Analysis of the costs of surgery for Hirschsprung's disease: one-stage laparoscopic pull-through versus two-stage Duhamel procedure

The purpose of this report is to evaluate the cost-effectiveness of a single-stage laparoscopic pull-through for Hirschsprung's disease compared to the traditional two-stage Duhamel procedure. In this series of 33 children, the length of hospitalization (2.5 +/- 3.5 vs 10.6 +/- 3.9, p < 0.01), cost (19,088 +/- 13,075 vs 34,110 +/- 19,443, p < 0.05), and complications were all significantly less with the laparoscopic assisted pull-through compared to the more traditional open approach.

The effect of leukocyte infiltration on apoptosis in an in vitro thermal injury bioartificial living skin equivalent model

An in vitro bioartificial skin construct (BSC) model was studied to see how inflammatory infiltration affects apoptosis in skin that has been thermally injured. The BSC was used as a target organ. Control BSCs without leukocytes (CON) were burned (BCON) by scalding with phosphate-buffered saline heated to 70 degrees C for 6 seconds, and they were then cooled with room temperature phosphate-buffered saline for 15 seconds. Human alloimmunocytes were added to CON to create rejection cultures (REJ) and to BCON to create burned rejection cultures (BREJ). Slides were stained with hematoxylin and eosin and anti-Lewis antibody. In situ labeling of apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). Those sections that were immunostained for Lewis Y were analyzed for intensity stain index (ISI = [sigma P0 x I0]/ total tissue area in pixels). TUNEL was quantified with the following equation: no. of total apoptotic cells / total tissue area. Necrosis and blister formation in the epidermal layer were evident in BCON and BREJ. Pyknosis and nuclear fragmentation-indicators of apoptosis-were also present. Phagocytosis of keratinocytes by leukocytes was seen in REJ and BREJ. Immunostaining showed greater expression of Lewis Y antigen, as determined by ISI, in REJ as opposed to CON (58.2+/-2.3 vs. 36.4+/-2.3, respectively, P<.001), but no significant difference was found between BCON and BREJ (55.0+/-5.7 vs. 60.5+/-3.4, respectively) and REJ and BREJ (58.3+/-2.3 vs. 60.5+/-3.4, respectively). TUNEL staining indicated the presence of apoptosis as follows: REJ versus CON (0.0015+/-0.0002 vs. 0.0003+/-0.0001, respectively, P<.001); BREJ versus BCON (0.0031+/-0.0006 vs. 0.0018+/-0.0004, respectively, P<.05); REJ versus BREJ (0.0015+/-0.0002 vs. 0.0031+/-0.0006, respectively, P = .007). The presence of leukocytes and thermal injury induces apoptosis in BSC. The combination of these two variables results in increased apoptosis as determined by TUNEL. These findings suggest that a common pathway for skin injury may include inappropriate regulation of apoptosis exacerbated by a mechanism that includes inflammatory cellular infiltration.

Varicella arthritis diagnosed by polymerase chain reaction

We report a 2-year-old girl who developed acute arthritis of the left knee 4 days after the onset of a typical varicella infection. She was first thought to have pyogenic arthritis caused by Staphylococcus aureus. Accordingly, oxacillin was administered upon hospitalization. On the third day after hospitalization, bacterial cultures of the synovial fluid and blood showed no growth and oxacillin was discontinued. Although a viral culture of the synovial fluid for varicella-zoster virus (VZV) was negative, varicella DNA was identified by means of polymerase chain reaction (PCR) with VZV-specific primers. The patient recovered spontaneously. To differentiate this condition from septic arthritis is important. PCR is a sensitive technique that can demonstrate the presence of VZV DNA in synovial fluid, even if viral cultures are negative.

Fas-mediated induction of hepatocyte apoptosis in a neuroblastoma and hepatocyte coculture model

BACKGROUND

We have previously demonstrated an increase in hepatocyte apoptosis when they are cocultured with neuroblastoma cells. Death receptors in the tumor necrosis factor (TNF) family such as TNFR1 and Fas have been identified as regulators of apoptosis and may be responsible for the altered regulation of apoptosis seen in our coculture model. To evaluate the effects of released factors and remove the potential alterations induced by direct contact, a noncontact coculture system was used to study the interaction between hepatocytes and neuroblastoma cells.

METHODS

Human Chang hepatocytes (HC) were plated onto Falcon cell culture inserts with 0.45-micrometer pores in the permeable membrane. Human neuroblastoma cells (NB-IMR-32) were seeded into wells of the Falcon companion plate. After 24 h, inserts containing HC were placed into wells containing NB cells and incubated for 4 days. This provided a coculture environment without actual cellular contact. Immunohistochemical staining for TNFalpha, Fas, and Fas ligand (Fas-L) was performed. Apoptosis was detected via the TUNEL method. Images were analyzed with ImagePro-Plus. Statistical analyses were done with significance determined at P < 0.05.

RESULTS

Chang hepatocytes demonstrated a significant increase in the levels of TNF, Fas, and Fas-L when cocultured with neuroblastoma cells (P < 0.005). In addition, the cocultured hepatocytes had a 20-fold increase in the apoptotic rate (P < 0.001). Neuroblastoma cells had no demonstrable level of Fas or TNF when grown alone and in cocultures. Neuroblastoma cells that were grown alone had an elevated level of Fas-L, but this level diminished by 44% when cocultured with hepatocytes (P < 0.001).

CONCLUSION

An upregulated TNF/Fas receptor-ligand system may be responsible for increased apoptosis in hepatocytes when cocultured with neuroblastoma. This upregulation may be due to release of neuroblastoma-derived Fas ligand into the media. Tumors may alter the regulation of apoptosis in surrounding tissues via the death receptors.

Induction of apoptosis in a neuroblastoma and hepatocyte coculture model

BACKGROUND

The dysregulation of apoptosis may alter the progression of tumor growth and explain the clinical dichotomy observed in children with neuroblastoma (NB). An overexpression of the bcl-2 proto-oncogene induces resistance to apoptosis and has been observed in unfavorable NB. We hypothesized that alterations in apoptosis may be a result of the interactions between NB and the tissues surrounding it.

MATERIALS AND METHODS

Human Chang liver cells (HCL, 10(4) cells/cm2) were plated in two-chamber slides for 3 days. Human NB cells (10(5) cells/cm2) were added to one of the chambers and incubated for 3 more days. Control NB were plated under identical conditions in its own medium and in the HCL medium with growth curves measured. DNA fragmentation was detected via the TUNEL method (TdT-mediated nick end-labeling) and bcl-2 expression was determined by immunostaining.

RESULTS

NB growth was unaltered by the change in medium. NB stained mildly positive for bcl-2 when plated alone but became markedly positive in coculture. Histologically, HCL and NB appeared healthy when plated alone, but a halo of apoptotic HCL was seen around NB in the coculture. When plated alone, both NB and HCL demonstrated minimal apoptotic activity as detected via the TUNEL method. In the coculture, a halo of HCL surrounding the NB exhibited markedly increased DNA fragmentation and this intensity diminished in cells distant from the NB.

CONCLUSIONS

The regulation of apoptosis was altered in this coculture model of NB and HCL. HCL stimulated NB to overexpress bcl-2 and presumably become resistant to apoptosis. Conversely, NB induced the surrounding HCL to undergo apoptosis. The interaction between the local tissue and NB induced alterations in apoptosis in both cell types and resulted in a survival advantage for NB.

Predisposing factors of life-threatening deep neck infection: logistic regression analysis of 214 cases

OBJECTIVE

In the era of antibiotics, most deep neck infections can be cured by conservative treatment, but some still result in life-threatening complications. In this study, we discuss whether or not there are predisposing factors of complicated deep neck infection.

DESIGN

A retrospective chart review of patients presenting between 1988 and 1996 was conducted.

METHOD

Among 214 deep neck infection patients, 18 cases resulted in lethal complications. We used the "dummy" variable with logistic regression as the statistical analysis method.

RESULTS

Patients with an underlying disease, neck swelling, and delay time had a positive correlation that was statistically significance (p < .05). Patients who were older, male, with complete blood count/differential count-positive finding and fever had positive correlation, but this was not statistically significant (p > .05).

CONCLUSION

Although complicated deep neck infection is a rapidly progressive disease with a high mortality, we can not thoroughly predict the prognosis or avoid it happening completely. But, if we can detect and pay more attention to the high-risk group of patients with use of aggressive therapy, the incidence of complicated deep neck infection may be reduced.

The secreted hepatitis B precore antigen can modulate the immune response to the nucleocapsid: a mechanism for persistence

The hepatitis B precore Ag (HBeAg) is a secreted nonparticulate version of the viral nucleocapsid hepatitis B core Ag (HBcAg), and its function is unknown. A proportion of HBeAg-specific Th cells evade deletion/anergy in HBeAg-transgenic (Tg) mice and mediate anti-HBe "autoantibody" (autoAb) production after in vivo activation with the appropriate Th cell peptide. This model system was used to determine how secretory HBeAg may effect deletion of Th cells in the periphery. For this purpose, HBeAg-Tg mice were bred with Fas and Fas ligand (FasL)-defective lpr/lpr and gld/gld mutant mice. Fas-FasL interactions mediate activation-induced apoptosis in the periphery. In HBeAg-Tg/+ mice, high-titrated anti-HBe autoAb was produced that was exclusively composed of the IgG1 isotype (i.e., Th2-like profile). In contrast, HBeAg-Tg/lpr and HBeAg-Tg/gld mice produced significantly less anti-HBe autoAb, and the IgG isotype patterns were broadened to include IgG2a, IgG2b and IgG3 as well as IgG1 (i.e., mixed Th1/Th2-like profile). These results suggest that HBeAg-specific Th1 cells are preferentially depleted by Fas-FasL-mediated interactions. The effect of circulating HBeAg on HBcAg-specific Th1 cells was also examined by transferring HBe/HBcAg-specific Th cells into dual HBeAg- and HBcAg-expressing Tg recipient mice. The presence of serum HBeAg ablated the expected Th1-mediated anti-HBc Ab response and shifted it toward a Th2 phenotype. These results suggest that in the context of a hepatitis B viral infection, circulating HBeAg has the potential to preferentially deplete inflammatory HBeAg- and HBcAg-specific Th1 cells that are necessary for viral clearance, thereby promoting hepatitis B virus persistence.

Infradiaphragmatic extralobar pulmonary sequestration masquerading as an intra-abdominal, suprarenal mass

Three infants were found to have infradiaphragmatic masses by prenatal ultrasound. Postnatal imaging studies confirmed the presence of these masses, which were suspected of being intra-abdominal malignancies (neuroblastoma). The other principal differential diagnosis was extralobar pulmonary sequestration (EPS). Intraoperative findings were consistent with EPS, which was confirmed by histologic examination. We present these three infants, review the literature, and discuss the evaluation and treatment of infradiaphragmatic EPS.

Perinatal management of enteric duplication cysts of the tongue

Intra-oral enteric duplication cysts are rare. We recently treated two infants with prenatally diagnosed large sublingual enteric duplication cysts. Antenatal aspiration of the cyst was attempted in one infant without success. Because of the potential for airway obstruction and respiratory distress at delivery, preparation for an immediate tracheostomy was made in case oral intubation was impossible. Fortunately, aspiration of the cyst provided adequate access to the oropharynx for intubation in both infants. The placental cord was not divided until the airway was secured to minimize the potential for anoxic injury. Complete excision of the cyst was subsequently done in one patient. The other infant had an initial marsupialization and laser ablation of the cyst mucosa but the cyst recurred. Cyst excision at 9 months of age resolved the problem. Pathological examination revealed columnar-lined mucosa consistent with enteric duplication cysts. An enteric duplication cyst may present as a large sublingual mass with potential for airway obstruction in the newborn infant. Antenatal diagnosis allows for the proper preparation of personnel and equipment in the management of these neonates during delivery. If the airway is compromised, aspiration of the cyst can be done to improve the access to the oropharynx for intubation. Preparation for emergent tracheostomy should be done before delivery in case oral intubation is not possible. Subsequent complete cyst excision is the treatment of choice.

Laparoscopic common duct exploration in a child with recurrent pancreatitis due to a primary fungus ball in the terminal common bile duct

We report on a case of a fungus ball obstructing the distal common bile duct and causing recurrent pancreatitis in an otherwise healthy 3-year-old boy. Laparoscopic exploration of the common bile duct was performed using a 10 french rigid fiberoptic cystoscope and a Dormia basket. This is the first example of a primary fungus ball in common bile duct presenting as a pancreatitis and treated laparoscopically.

Tracheal hamartoma: report of a child with a neck mass

Tracheal hamartoma represents an oddity in children. Only one case was found in the English literature as a distal tracheal intraluminal lesion causing obstructive symptoms. All other reported cases were in older patients, who were presumed to have asthma or chronic obstructive pulmonary disease. The authors report on a 21-month-old girl who presented with an anterior neck mass fixed to the trachea. Imaging studies showed a lesion (2.5 x 2.3 x 1.7 cm) anterior to the right lobe of the thyroid, extending to the trachea posteriorly and down to the thoracic inlet inferiorly. The mass had a mixture of soft tissue densities with a focus of calcification. Results of thyroid studies were normal, and there was no adenopathy. Neck exploration showed a white, firm, lobulated mass fixed to the trachea, which was resected completely. The postoperative course was unremarkable. Histological studies showed a mixture of mature cartilage, fat, fibroconnective tissue, and spindle cells with myxoid degeneration, consistent with tracheal hamartoma. Based on a literature search, this is the first reported case of extraluminal tracheal hamartoma presenting as a neck mass in a pediatric patient.

Laparoscopic evaluation and treatment of intestinal malrotation in infants

Infants with intestinal malrotation present with bilious emesis and the diagnosis is generally obtained by an upper gastrointestinal barium study. Malrotation is suspected if the ligament of Treitz is not positioned to the left of the vertebral body. Barium enema may also be used to detect malrotation by noting the abnormal position of the cecum from its usual placement in the right lower quadrant, but this study is not as reliable due to the mobility of the cecum. Some infants may not have classic radiographic findings for malrotation, yet the contrast studies are not entirely normal. We recently treated two infants with recurrent vomiting whose UGI studies suggested intestinal malrotation. Laparoscopic exploration confirmed the diagnosis of malrotation. Laparoscopic correction (Ladd's procedure) of malrotation was carried out in one infant. The second infant underwent a traditional Ladd's procedure. The technique of laparoscopic Ladd's procedure is described. Laparoscopy may be used for the diagnosis and treatment of infants with intestinal malrotation. It may be especially helpful to verify the diagnosis in patients who do not have classic radiographic findings. Whether laparoscopy should be used in patients with midgut volvulus is debatable. Laparoscopic derotation of the volvulus in a setting where the bowel is markedly distended may be difficult and dangerous.

Complications of minimal-access surgery in children

Minimal-access surgery (MAS) is rapidly becoming the surgical approach of choice for a variety of surgical disorders in adults, but its use in children remains a relative novelty. Most pediatric surgeons continue to harbor justifiable concerns about the morbidity of this modality owing to the cumbersome nature of the instruments and the technical difficulty associated with two-dimensional views. The purpose of this study was to determine the complication rate and the lessons learned from the use of MAS in performing a variety of procedures in a large series of children. To determine complications, the authors reviewed the medical records of all children (n = 636; age range, 1 month to 19 years) who underwent laparoscopy (LAP) or thoracoscopy (THO) during a 5-year period (January 1, 1990 through December 31, 1994). The follow-up ranged from 1 week to 45 months. THO was performed in 62 children. Conversion to thoracotomy occurred in eight children (13%), because of inability to localize the lesion (3), unresectibility (2), inadequate tissue sample (1), unsafe access (1), hypoxemia (1), or inadvertent esophagotomy (1). Postoperatively, two ventilator-dependent children had tension pneumothorax after lung resection and required chest tubes. LAP was performed on 574 children, with conversion to laparotomy occurring in 15 (2.6%), because of technical reasons (10) or intraoperative complications (5). The complication rate of LAP was 2% (12 of 574). Early in the experience, intraoperative complications that led to laparotomy included hemorrhage during appendectomy (2), cholecystectomy (1), and splenectomy (1); and esophagotomy during a fundoplication (1). Other technical problems in the postoperative period were a malpositioned Nissen fundoplication and a gastric volvulus after gastrostomy and Nissen fundoplication owing to improper gastrostomy tube position. In addition, two children had a hernia at the umbilical trocar site that had been used for contralateral inguinal exploration, and cellulitis developed in three patients when a gastrostomy tube was brought out through a trocar site. Other complications not specific to MAS included pelvic abscess after appendectomy (5); small bowel obstruction after jejunostomy catheter placement (1) and combined cholecystectomy/appendectomy (1); enterocolitis (1) and severe hyponatremia (1) after pull-through for Hirschsprung's disease; and pneumonia after splenectomy (1). The overall complication rate of MAS was 4% (26 of 626), and there were no deaths. The initial use of MAS was associated with technical errors, which decreased with experience. Based on this study, the authors recommend (1) routine placement of a thoracostomy tube in children after THO if they require postoperative ventilator support; (2) using the open hernia sac to place a 70 degrees telescope for contralateral inguinal exploration; and (3) not using a trocar site for gastrostomy tube placement in immune-suppressed patients. With appropriate training and experience, MAS can be used safely in children, for a wide variety of diseases, with minimal morbidity and mortality.

The use of minimal access surgery in pediatric trauma: a preliminary report

Minimal access surgery (MAS) is becoming an accepted modality in the management of adult trauma, but its use in children is rarely reported. Recently, we began using minimal access surgery to evaluate injured children. The purpose of this report is to review our preliminary experience with the use of laparoscopy and thoracoscopy in blunt and penetrating pediatric trauma. Eight children aged 2-14 years old were evaluated using MAS. Two children with blunt injuries had persistent abdominal pain despite normal radiologic studies. Laparoscopy documented a disrupted gallbladder and a small bowel perforation. Laparoscopy was also used to evaluate five hemodynamically stable children with penetrating wounds to the abdominal wall with potential peritoneal penetration. Only one child was converted to a laparotomy. Four were found to have either tangential penetrating wounds or nonbleeding solid organ injuries and were spared an open exploration. Two children with penetrating trauma with potential mediastinal injury were assessed with thoracoscopy. MAS was also used as a therapeutic modality in two children who had diaphragmatic lacerations repaired with an endoscopic "hernia" stapler. MAS accurately identified all injuries. All children were subsequently discharged without complications. We conclude that MAS is a safe and effective way to evaluate and manage hemodynamically stable children with both penetrating and blunt traumatic injuries.

Influence of progressive tumor growth on glutamine metabolism in skeletal muscle and kidney

OBJECTIVE

The effects of progressive malignant growth on glutamine metabolism in skeletal muscle and in kidney were investigated.

SUMMARY BACKGROUND DATA

Fast-growing tumors consume considerable quantities of glutamine and lead to a decrease in circulating glutamine concentrations.

METHODS

Experiments were performed at various stages of tumor growth in rats implanted subcutaneously with the non-metastasizing methylcholanthrene-induced (MCA) fibrosarcoma and in pair-fed non tumor-bearing controls.

RESULTS

Tumor growth stimulated a twofold increase in hindquarter (muscle) glutamine release, which was not due to an increase in blood flow, but rather to a doubling in the fractional release rate. Consequently, a progressive decrease in skeletal muscle glutamine concentrations was observed over time. Simultaneously, the activity of glutamine synthetase (GS), the principal enzyme of de novo glutamine biosynthesis, increased more than twofold. This increase in muscle GS activity was accompanied by an increase in GS mRNA but the augmentation in GS expression apparently could not match the increased rate of efflux since muscle depletion developed. In rats with large tumors and severe glutamine depletion, GS activity was not elevated. Glutamine feeding increased muscle glutamine concentrations and glutamine synthetase specific activity. Although tumor growth led to the development of mild systemic acidemia, the classic renal adaptations normally observed, i.e., elevated glutaminase activity and accelerated renal glutamine utilization, were not present in acidotic tumor-bearing rats. Instead, renal GS activity was increased in tumor-bearing animals and ammoniagenesis was enhanced, in spite of a reduction in net renal glutamine uptake.

CONCLUSIONS

These data suggest that marked alterations in muscle and renal glutamine handling occur in the host with cancer; the enhanced muscle glutamine release in conjunction with no increase in renal consumption is consistent with increased glutamine uptake in other organs, most likely the tumor itself and the liver.

Adaptive Regulation in Skeletal Muscle Glutamine Metabolism in Endotoxin-Treated Rats

The effects of a single dose of endotoxin (7.5 mg/kg BW) on skeletal muscle glutamine metabolism were studied in vivo in rats to gain further understanding of the altered glutamine metabolism that characterizes sepsis and other catabolic diseases. In endotoxin-treated animals the arterial glutamine concentration fell early initially and then increased compared with control values. Twelve hours after treatment, the arteriovenous concentration difference for glutamine across the hindquarter doubled, resulting in a significant increase in net muscle glutamine release in endotoxin-treated rats. As a consequence, the muscle glutamine concentration fell in the endotoxin-treated animals by 25%-40%, an event that was apparent as early as two hours after endotoxin treatment. Skeletal muscle glutaminase activity, the major enzyme of glutamine breakdown, was unchanged by endotoxemia, but expression of glutamine synthetase mRNA and glutamine synthetase specific activity increased in a time-dependent fashion. The glutamine depletion that develops in skeletal muscle during endotoxemia is caused by accelerated muscle glutamine release rather than an increase in intracellular degradation or a fall in intracellular biosynthesis. The adaptive increase in glutamine synthetase expression that occurs requires de novo RNA and protein synthesis and may be designed to prevent complete depletion of the intracellular glutamine pool.

Mechanisms of accelerated hepatic glutamine efflux in the tumour-bearing rat

The mechanisms potentially controlling the net release of glutamine by the liver that occurs in tumour-bearing rats were investigated. Studies were undertaken when the tumour comprised approximately 7% (15 +/- 2 g) of total body weight. Hepatic glutamine gradient ratios were calculated by dividing hepatic glutamine content by arterial blood glutamine concentration. Both sodium-dependent and sodium-independent hepatocyte carrier-mediated glutamine transport were evaluated employing hepatic plasma membrane vesicles (HPMVs). In TBR the hepatic glutamine gradient ratio doubled (P < 0.001) secondary to a 52% increase in hepatic content (P < 0.005) and a 16% decrease in circulating glutamine (P < 0.001). Sodium-dependent glutamine transport was increased in HPMVs from TBR secondary to a 24 +/- 4% increase in the maximal velocity of transport (Vmax; P < 0.01) without alteration in apparent transporter affinity (Km). Saturable sodium-independent carrier-mediated glutamine transport was increased in HPMVs from TBR over CONT to a much greater relative degree owing to a 2.7-fold increase in transport Vmax (P < 0.05) without a change in transport Km. The accelerated hepatic efflux of glutamine which characterizes malignant growth appears to be the result of both mass-action gradient phenomena and alterations at the level of hepatocyte membrane transport activity.

Cytokine regulation of intestinal glutamine utilization

The effects of cytokines on intestinal glutamine metabolism were studied to gain further insight into the regulation of altered glutamine metabolism that occurs during severe infection. One hundred thirteen adult rats were given a single dose of interleukin-1 (IL-1, 50 micrograms/kg), tumor necrosis factor (TNF, 50 micrograms/kg or 150 micrograms/kg), or saline (controls), and flux studies were performed 4 or 12 hours later. Intestinal blood flow was not different between control and cytokine-treated animals at either time point. At the 4-hour time point, arterial glutamine fell by 16% to 21% in the cytokine-treated animals (p less than 0.05); at the 12-hour time point, the arterial glutamine concentration had returned to normal. Intestinal glutamine extraction decreased in the animals treated with IL-1 at both time points (4 hours: 13% +/- 1.3% in IL-1 versus 20% +/- 1.6% in controls, p less than 0.05; and 12 hours: 9% +/- 2% in IL-1 versus 17% +/- 2% in controls, p less than 0.05). Consequently, net intestinal glutamine uptake fell in the animals treated with IL-1 at both time points (p less than 0.05). Similarly, the activity of mucosal glutaminase, the principal enzyme of glutamine hydrolysis in the gut, fell by 50% in the 4-hour study (6.1 +/- 0.6 mumol/h/mg protein in IL-1 versus 9.6 +/- 0.8 mumol/h/mg protein in controls, p less than 0.01) and by 40% in the 12-hour study (5.4 +/- 0.5 mumol/h/mg protein in IL-1 versus 8.8 +/- 0.4 mumol/h/mg protein in controls, p less than 0.05). Concomitant with the aforementioned decrease in gut glutamine metabolism was a 25% incidence of positive blood cultures for gram-negative organisms in IL-1 treated rats studied at the 12-hour time point (p = 0.05 versus controls). In the doses administered and at the time points studied, TNF had no effects on the parameters of gut glutamine metabolism examined. The results indicate that IL-1 is a potential mediator of the alterations in gut glutamine metabolism observed in sepsis and endotoxemia.

Glutamine metabolism by the endotoxin-injured lung

The alterations in lung glutamine (GLN) metabolism that occurs in the endotoxin-injured lung were studied in rats and subsequently correlated with flux changes that occur in patients with the adult respiratory distress syndrome (ARDS). Measurements in animals were made at various time-points following the administration of endotoxin, while studies in surgical patients were done in a group of healthy controls, in patients with "early" sepsis who had normal chest x-ray films, and in patients with radiographic and physiologic evidence of ARDS. In healthy control rats, net amounts of GLN are released by the lungs into the systemic circulation. This release rate doubled 30 minutes after intravenous endotoxin (1,580 +/- 320 nmol GLN/100 g BW/min vs. 736 +/- 179 in controls, p less than 0.01) but glutamine synthetase activity was unchanged, suggesting an outpouring of cellular glutamine stores. Two hours after endotoxin treatment, this accelerated fractional release of glutamine by the lungs was no longer detected. By the 12-hour time-point, the lungs reversed to an organ of net glutamine balance (234 +/- 248 nmol/100 g BW/min, p less than 0.05 vs. controls and ENDO30 min) despite a more than two-fold increase in glutamine synthetase activity (p less than 0.01). Simultaneously, lung weights were increased by 21% (p less than 0.01) and histologic examination showed an interstitial infiltrate and pulmonary edema. Similar observations were made in humans; patients with "early" sepsis exhibited a marked increase in lung glutamine release, while patients with ARDS demonstrated glutamine balance across the lungs (4,030 +/- 910 nmol GLN/kg BW/min vs. 637 +/- 496 in ARDS, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

The effects of endotoxin on the splanchnic metabolism of glutamine and related substrates

The effects of endotoxemia on glutamine metabolism by the splanchnic bed was studied in vivo in adult rats 12 hours following administration of E. coli LPS. Glutamine uptake by the portal-drained viscera fell in the endotoxin-treated animals while glucose uptake doubled. Simultaneously, hepatic glutamine uptake increased ten-fold owing to both an increase in hepatic blood flow and glutamine extraction from the bloodstream. Hepatic alanine uptake, oxygen consumption, and glucose release were also accelerated in endotoxemic rats. The increase in liver glutamine utilization was associated with increases in parenchymal DNA and glutathione levels and an increase in glutathione and urea release into the systemic circulation. This marked increase in metabolic activity occurred in animals with chemical evidence of hepatocellular injury and histologic evidence of hepatocyte necrosis. During endotoxemia the liver becomes the major organ of glutamine consumption. This accelerated utilization provides carbons for energy and gluconeogenesis, nitrogen for ureagenesis, and substrate for nucleotide and glutathione biosynthesis in order to support cell repair and detoxification reactions.

Survey on use of antimicrobial agents and bacterial resistance in Huashan Hospital

A cross-section study was carried out to assess the general patterns in use of antimicrobial agents and the trends of bacterial resistance in Huashan Hospital. Of 2,400 patients whose charts were reviewed, 61% were given such drugs. 3,596 antibiotic courses were prescribed. Gentamicin was most frequently used. Results of the susceptibility test of 320 bacterial strains showed a high percentage of resistance against gentamicin, ampicillin, and chloramphenicol. Our findings suggest that antibiotic policies in the hospital need reappraising.