PubMed Health⌕ Search

Biomedical subjects

W K Jung

Publications and source records attributed to W K Jung.

At least 19 recordsLinked to original sources

Application of extended single-reaction multiplex polymerase chain reaction for toxin typing of Staphylococcus aureus isolates in South Korea.

The extended single-reaction multiplex PCR (esr-mPCR) developed in this study to detect staphylococcal enterotoxins (SEs), including SEA, SEB, SEC, SED, SEE, SEH, SEI, and SEJ, requires fewer sets of primers than other conventional multiplex PCRs and can be used to detect newly identified staphylococcal enterotoxins SEs more readily. Esr-mPCR analysis of 141 isolates of Staphylococcus aureus obtained from abattoir and livestock product samples revealed that 27 of the S. aureus isolates were toxigenic, and two were 2 multitoxigenic isolates. The most prevalent SE type was SEI followed by SEA and SEH. In addition, we investigated the clonal relatedness of toxigenic S. aureus isolates by arbitrarily primed PCR (AP-PCR). AP-PCR analysis of toxigenic S. aureus isolates revealed that the discriminatory power of AP-PCR was 9 (D=0.81), 8 (D=0.77), and 10 types (D=0.83) with primers AP1, ERIC2, and AP7, respectively. The combination of three each AP-PCR result could rearrange toxigenic S. aureus isolates into 10 types and five subtypes, with the D-value of 0.92. Interestingly, our data showed that toxigenic S. aureus isolates from different sources had different fingerprinting patterns although some of them carried the same types of SE genes. These data suggest that combinations of esr-mPCR and AP-PCR can provide a powerful approach for epidemiological investigation of toxigenic S. aureus isolates.

Abattoirs↗

Comparison of survival probabilities for living-unrelated versus cadaveric renal transplant recipients.

UNLABELLED: Any attempt to improve organ donation would be of benefit due to the growing shortage of cadaveric sources for transplantation. OBJECTIVE: We compared the graft survivals and possible predictive variables among renal transplant recipients with organs from living unrelated (LURD) versus cadaveric donors (CD). METHOD: Among 104 consecutive renal transplants performed from July 1992 to February 2003, 41 were from LURD and 24 from CD. Immunosuppressive regimens were based on cyclosporine and steroids with mycophenolate mofetil added after 1998. Patient and graft survivals were estimated using the Kaplan-Meier method and compared using log-rank tests. The significance level of predictive variables was analyzed with the Cox proportional hazard model. The follow-up period was 2 to 127 months (median 46 months). RESULTS: Eight recipients lost their grafts (six from LURD and two from CD) due to four chronic rejections, one acute rejection, one recurrence of primary disease, and one death with a functioning graft. The graft survival rates at 1, 3, 5, and 7 years were 97.6%, 91.9%, 88.5%, and 82.2% for LURD transplants versus 95.5%, 90.9%, 90.9%, and 90.9% for CD transplants, respectively (P > .05). Delayed graft function and donor age (>55 years old) were statistically significant predictors of graft survival among LURD transplants. Donor age (>55 years old) and multiple preoperative transfusion history were significant in CD transplants. CONCLUSION: LURD transplant survival was similar to that of CD transplants in our series. LURDs are an excellent source of organs to expand the donor pool.

Actuarial Analysis↗

Risk factors on graft survival of living donor kidney transplantation.

UNLABELLED: Living donors have always been the basic resources of transplantation in our country, where cadaveric harvesting is still hampered for various reasons. OBJECTIVE: The aim of this study was to compare graft survival rates between living unrelated donor (LURD) and living related donor (LRD), to assess the potential risk factors for the graft survival, and to discuss the role of LURD. METHOD: From October 1991 to February 2003, 77 living donor renal transplants were performed: 41 were LURD and 36 were LRD transplants. The analyzed variables were donor relationship, recipient age and sex, donor age and sex, HLA-DR mismatching, nonspecific blood transfusion history of donor, acute rejection episodes, repeated rejection episode (more than 3 times), delayed graft function, recurred primary disease, and immunosuppressive regimen. Graft survival rate was assessed with the Kaplan-Meier method and the significance of possible variables with the Cox proportional hazard model. RESULTS: Eleven recipients lost their grafts (6 from LURD and 5 from LRD), most of them are due to chronic rejection (n = 7). Overall 3-, 5- and 10-year graft survival in live donors were 92.8%, 86.6%, and 76.9%, respectively. Graft survival at 3, 5, and 10 years being 91.9%, 88.5%, and 74.7% for the LURD versus 94%, 84%, and 78.8% for LRD transplants (P > .05). Acute rejection episodes, especially more than 3 times (risk ratio [RR] = 11.1) and preoperative multiple transfusion history (RR = 4.2) were significant factors on graft survival in our series. CONCLUSION: Acute rejection episodes markedly decreased the long-term graft survival in live donor renal transplants. The use of LURD transplants provides graft survival comparable with LRD transplants and proper management to acute rejection is essential for long-term graft survival.

Adult↗

Antimicrobial performance of alkaline ionic fluid (GC-100X) and its ability to remove Escherichia coli O157:H7 from the surface of tomatoes.

An efficacy test of GC-100X, a noncorrosive alkaline ionic fluid (pH 12) composed of free radicals and supplemented with xylitol, was carried out against six major foodborne pathogens-Staphylococcus aureus FRI 913, Salmonella enterica serovar Enteritidis ATCC 13076, S. enterica serovar Typhimurium DT104 Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894, and Pseudomonas aeruginosa KCTC 1637-at three different temperatures (4, 25, and 36 degrees C) with or without organic load (2% yeast extract). Results revealed a more than 4-log10 (CFU/ml) reduction (1.0 x 10(4) CFU/ml reduction) against all pathogens reacted at 37 degrees C for 3 h in the absence of organic material. GC-100X solution diluted with an equal volume of distilled or standard hard water (300 ppm CaCO3) showed effective bactericidal activity, particularly against gram-negative bacteria. Washing efficacy of GC-100X solution was compared against E. coli O157:H7 on cherry tomato surfaces with those of a commercially used detergent and chlorine water (100 ppm). Viable cell counts of E. coli O157:H7 that had penetrated to the cores of tomatoes after sanitizing treatment revealed that GC-100X stock and its 5% diluted solutions had similar washing effects to 100-ppm chlorine water and were more effective than the other kitchen detergent. These results indicate that GC-100X has good bactericidal and sanitizing activities and is useful as a new sanitizer for food safety and kitchen hygiene.

Chlorine↗

[Patient surgical masks during regional anesthesia. Hygenic necessity or dispensable ritual?].

OBJECTIVE: The use of surgical face masks (SFM) is believed to minimize the transmission of oro- and nasopharyngeal bacteria to wounds and surgical instruments. However, there are disadvantages for patients undergoing regional anaesthesia and wearing masks: deficient assessment of lip cyanosis, anxiety, retention of CO2, costs. Up to now no studies have been published investigating whether or not SFMs, worn by patients during regional anaesthesia, will reduce bacterial convection. METHODS: We investigated 72 patients during aseptic operations: 24 individuals with regional anaesthesia and SFMs, 22 individuals with regional anaesthesia without SFMs and 26 patients undergoing general anaesthesia. Using an air sampler (volumetric impaction method) 100 L air were collected on blood agar over 2 min. After incubation at 37 degrees C over 60 h the colony forming units (CFU) were counted and differentiated. Airborne culturable bacteria were sampled over the operation field, on the anaesthetic side of the surgical curtain, as well as 10 cm before and to the side of the patients mouth. RESULTS: At all 4 locations there were no significant differences in the number of CFUs between patients wearing a SFM or not (e.g. over the operation field: patient with SFM 5.5 +/- 1.1; no SFM 4.8 +/- 1.2; mean +/- SEM). Significantly more CFUs were detected in patients undergoing general anaesthesia (p < or = 0.05). The extent of the operation did not correlate with the number of CFUs; however, we observed a trend that more CFUs were detected with an increasing number of persons working in the operating room. CONCLUSION: Surgical face masks worn by patients during regional anaesthesia, did not reduce the concentration of airborne bacteria over the operation field in our study. Thus they are dispensable. A higher airborne germ concentration has been detected in patients during general anaesthesia. The reasons for this finding are unknown, but it may be discussed as being a result of a higher activity and number of staff involved during general anaesthesia causing more air turbulence.

Adult↗

Bacterial anterior chamber contamination with foldable silicone lens implantation using a forceps and an injector.

PURPOSE: To compare the rate of anterior chamber (AC) contamination during implantation of a foldable three-piece silicone lens using a forceps and an injector. SETTING: Department of Ophthalmology, University of Saarland, Homburg (Saar), Germany. METHODS: In a prospective, randomized study, we cultured AC aspirates of patients who had phacoemulsification with silicone lens implantation through a 3.5 mm temporal clear corneal incision. In Group A, the lens was implanted with a forceps and in Group B, with an injector. Immediately after lens implantation, the AC aspirate (0.05 to 0.10 ml) was collected and sent to the microbiology department. All cultures were incubated for 3 days. As a topical antibiotic, gentamicin was given preoperatively and intraoperatively. RESULTS: One hundred patients (50 in each group) were examined. In each group the bacterial contamination of the AC was 2%. CONCLUSION: Bacterial contamination of the AC was not significantly different after silicone lens implantation with a forceps and with an injector.

Aged↗

Bacteria- and endotoxin-free dialysis fluid for use in chronic hemodialysis.

As the quality of water in the dialysis fluid varies considerably, dialysis fluid is contaminated with a high percentage of bacteria and endotoxins. The bacterial populations contained in the dialysis fluid are as heterogeneous as the chemical structure of the endotoxins that result. The latter can pass through the dialysis membrane whereby high-flux membranes permit a larger number of retransportable molecules than low-flux membranes. A central aim toward a future, safe dialysis process should, therefore, be the production of a dialysate that is free of bacteria and endotoxins. As we were able to demonstrate in various examinations, this goal is most likely to be achieved with the aid of sterile filtration using hollow fiber modules of polyamid. To avoid disinfection of the polyamid membrane, as this would only reach bacteria but not endotoxins, the filter was changed after at most 10 h. The achieved dialysis fluid was free of bacteria and endotoxins. We were also able to show that the release of interleukin-1 was reduced. In addition, side-effects, such as a drop in blood pressure, headaches, muscular cramps, and nausea, were reduced.

Bacteria↗

The arterial switch operation in transposition of the great arteries: anatomic indications and contraindications.

1. The arterial switch procedure is now the operation of choice for typical D-transposition of the great arteries at The Children's Hospital, Boston, USA, the operative mortality rate since 1985 being 3%. 2. There are many anatomic considerations suggesting the morphologically left ventricle (LV) may well be a better systemic pump than the morphologically right ventricle (RV) which, if true, would favor the arterial switch procedure as opposed to an atrial switch operation: (1) The LV consists almost entirely of the sinus or pumping portion, and has only a minimal distal infundibular (conal) component. The RV, by contrast, has a relatively much larger infundibular component, the primary function of which is to prevent regurgitation rather than to pump. (2) Phylogenetically, the LV is the ancient "professional" pump. By contrast, the RV is a comparatively recent modification of the bulbus cordis. (3) The LV is a two-coronary ventricle, whereas the RV is a one-coronary ventricle. (4) The LV has relatively much more compact myocardium (stratum compactum) than does the RV. (5) The mitral valve leaflets are better designed to occlude a circular systemic atrioventricular orifice than are the tricuspid valve leaflets. (6) The papillary muscles of the LV are large, paired, well balanced, and both arise from the same ventricular wall--the LV free wall. By contrast, the papillary muscles of the RV are comparatively small, numerous, unbalanced, and arise from both ventricular septal and free walls. Hence, dilatation of the LV does not pull the LV papillary muscles apart, whereas dilatation of the RV does pull the RV muscles apart, favoring the development or exacerbation of tricuspid regurgitation. (7) The LV has two conduction system radiations, whereas the RV has only one. 3. The current anatomic contraindications to the arterial switch operation in typical D-TGA include the following: (1) an unprepared LV; (2) an aortic intramural left coronary artery arising from the right coronary sinus of Valsalva; (3) pulmonary outflow tract stenosis (with small annulus and subvalvar obstruction) or atresia; (4) aortic outflow tract stenosis (with small annulus and subvalvar obstruction) with tubular hypoplasia of the aortic arch and preductal coarctation; (5) tricuspid or mitral atresia; (6) marked underdevelopment or absence of either the RV sinus or the LV sinus; and; (7) 2 major anomaly of the systemic and/or pulmonary veins, as in the heterotaxy syndrome with asplenia.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Staphylococcus epidermidis induces complement activation, tumor necrosis factor and interleukin-1, a shock-like state and tissue injury in rabbits without endotoxemia. Comparison to Escherichia coli.

Tumor necrosis factor (TNF) and IL-1 are thought to mediate many of the pathophysiologic changes of endotoxemia and Gram-negative bacteremia. In these studies, heat-killed Staphylococcus epidermidis were infused into rabbits to determine whether an endotoxin (LPS)-free microorganism also elicits cytokinemia and the physiologic abnormalities seen in Gram-negative bacteremia. S. epidermidis induced complement activation, circulating TNF and IL-1, and hypotension to the same degree as did one-twentieth the number of heat-killed Escherichia coli. Circulating IL-1 beta levels had a greater correlation coefficient (r = 0.81, P less than 0.001) with the degree of hypotension than TNF levels (r = 0.48, P less than 0.02). Leukopenia, thrombocytopenia, diffuse pulmonary capillary aggregation of neutrophils, and hepatic necrosis with neutrophil infiltration were observed to the same extent after either S. epidermidis or E. coli infusion. However, S. epidermidis infusion did not induce significant (less than 60 pg/ml) endotoxemia, whereas E. coli infusion resulted in high (11,000 pg/ml) serum endotoxin levels. S. epidermidis, E. coli, LPS, or S. epidermidis-derived lipoteichoic acid (LTA) induced TNF and IL-1 from blood mononuclear cells in vitro. E. coli organisms and LPS were at least 100-fold more potent than S. epidermidis or LTA. Thus, a shock-like state with similar levels of complement activation as well as circulating levels of IL-1 and TNF were observed following either S. epidermidis or E. coli. These data provide further evidence that host factors such as IL-1 and TNF are common mediators of the septic shock syndrome regardless of the organism.

Animals↗

Sterile and endotoxin free dialysis fluid for hemodialysis.

As the quality of water in dialysis fluid varies considerably, and, in view of the fact that endotoxin or active derivates can cause acute and chronic side effects in patients under hemodialysis treatment, the dialysis fluid must be sterile and endotoxin-free. The predialyzer fluid in 20 hemodialysis patients was investigated. The bacterial loading was between 5/ml and 12,000/ml, the endotoxin concentration was high and extremely variable. Therefore we introduced the ultrafiltration of the dialysis fluid by a polyamide hollow fiber membrane before entering the dialyzer. All samples were free of bacteria, and the concentration of endotoxin was lower than the detectable limit. With this procedure we can obtain sterile dialysis fluid, which is endotoxin free. Our preliminary results showed that Interleukin-1 in the patients was significantly (p less than 0.005) lower under ultrafiltration of the dialysis fluid than without ultrafiltration.

Colony Count, Microbial↗

Ultrafiltration of dialysis fluid to obtain a sterile solution during hemodialysis.

As the quality of water in the dialysis fluid varies considerably, and in view of the fact that endotoxin or active derivates can cause acute and chronic side effects in patients under chronic hemodialysis treatment, the dialysis fluid must be sterile and endotoxin free. The predialyzer fluid in 20 hemodialysis patients was investigated. The bacterial load was between 5/ml and 12,000/ml, the endotoxin concentration was high and extremely variable. Therefore, we introduced the ultrafiltration of the dialysis fluid by a polyamide hollow fiber membrane before entering the dialyzer. All samples were free of bacteria, and the concentration of endotoxin was lower than the detectable limit. With this procedure, we can obtain sterile dialysis fluid, which is endotoxin free. Our preliminary results showed that interleukin-1 in the patients was significantly (p less than 0.005) lower under ultrafiltration of the dialysis fluid than without ultrafiltration.

Bacteria↗

Kinetic experiments with radionuclides concerning the perilymph-blood barrier in a guinea pig model.

Since 1950 many animal radiotracer experiments have been performed to study inner ear kinetics. For the most part in these studies, radionuclides were applied systemically, following which a discontinuous probing of inner ear fluids or of inner ear tissues was done. Two techniques have been developed in the Section for Experimental Otorhinolaryngology of the University of Würzburg. These have been adapted to the direct and continuous measurements of inner ear efflux kinetics for several hour periods. For this purpose, only a tiny amount of radiotracer need be applied directly to the inner ear. Experiments were done on the anesthetized guinea pig as an animal model. In the first technique, a collimator-detector system is focused precisely on the cochlea, which had been quickly resealed after application of the radionuclide bolus via two small holes in the basal turn of the cochlea. The second technique makes use of a perilymph cycling system, whereby a small outer volume includes a microcuvette with a so-called artificial round window. By this latter cycling technique, perilymph clearance kinetics of all kinds of radiotracers--with the exception of tritium labelled ones--can be measured. Calculations from clearance kinetics show that quite small particles with particle weights up to 100, such as the chlorine anion and the potassium cation, as well as urea, glycerol, pyruvate, and lactate, exhibit perilymphatic half-lives varying from 45 to 60 min. These half-live data are plausible in regard to cochlear blood flow measured previously via an independent technique developed by Angelborg et al.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Effects of heparin on vascularization of artificial skin grafts in rats.

Artificial skin is a recent development in the clinical care of the severely burned patient. Its manufacture entails the covalent bonding of collagen and polysaccharide, followed by the coating of one surface with a thin layer of silicone rubber. Artificial skin was grafted onto rats and examined for neovascularization at 7 days. Vascular patency was shown by perfused yellow latex casts. Five percent of the patent vessels grew into the graft soaked in physiological buffered saline (PBS). When the graft was soaked in heparin, 1 mg/ml buffered saline solution, before grafting, 54% of the patent vessels in the grafted area had grown into the matrix. These experiments show that the local application of heparin promotes early ingrowth of blood vessels into the healing site. The vascularity of artificial skin can be modified by heparin, which promotes angiogenesis, and leads to earlier deposits of greater amounts of new connective tissue.

Animals↗

Osmotic water permeability through liposomes in the presence of alpha 1-acid glycoprotein.

Alpha 1-acid glycoprotein (orosomucoid) from human blood serum was isolated in pure form and then reconstituted into large multilamellar liposomes, consisting of a binary mixture of hen-egg phosphatidylcholine and cholesterol. These liposomes were found to be osmotically sensitive. The osmotic water permeability of proteoliposomes was determined by light-scattering measurements of the osmotic volume changes after mixing with hyperosmotic solutions of potassium salts and aminoglycoside antibiotics. The initial rate of water outflow was measured as a function of glycoprotein concentration in the mixture for the preparation of proteoliposomes. This can serve as an indication for membrane permeability to the solutes used in these experiments. It was shown that aminoglycoside antibiotics passed much faster across the membrane than potassium salts, in the presence of glycoprotein in the liposomes. A recognition pattern in the osmotic behavior of these proteoliposomes was assumed.

Animals↗

The vascularization of artificial skin grafts in rats: its modification by protamine.

Artificial skin is a recent development in the clinical care of the severely burned patient. Its manufacture involves the covalent bonding of collagen and polysaccharide, followed by the coating of one surface with a thin layer of silicone rubber. Neovascularization and its modification in artificial skin were studied. Experimental artificial skin was grafted onto rats and examined for vascular growth in the graft at 7 days. This was revealed by latex-perfused vascular casts which were processed for histological study. An area including the graft bed and graft matrix was viewed and examined for latex-filled vessels. Thirty-seven percent of the total vessels, identified by residual latex, had grown into the graft. When artificial skin was treated with protamine at 10 mg/ml buffered saline solution before grafting, only 6% of the total perfused blood vessels were found in the graft matrix. The remainder was found in the graft bed. Moreover, increases in the numbers of perfused blood vessels and vessel diameters were observed in the graft bed at the interface below the graft pretreated with protamine. Protamine inhibited vessel growth into the matrix, but promoted an increased number of dilated blood vessels in the surrounding graft bed. These dilated vessels were related to an altered vessel architecture.

Animals↗