Overexpression of protein tyrosine phosphatase-alpha (PTP-alpha) but not PTP-kappa inhibits translocation of GLUT4 in rat adipose cells

Protein tyrosine phosphatases (PTPases) are likely to play important roles in insulin action. We recently demonstrated that the nontransmembrane PTPase PTP1B can act as a negative modulator of insulin-stimulated translocation of GLUT4. We now examine the role of PTP-alpha and PTP-kappa (two transmembrane PTPases) in this metabolic action of insulin. Rat adipose cells were transfected with either PTP-alpha or PTP-kappa and effects of these PTPases on the translocation of a cotransfected epitope-tagged GLUT4 were studied. Cells overexpressing wild-type PTP-alpha had significantly lower levels of cell surface GLUT4 in response to insulin and a threefold decrease in insulin sensitivity when compared with control cells expressing only tagged GLUT4. Co-overexpression of PTP-alpha and PTP1B did not have additive effects, suggesting that these PTPases share common substrates. Cells overexpressing either wild-type PTP-kappa or catalytically inactive mutants of PTP-alpha had dose-response curves similar to those of control cells. Since overexpression of PTP-alpha, but not PTP-kappa, had effects on translocation of GLUT4, our data suggest that PTPalpha may be a specific negative modulator of insulin-stimulated glucose transport.

Kinetics of germanium dioxide in rats

The kinetics of germanium dioxide (GeO2) in single dose and repeated exposures were investigated in male Wistar rats. In the single dose GeO2 (100 mg/kg BW, p.o.) exposure study, values of several kinetic parameters were shown as follows, a maximum concentration in serum of 15.5+/-0.7 microg/ml (mean +/- S.E.M.), an absorption half-life of 0.7+/-0.1 h (mean +/- S.E.M.), an elimination half-life of 2.3+/-0.5 h (mean +/- S.E.M.), a distribution of the central compartment Vp (3.1+/-0.3 1, mean +/- S.E.M.), and the apparent volume of distribution of the tissue compartment Vt (8.5+/-2.9 1, mean +/- S.E.M.). In the repeated exposure study, 730+/-92 mg GeO2 in 1 1 double-distilled H2O ( = 100 mg/kg/day) was given daily to rats for 4 weeks (p.o.). After sacrificing the rats, the analysis of tissue distribution showed that GeO2 was accumulated in some important organs or tissues in the body, especially the peripheral nerves and kidney. These results indicate that GeO2 could be absorbed rapidly but had a longer elimination half-life in rats. In addition, GeO2 was accumulated especially in the nerves and kidney following long-term exposure.

Toe transplantation for isolated index finger amputations distal to the proximal interphalangeal joint

Functional deficit following single distal index finger amputations has been considered insignificant, and reconstruction is usually not recommended. Herein, 19 cases of second toe transplantation for reconstruction of isolated index finger amputation distal to the proximal interphalangeal joint are presented with long-term functional results. There are 14 men and 5 women. The average age was 26 years. The toe transplantations were performed either as a primary procedure (5 patients) while the wounds were still open or as a secondary procedure (14 patients) after the wounds healed. In 11 patients, the dominant hand was involved. All toes survived completely, although re-exploration was required in three cases (16 percent). The functional evaluation included (1) sensory recovery, where the average static and moving two-point discrimination were 8 mm (range 4 to 15 mm) and 6 mm (range 2 to 15 mm); (2) motor function, where the average of index-thumb pulp-to-pulp pinch compared with the normal hand was 67.5 percent (range 36 to 96 percent); (3) average range of motion in index finger joints (extension/flexion), where metacarpophalangeal joint was 14/90, proximal interphalangeal joint was 0/94, and distal interphalangeal joint was 19/38; and (4) functional and cosmetic results, where percentage of involvement in daily activities and functional capacity of the reconstructed index were 69 percent and 70.5 in average, respectively, over a total score of 100. Average scores of aesthetic appearance and acceptability of donor-site deformity were 74 and 87.5 over a total score of 100, respectively. Toe transplantation for distal index finger amputations improved hand function when performed in selected patients with specific job requirements or high motivation.

No evidence for association of serotonin-2A receptor variant (102T/C) with schizophrenia or clozapine response in a Chinese population

The serotonin hypothesis in schizophrenia had regained interest with the superior efficacy of clozapine in the refractory schizophrenic patients. Among the serotonin receptors, the serotonin 2A (5HT2A) receptor subtype is the most widely studied. Previous studies on the association between a silent mutation polymorphism of the 5HT2A gene (102T/C) and schizophrenia or clozapine response have yielded conflicting findings. Therefore, we investigated whether these genetic variants of the 5HT2A receptor are associated with schizophrenia or with response to clozapine treatment in a Chinese population. Ninety-seven schizophrenic patients and 101 control subjects were included in the study. The receptor variants were found at similar frequencies in schizophrenic patients and healthy control subjects. Also, we did not find the variants to influence the response to clozapine in schizophrenic patients. We suggest that the assessment method of clozapine response and the ethnicity may influence the result.

Triflavin potentiates the antiplatelet activity of platelet activating factor receptor antagonist on activated neutrophil-induced platelet aggregation

In this study, specific platelet activating factor (PAF) receptor antagonist ginkgolide B (BN52021) was tested for its antiplatelet activity in zymosan activated polymorphonuclear neutrophil-induced platelet aggregation. Triflavin was also tested for its antiplatelet activity compared with PAF receptor antagonist. Triflavin, an Arg-Gly-Asp-containing disintegrin purified from venom peptide inhibited platelet aggregation by interfering with the interaction of fibrinogen with the glycoprotein IIb/IIIa complex. Furthermore, we also report an efficient high resolution method for quantitative analysis of PAF using high-performance capillary electrophoresis (HPCE). The supernatant of polymorphonuclear neutrophils after their activation by opsonized zymosan induces the aggregation of washed rabbit platelets. In rabbit platelets, BN52021 (100-1000 microM) only partially inhibited activated polymorphonuclear neutrophil-induced platelet aggregation, and its maximal inhibition was estimated to be about 79%. Triflavin also partially inhibited platelet aggregation about 82% induced by activated polymorphonuclear neutrophils. Furthermore, after treatment with a combination of triflavin (0.26 microM) with various concentrations of BN52021 (4-1000 microM), the inhibitory effect of platelet aggregation was almost completely. This inhibition was greater than that produced by the individual drugs alone. These results indicate that a combination of glycoprotein IIb/IIIa complex and PAF receptor antagonist could completely inhibit activated polymorphonuclear neutrophil-induced platelet aggregation. In addition, the amount of PAF released from zymosan (6 mg/ml)-activated polymorphonuclear neutrophils was accurately calculated about 11.8+/-1.5 ng/10(6) cells, and did not further increase even at a high concentration of zymosan (10 mg/ml). These results suggest that PAF play a major role in the interaction between platelets and polymorphonuclear neutrophils. This interaction may be important in the pathogenesis of thrombosis and inflammatory diseases. Our present findings support the hypothesis that combination therapy with glycoprotein IIb/IIIa complex antagonists and PAF receptor antagonists may represent a new approach to the treatment of ischemic disorders.

The role of pulmonary inflammation in the development of pulmonary hypertension in newborn with meconium aspiration syndrome (MAS)

1. There was no clear correlation between the tracheal aspirate cytokines and the elevation of pulmonary arterial pressure in newborn piglets with MAS. The use of dexamethasone significantly suppressed tracheal aspirate cytokines but did not significantly alter pulmonary arterial pressure. Dexamethasone significantly increased the cardiac stroke volume and blood pressure. 2. Early dexamethasone therapy (< 12 hrs) for one week in infants with MAS significantly improved pulmonary ventilation and facilitated weaning from mechanical ventilation. 3. The mechanisms for the improvement in cardiopulmonary status following early dexamethasone therapy in MAS remain unclear. An overall improvement in cardiac hemodynamics, along with a significant decrease in lung inflammation may be responsible for the improvement.

Follow-up study in patients with no stone retrieval from the bile duct after endoscopic sphincterotomy

BACKGROUND

No stones are retrieved from the bile duct in 10-20% of patients with suspected common bile duct (CBD) stones after endoscopic sphincterotomy (EST). The clinical outcome in these patients remains unclear. This study followed patients from whom no stones were retrieved, to discover their clinical outcome.

METHODS

From October, 1990, to October, 1996, 401 patients with suspected CBD stones received EST for stone removal. Only patients from whom no stones were retrieved from the bile duct were included in this study. All enrolled patients were regularly interviewed and received liver function tests. Sonography, computerized tomography, endoscopic retrograde cholangiopancreatography (ERCP), and/or intrapapillary biopsy were performed as indicated.

RESULTS

Forty-two patients were included in this study. The indications for EST included 34 cases with filling defects in the common bile duct on ERCP and eight cases with suspected impacted stones as seen by imaging studies. After a mean follow-up period of 28.6 months (range, 1-61 months), six patients developed biliary stones, four had carcinoma of the ampulla of Vater, one was found to have intrabiliary growth of hepatocellular carcinoma, and there was no pathologic change in 31 cases. Of the six patients with formation of biliary stones, two had an intact gallbladder and four had received previous cholecystectomy. Of the four patients with ampullary tumors, three were diagnosed by intrapapillary biopsy soon after EST, and one was diagnosed nine months later.

CONCLUSIONS

Biliary problems were found in 26% of patients soon after EST, although no stones were retrieved from the bile duct. Regular follow-up is warranted.

Prevention of chronic lung disease in preterm infants by early postnatal dexamethasone therapy

Recent studies suggest that early dexamethasone therapy may lessen the pulmonary inflammation in preterm infants with respiratory distress syndrome (RDS). To investigate whether early (<12 hr) postnatal dexamethasone therapy would reduce the incidence of chronic lung disease (CLD), a randomized, double-blind, controlled trial was conducted in 40 infants (birth weights from 500 to 1,999 gm) who had severe RDS and required mechanical ventilation within 6 hr of birth. All infants received one dose of Survanta before they were randomly assigned to control (saline placebo) or dexamethasone-treated groups (0.5 mg/kg/d for 1 week, then tapered over 3 weeks). Sequential analysis was performed with the end point of assessment being the presence or absence of CLD on postnatal Day 28. Statistical significance favoring dexamethasone was reached when 12 consecutive pairs in which one infant had CLD and the other did not have CLD showed that ten pairs favored dexamethasone and two pairs favored control treatment. Among the survivors, 12/15 were extubated in the dexamethasone group and 9/16 in the control group at the end of study. Infants in the treated group had transient hyperglycemia and hypertension. There was no difference between the groups in mortality and in incidence of sepsis or intraventricular hemorrhage. We conclude that early postnatal dexamethasone therapy is potentially effective in the lessening of CLD in preterm infants. To substantiate our result, large randomized controlled trials are needed and warranted.

Noise reduction of VQ encoded images through anti-gray coding

Noise reduction of VQ encoded images is achieved through the proposed anti-gray coding (AGC) and noise detection and correction scheme. In AGC, binary indices are assigned to the codevector in such a way that the 1-b neighbors of a code vector are as far apart as possible. To detect the channel errors, we first classify an image into uniform and edge regions. Then we propose a mask to detect the channel errors based on the image classification (uniform or edge region) and the characteristics of AGC. We also mathematically derive a criterion for error detection based on the image classification. Once error indices are detected, the recovered indices can be easily chosen from a "candidate set" by minimizing the gray-level transition across the block boundaries in a VQ encoded image. Simulation results show that the proposed technique provides detection results with smaller than 0.1% probability of error and more than 86.3% probability of detection at a random bit error rate of 0.1%, while the undetected errors are invisible. In addition, the proposed detection and correction techniques improve the image quality (compared with that encoded by AGC) by 3.9 dB.

Automatic facial feature extraction by genetic algorithms

An automatic facial feature extraction algorithm is presented. The algorithm is composed of two main stages: the face region estimation stage and the feature extraction stage. In the face region estimation stage, a second-chance region growing method is adopted to estimate the face region of a target image. In the feature extraction stage, genetic search algorithms are applied to extract the facial feature points within the face region. It is shown by simulation results that the proposed algorithm can automatically and exactly extract facial features with limited computational complexity.

Calcinosis cutis following extravasation of calcium gluconate in neonates

Neonatal hypocalcemia is not an uncommon condition, especially in the premature neonate. It is effectively treated by intravenous infusion with calcium gluconate. We treated nine neonates with subcutaneous calcium deposition following calcium replacement with calcium gluconate from Jan. 1997 to Dec. 1997. Three of the infants were born to diabetic mothers, two had perinatal asphyxia and four were born prematurity. The average dosing number was 7.4 (5 to 9 doses). The onset of calcinosis cutis was 5 to 11 days after the first dose. The replacement of calcium gluconate caused amorphous masses at the site of extravasation and contracture of joint movement. A radiographic study was performed to determine the extent and course of extravasation, and areas remote from the infusion site also showed calcification. There is no specific mode of treatment except supportive management and a skin graft. The patient could functionally recover with cosmetic residue. In our follow-up clinics, all infants completely recovered without functional limitations.

Effects of intraventricular norepinephrine on LH release in short- and long-term ovariectomized steroids-primed rats

This study examined the noradrenergic mechanism in regulation of luteinizing hormone (LH) release in short- and long-term ovariectomized (OVX) steroids-primed rats. All rats were OVX on the diestrous day 1(D1) morning about 1000 h. After OVX, rats in the short-term OVX group were immediately primed with estradiol (E2, 0.1 mg/kg BW s.c.), fitted with atrial Silastic tubing, and a guide cannula in the right lateral cerebroventricle stereotaxically. Rats in the long-term OVX group received the same treatment (E2, atrial tubing and guide cannula implantation) three weeks later. Rats in both groups received progesterone (2 mg/rat s.c.) at 0930 h on the next day after E2. At 1000 h, intraventricular administration of norepinephrine HCl (NE, 0.01, 0.1, or 1.0 microgram in 2 microliters saline) was given. In short-term OVX-steroids-primed rats, NE did not alter LH levels in the peripheral plasma within 60 or 100 min. By contrast, in long-term OVX-steroids-primed rats, 1.0 microgram of NE gradually decreased plasma LH concentrations, which became significantly different from the initial value at the 60 min time point after treatment. On the other hand, intraventricular injection of 5 ng of the LH-releasing hormone (LHRH) elevated plasma LH concentrations within 10 min in both groups of rats, but at different efficacy: a brief release of LH in short-term OVX-steroids-primed rats and a prolonged release of LH in long-term OVX-steroids-primed rats. These results indicated that the interval after OVX plays a critical role in modulating the responsiveness to NE and LHRH in the steroids-primed OVX rats.

Single versus double arterial anastomoses in combined second- and third-toe transplantation

Combined second and third toe transplantation is one good option for reconstruction of multiple digit amputation. However, the use of one or two arteries for pedicle anastomoses, which may influence the vascular complication and success rate, has never been addressed in the literature. This study includes a retrospective review of 57 combined second and third toe transplantation in 54 patients performed from February of 1983 through December of 1996. Group I, composed of 41 transplantations, underwent one arterial anastomosis, and group II, composed of 16 transplantations, underwent double arterial anastomoses during surgery if there were two recipient arteries available or whenever the second and third toes showed inadequate blood perfusion after one arterial anastomosis. In group I, 10 transplantations (24.4 percent) required re-exploration with a success rate of 92.7 percent (38 out of 41 transplantations). In group II, only one transplantation (6.2 percent) required re-exploration with successful flap salvage. The success rate was 100 percent for group II. Because the re-exploration and success rates between groups I and II were not statistically significant according to two-tailed Fisher's exact test, the combined second and third toe transplantation is a reliable procedure using either single or double arterial anastomoses.

Enhancer elements activate the weak 3' splice site of alpha-tropomyosin exon 2

We have identified four purine-rich sequences that act as splicing enhancer elements to activate the weak 3' splice site of alpha-tropomyosin exon 2. These elements also activate the splicing of heterologous substrates containing weak 3' splice sites or mutated 5' splice sites. However, they are unique in that they can activate splicing whether they are placed in an upstream or downstream exon, and the two central elements can function regardless of their position relative to one another. The presence of excess RNAs containing these enhancers could effectively inhibit in vitro pre-mRNA splicing reactions in a substrate-dependent manner and, at lower concentrations of competitor RNA, the addition of SR proteins could relieve the inhibition. However, when extracts were depleted by incubation with biotinylated exon 2 RNAs followed by passage over streptavidin agarose, SR proteins were not sufficient to restore splicing. Instead, both SR proteins and fractions containing a 110-kD protein were necessary to rescue splicing. Using gel mobility shift assays, we show that formation of stable enhancer-specific complexes on alpha-tropomyosin exon 2 requires the presence of both SR proteins and the 110-kD protein. By analogy to the doublesex exon enhancer elements in Drosophila, our results suggest that assembly of mammalian exon enhancer complexes requires both SR and non-SR proteins to activate selection of weak splice sites.

An alternative continuous caudal block with caudad catheterization via lower lumbar interspace in adult patients

BACKGROUND

Continuous caudal block with caudad catheterization has not yet been mentioned in literatures. We designed a preliminary study to investigate the feasibleness of this technique, spread of contrast medium under fluoroscopy, and its clinical effectiveness.

METHODS

Ten patients were subjected to epidural block (caudal) for elective anal or vaginal procedures. The entry of the epidural needle was made at the L4-5 interspace either with midline or paramedian approach. Through an 18 G Touhy needle with its bevel facing caudally an epidural catheter was threaded until a length of 10 cm was beyond the point of entry. The presence or absence of paresthesia during the passage of catheter and the ease with which the catheter was inserted were recorded. After the procedure, the course on which the catheter traversed and the spread of the medicinal substance in the epidural space were visualized and studied fluoroscopically using 1 and 3 ml iohexol (omnipaque 300 mg/ml) as contrast medium respectively. Then the patients were brought to operating rooms for anesthesia and surgery. Sensory anesthetic level and motor blockade were evaluated fifteen min after 11-15 ml of 2% lidocaine had been injected through the epidural catheter. During anesthesia vital signs were closely monitored, and adverse reaction if any was evaluated and managed.

RESULTS

The insertion of the epidural catheter was considered easy and caused no paresthesia in nine patients. Catheter insertion encountered moderate resistance and induced paresthesia in one patient. Yet, the catheter was advanced successfully to the expected length. In radiological study with contrast medium, the course of the epidural catheter was not always traceable, while the spread of the contrast medium was clearly identified. Epidural spread occurred in eight patients, left paravertebral spread in one patient, and right retrorectal spread in another one patient. As to clinical assessment, adequate sensory blockade with local anesthetic was gained in 8 patients with well-preserved motor function of the lower limbs. In one patient the caudal block worked well after the withdrawal of the catheter 5 cm in length. Spinal anesthesia was supplemented in one patient due to failure of the caudal block.

CONCLUSIONS

Continuous caudal block with caudawise catheterization via lower lumbar interspaces is feasible (eight of 10 patients in this study) with respect to technique and clinical effect. Paravertebral and retrorectal migrations of the catheter may occur in spite of smooth catheterization. Either migration might lead to a failure of caudal block.

Characterization of a desiccation-related protein in lily pollen during development and stress

This work characterizes a lily (Lilium longiflorum Thunb. cv. Snow Queen) anther (LLA) protein associated with desiccation. Peptide mapping analysis revealed that the abundant LLA-23 doublet contained similar polypeptides, having an isoelectric point of 6.1. Immunoblots of pollen protein from developing anther/pollen confirmed that the LLA-23 protein accumulated only at the later stage of pollen maturation and that the levels remained steady in mature and vital pollen. The accumulation of LLA-23 proteins was correlated with desiccation that naturally occurred in pollen. Subcellular fractionation of pollen proteins revealed that the protein was located in the cytoplasmic fraction. Premature drying of developing pollen confirmed that the concomitant accumulation of LLA-23 was associated with desiccation. Peptide sequence analysis demonstrates similarities between the lily LLA-23 and a family of water-deficit/ripening-induced proteins including LP3 of pine, DS2 of potato, and Asr of tomato and pummelo. In addition, the concomitant accumulation of LLA-23 can be experimentally manipulated by methyl jasmonate (Me-JA) and salicylic acid (SA) as well as by mannitol and methyl viologen. The LLA-23 represents a novel member of the water-deficit/ripening-induced proteins.

Efficacy of nasal intermittent positive pressure ventilation in treating apnea of prematurity

The efficacy of nasal intermittent positive pressure ventilation (NIPPV) in treating apnea of prematurity was evaluated. Apneic preterm infants were randomly assigned to receive either NIPPV or continuous positive airway pressure (NCPAP) for 4 hr when they failed to respond to conservative therapy. The amount of reduction in apneic spells and bradycardia in the two groups after treatment was compared. Thirty-four infants (18 with NIPPV, 16 with NCPAP) were enrolled. Their birth weights ranged from 590-1,880 g (mean, 1,021 g) and gestational ages from 25-32 weeks (mean, 27.6 weeks). The baseline characteristics were comparable in the two groups. Frequency of apnea and bradycardia was reduced during both forms of treatments. However, the infants receiving NIPPV had a greater reduction of apneic spells (P = 0.02) and a tendency to greater decrease in bradycardia (P = 0.09) than those receiving NCPAP. We conclude that NIPPV is more effective than NCPAP in reducing apnea in preterm infants. NIPPV may reduce bradycardia; however, this needs to be validated by a larger number of observations.

Fatal coxsackievirus B infection in early infancy characterized by fulminant hepatitis

OBJECTIVES

to clarify the major features of fatal coxsackievirus B infection characterized by fulminant hepatitis in early infancy.

METHODS

clinical manifestations and laboratory investigations concerning five consecutive young infants with overwhelming coxsackievirus B fulminant hepatitis between 1994 and 1997 were retrospectively reviewed. Aetiological diagnosis was made by viral cultures and confirmed by a neutralization test with a type-specific antiserum.

RESULTS

all five had a deteriorating clinical course of severe hepatitis complicated by disseminated intravascular coagulopathy (DIC). Coxsackievirus B1 infection was established in four patients and coxsackievirus B3 in one. The pathological findings of the two cases illustrated extensive hepatocellular necrosis. Fulminant hepatitis can occur as a leading presentation of disseminated coxsackievirus B infections and dominant the clinical features in neonates and young infants.

CONCLUSIONS

the liver was the target organ of fatal coxsackievirus B infection in our patients. Hepatic involvement progressed rapidly to jaundice and coagulopathy, and was considered to be indicative of poor prognosis. Coxsackievirus B hepatitis may be serious in early infancy.

Quantification analysis for saccadic eye movements

Traditional parameters, such as latency and peak velocity, have been used for quantitative analysis of saccade dynamics. However, saccades of equal magnitude which differ substantially in dynamics may still have the same peak velocity. This lack of selectivity might degrade the efficacy of the peak velocity measurement in discriminating patients from normal subjects. In this study, an alternative parameter, the damping ratio of a second-order response, is proposed to concisely and accurately describe saccadic dynamics. A measurement of damping ratio is made by considering the response curve of saccade as the step response of a second-order transfer function. Using the least-mean-square algorithm, the second-order function has been optimized to fit the response of the saccade dynamics with the latency removed. Nineteen normal subjects (ten young and nine older) and 16 patients of Parkinson's disease (eight mildly affected and eight advanced affected) were tested for eye movements in response to pseudorandom saccadic stimuli. While the traditional peak velocity had difficulties in differentiating between the saccadic dynamics of normal and Parkinson subjects, the damping ratio is sensitive enough not only to highlight the difference between a group of patients mildly affected with Parkinson's disease and an age-matched normal group (p<0.01; abnormal versus normal), but also to distinguish between groups at different ages (p<0.01; younger versus older). It is proposed that the damping ratio could be a useful parameter in analyzing saccadic dynamics.

Epicanthoplasty with modified Y-V advancement procedure

The presence of epicanthal folds and lack of supratarsal folds are unique features in most Asian eyelids. Although many surgical procedures are available to eliminate epicanthal folds, scarring on the medial canthus is still an obstacle for surgeons to overcome. From January of 1989 to November of 1997, we used modified Y-V advancement procedures in 148 cases to correct epicanthal folds in Asian eyelids. Five of those cases involved congenital palpebral anomalies, including congenital entropion, congenital ptosis, and Down syndrome. There were few complications in our series. We believe that the modified Y-V advancement procedure causes minimum scarring on medial canthus in correcting Oriental epicanthal folds and congenital palpebral anomalies. This procedure can also be simultaneously combined with blepharoplasties and corrective procedures of eyelids.

Lymphoepithelial cyst of the parotid gland--a case report

The lymphoepithelial cyst has been commonly termed branchial cleft cyst or branchial cyst. Although many theories, including the branchial apparatus theory, thymic duct theory, and inclusion theory, have been put forward, the etiology is still controversial. Parotid lymphoepithelial cysts are rare and could be divided into two groups, AIDS-related and non-AIDS related, by the relationship with HIV infection. A non-AIDS related lymphoepithelial cyst of left parotid gland in an 81-year-old man presenting as a parotid tumor is described. A left partial parotidectomy was carried out to remove the lesion. There was no recurrence after 2 years. Lymphoepithelial cysts of the parotid gland are often misdiagnosed as other benign tumors in spite of detailed preoperative investigations. Thus a pathological proof is needed for precise diagnosis. In addition, we also need to take the possibility of HIV infection into consideration, although Taiwan is not an AIDS epidemic area.

The antiplatelet activity of rutaecarpine, an alkaloid isolated from Evodia rutaecarpa, is mediated through inhibition of phospholipase C

In this study, the mechanism involved in the antiplatelet activity of rutaecarpine in human platelet suspensions was investigated. In platelet suspensions (4.5 x 10(8)/ml), rutaecarpine (100 and 200 microM) did not influence the binding of FITC-triflavin to platelet glycoprotein IIb/IIIa complex. Additionally, rutaecarpine (200 microM) did not significantly change the fluorescence of platelet membrane labeled with diphenylhexatriene (DPH). On the other hand, rutaecarpine (50 and 100 microM) dose-dependently inhibited the increase in intracellular free Ca2+ of Fura 2-AM loaded platelets stimulated by collagen. Moreover, rutaecarpine (100 and 200 microM) did not significantly affect the thromboxane synthetase activity of aspirin-treated platelet microsomes. Furthermore, retaecarpine (100 and 200 microM) significantly inhibited [3H]arachidonic acid released in collagen-activated platelets but not in unactivated-platelets. Nitric oxide (NO) production in human platelets was measured by a chemiluminesence detection method in this study. Rutaecarpine (100 and 200 microM) did not significantly affect nitrate production in collagen (10 microg/ml)-induced human platelet aggregation. On the other hand, various concentrations of rutaecarpine (50, 100, and 200 microM) dose-dependently inhibited [3H]inositol monophosphate formation stimulated by collagen (10 microg/ml) in [3H]myoinositol-loaded platelets at different incubation times (1, 2, 3, and 5 minutes). It is concluded that the antiplatelet activity of rutaecarpine may possibly be due to the inhibition of phospholipase C activity, leading to reduce phosphoinositide breakdown, followed by the inhibition of thromboxane A2 formation, and then inhibition of [Ca2+]i mobilization of platelet aggregation stimulated by agonists.

Effects of early postnatal dexamethasone therapy on calcium homeostasis and bone growth in preterm infants with respiratory distress syndrome

The effects of dexamethasone therapy on calcium homeostasis and bone growth were evaluated in 49 infants (24 placebo and 25 dexamethasone) who participated in a double-blind trial of early dexamethasone therapy for the prevention of chronic lung disease. Dexamethasone (0.25 mg kg(-1) b.i.d. on d 1-7; 0.12 mg kg(-1) b.i.d. on d 8-14; 0.05 mg kg(-1) b.i.d. on d 15-21; 0.02 mg kg(-1) b.i.d. on d 22-28) or saline placebo was given i.v. Serum calcium (Ca), phosphorus (P) and parathyroid hormone (PTH), and the corresponding urinary excretion of calcium (FECa) and phosphorus (FEP) were measured on d 2, 3, 7, 10, 14, 21 and 28 after starting the study. Radiographic evaluations of bone growth were also evaluated. Infants in the dexamethasone group had significantly higher PTH on d 2 (p < 0.01), 7 and 14 (p < 0.05) than infants in the placebo group. The dexamethasone-treated infants also had significantly higher FEP on d 2, 7 and 14 (p < 0.05) and lower FECa on d 7 and 14 (p < 0.05) than control infants. There was no significant difference between the groups in bone growth during the study. It was concluded that early dexamethasone therapy causes a transient elevation in PTH without apparent change in bone growth. The long-term effect remains to be evaluated further.

Technetium-99m-HMPAO brain SPECT in neonates with hypoglycemic encephalopathy

Regional brain injury in three neonates with hypoglycemic encephalopathy are presented using serial 99mTc-hexamethyl propyleneamine oxime (HMPAO) SPECT and, for comparison, MRI. During the acute stage, both 99mTc-HMPAO SPECT and MRI reveal abnormalities in the posterior cerebrum. Technetium-99m-HMPAO SPECT reveals further areas of insult, for example the frontal lobes. The degree of hypoperfusion correlates with the clinical severity of hypoglycemia during the neonatal period and subsequent neurological sequelae. Follow-up with HMPAO SPECT several months after insult demonstrates persistent hypoperfusion in some areas, mainly in the occipital and posterior parietal regions. MRI can depict morphological changes with superior resolution. Because morphological change generally follows slowly after functional change, MRI is less sensitive than HMPAO SPECT in detecting and predicting the extent of hypoglycemic cerebral injury during the acute phase. HMPAO SPECT during the acute stage is a valuable tool for evaluating the extent and severity of brain injury in neonates with hypoglycemic encephalopathy.

Early weaning induces jejunal ornithine decarboxylase and cell proliferation in neonatal rats

Increased ornithine decarboxylase (ODC) activity is associated with rapid cell proliferation in many cell types. The cellular effects of early weaning on intestinal development are not well established. To investigate whether ODC is involved in intestinal growth after early weaning, we precociously weaned suckling rats on postnatal d 15 and followed through d 21 (6 d after early weaning). Age-matched suckling pups served as controls. Rat pups were killed 1, 2, 3 and 6 d after early weaning and jejunal mucosa was assayed for ODC and sucrase activities, and protein and DNA contents. Jejunal cell proliferation was monitored by bromodeoxyuridine immunohistochemistry. Elevated jejunal ODC activity 1 d after early weaning was the earliest cellular event that was detected in the current study. ODC activity peaked at d 3 (about 15-fold greater than age-matched unweaned suckling controls). Sucrase activity was elevated at d 2 after weaning and peaked at d 3 (about 10-fold greater than controls). Greater bromodeoxyuridine immunostaining in early weaned rats occurred on d 3. Protein and DNA contents were greater in jejunal mucosa of early weaned rats at d 6. Serum corticosterone levels were elevated on d 1 and d 2 after early weaning compared to controls. To explore whether the intake of nonpurified diet played a role, we also compared the induction of jejunal ODC activity in early weaned pups and pups that were food-deprived for 1 d. ODC activity was not greater in the food-deprived group compared to suckling controls while the early weaned group had 6-fold greater activity 1 d after early weaning. Early weaning stimulates jejunal cell proliferation and differentiation. The temporal sequence of increased ODC activity followed by increases in other growth variables suggests that the induction of ODC activity may act as an early marker of intestinal growth during early weaning.