Hemolytic-uremic syndrome in a six-year-old girl after a urinary tract infection with Shiga-toxin-producing Escherichia coli O103:H2.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to H H Kim.
Explore the source record for details and available documents.
We determined the effect of breathing cold dry air (-39 degrees C, 0.1% relative humidity, RH) and warm humid air (43 degrees C, 100% RH) on airway mucosal blood flow (Qaw) in normal human subjects (n = 8, age 25-53 years) at rest. Qaw was measured with a dimethylether uptake technique which reflects blood flow in the mucosa of large airways corresponding to a 50 ml anatomical dead-space segment extending distally from the trachea. Mean Qaw was 10.1 +/- 1.9 ml min-1 (mean +/- S.D.) during room air breathing (25 degrees C, 70% RH) and decreased to 4.7 +/- 2.1 ml min-1 during cold dry air breathing (p < 0.05). Within 20 min of resuming room air breathing, mean Qaw had returned to baseline. Breathing warm humid air had no significant effect on mean Qaw (8.2 +/- 1.4 ml min-1). These results indicate that quiet breathing of frigid air causes vasoconstriction in central airways.
The authors encountered two cases of gastrointestinal complication caused by ingested magnetic beads. Because of the magnetic property, the steel beads, components of bracelets or necklaces worn for naturalistic healing power, have caused perforations, fistula formation, and obstruction. The authors believe the public should be warned of the health hazard of such devices.
To determine the factors influencing stone fragmentation and to suggest when to change treatment modality for ureteral calculi refractory to repetitive in situ extracorporeal shockwave lithotripsy (SWL), we analyzed 369 patients treated primarily by the second-generation lithotripter, Siemens Lithostar, from March 1989 to December 1993. Three hundred forty-two (92.7%) of the patients were ultimately free of stones after repetitive in situ SWL. The cumulative stone-free rates of the first, second, and third session were 64%, 81%, and 88%, respectively, and the increment in the cumulative stone-free rate thereafter with further repeated in situ SWL was minimal (p < 0.01). The cumulative stone-free rate at the third session was 89%, 87%, and 86% for proximal, middle, and lower ureteral stones, respectively (p > 0.05). The cumulative stone-free rate at the third session was 100%, 90%, 87%, 70%, 67%, and 50% for stones <5 mm, 6 to 10 mm, 11 to 15 mm, 16 to 20 mm, 21 to 25 mm, and >25 mm, respectively (p < 0.001). According to the radiopacity of the stone, the cumulative stone-free rate at the third session was 96% for stones with minimal opacity, 94% for those with moderate opacity, and 70% for highly opaque stones (p < 0.001). The cumulative stone-free rate at the second session was 100% without ureteral obstruction; 80% with mild, 57% with moderate, and 67% with severe obstruction; and 50% in patients with nonappearance of the kidney (p < 0.05). From these observations, it could be concluded that the factors influencing fragmentation were the size and radiopacity of the calculi and the degree of ureteral obstruction, whereas the location of the calculi did not influence the cumulative stone-free rate of repetitive in situ SWL. It is preferable to restrict in situ SWL to three sessions in patients with ureteral calculi refractory to shockwaves. An early change of treatment modality either to ureteroscopic manipulation or to open surgery would be recommended if there were risk factors as listed above.
We retrospectively analyzed night-to-night variability in the indices of sleep apnea in a group of men who underwent consecutive polysomnograms (PSGs) in the evaluation of impotence. The study group consisted of 37 subjects. Fifty-seven percent of the subjects had an apnea/hypopnea index (AHI) of 5 or more on the first PSG, whereas 70% met this criterion on the second study. On both PSGs, 49% of the subjects exhibited an AHI of 10 or more. The AHI varied by 10 or more between the two PSGs in 32% of the cases. Using a threshold AHI of 5 or more to establish a diagnosis of sleep apnea, 22% of the subjects would not have been diagnosed by the first PSG, and the negative rate for the first PSG was 50%. The variability observed in the AHI could not be explained by differences in total sleep time; sleep stages [1 through 4 and rapid eye movement (REM) sleep]; the amount of time sleeping supine, or a combination of sleep stage and position. The mean AHI, the apnea/hypopnea-related nadir, and the mean oxyhemoglobin saturation did not differ among the two PSGs. Our observations support the notion that for groups of subjects the mean AHI is relatively constant across 2 nights of study in the sleep laboratory. However, when an AHI of 5 or 10 or more is the sole criterion used to establish the diagnosis of sleep apnea, a single PSG may not be sufficient to rule out the presence of a sleep apnea syndrome.
The purpose of this study was to determine the effect of hyperventilation (40 L/min) with room air (25 degrees C; 70% relative humidity) and frigid air (-10 degrees C; 0% relative humidity) on airway mucosal blood flow (Qaw) in normal subjects (n = 7; 26 to 54 yr of age). Qaw was measured with the dimethyl ether uptake technique, which reflects blood flow in the mucosa of large airways corresponding to a 50-ml anatomic dead space segment extending distally from the trachea. Mean (+/- SE) baseline Qaw during quiet (room air) breathing was 6.6 +/- 0.6 ml/min (range, 3.9 to 10.9). Qaw failed to change significantly during and after eucapnic hyperventilation with room air (thermal stress, 224 cal/min). In contrast, eucapnic hyperventilation with frigid air (thermal stress, 720 cal/min) increased Qaw in every subject, with the peak value occurring either during or over a 30-min period after hyperventilation; by 60 min, Qaw had returned toward baseline. The mean maximal Qaw was 310 +/- 49% of baseline (p < 0.05). Neither type of hyperventilation had an effect on airway resistance. We conclude that in normal subjects, Qaw increases during and/or after eucapnic hyperventilation with frigid air, and that this response is related to the magnitude of the thermal stress rather than to the level of ventilation.
Three cDNA fragments that encoded all but the extreme N terminus of the rat ErbB3 protein were cloned by low-stringency screening of a rat liver cDNA library with a human ERBB3 probe. The remaining 5'-end of the cDNA was generated by a reverse transcription-polymerase chain reaction method, and a single full-length rat ErbB3 cDNA was assembled. A comparison of the deduced amino acid (aa) sequences of human and rat ErbB3 was made, and the effects of certain aa substitutions in the putative protein tyrosine kinase domain were considered. The rat ErbB3 cDNA was subsequently expressed in cultured NIH-3T3 mouse fibroblasts, in which a high level of approx. 180-kDa recombinant ErbB3 (re-ErbB3) was generated. The rat re-ErbB3 produced in transfected fibroblasts was responsive to the polypeptide, heregulin, a known ligand for ErbB3. Challenge of transfected fibroblasts with heregulin stimulated the phosphorylation of rat re-ErbB3 on Tyr residues and promoted its association with the p85 subunit of phosphatidylinositol 3-kinase. Together, these results indicate that a fully functional rat ErbB3 cDNA has been isolated, and that fibroblast cells expressing this cDNA will be suitable for investigations of the signal transduction mechanism of ErbB3.
We have reported that overexpression of Neu leads to heregulin-stimulated neurite outgrowth and the tyrosine-phosphorylation of Neu and other cellular proteins in PC12 cells. Considering that Neu/ErbB2 alone is not able to functionally couple to heregulin, we looked for the possible involvement of ErbB3 in these neurite outgrowth and tyrosine phosphorylation responses. We found that heregulin stimulates the tyrosine phosphorylation of endogenous ErbB3 protein in PC12 cells and that this phosphorylation, like that of Neu, is greatly enhanced in cells that overexpress Neu. Furthermore, overexpression of ErbB3 in PC12 cells led to heregulin-stimulated neurite extension. In addition to becoming tyrosine-phosphorylated, Neu/ErbB2 and ErbB3 associate with each other, and each associates with the 85-kDa regulatory subunit (p85) of phosphatidylinositol 3-kinase in a heregulin-dependent manner. Thus, Neu/ErbB2 and ErbB3 appear to cooperate to mediate the heregulin signal in PC12 cells. Like heregulin, epidermal growth factor (EGF) also stimulate the tyrosine phosphorylation of both Neu and ErbB3. However, there are clear differences between the EGF- and heregulin-stimulated phosphorylations of ErbB3. In the heregulin response, two tyrosine-phosphorylated forms of ErbB3 are detected. Of these, only the more quickly migrating form (on SDS-polyacrylamide gel electrophoresis) is found to be associated with Neu, whereas the other, more slowly migrating form is uniquely capable of forming stable complexes with p85. In the EGF response, at least two tyrosine-phosphorylated forms of ErbB3 are detected, but these phosphoproteins have distinctly lower apparent molecular weights compared with the heregulin-stimulated ErbB3 phosphoproteins and do not complex with p85. Thus the formation of a stable ErbB3-p85 complex in PC12 cells is a unique outcome of heregulin signaling that correlates with the differences in cell morphology induced by the activated EGF receptor and the Neu tyrosine kinase.
The isozyme form of eukaryotic initiation factor 4F [eIF-(iso)4F] from wheat germ is composed of a p28 subunit that binds the 7-methylguanine cap of mRNA and a p86 subunit having unknown function. The p86 subunit was found to have limited sequence similarity to a kinesin-like protein encoded by the katA gene of Arabidopsis thaliana. Native wheat germ eIF-(iso)4F and bacterially expressed p86 subunit and p86-p28 complex bound to taxol-stabilized maize microtubules (MTs) in vitro. Binding saturation occurred at 1 mol of p86 per 5-6 mol of polymerized tubulin dimer, demonstrating a substoichiometric interaction of p86 with MTs. No evidence was found for a direct interaction of the p28 subunit with MTs. Unlike kinesin, cosedimentation of eIF-(iso)4F with MTs was neither reduced by MgATP nor enhanced by adenosine 5'-[gamma-imido]triphosphate. Both p86 subunit and p86-p28 complex induced the bundling of MTs in vitro. The p86 subunit was immunolocalized to the cytosol in root maize cells and existed in three forms: fine particles, coarse particles, and linear patches. Many coarse particles and linear patches were colocalized or closely associated with cortical MT bundles in interphase cells. The results indicate that the p86 subunit of eIF-(iso)4F is a MT-associated protein that may simultaneously link the translational machinery to the cytoskeleton and regulate MT disposition in plant cells.
The purpose of this study is to evaluate the MR findings of gestational trophoblastic tumors (GTTs). Ten patients who confirmed the diagnosis (4 choriocarcinomas and 6 invasive moles) constituted the basis of our study. The MR findings from these patients were prospectively correlated with the histopathology of resected tumor specimens. MR findings of 4 patients with choriocarcinomas were well-defined, hemorrhagic masses with central necrosis. In contrast, 6 patients with invasive moles showed ill-defined, permeative masses with densely enhanced solid components and tiny cystic lesions. The trophoblastic proliferation, coagulation necrosis, and molar villi had varying signal intensities on T1- and T2-weighted images. Our results suggest that MR imaging is a promising tool for noninvasive morphologic analysis of GTTs.
A three factorial designed feeding experiment with common carp (Cyprinus carpio L.) was carried out in an intensive experimental rearing system. Fish (initial body weight 200 g) were fed on two different levels of dietary energy (16 and 18 MJ DE/kg DM), two different levels of protein (320 and 420 g CP/kg DM) and also two different feeding intensities (100% and 75% of the maximum intake). The experiment was terminated when fish reached a mean body weight of 1300 g. Growth, feed utilization and nutrient composition of the whole body and fillet were observed. The highest growth was obtained when the fish were fed on the diet containing high dietary energy and high dietary protein with satiation feeding. High dietary energy, high dietary protein and restriction of feed intake improved feed conversion ratios. High dietary energy, low dietary protein and restrictive feeding increased energy utilization. Low dietary protein and restrictive feeding resulted in better protein utilization. Fish fed with high dietary energy contained more fat and less protein in their carcasses. A lower fat content but higher protein and higher ash content in fish carcasses was shown when fish were fed with a diet high in protein and fed restrictively.
OBJECTIVE: Krukenberg's tumors are metastatic tumors of the ovary. Some of these tumors had hypointense solid components on T2-weighted MR images. The purpose of this study was to evaluate the MR features of Krukenberg's tumors and to compare them with those of other solid ovarian tumors to determine whether hypointense solid components on MR images were characteristic of Krukenberg's tumors. MATERIALS AND METHODS: Twelve patients with 21 surgically proven Krukenberg's tumors of the ovary were included in the study; the tumors were bilateral in nine and unilateral in three. The MR images were studied to determine the morphologic characteristics and signal intensity patterns of the tumors (especially the presence or absence of hypointense solid components on T2-weighted images and isointense components on T1-weighted images). MR findings were correlated with histopathologic results. The MR features of 26 additional benign or malignant solid primary ovarian tumors were reviewed for comparison. RESULTS: Of the 21 Krukenberg's tumors, 14 were mostly solid and seven were entirely cystic or mostly cystic on MR images. All had sharp margins, and the oval configuration was preserved in 16. Twelve (57%) of the 21 tumors showed various amounts of hypointense solid components in random distribution or predominantly in the periphery on MR images; pathologically, these components corresponded to areas of dense collagenous stroma. MR imaging also showed that the cystic components within the masses had either well-defined or ill-defined borders. Multiseptation was noted in two masses. Of the 26 additional primary ovarian tumors, only three showed hypointense solid components on MR images. These included thecoma, fibrothecoma, and poorly differentiated adenocarcinoma. CONCLUSION: Our findings suggest that identification of hypointense solid components within an ovarian mass on T2-weighted MR images is a characteristic, although not specific, finding for Krukenberg's tumors, especially when the tumors are bilateral, have sharp margins, and have an oval configuration.
Milk fat globule membrane proteins in washed cream were analyzed using preparative isoelectric focusing followed by SDS-PAGE. Five major protein bands of milk fat globule membrane were observed with apparent molecular mass of 150, 67, 62.5, 51, and 49 kDa. The protein of band 5 (49 kDa) was well separated from the protein of band 4 (51 kDa). Heat-induced effects (72 and 87 degrees C for 2.5, 5, 10, 20, 30, and 60 min) on whole milk proteins were also investigated under nonreducing and reducing conditions to study disulfide interactions between serum proteins and those in the fat membrane. beta-Lactoglobulin and other milk serum proteins interacted readily with milk fat globule membrane and membrane proteins at 87 degrees C, but only slightly at 72 degrees C. However, the interactions between serum proteins and fat globule membrane proteins cannot be explained solely by disulfide linkage formation. Some membrane proteins, especially the 49-kDa protein (band 5), underwent drastic changes after heat treatment. Further characterization of the 49-kDa protein demonstrated that it binds concanavalin A; AA composition and N-terminal sequence of the protein were determined and compared with those reported in the literature.
UNLABELLED: PURPOSE AND MATERIAL AND METHODS: MR findings of 9 surgically proven tubo-ovarian abscesses were analyzed in 8 patients. The images were evaluated for signal intensity characteristics and morphologic appearance of the mass, and presence of secondary changes in adjacent pelvic organs and structures. RESULTS: The signal intensity of the lesions on T1-weighted images was hypointense to the surrounding muscle and myometrium in 5 patients, isointense in 3 and hyperintense in 1. On T2-weighted images the signal intensity was hyperintense (n = 6) or heterogeneous (n = 3). A thin rim (1-3 mm) with hyperintensity on T1-weighted images was noted in the innermost aspect of the masses. Other findings were ill-defined margin, thickened wall, multiple internal septa, shading and gas collection. "Mesh-like" linear strands were noted in the pelvis in all patients, with involvement of adjacent pelvic organs in 7 and lymphadenopathy in 3. CONCLUSIONS: In this limited number of cases MR imaging showed great potential for demonstrating the extent of the disease, characterizing the lesions and making a specific diagnosis.
The ErbB3 protein is a member of the ErbB subfamily of receptor protein tyrosine kinases. In the present study, the mechanism by which the ErbB3 protein is phosphorylated and the signal-transducing functions of this phosphorylated protein were investigated. When phosphorylated by the epidermal growth factor receptor in vitro, the ErbB3 protein strongly associated with the regulatory p85 subunit and the catalytic activity of phosphatidylinositol (PI) 3-kinase. The association of PI 3-kinase with ErbB3 in human breast cancer cells was found to be correlated with the constitutive phosphorylation of ErbB3 on tyrosine residues. In MDA-MB-468 breast cancer cells in which the ErbB3 protein is not constitutively phosphorylated, stimulation with epidermal growth factor led to the phosphorylation of ErbB3 on tyrosine residues and the formation of a functional signal transduction complex involving the ErbB3 protein and PI 3-kinase. These results suggest that the ErbB3 protein can be phosphorylated on tyrosine residues by a cross-phosphorylation mechanism and that the phosphorylated ErbB3 protein can couple other growth factor receptor protein tyrosine kinases to the PI 3-kinase pathway in a manner similar to the insulin receptor substrate 1 protein.
The resistance of Escherichia coli O157:H7 to amoxicillin/clavulanic acid, ampicillin, ceftazidime, ceftriaxone, cefuroxime, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, streptomycin, sulfisoxazole, tetracycline, ticarcillin, tobramycin, and trimethoprim-sulfamethoxazole was examined, and resistant strains were characterized. All 56 isolates collected between 1984 and 1987 were susceptible to all antibiotics tested; 13 (7.4%) of 176 strains isolated between 1989 and 1991 were resistant to streptomycin, sulfisoxazole, and tetracycline. lambda-restriction fragment length polymorphism analysis suggested that the 13 resistant strains belonged to nine different clones. The emerging resistance of E. coli O157:H7 to antibiotics could portend an increased prevalence of this pathogen in food animals that receive antibiotics. Antimicrobial resistance of E. coli O157:H7 could be useful as a rapid epidemiologic marker and as a way to select this pathogen from suspected vehicles of transmission, but this resistance could also complicate therapeutic trials with sulfa-containing antibiotics.
Esophageal perforation and acquired tracheoesophageal fistulae (ATEF) are rare sequelae of foreign body ingestion in the pediatric population. Here we discuss the cases of two patients with esophageal perforation caused by prolonged impaction of a coin; in one case, a tracheoesophageal fistula developed. The presence of aerodigestive symptoms and signs in infants and small children should prompt physicians to consider foreign body ingestion and the presence of an ATEF. Clinical presentation, diagnostic modalities, and technical considerations for surgical management are outlined.
A study was performed to evaluate whether kidney-preserving surgery would be appropriate or not, and in the affirmative for which indications. Eighty-one kidneys removed at Seoul National University Hospital between January 1987 and June 1991 were serially cut into 5-mm slices to probe for any small renal lesions. Of the 81 kidneys, 15 (18.5%) renal units contained 39 satellite nodules with histological patterns identical to the primary tumor. The number of satellite nodules was 2.6 per kidney (range 1-6). The size of the satellite nodules ranged from 0.5 to 2 cm (mean 0.9 cm). The presence of satellite nodules increased with increasing T stage and size of the primary tumor (p < 0.05 by Fisher's exact test). The presence of satellite nodules was significantly different between kidneys with primary tumors larger than 7 cm and less than 7 cm (p < 0.05 by the chi 2 test). Especially, no satellite nodules were found in 23 kidneys whose primary tumors were less than 5 cm. These observations suggest that kidney-preserving surgery could be a valuable treatment option for small localized renal cell carcinoma not only in patients with a single kidney or deteriorated contralateral kidney function but also in patients with normal contralateral kidneys, especially when the size of the tumor is less than 5 cm.