antagonist. However, the D2 dopaminergic receptor antagonist, sulpiride (5 microM), had no effect on L-deprenyl's action. These results indicate that the MAO-B inhibitory ability leading to an increase of the dopaminergic tone in the hippocampus is involved, at least in part, in the L-deprenyl-induced reduction of neuronal excitability in the CA1 region of rat hippocampus and that the D1 dopaminergic receptor is involved in L-deprenyl's action.

Light-induced fluorescence spectroscopy to differentiate benign and malignant uterine cervical lesions

In Taiwan, cervical cancer is the leading malignancy among women. For the early detection of cervical neoplasia, light-induced fluorescence spectroscopy was conducted ex vivo to assess the ability of this technique to differentiate cervical neoplastic tissue (20 samples) from normal or inflammatory cervical tissue (37 samples) at an excitation wavelength of 280 nm. The principal fluorescent peaks occurred within +/- 5 nm of 330 nm and 470 nm emission. At 330 nm emission, the spectrum of the normal or inflammatory tissue was significantly stronger than that of the neoplastic tissue after are normalization. However, at 470 nm emission, the spectrum of the normal or inflammatory tissue was significantly weaker than that of the neoplastic tissue. A diagnostic algorithm based on the ratio of relative intensities of 330 nm to 470 nm emission within the 5 +/- nm peak area of each sample was calculated and paired. The ratios showed that histologically neoplastic lesions could be distinguished from inflammatory samples using a 280-nm-excitation wavelength with a sensitivity, specificity and positive predictive value of 94%, 82% and 73%, respectively. The average ratio of malignant or dysplastic cervical samples was significantly greater than that of the inflammatory samples (p < 0.001). Our ex vivo study indicated that light-induced fluorescence spectroscopy may be useful in differentiating malignant or premalignant from normal or inflammatory cervical tissue.

Simultaneous team approach of a crown-lengthening procedure and an operative restoration: technique and long-term effect

Traditionally, crown-lengthening procedures to expose subgingival caries for operative restorative work are carried out in a two-stage approach. A disadvantage of this procedure is that the gingival margin associated with the treated tooth moves apically; this may create an esthetic problem. Resin-modified glass-ionomer cement has been demonstrated to have good biocompatibility with dental hard and soft tissues. Surgical and restorative procedures were combined at the same appointment in an effort to achieve a restoration with minimal change in the gingival margin. Four patients have been treated with this one-stage team approach and followed for 8 to 13 months. The clinical results demonstrated this team approach procedure is excellent for the dentition when esthetics is a consideration.

Dietary fat affects lipids and anti-cardiolipin antibody levels in autoimmune-prone NZB/W F1 mice

Studies in autoimmune-prone NZB/W F1 mice have demonstrated that the amount of dietary fat can affect autoantibody production and the disease course of autoimmune diseases. Anti-cardiolipin antibodies have been found to play a major role in thrombus formation and the increase of abortion rate in both human lupus patients and murine lupus. The present study investigated further the effect of dietary fat on lipid and anti-cardiolipin antibody production in autoimmune-prone mice. Two groups of NZB/W F1 mice were fed on diets containing 200 g dietary fat/kg and 50 g dietary fat/kg respectively, the fat being composed of equal amounts of lard and soyabean oil. Serum levels of lipids, immunoglobulin (Ig) anti-single stranded DNA and anti-cardiolipin antibodies were followed regularly every month and mice were killed for in vitro experiments after 5 months on the experimental diets. The results showed that serum triacylglycerol concentration was lower in mice fed on the high-fat diet than in those fed on 50 g fat/kg. There was no significant difference in hepatic lipid contents; however, the fatty acid contents were different between these two groups. Hepatic linoleic acid (18:2n-6) and arachidonic acid (20:4n-6) concentrations were higher in mice fed on the high-fat diet. There were no significant differences in serum IgM concentrations or IgM anti-cardiolipin antibody levels between these two groups. However, IgG anti-cardiolipin antibody levels were higher in mice fed on the high-fat diet at the age of 3-4 months. Total serum IgG concentration was noted to be higher, but in contrast, serum IgA was lower, in the high-dietary-fat group. These findings suggest that high dietary fat may affect lipid metabolism and autoantibody levels in autoimmune diseases.

Presynaptic and postsynaptic striatal dopaminergic function in patients with manganese intoxication: a positron emission tomography study

We performed PET on four patients with chronic industrial Mn intoxication; presynaptic and postsynaptic dopaminergic function were measured with [18F]6-fluoro-L-dopa (6FD) and [11C]raclopride (RAC). All patients had a rigid-akinetic syndrome; they had no sustained benefit from L-dopa. Influx constants (Ki) of 6FD were normal in the caudate and putamen. RAC binding was mildly reduced in the caudate and normal in the putamen. We conclude that nigrostriatal dopaminergic dysfunction is not responsible for the parkinsonism caused by chronic Mn intoxication. The pathology is likely to be downstream of the dopaminergic projection.