Iontophoretic study of medial septal neurons in the unanesthetized rat

The effects of the iontophoretic applications of glutamate (Glu), gamma-aminobutyric acid (GABA), acetylcholine (ACh) and carbachol (CARB) were studied on neurons located in the medium septal area (MSA) in the unanesthetized rat. In the absence of anesthesia, functional properties of the MSA neurons were significantly different from those observed in the urethane-anesthetized rat (higher variability of discharge rate, lower percentage of rhythmically bursting neurons). Glu excited 80% and GABA inhibited 96% of the MSA neurons. These percentages were similar to those obtained in the urethane-anesthetized rats. In contrast, the percentage of neurons excited by ACh (28%) or by CARB (27.2%) were significantly lower than in the urethane-anesthetized rat. Our results suggest that urethane might alter cholinergic sensitivity in the MSA and confirm that anesthesia can induce a bias in the iontophoretic study of some brain structures.

The urine urokinase concentration in end stage renal disease with acquired renal cyst

To see whether there was any difference in the urine urokinase concentration between acquired cystic kidney disease (ACKD) group and control (non cyst) group in end stage renal disease patients (ESRD), we evaluated fifty ESRD patients who had been maintained on chronic hemodialysis for various period. The urine urokinase concentration was higher in the ACKD group (17.5 +/- 14.7 unit/ml, range 13.5-47.0 unit/ml, n = 9) than the control group (4.1 +/- 3.4 unit/ml, range 0.5-12.0 unit/ml, n = 36) (p less than 0.001), and polycyst group (2.6 +/- 1.8 unit/ml, range 1.0-5.1 unit/ml, n = 5) (p less than 0.01). But there was no difference between the control group and polycyst group. In the control group and the ACKD group, there was a direct relation between the dialysis duration and the urokinase concentration and the longer the dialysis duration, the higher the urine urokinase concentration (r squared = 0.424, p = 0.0001). The hemodialysis duration was longer in the ACKD group (42 +/- 17.0 months) than the control group (20.0 +/- 12.5 months) (p less than 0.005). These findings suggest that urokinase may be responsible for cystogenic degeneration in ESRD.

Specificity, inhibitory studies, and oligosaccharide formation by beta-galactosidase from psychrotrophic Bacillus subtilis KL88

beta-Galactosidase from psychotrophic Bacillus subtilis KL88 was specific to the beta-D-glycosidic linkage normally present in lactose. The enzyme was completely inhibited by transition metal ions (Cu2+, Fe3+, Fe2+, Zn2+) and partially inhibited by high concentrations of glucose and galactose as well as Ca2+. It was activated by most of the alkaline earth metal ions (NA+, K+, Li+). Oligosaccharides were formed at the different levels of lactose concentrations reaching more than 20% for high lactose concentration (20%). Three types of oligosaccharides were formed in significant concentrations detected by HPLC analysis.

Treatment of thoracic multiloculated empyemas with intracavitary urokinase: a prospective study

The authors prospectively treated 10 consecutive patients with multiloculated empyemas with intracavitary instillation of urokinase via a percutaneous drainage catheter. Urokinase (100,000 IU) in 100 mL of 5% dextrose in water was instilled into the pleural cavity via a percutaneous drainage catheter. After overnight clamping, the catheter was opened and the empyema drained with use of negative suction (20 cm H2O). Intermittent irrigation of the catheter with normal saline was performed to prevent clogging of the catheter. Complete drainage of multiloculated empyemas was accomplished in nine patients by means of intracavitary instillation of urokinase via a single 8-F catheter. One patient showed complete drainage of multiloculated empyema, but recurrent empyema appeared in the site of a previous tube thoracostomy. A total of 100,000-700,000 IU (mean, 400,000 IU) of urokinase were needed for complete drainage in all patients. Plasminogen and fibrin degradation product levels in empyema fluid were determined before instillation of urokinase to demonstrate any fibrinolytic action. No complications occurred.

Roles of the highly conserved aspartate and lysine residues in the response regulator of bacterial chemotaxis

The chemotactic responses of bacteria such as Escherichia coli and Salmonella typhimurium are mediated by phosphorylation of the CheY protein. Phospho-CheY interacts with the flagellar motor switch to cause tumbly behavior. CheY belongs to a large family of phosphorylated response regulators that function in bacteria to control motility and regulate gene expression. Residues corresponding to Asp57, Asp13, and Lys109 in CheY are highly conserved among all of these proteins. The site of phosphorylation in CheY is Asp57, and in the three-dimensional structure of CheY the Asp57 carboxylate side chain is in close proximity to the beta-carboxylate of Asp13 and the epsilon-amin of Lys109. To further examine the roles of these residues in response regulator function, each has been mutated to a conservative substitution. Asn for Asp and Arg for Lys. All mutations abolished CheY function in vivo. Whereas the Asp to Asn mutations dramatically reduced levels of CheY phosphorylation, the Lys to Arg mutation had the opposite effect. The high level of phosphorylation in the Lys109 mutant results from a decreased autophosphatase activity as well as a lack of phosphatase stimulation by the phosphatase activating protein, CheZ. Despite its high level of phosphorylation, the Lys109 mutant protein cannot produce tumbly behavior. Thus, Lys109 is required for an event subsequent to phosphorylation. We propose that an interaction between the epsilon-amino of Lys109 and the phosphoryl group at Asp57 is essential for the conformational switch that leads to activation of CheY.

Endobronchial tuberculosis: CT features

We analyzed the CT features of 22 patients with endobronchial tuberculosis (EBTB) showing segmental collapse and/or mas-like infiltrates. The CT findings of involved bronchi were bronchial stenosis with wall thickening or peribronchial cuff of soft tissue (n = 9), bronchial obstruction with peribronchial cuff or soft tissue (n = 7), bronchial involvement with tuberculous lymphadenitis (n = 5), or intraluminal lower density polypoid mass with narrowing (n = 1). Enhancement of the peribronchial cuff following intravenous contrast medium administration was noted in four of seven patients in the bronchial obstruction group. The parenchymal lesions distal to the bronchial lesion were segmental collapse, collapse with multiple low density areas (presumed caseous pneumonia), cavities, and round low density lesion (presumed mucoid impaction distal to an endobronchial obstruction). Ill-defined small nodular densities and larger confluent densities suggesting endobronchially disseminated pulmonary tuberculosis were found in the adjacent lung in 10 patients.

Balloon dilatation of intrahepatic biliary strictures for percutaneous extraction of residual intrahepatic stones

Intrahepatic ductal strictures in cholangiohepatitis present an obstacle to successful removal of retained ductal stones via T-tube tracts. We studied the effectiveness of stricture dilatation for stone removal. Fifteen patients with intrahepatic gallstones retained behind strictures underwent balloon dilatation of their strictures to allow stone extraction. All had prior surgical T-tube placement allowing percutaneous access. Balloon dilatation was successful in reducing or eliminating strictures in 86.7% (13 of 15 patients), and complete stone extraction after the successful dilatation was possible in 76.9% (10 of 13 patients). The reasons for failure were impacted stones and acute ductal angulation which prevented passage of catheters. It is concluded that balloon dilatation of intrahepatic biliary strictures is an effective adjunct for extraction of intrahepatic biliary calculi associated with recurrent pyogenic cholangiohepatitis.

Utility of a Haemonchus contortus/jird (Meriones unguiculatus) model for studying resistance to levamisole

Trichostrongylid nematodes of sheep commonly are identified as exhibiting resistance to levamisole. In vitro assays have been developed to study levamisole resistance for Haemonchus contortus, but no in vivo model has been identified for this species. To determine the utility of a H. contortus/jird (Meriones unguiculatus) model for examining levamisole resistance, immunosuppressed jirds were inoculated with approximately 1,000 exsheathed infective larvae of H. contortus (resistant or susceptible to levamisole), treated per os on day 10 postinoculation (PI) with levamisole hydrochloride or analogs of the drug, and killed on day 13 PI. Stomachs were removed, opened longitudinally, incubated in distilled water at 37 C for 5 hr, fixed in formaldehyde solution, and stored for subsequent microscopic examination. Doses of levamisole and its analogs, which elicited percentage clearances of greater than or equal to 93.5 for the susceptible strain, cleared less than or equal to 68.9% of the resistant worms. These data are consistent with activities for the drugs against wild-type and levamisole-resistant strains of Caenorhabditis elegans. Thus, the H. contortus/jird model provides a useful in vivo tool to study resistance to levamisole and possibly other anthelmintics.

Omental teratoma in an adult: a case report

We recently experienced an omental teratoma in a 34-year-old woman. Ultrasonography (US) revealed a large mass of mixed echogenicity, occupying the entire lower abdomen. Computed tomography showed an inhomogeneous solid and cystic mass in the abdominal cavity containing fat and calcification.

A study of the relationship between childhood nephrotic syndrome and allergic diseases

The incidence of atopic diseases in 206 children with nephrotic syndrome (NS) was studied. Boys with NS had three times higher incidence of bronchial asthma than the general population. There was no difference in the girls. Both boys and girls with NS had about three times more allergic rhinitis and ten times more atopic dermatitis than the general population. In NS patients with associated allergic disease, skin test and allergen-specific IgE antibodies by radioallergosorbent test (RAST) were performed. Most of the patients with dust mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae), egg white, or cow's milk protein-specific antibodies had positive skin tests. One hundred of the 206 children with NS received renal biopsies and serum IgE levels were measured. During the acute nephrotic phase the geometric mean serum IgE levels in minimal change nephrotic syndrome (MCNS), IgM mesangial nephropathy (IgMN), hepatitis B virus-associated membranous nephropathy, and treatment-responsive focal segmental glomerular sclerosis patients were all significantly elevated, in descending order of significance. These high serum IgE levels decreased in remission of NS and elevated again during relapse. The relationship between high serum IgE levels in NS patients and the incidence of allergic diseases showed that one third to one fourth of either IgMN or MCNS patients developed allergic diseases. These results suggest that NS patients had a higher allergic disease incidence. Serum IgE level may serve as one of the prognostic factors. However, an increase in the IgE level may be a reflection of body immunoregulatory imbalance that plays a direct pathogenic role in the occurrence of NS and proteinuria.

Evaluation of systemic hemodynamic effects on post-transplant perfusion to renal allograft

Hemodynamic parameters and post-transplant renal perfusion were evaluated in 24 cadaver kidney transplantation. Cardiac output (CO), systemic vascular resistance (SVR) and mean arterial pressure (MAP), were continuously monitored in each patient via a transesophageal Doppler cardiac output monitor and radial arterial catheter. Seventeen were well perfused (Group 1) after releasing vascular clamps. Six among group 1 presented as the clinical picture of acute tubular necrosis. Seven were poorly perfused (Group 2). Post-anastomotic CO significantly increased in group 1, and decreased in group 2. SVR significantly decreased in group 1, and increased in group 2. MAP were not significantly different between group 1 and 2. Treatments based on hemodynamic derangement were initiated as soon as it was detected. Correction of CO was associated with the improvement of post-anastomotic renal perfusion, while SVR and MAP were not. Among the 7 poorly perfused kidneys, 5 became well perfused before leaving the operating room. The remaining 2 resumed their hemodynamic stability and renal function a few days later after oral captopril was administered. Two among the 6 acute tubular necrosis resumed renal function as long as hemodynamic stability was restored. Our study demonstrates that hemodynamic parameters are parallel to renal perfusion status. Restoration of hemodynamic derangement not only improves renal perfusion but also renal function. It is concluded that hemodynamic instability and graft ischemic time contribute to the variation of post-transplant perfusion to renal allograft. Non-invasive cardiac output monitor is a safe and reliable monitor which we recommend to be used during the operation of kidney transplantation.

Performance analysis of piezoelectric composite plates with consideration of the internal losses

The performance of a 2.3 MHz composite transducer with 1-3 connectivity is analyzed using the transmission line model. The basic transducer parameters, including the attenuation coefficient, are determined from the electrical impedance in the vicinity of the resonance. Using these parameters, the effects of internal losses on round trip insertion loss (RTIL) are investigated. Also, electrical impedance, pulse-echo, and RTIL response are calculated and found to be in good agreement with the experimental data.

Hepatitis B viral markers in pregnant women and newborn infants in Korea

A study of the 5,284 pregnant women who delivered at St. Columban’s Hospital in Mokpo City between April 1, 1985 to June 30, 1987 was conducted to determine the presence of hepatitis B viral (HBV) markers in the mothers and infants and to evaluate their effects. Medical histories, physical examinations, liver function studies and the ELISA test for HBV markers were reviewed. The following results were obtained: 1. Of the 5,284 pregnant women, 448 (8.48%) were positive for HBsAg. Three hundred and thirty four women tested positive for HBsAg; 130 (38.92%) were HBeAg positive, 105 (31.44%) were HBeAg and anti-HBe negative, and 99 (29.64%) were anti-HBe positive. 2. Women positive for HBsAg exhibited a slight increase in toxemia (p<0.1), and no significant difference in postpartum hemorrhage (0.05< p <0.1) and the severity of hyper-emesis. 3. SGPT was significantly higher in HBeAg positive women than in HBeAg negative women (p<0.01), and it was significantly more elevated in both eclamptic and preeclamptic women than in normal pregnant women (p<0.005). 4. The frequency of congenital malformation, spontaneous abortion, infantile death and physiologic jaundice was increased in the newborns of chronic HBV carriers, while women with active hepatitis B experienced more premature births. 5. Mother to infant transmission of HBsAg and HBeAg was high in the HBeAg positive group (18.0%, 42.7%) respectively, but very low in the HBeAg negative group (7.8%, 0.0%). Mother to infant transmission of antibodies was in the order of anti-HBc (95.5%), anti-HBe (91.2%) and anti-HBs (75.0%). The effects of the HBV carrier state in pregnant women included increases in toxemia, postpartum hemorrhage, congenital malformations and premature births, however none of them were statistically significant. There was a significant difference in the elevation of SGPT between toxemic and normal pregnant women, and between HBeAg positive and HBeAg negative carrier women. The mother to infant transmission rate of HBeAg was more frequent than that of HBsAg.

Preserved left ventricular systolic function in clinical congestive heart failure

Although clinical congestive heart failure (CHF) is associated with significant left ventricular (LV) systolic dysfunction, recently it has been recognized that LV diastolic dysfunction also may occur in the absence of abnormal systolic performance. A retrospective study evaluated 23 patients with myocardial infarction and CHF who had undergone multigated blood pool scintigraphy and were found to have normal LV ejection fraction (≥ 50%). Average rapid filling velocity (RFV) and slow filling velocity (SFV) were both significantly reduced in CHF patients (5.1 ± 1.3 unit/s, 2.2 ± 1.4 unit/s respectively) compared with normal control group (3.9 ± 1.2 unit/s, 1.3 ± 0.8 unit/s respectively). Rapid filling time and total diastolic time were also significantly prolonged in CHF patients (p<0.01, p<0.05 respectively). There were no significant changes in heart rate and blood pressure between two groups. Thus, normal systolic LV function is encountered in patients with CHF and it appears to be prudent to evaluate diastolic performance as well for optimal therapeutic strategies for CHF patients.

Alterations in left ventricular diastolic function with doxorubicin therapy

To determine whether impaired diastolic function may be an early sign of doxorubicin cardiotoxicity, a retrospective study was performed in 12 patients who had undergone serial radionuclide angiography and were found to have a left ventricular ejection fraction of 55% or more before doxorubicin (Adriamycin) treatment and during follow-up. Average rapid filling velocity and slow filling velocity were both significantly reduced after doxorubicin treatment. Rapid filling velocity decreased from 5.17 +/- 1.52 to 4.18 +/- 0.96 units/s (p less than 0.01), and slow filling velocity decreased from 2.20 +/- 1.32 to 1.42 +/- 0.62 units/s (p less than 0.05). There were no significant changes in filling volume ratio, total diastolic time or diastolic time ratio. Because a change in left ventricular diastolic function can occur before ejection fraction falls to subnormal levels, diastolic function as well as systolic function should be examined for the early detection of doxorubicin cardiotoxicity. The clinical implications of our observations can only be established by a longer-term prospective analysis of left ventricular function in patients receiving doxorubicin therapy.

Co-carcinogenic effects of several Korean foods on gastric cancer induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats

In study I, 48 ACI and Fisher inbred rats were given MNNG 100 micrograms/ml, with or without 1 per cent or 3 per cent red pepper diet; in study II, 164 Sprague-Dawley rats given MNNG 100 micrograms/ml, with or without 5 per cent or 10 per cent NaCl; in study III, 181 Wistar rats given MNNG 83 micrograms/ml with or without maejoo 10 gm per cent/diet; in study IV, 78 Wistar rats given MNNG 83 micrograms/ml with or without ginseng extract 150 micrograms/ml; in study V, 120 Wistar rats given MNNG 83 micrograms/ml with or without retinyl palmitate 150,000 IU/kg. Except for study II (28 weeks), all rats were fed the diets for 37 weeks and were examined at 38 weeks or 40 weeks. In study I, tumor incidence in rats fed a red pepper diet and MNNG solution were 57 per cent (ACI rats, 1 per cent red pepper) and 63 per cent (Fisher rats, 1 per cent or 3 per cent red pepper) which were higher than control group (44 per cent, 43 per cent); in study II, gastric cancer, 61.9 per cent (10 per cent NaCl-MNNG), 27.3 per cent (control); in study III, gastric cancer, 14.8 per cent (maejoo-MNNG), 24 per cent (control); in study IV, malignant tumor of gastroduodenum, 3.4 per cent (ginseng-MNNG), 32.1 per cent (control); in study V, forestomach papilloma, 10.7 per cent (retinoid-MNNG), 29.4 per cent (control), and cancer in duodenum and small intestine, 50.0 per cent (retinoid-MNNG), 17.6 per cent (control). Thus, gastric carcinogenesis was enhanced by red pepper and a high salt diet, was inhibited by a maejoo and ginseng diet and was not effected by vitamin A.

Artificial siderophores. 2. Syntheses of trihydroxamate analogues of rhodotorulic acid and their biological iron transport capabilities in Escherichia coli

Tris[(acetylhydroxyamino)alkyl] isocyanurates 2a-c were synthesized from alpha, omega-dibromoalkanes 5 in four steps. The alkylation of the bromides 5a-c with O-benzyl-N-[(trichloroethoxy)carbonyl]hydroxylamine in the presence of DBU gave N-alkylation products 7a-c. The (trichloroethoxy)cabronyl protecting group of 7a-c was easily removed by Zn dust in acetic acid. When the reaction was performed with acetic anhydride, the desired N-acetylated materials 10a-c were obtained. The alkylation of cyanuric acid with 12 in the presence of base provided the N-alkylated materials 13, which were hydrogenated to provide 2a-c. In order to determine the affect of structural modifications on biological activity, various chain lengths of the side arms were utilized and the retroanalogue 3 was prepared. Most of the compounds examined acted as ferrichrome in supporting the iron nutrition of Escherichia coli. However, tris[(acetylhydroxyamino)butyl] isocyanurate 2b, and to some extent its pentyl analogue, 2c, displayed the unique and remarkable property of supporting growth of fhuB mutants, the latter unresponsive to the other analogues and to all natural siderophores tested.

Artificial siderophores. 1. Synthesis and microbial iron transport capabilities

Several di- and trihydroxamate analogues of natural microbial iron chelators have been prepared. The syntheses involved linkage of core structural units, including pyridinedicarboxylic acid, benzenetricarboxylic acid, nitrilotriacetic acid, and tricarballylic acid, by amide bonds to 1-amino-omega-(hydroxyamino)alkanes to provide the polyhydroxamates 1-5. The required protected (hydroxyamino)alkanes 8, 16, and 21 were prepared by different routes. 1-Amino-3-[(benzyloxy)amino]propane di-p-toluenesulfonate (8) was prepared from the N-protected aminopropanol 6 by oxidation to the aldehyde, formation of the substituted oxime, and reduction with NaBH3CN followed by deprotection of the Boc group. The pentyl derivatives 16 and 21 were made by direct alkylation with either benzyl acetohydroxamate or N-carbobenzoxy-O-benzylhydroxylamine. In Escherichia coli RW193 most of the analogues behaved nutritionally as ferrichrome. However, in E. coli AN193, a mutant lacking the ferrichrome receptor, capacity to use other natural siderophores was retained while response to all analogues was lost.

Terminals of intralaminar thalamic neurons in the pallidum externum of Saimiri sciureus

Stereotactic coagulations of intralaminar thalamic nuclei in 6 squirrel monkeys Saimiri sciureus produced dark degenerations only of type IV synapses in pallidum externum, according to the classification of Hassler and Chung often preserving the slightly asymmetric contact and subsynaptic densities. Other type IV boutons underwent semidark degeneration, whereas others showed crystalloid degeneration. Some of type IV boutons show the deposition of many dense core vesicles and mitochondria with loss of most synaptic vesicles. Enlarged type IV boutons are sometimes overcrowded with irregularly shaped lysosomes. Thus, a monosynaptic connections of intralaminar thalamic nuclei to pallidum externum could be demonstrated.

Three Systems for Biochemical Characterization of Lactobacilli Associated with Meat Spoilage

Three methods (APIZYM, Minitek and VPI systems) were compared for their ability to characterize some of lactobacillus isolates from anaerobically spoiled meats. Nineteen authentic lactobacillus cultures obtained from various sources were also compared. Greening spoilage isolates from frankfurters were identified as Lactobacillus viridescens by the APIZYM and Minitek tests. Lactobacillus isolates from spoiled veal were identified as Lactobacillus plantarum by one of the three methods. Other isolates which could not be assigned to a generic level appeared to be atypical streptobacteria or betabacteria. Except for some disagreement in the identity of lactobacilli among the three systems, they proved useful in distinguishing between the different lactobacilli.