Synergism between two amphenicol of antibiotics, florfenicol and thiamphenicol, against Staphylococcus aureus.

Synergistic effects between the same class of antibiotics are rarely reported. In the current study, two amphenicols, namely florfenicol and thiamphenicol, exhibited both in vitro and in vivo synergism against clinical isolates ofStaphylococcus aureusfrom chickens, cattle and pigs. Checkerboard assays on 21S. aureusisolates showed that in 80 per cent of methicillin-susceptibleS. aureus(MSSA) and 82 per cent of methicillin-resistantS. aureus(MRSA) isolates tested, the minimal inhibitory concentration (MIC) of florfenicol could be reduced by 75 per cent (1/4 MIC) or more (up to 1/16 MIC) when combined with 1/2 MIC of thiamphenicol to exhibit antimicrobial activity comparable to the respective drugs at original strength (1×MIC). A synergistic effect (fractional inhibitory concentration index ≤0.5 or ≥2-log10decrease in colony-forming unit/ml in time-kill study) was evident against 30 per cent of MSSA and 45 per cent of MRSA strains tested. A study in mice revealed that the florfenicol/thiamphenicol combination at reduced dosages provided sufficient protection againstS. aureuschallenge. The possible mechanism warrants further study but likely includes the facilitated uptake of thiamphenicol via florfenicol action, and this facilitation was not limited to amphenicol class. The present study may offer new strategy for combination therapy and provide potential alternatives for effective treatment againstS. aureusinfections.

Two LINE 1 repeats in rat.

One LINE 1 repeat has been located 661 bp downstream from the last albumin exon and another approx. 10 kbp downstream from the last alpha-fetoprotein exon in the rat genomic DNA. The LINE 1 repeat following the albumin gene is truncated at its 5' end and is 1204 nucleotides long. The 5' end of the longer repeat downstream from the alpha-fetoprotein gene has not been determined. The two repeats have 95% homology with each other, with the exception of a short diverse 3' end sequence just preceding the putative polyadenylation signal.

A single apurinic site can elicit BAL 31 nuclease-catalyzed cleavage in duplex DNA.

The extracellular nuclease from Alteromonas espejiana BAL 31 is a highly sensitive endonucleolytic probe for lesions that distort the helical structure of duplex DNA. The nuclease can be isolated as two distinct molecular species, the 'fast' (F) and 'slow' (S) species, which have different kinetic properties. When nonsupercoiled, covalently closed circular phage PM2 DNA containing apurinic sites introduced by heating at acid pH was incubated with individual fractions from a chromatographic column which separated the two nuclease species, cleavage of the DNA was observed which was greatly in excess of control levels using nonmodified DNA. The initial rates of such cleavage clearly paralleled the peaks of both absorbance and nuclease activity against single-stranded and linear duplex substrates. When samples of apurinic DNA were incubated with pooled fractions from the same column representing pure F and S nucleases, respectively, the rate and extent of the cleavage observed was dependent upon the average number of apurinic sites per molecule. Cleavage was readily detectable in samples containing an average of 1.1 apurinic sites per molecule with both species of the enzyme. These results indicate that either species of the BAL 31 nuclease can recognize and cleave in response to a single apurinic site in duplex DNA. The F nuclease appears to be approx. 2.5-times as efficient in cleaving DNA containing apurinic lesions as the S enzyme in extended incubations.

Type I DNA topoisomerases from mammalian cell nuclei interlock strains and promote renaturation of denatured closed circular PM2 DNA.

Type I DNA topoisomerases from mouse ascites cell nuclei and from rat liver cell nuclei act on denatured viral closed circular PM2 DNA to produce molecules with a highly contracted structure as well as fully duplex non-supercoiled covalently closed circular molecules. Highly contracted DNA molecules contain a novel type of topological linkage in which a strand in one region of the double-stranded molecule passes between the strands in another region of the circular molecule one or more times. Since it is also found that the action of the topoisomerase promotes renaturation of complementary strands in denatured closed circular DNA, it is suggested that formation of contracted DNA structures proceeds through renatured, duplex intermediates with highly negative superhelix densities that contain small single-stranded regions.

Stomach rupture associated with physical struggle in a child.

A 5-year-old girl with spontaneous rupture of the stomach was treated successfully with excision of the ischemic edges of the perforation with primary repair. In this case, vigorous resistance against medical measurement resulted in rupture of the stomach, which was already distended with a large amount of fluid and air. The child survived following immediate surgical intervention and intensive postoperative care.

Rhabdomyosarcoma in children: clinical analysis of 20 cases.

Rhabdomyosarcoma is the most common soft tissue sarcoma in children. Twenty patients who were treated for rhabdomyosarcoma at this institution from 1979 to 1989 were reviewed. All of the patients were under 14 years of age. Two patients had tumors in the head and neck region (excluding the orbit), four in the orbit, seven in the trunk and extremities, five in the intra-abdominal or retroperitoneal region, and two in the urinary bladder. Eleven tumors were subclassified as the embryonal type, five as the alveolar type, one as the pleomorphic type, and the other three were not subclassified. Most patients received combined treatment with surgery and chemotherapy and/or irradiation. The overall one-year survival rate was 54% and the two-year survival rate was 31%. Several prognostic factors were identified. Longer-term survivors were younger than six years, had a histology of the embryonal subtype, were clinical group I or had tumors located in the orbit. Aggressive treatment is necessary to achieve a better outcome.

Toxic megacolon secondary to infective colitis in children.

BACKGROUND AND PURPOSE: Toxic megacolon is a fulminating and potentially lethal complication of severe colitis. Toxic megacolon secondary to infective colitis in children is rare. We analyzed the clinical course, pathology, treatment, and outcome of toxic megacolon secondary to infective colitis in children. METHODS: The medical records of all 20 children treated for infective colitis complicated with toxic megacolon during a 12-month (October 1997-October 1998) period were retrospectively reviewed. RESULTS: There were 10 boys and 10 girls, with a mean (+/- standard deviation, SD) age of 26.2 +/- 12.9 months (range, 6-57 mo). With an initial presentation of nonspecific gastroenteritis syndrome lasting several days, the disease progressed rapidly. In the acute stage, most patients developed toxic signs such as mental change, ranging from irritability to stupor (20, 100%), fever (19, 95%), tachycardia (20, 100%), abdominal distension (20, 100%), and abnormal stool pattern (19, 95%). Initial investigations revealed anemia (11, 55%), leukocytosis (11, 55%), and elevated levels of C-reactive protein ranging from 25.0 mg/L to 483.0 mg/L with a mean +/- SD of 185.7 +/- 129.1 mg/L (normal range, < 8 mg/L) (20, 100%). Salmonella enteritidis (12 patients, 60%) and Clostridium difficile (1, 5%) were isolated from stool samples in some cases. Plain abdominal x-rays revealed severe colonic dilatation. Prolonged hospitalization (mean, 33.6 d) and intensive therapy including a combination of broad-spectrum antibiotics, physical decompression, and total parenteral nutrition were necessary. Three patients (15%) underwent surgical management; the pathologic findings in these patients demonstrated severe transmural inflammation. We believe that bacterial and/or endotoxin translocation played an important role in gut failure. Three patients (15%) in the study died. CONCLUSION: Toxic megacolon in infective colitis is a fulminating illness that has a high mortality rate. The disease course can be divided into three stages: the acute toxic stage, the gut failure stage, and the convalescence or deterioration stage. Early diagnosis and aggressive management are important.

The physiological effect of CO2 pneumoperitoneum in pediatric laparoscopy.

BACKGROUND: The physiological effect of CO2 pneumoperitoneum during laparoscopy is a great concern of the anesthesiologists. Its effect in pediatric laparoscopy has not been previously reported. The purpose of this study was to examine the physiological alteration of pediatric patients during CO2 pneumoperitoneum. METHODS: One hundred and twenty six children aged from 11 mon to 13 yr undergoing laparoscopic inguinal exploration were divided into three groups based on age orientation: group I comprising 40 children with age from 11 mon to 2 yr; group II 46 children with age between 2 to 5 yr; and group III 40 children aged from 5 to 13 yr. All patients received endotracheal anesthesia with halothane-N2O in 50% O2 and atracurium for muscle relaxation. Respiration was controlled by an Ohmeda 7000 ventilator with constant minute ventilation to maintain baseline end-tidal CO2 tension (PETCO2) between 32-33 mmHg. After anesthesia, CO2 was insufflated into the peritoneal cavity via the opened hernia sac. The intraabdominal pressure exerted by CO2 was 10 mmHg and the duration of pneumoperitoneum and laparoscopy was 15 min. We recorded airway pressure, PETCO2, body temperature, blood pressure, heart rate, heart rhythm, and oxygen saturation simultaneously at 1 min interval before, during, and after laparoscopy. RESULTS: The airway pressure and PETCO2 showed significant increases during laparoscopy (15-18% and 18-20% respectively) in all cases, but the percentage of increases were not significantly different among groups. However, the PETCO2 change in terms of time lag were different between groups: (1) the time lag from CO2 insufflation to the emergence of PETCO2 change (latent period) was respectively 0.7 +/- 0.1 (mean +/- SD) min in group I, 0.9 +/- 0.2 min in group II and 1.5 +/- 0.2 min in group III (p < 0.05); (2) the PETCO2 change from baseline to a plateau (ascending period) was respectively 4.2 +/- 0.6 min in group I, 6.3 +/- 1.0 min in group II and 9.1 +/- 1.1 min in group III (p < 0.05); (3) the PETCO2 decline from plateau to baseline after CO2 deflation (descending period) was respectively 6.2 +/- 0.5 min in group I, 8.3 +/- 0.8 min in group II and 12.0 +/- 1.3 min in group III (p < 0.05). The body temperature and hemodynamics including blood pressure, heart rate, heart rhythm, oxygen saturation were not significantly changed during laparoscopy in all groups. CONCLUSIONS: The changes of PETCO2 during laparoscopy did not influence the hemodynamic stability in our study. The younger children give a faster reaction time of PETCO2 change after CO2 insufflation than do the older children which may be related to the variation of physiological exhibition at different state of development.

Pelvic abscess after ultrasound-guided aspiration of endometrioma: a case report.

A 31-year-old female with four years of infertility due to endometriosis and severe pelvic adhesions underwent transvaginal ultrasound-guided aspiration of an ovarian endometrioma before ovulation induction for in vitro fertilization (IVF) and embryo transfer. Seven days following the aspiration, the patient developed acute abdominal pain; diagnostic laparoscopy was performed at a local medical center, revealing a right tubo-ovarian abscess. Exploratory laparotomy ensued and right salpingo-oophorectomy was performed. A combination regimen of three antibiotics was administered and the patient was transferred to the intensive care unit of the Cathay General Hospital two days after surgery for further care. Her postoperative condition was uneventful and she recovered quickly. The patient then continued with further IVF treatment.

[Intravenous infection of C. albicans induces apoptosis of cortical thymocytes in mice].

In this study, we aimed to understand the location of apoptotic cells in murine thymus and phenotype of murine thymocytes involved in C. albicans induced apoptosis. Results showed that significant increase of apoptotic cells in thymus began at 6 h after intravenous injection of C. albicans and kept increased at 12 h, 18 h and 24 h. Quantitative changes of thymocytes with different phenotype measured by flow cytometry revealed that percentage of CD3+ and CD8+ cells were significantly reduced compared to the controls. Moreover in situ cell death detection of thymic tissue revealed that apoptotic cells induced by C. albicans mainly located in the thymic cortex, while in the thymic medulla a very small number of thymocytes was involved. Taken together our study indicates that C. albicans induces apoptosis of murine thymocytes, moreover the apoptosis possibly involves the major immature CD3+ CD4+ CD8+ cells in the thymic cortex and minor mature CD3+ CD4- CD8+ cells in the thymic medulla.

Catheter-related complications of continuous ambulatory peritoneal dialysis.

OBJECTIVE: To assess the effectiveness of continuous ambulatory peritoneal dialysis (CAPD) with particular reference to morbidity. DESIGN: Open study. SETTING: Two city general hospitals. SUBJECTS: 104 Adults and 11 children with end stage renal failure. MAIN OUTCOME MEASURE: Morbidity. RESULTS: There were 29 complications (25%), the most common being obstruction of the tube (n = 8, 7%), and migration of the tube (n = 7, 6%). Others were peritonitis (n = 5), haemorrhage (n = 4), infection at the exit site (n = 3), and leakage of fluid (n = 2). All were readily treatable. CONCLUSIONS: Fixing the catheter in two places may prevent its migration. The complication rate of CAPD is acceptable, and in children with end stage renal failure it is a suitable alternative to haemodialysis while they are waiting for renal transplantation.

Successful surgical treatment of bilateral congenital chylothorax: a case report.

A male infant was diagnosed at 19 days old to have a right chylothorax. Conservative management, including median-chain triglyceride (MCT) diet, total parenteral nutrition (TPN) and chyle drainage, were unsuccessful. The boy received a right thoracotomy with ligation of the thoracic duct and sutures of leaking lymphatic ducts at the age of 65 days. The result of the operation was satisfactory but left chylothorax developed six days later. Left thoracotomy was performed eight days later to suture the leaking lymphatic chains and finally the patient recovered well. Followed for one year, the patient's physical development was satisfactory. Prompt surgical intervention for congenital chylothorax is strongly recommended, if medical treatment fails.

Value of gamma-glutamyl transpeptidase for early diagnosis of biliary atresia.

BACKGROUND: Early diagnosis of congenital biliary atresia (BA) is important because the prognosis is closely related to timing of a hepaticoportoenterostomy. In this study, we discuss whether the elevation of serum gamma-glutamyl transpeptidase (GGT) is accurate for the early differentiation of BA from neonatal hepatitis (NH). METHODS: The effectiveness of using GGT before the age of 10 weeks and other tools in the differential diagnosis of BA and NH were analyzed retrospectively by reviewing the charts of 29 BA and 12 NH patients. The results of serial liver enzyme studies, abdominal sonography, hepatobiliary scintigraphy and transcutaneous liver biopsy were compared between both groups. RESULTS: The peak GGT value in BA before 10 weeks of age was significantly higher than that in NH (622.5 +/- 211.9 U/l vs 168.8 +/- 100.3 U/l, respectively, p < 0.001). When a serum GGT concentration greater than 300 U/l was used as a diagnostic criterion for BA in patients younger than 10 weeks of age, the diagnostic accuracy was 85%. When an increase in GGT value (in serial measurements) of greater than 6 U/l/day was used as a criterion, the accuracy was 88%. The diagnostic accuracy of abdominal sonography, hepatobiliary scintigraphy and liver biopsy was 68%, 67% and 79%, respectively. CONCLUSIONS: GGT concentration is diagnostically valuable when the results of other diagnostic methods are not available, or are controversial, in differentiating between BA and NH.

Intraoperative non-puncture laparoscopic examination of contralateral internal inguinal rings is feasible in children with unilateral hydrocele.

BACKGROUND: Intraoperative non-puncture laparoscopic examination using the hernia sac as the scope entrance has been successfully conducted in children with unilateral inguinal hernia. This technique selects patients for contralateral inguinal exploration. In spite of the thin and narrow processus vaginalis, children with unilateral hydrocele encounter the same problem of subsequent contralateral inguinal hernia or hydrocele. In this study, we discuss the feasibility of this technique in children with unilateral hydrocele. METHODS: From July 1993 to September 1995, 91 children with unilateral hydrocele were examined during surgery at our institution. The results, including success rate, complications, patent rate of contralateral internal ring and contralateral subsequent hernia or hydrocele, at at least one year follow-up, were compared with those of 329 children with unilateral hernia undergoing the same examination during this period. RESULTS: A patent contralateral processus vaginalis was recognized in 31 children and all were confirmed by surgical exploration. The examination failed in three patients, of whom two had a tear in the processus vaginalis and one had retroperitoneal air dissection as a result of false insertion of the laparoscopic sheath. One patient had a postoperative wound infection. No patient with contralateral obliterated processus vaginalis developed inguinal hernia or hydrocele during follow-up of at least one year. The results were similar to those of the 329 children with hernia who underwent the same procedure in the same period. CONCLUSIONS: Intraoperative non-puncture laparoscopic examination is feasible in children with unilateral hydrocele.

Hypospadias repair using a double onlay preputial flap.

From an anatomical view, a more reasonable blood supply can be achieved in hypospadias repair using a double-faced onlay flap. A urethroplasty was performed in 15 patients with middle or posterior hypospadias using a double-faced onlay preputial flap (DOPF). In this method, the urethral plate is preserved and a double-faced preputial flap is developed. The inner face of the flap is sutured to the urethral plate to create the neourethra and the outer face together with the rest of the dorsal prepuce is used for ventral skin coverage. Postoperative complications occurred in 2 patients: 1 developed a fistula in the subcoronal region and 1 had dorsal skin necrosis and suture disruption of the glanular wings. The overall complication rate was 13%. The DOPF provides a well-vascularized ventral skin cover and reduces the area of avascular dorsal skin. The viability of the neourethra can be evaluated by simply looking at the outer face of the flap. However, the complication rate is similar to that of other techniques.

Histiocytosis X involving thyroid gland: a case report.

Diffuse histiocytosis X involving thyroid gland is rare. A 10-year-old boy with progressively enlarged neck mass, skin rash over scalp and face, splinter hemorrhage, otitis externa, episodes of pneumothorax and abnormal liver function was hospitalized. Thyroid scan showed a nonfunctioning mass in the right lobe of the thyroid and needle aspiration biopsy suspected histiocytosis X. Right thyroid lobectomy was performed and revealed histiocytosis X in light and electron microscopic examinations.

Dilatation of the biliary tract in pediatric patients.

Forty cases of dilatation of the biliary tract in infants and children were diagnosed and treated at the Veterans General Hospital, Taipei and Taichung between 1980 and 1992. The male to female ratio was 1:2.6 and the age ranged from 1 day to 14 years. Major clinical presentations were abdominal pain (57.5%), jaundice (42.5%), vomiting (37.5%) and abdominal mass (30%); the classical triad of abdominal pain, jaundice and abdominal mass occurred in only three cases (7.5%). Abnormal liver function tests included elevated bilirubin (Bil) (22/37), aminotransferase (30/40), alkaline phosphatase (Alk-P) (34/37), lactic dehydrogenase (LDH) (22/34) and gamma-glutamyl transpeptidase (GGT) (13/15). The amylase in bile was detected in 16 cases with 10 cases higher than 500 Somogyi units/dL. All cases were diagnosed correctly, using real time sonography. Technetium-labeled scintiscan (Tc-99m DISIDA scan) was interpreted correctly in 88% (15/17) and abdominal computerized tomography (CT) in 10 cases (10/10). According to Todani's classification, type I cyst was the most common (35 cases, 87.5%) and the remaining cases were type IV-A (3 cases) and type V (2 cases). Operation was performed in 38 cases except for two who had type V dilatation of biliary tract (Caroli's disease). Complications included rupture of the gall bladder in two patients and common bile duct stone in one; mortality after operation occurred in one case. Surgical specimens of the liver revealed periportal fibrosis in nine instances.

Isolation and comparison of two molecular species of the BAL 31 nuclease from Alteromonas espejiana with distinct kinetic properties.

The extracellular nuclease from Alteromonas espejiana sp. BAL 31 can be isolated as two distinct proteins, the "fast" (F) and "slow" (S) species, both of which have been purified to homogeneity. The F and S species of the nuclease have molecular weights, respectively, of 109 X 10(3) and 85 X 10(3), and both are single polypeptide chains with an isoelectric pH near 4.2. Both species catalyze the degradation of single-stranded and linear duplex DNAs to 5'-mononucleotides. The degradation of linear duplex DNA occurs through a terminally directed hydrolysis mechanism that results in the removal of nucleotides from both the 3' and 5' ends. Apparent Michaelis constants (Km) have been obtained for the exonuclease activities of both species and for the activity against single-stranded DNA of the S species. The Km for the hydrolysis of single-stranded DNA catalyzed by the F species has not been obtained because the reaction velocity was maximal even at the lowest substrate concentrations accessible in the photometric assay. The ratio of the turnover numbers for the exonuclease activities of the two species indicates that the F species will shorten linear duplex DNA at a rate 27 +/- 5 (S.D.) times faster than an equimolar concentration of the S species in the limit of high substrate concentration, while the corresponding ratio for the activities against single-stranded DNA (1.2 +/- 0.1) shows that the two species are similar with respect to hydrolysis of this substrate. In the limit of high substrate concentrations, the F and S species break phosphodiester bonds in single-stranded DNA at rates 1.3 +/- 0.3 and 33 +/- 2 times those for the exonucleolytic degradation of linear duplex DNA, respectively. It has not been established whether the two species are physically related.

Isolation and characterization of the human apolipoprotein A-II gene. Electron microscopic analysis of RNA:DNA hybrids, nucleotide sequence, identification of a polymorphic MspI site, and general structural organization of apolipoprotein genes.

Three cloned apolipoprotein A-II genes were isolated from a human genomic cosmid library constructed in our laboratory. An approximately 3-kilobase HindIII insert containing the entire gene was analyzed by RNA:DNA hybridization and electron microscopy. The apo-A-II gene was found to consist of 4 exons and 3 intervening sequences (IVS), and the lengths of each exon and IVS were estimated by direct observation of the hybrids. The entire approximately 3-kilobase HindIII insert was sequenced. The 5' end of the gene was determined by primer extension. The DNA sequence confirms the presence of 4 exons and 3 IVS: exon 1, 34 nucleotides; exon 2, 76 nucleotides; exon 3, 133 nucleotides; exon 4, 230 nucleotides; IVS-I, 169 nucleotides; IVS-II, 299 nucleotides; and IVS-III, 396 nucleotides. A "TATA box" is located at position -29 from the CAP site. A "CAT box" is present at position -78. A "TG" element consisting of (TG)19 is identified at the 3' end of IVS-III. Furthermore, an enhancer core sequence, CTTTCCA, is identified at position -355 in the 5' flanking sequence. At positions -497 to -471 upstream from the CAP site is a stretch of 27 nucleotides that show high homology to stretches of 5' flanking sequences in the apo-C-II, apo-A-I, apo-E, and apo-C-III genes. An Alu dimer sequence is located approximately 300 nucleotides from the 3' end of the gene. Within this Alu sequence, we have identified a polymorphic MspI site. Restriction fragment length polymorphism involving this site has been previously shown to correlate with apo-A-II levels and high density lipoprotein structure. Analysis of conformation by Chou-Fasman analysis and by the helical hydrophobic moment of Eisenberg et al. (Eisenberg, D., Weiss, R. M., and Tergwillager, T. C. (1982). Nature (Lond.) 299, 371-374) indicates that in all of the 5 apolipoproteins characterized at the nucleotide level to date, i.e. apo-C-II, apo-A-II, apo-E, apo-A-I, and apo-C-III, the 2 IVS within the peptide coding regions of the gene tend to occur at regions corresponding to the surface of the polypeptide chain and divide the protein into distinct functional domains.