Classification and treatment of pooling of contrast material on computed tomographic scan of blunt hepatic trauma

BACKGROUND

Pooling of contrast material on computed tomographic (CT) scan represents free extravasation of blood as a result of active bleeding. For patients with blunt hepatic injury, aggressive management such as angiography or celiotomy is usually indicated if this sign is detected. The purposes of this study were to further categorize this CT scan finding and to correlate its characteristics with clinical outcomes. This CT scan classification might be helpful for the selection of appropriate management.

METHODS

During a 42-month period, 276 patients with blunt hepatic injury were treated. Two hundred twelve of them were hemodynamically stable after initial resuscitation and underwent abdominal CT scan examination. Pooling of contrast material was detected on the CT scans of 15 patients. The CT scans and medical records were reviewed. Special attention was paid to the presence, location, and character of the extravasated contrast material.

RESULTS

The finding of pooling of contrast material on CT scan was categorized into three types according to its location and character. Type I showed extravasation and pooling of contrast material in the peritoneal cavity (six patients). All patients with type I CT scan findings became hemodynamically unstable soon after CT scan examination and required emergent laparotomy. Type II findings showed simultaneous presence of hemoperitoneum and intraparenchymal contrast material pooling (six patients). Four patients with type II CT scan findings required laparotomy for hemostasis. Type III findings showed intraparenchymal contrast material pooling without hemoperitoneum (three patients). All patients with type III CT scan signs remained hemodynamically stable.

CONCLUSION

With the use of a high-speed spiral CT scanner, it is possible to predict the necessity of operative management or angiography for patients with blunt hepatic injury before deterioration of hemodynamic status. The presence of pooling of contrast material within the peritoneal cavity indicates active and massive bleeding. Patients with this CT scan finding show rapid deterioration of hemodynamic status. Most of these patients might require emergent surgery. Pooling of contrast material in a ruptured hepatic parenchyma indicates active bleeding. Close monitoring and emergent angiography should be performed. Deterioration of hemodynamic status in these patients usually requires prompt surgical intervention. Intraparenchymal pooling of contrast material with unruptured liver capsule often indicates a self-limited hemorrhage. Patients with this CT scan finding have a high possibility of successful nonoperative treatment.

Pooling of contrast material on computed tomography mandates aggressive management of blunt hepatic injury

BACKGROUND

Nonoperative management of blunt hepatic injury is currently a widely accepted treatment modality. Computed tomography (CT) is an important imaging study both for diagnosis and follow-up of these patients. There is, however, no reliable predictor of failure of nonoperative treatment other than the ultimate development of hemodynamic instability. Previous reports mostly were based on the data obtained from low-speed dynamic incremental scanners. The purpose of this study is to evaluate the value of a high-speed helical scanner in predicting the outcome of patients managed nonoperatively.

METHODS

During a 30-month period, 194 patients with blunt hepatic injury were treated, 150 of them were hemodynamically stable after initial resuscitation and underwent abdominal CT examination. All CT scans were performed with the High Speed Advantage Scanner. The CT scans and medical records were reviewed.

RESULTS

Nonoperative management was successfully applied to all patients with grade I and II, 93% of grade III, 87% of grade IV, and 67% of grade V liver injuries. Twelve patients required liver-related celiotomy. Pooling of contrast material was detected on the CT scans of 8 patients. Six (75%) of these patients developed hemodynamic instability and required liver-related celiotomy later. Pooling of contrast material can be detected in 50% of the patients receiving liver-related celiotomy.

CONCLUSION

The presence of pooling of contrast material within the hepatic parenchyma indicates free extravasation of blood as a result of active bleeding. In patients with blunt hepatic injury, if this sign is detected, nonoperative treatment should be terminated and angiography or celiotomy undertaken promptly. With the increasing use of high-speed spiral CT scanner and improvement in scanning technique, pooling of contrast material may become a sensitive sign for active bleeding and may be used as a guide for the selection of treatment modality.

CT grading of blunt pancreatic injuries: prediction of ductal disruption and surgical correlation

PURPOSE

The purpose of our study was to devise a CT grading scheme for blunt pancreatic injuries (BPIs) and to apply it to predict the presence or absence of ductal disruption.

METHOD

We retrospectively reviewed CT scans of 22 patients with proven BPIs. We graded these injuries on CT (A, BI, BII, CI, and CII) based on the (a) presence or absence of pancreatic lacerations, (b) site of lacerations, and (c) depth of lacerations. CT grading was correlated with surgical findings for glandular and ductal injuries.

RESULTS

Main pancreatic ducts were intact in 2 patients with normal CT scans and in all grade A injuries (n = 10). Distal pancreatic ducts were disrupted in all grade B injuries (BI, n = 1; BII, n = 4). Of five grade C injuries, three CII injuries had disruption of proximal pancreatic duct, one CII injury had disruption of minor duct, and one CI injury had an intact ductal system.

CONCLUSION

CT grading of BPIs was useful in predicting ductal integrity or disruption. Ductal disruption was likely present if the pancreas appeared to have a transection or deep laceration on CT scans. It was accurate in grade A and B injuries. Overestimation could occur in grade CI and CII injuries.

A conformational switch in nuclear hormone receptors is involved in coupling hormone binding to corepressor release

Nuclear hormone receptors are ligand-regulated transcription factors that modulate gene expression in response to small, hydrophobic hormones, such as retinoic acid and thyroid hormone. The thyroid hormone and retinoic acid receptors typically repress transcription in the absence of hormone and activate it in the presence of hormone. Transcriptional repression is mediated, in part, through the ability of these receptors to physically associate with ancillary polypeptides called corepressors. We wished to understand the mechanism by which corepressors are recruited to unliganded nuclear hormone receptors and are released on the binding of hormone. We report here that an alpha-helical domain located at the thyroid hormone receptor C terminus appears to undergo a hormone-induced conformational change required for release of corepressor and that amino acid substitutions that abrogate this conformational change can impair or prevent corepressor release. In contrast, retinoid X receptors appear neither to undergo an equivalent conformational alteration in their C termini nor to release corepressor in response to cognate hormone, consistent with the distinct transcriptional regulatory properties displayed by this class of receptors.

Serum lactic dehydrogenase strongly predicts survival in metastatic nasopharyngeal carcinoma treated with palliative chemotherapy

BACKGROUND AND OBJECTIVE

The survival outcomes of patients with metastatic nasopharyngeal carcinoma (NPC) differ significantly between individuals. This study aimed to evaluate whether serum lactic dehydrogenase (S-LDH) level had a clinical value in predicting clinical response and survival outcome for patients with metastatic NPC.

METHODS

S-LDH level was measured at baseline and then before every cycle of treatment in 689 NPC patients with distant metastases. Correlations of pre-treatment and post-treatment S-LDH levels to response of treatment and survival were analysed retrospectively.

RESULTS

Patients with elevated values of pre-treatment S-LDH (>245 IU/L) had significantly worse survival than those with normal values of pre-treatment S-LDH (≤245 IU/L) (P<0.001). Patients with elevated values of post-treatment S-LDH had worse survival compared with those with normal values of post-treatment S-LDH (P<0.001). Patients with normal values of pre-treatment and post-treatment S-LDH showed the highest response rate and the most favourable prognosis.

CONCLUSION

S-LDH appears to be a significant independent prognostic index in patients with disseminated NPC that should be considered in the comparison of the results achieved with different therapies and in planning new randomised clinical therapeutic trials.

Long-term results of endoscopic stent in the management of blunt major pancreatic duct injury

BACKGROUND

Pancreatic stents can be used to treat a variety of acute and chronic pancreatic lesions. Sporadic successful trials in trauma patients have been reported. To our knowledge, however, a series with long-term follow-up has not previously been reported. We treated six patients in a 6-year period and report the long-term results.

METHODS

From February 1999 to February 2005, six blunt-trauma patients with major pancreatic duct disruption were treated with pancreatic duct stent at a single trauma center. Assessment of injury severity and diagnosis were based on abdominal computed tomography (CT) and proved by endoscopic retrograde pancreatography (ERP), with chart review used to establish mechanism of injury, timing of ERP, and stent placement, as well as the long-term outcome.

RESULTS

Three of the six injuries were classified AAST grade III and three were grade IV; the interval to ERP with stent placement ranged from 8 hours to 22 days after the injury. One patient developed sepsis and died. One patient's stent could be removed early (52 days post-stenting) with mild ductal stricture, whereas the other four were complicated by severe ductal stricture that required repeated and prolonged stenting treatment. Removal of the stents was only possible in three of these four cases (at 12, 19, and 39 months, respectively), with stent dislodgment in the pancreatic duct occurring in another.

CONCLUSIONS

Stent therapy may avoid surgery in the acute trauma stage, and may be preserved as another choice for acute grade IV pancreatic injury. However, variant outcome and long-term ductal stricture reveal that the role of pancreatic duct stent is uncertain and may not be suitable for acute grade III pancreatic injury. However, it needs more clinical data to define the value in the acute blunt pancreatic duct injury.

Factors determining operative mortality of grade V blunt hepatic trauma

BACKGROUND

Despite recent advances in the management of severe hepatic injuries, the operative mortality rate of grade V hepatic injuries still ranges from 67% to 80%. Grade V hepatic injuries involving the retrohepatic cava or main hepatic veins are almost always lethal, especially those from blunt trauma. The purpose of this study is to understand the risk factors determining operative mortality in grade V blunt hepatic trauma, and to try to improve the surgical management of these injuries.

METHODS

A retrospective study was conducted at a medical center that offers services including primary, secondary, and tertiary care. Forty-four patients with grade V blunt hepatic injuries were treated during a 6-year period from January 1, 1991, to December 31, 1996. The operative mortality was compared by a multivariate analysis.

RESULTS

Forty-four patients with grade V blunt hepatic injuries were identified. Seven patients had only parenchymal injuries, and the others had vascular and associated parenchymal injuries. Venorrhaphy was used in 37 patients; 29 were treated using a nonshunting approach, and 8 with an atriocaval shunt. The overall mortality rate was 68% (30 of 44), and liver-related mortality was 50% (22 of 44). Univariate analysis revealed that the significant variables affecting operative mortality were initial systolic blood pressure, initial base deficit, the Glasgow Coma Scale, injury type, number of resected segments, and total intraoperative blood loss. Based on forward stepping logistic regression analysis, patients with an initial base deficit of -6 mmol/L or less (relative risk = 17.3), and a total intraoperative blood loss of 5,000 mL or more (relative risk = 23.5) would, significantly, encounter a worsening prognosis.

CONCLUSIONS

Initial base deficit and total intraoperative blood loss were the significant factors that determined operative mortality after grade V blunt hepatic trauma. We suggest that prompt resuscitation and expeditious and appropriate surgical management, to control operative blood loss, is the only way to reduce operative mortality in patients with grade V blunt hepatic trauma.

Small bowel perforation: is urgent surgery necessary?

BACKGROUND

Controversies regarding how urgent bowel perforation should be diagnosed and treated exist in recent reports. The approach for early diagnosis is also debatable. The purposes of this study were to evaluate the relationship between treatment delay and outcome of small bowel perforation after blunt abdominal trauma and to determine the best assessment plan for the diagnosis of this injury.

METHODS

One hundred eleven consecutive patients with small bowel perforations caused by blunt abdominal trauma were retrospectively reviewed. The patients were divided into four groups according to the time interval between injury and surgery. Hospital stay, time to resume oral intake, and mortality and morbidity rates were compared between groups. Physical signs, laboratory and computed tomographic findings, and the results of diagnostic peritoneal lavage were analyzed to find the most sensitive and specific test for early diagnosis of small bowel perforation.

RESULTS

Delay in surgery for more than 24 hours did not significantly increase the mortality with modern method of treatment; however, complications increased dramatically. Hospital stay and time to resume oral intake increased significantly when surgery was delayed for more than 24 hours. Abdominal tenderness was a common finding, but it was not specific for bowel perforation. Only 40% of the computed tomographic scans were diagnostic for bowel perforations: 50% of them showed suggestive signs, and 10% were considered as negative. Persistence of abdominal signs indicated peritoneal lavage. By using cell count ratio in diagnostic peritoneal lavage and/or increased lavage amylase activity, presence of particulate matter and/or bacteria in the lavage fluid, all patients with intraperitoneal bowel perforation were diagnosed accurately before operation.

CONCLUSION

Small bowel perforation has low mortality and complication rates if it is treated earlier than 24 hours after injury. The principle of "rushing to the operation suite" for a stable blunt abdominal trauma patients without detailed systemic examination is not justified. The priority of treatment for the small bowel perforation should be lower than the limb-threatening injuries. Diagnostic peritoneal lavage provides high sensitivity and specificity rates for the diagnosis of small bowel perforation if a specially designed positive criterion is applied.

Selective application of laparoscopy and fibrin glue in the failure of nonoperative management of blunt hepatic trauma

BACKGROUND

Most blunt hepatic trauma patients can be managed nonoperatively. The current failure rate in adult blunt hepatic trauma is reportedly 0 to 19%. We wished to evaluate the applicability of laparoscopy and fibrin glue as a minimally invasive alternative to laparotomy in these unsuccessfully nonoperative cases.

METHODS

All adult patients with blunt hepatic trauma managed nonoperatively at Linkou, Chang Gung Memorial Hospital Medical Center, Taipei, Taiwan, over a 2-year period from July 1, 1994, to June 30, 1996, were eligible for the study. A laparoscopic examination was performed on those who failed conservative care before undertaking an exploratory laparotomy. Fibrin glue was sprayed over the wound surface if ongoing hemorrhage was evident from any liver laceration. The clinical data, operative and laparoscopic findings, operative methods, and outcomes of these patients were studied.

RESULTS

Of the 61 patients, 55 patients were successfully treated without operation. Of the six failures (10%) all were liver related. After the introduction of laparoscopy, the nontherapeutic laparotomy rate would have decreased from 100% (6 of 6) to 50% (3 of 6), and with the adjunctive use of fibrin glue, the laparotomy rate went down to 0% (0 of 6). There were no deaths among the six patients receiving laparoscopy and fibrin glues; and only one developed a liver abscess, for a morbidity rate of 17% (1 of 6).

CONCLUSIONS

The selective use of laparoscopy and fibrin glue can effectively reduce the nontherapeutic laparotomy rate among blunt hepatic trauma patients who fail nonoperative management.

Surgical treatment and outcome after delayed diagnosis of blunt duodenal injury

OBJECTIVE

To review our experience of 18 patients with duodenal injuries after blunt trauma, the diagnosis of which had been delayed for more than 24 hours.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Taiwan, R.O.C.

SUBJECTS

18 patients who presented with duodenal injuries between January 1986 and December 1995.

MAIN OUTCOME MEASURES

Morbidity and mortality.

RESULTS

The reasons for the delay were: injuries not found during the first operation (n = 6), patients had not sought medical help (n = 6), and injuries treated conservatively at local hospitals (n = 5). There was one delay in our department because the patient lost consciousness. 12 patients were treated by pyloric exclusion with no deaths and four complications (one duodenal fistula and 3 retroperitoneal abscesses). The other 6 had various operations including pancreaticoduodenectomy, jejunostomy, and gastrostomy, with six complications and one death, giving an overall mortality of 6% and morbidity of 50%. Three patients developed delayed extensive retroperitoneal abscesses and all three were treated successfully by laparostomy. 16 of the 18 patients required enteral feeding through a jejunostomy.

CONCLUSIONS

Though the complication rate was high, the use of pyloric exclusion and a feeding jejunostomy kept the mortality low. Enteral nutrition should be started early. Laparostomy is a good way to manage retroperitoneal abscesses. To avoid delay, patients at risk of duodenal injuries should be evaluated early by experienced trauma surgeons and any central retroperitoneal haematoma should be explored during the initial laparotomy.

Blunt hepatic injury: minimal intervention is the policy of treatment

BACKGROUND

Many publications recommend nonoperative treatment for stable blunt hepatic injury patients. Unstable hemodynamic status is the only indication for surgery. When operation is indicated, controversies exist regarding which operative procedure will be more beneficial to the patients. The purposes of this study are to compare the results of operative and nonoperative management of patients with blunt hepatic injuries and to identify the optimal surgical approach when surgery is indicated.

METHODS

Different prospective protocols of treating adult blunt hepatic injuries were conducted. From 1992 to 1993 (group I), urgent surgery would be performed in the presence of hemoperitoneum. The policy shifted to aggressive nonoperative approach between 1996 and 1997 (group II). The patients from each period were divided into three subgroups. Group A included the patients who received nonoperative treatment in either period. Group B consisted of the patients who received surgery in the first period and nonoperative management in the second period. Group C included the patients who were operated on in either group. Comparisons were made between matched groups.

RESULTS

Groups IA and IIA patients had minor injuries and could be successfully treated nonoperatively. The results of groups IB and IIB were similar concerning hospital stay, morbidity, and mortality. Transfusion requirements of group IIB patients were significantly higher (2.2 vs. 1.1 units,p = 0.01) than those of group IB. However, 25 (58%) celiotomies of group IB patients were nontherapeutic. When surgery was indicated, group IC patients had significantly higher liver-related mortality (14 of 49 vs. 3 of 55, p = 0.002). Anatomic resection was performed more frequently in that period.

CONCLUSION

Nonoperative treatment significantly decreased the rate of nontherapeutic laparotomy but carried the risks of higher transfusion requirements and delaying operation. When surgery was indicated, the policy of minimal intervention positively affected the patients' outcomes. The goal of surgery should be hemorrhage control rather than resection of the injured liver tissues.

Cell count ratio: new criterion of diagnostic peritoneal lavage for detection of hollow organ perforation

OBJECTIVES

Diagnostic peritoneal lavage (DPL) had been widely used in evaluating patients with suspected intraperitoneal injuries due to its high sensitivity. If the positive criteria are strictly followed, however, the incidence of nontherapeutic laparotomies will be unacceptably high. This realization has become more important recently with the popularization of nonoperative treatment for blunt solid organ injuries. For these patients, the early diagnosis of an associated hollow organ perforation is mandatory.

METHODS

Three hundred and twenty patients undergoing DPL over an 18-month period were retrospectively reviewed to evaluate the usefulness of "cell count ratio" in diagnosing hollow organ perforation. The cell count ratio was defined as the ratio between white blood cell count and red blood cell count in the lavage fluid divided by the ratio of the same parameters in the peripheral blood.

RESULTS

Two hundred twelve patients were diagnosed as having a positive DPL according to the classic criteria. Forty-four patients (21%) had a cell count ratio of greater than or equal to 1. The diagnosis at laparotomy was small bowel perforation in 31 patients, colon perforation in eight patients, diaphragmatic hernia in one patient, pancreatic transection in two patients, and liver laceration in two patients. None of the patients with a cell count ratio of less than I sustained hollow organ perforation. The average interval from injury to DPL was 5 hours, with the shortest being 1.5 hours.

CONCLUSION

A cell count ratio of greater than or equal to 1 predicted hollow organ perforation with a specificity of 97% and a sensitivity of 100%. The selective use of the cell count ratio has improved the probability of early diagnosis of bowel perforation without increasing the cost of care. Nonoperative management can be applied more confidently to those patients sustaining a blunt solid viscus injury of the abdomen if the cell count ratio is low. We conclude that the cell count ratio of DPL effluent is a very sensitive and specific indicator of hollow organ perforation. In the treatment of blunt abdominal injuries, if the cell count ratio is positive, nonoperative treatment should be abandoned and a laparotomy undertaken.

Studies on Agrobacterium tumefaciens. VIII. Avirulence induced by temperature and ethidium bromide

When tumorigenic strains of Agrobacterium tumefaciens were subcultured at temperatures between 31.5 and 37 degrees C or in broth containing ethidium bromide, they lost their capacity to induce tumors in tomato plants. The sensitivities of curing virulence (tumorigenicity) depended on the density of the population of cells, fewer cells (100/ml) being more sensitive to curing than higher densities (10(6)/ml). The loss of virulence need not require the total loss of the virulence-specifying plasmid, but may result from a loss of a small segment of that plasmid. Virulent strains made avirulent by temperature or ethidium bromide treatment still harbor a large plasmid of 70-80 megadaltons size compared with the 100- to 120-megadalton plasmid in the untreated strains.

Blunt pancreatic trauma and pseudocyst: management of major pancreatic duct injury

When there is no major pancreatic duct injury or the injury involves only the distal duct, percutaneous drainage should be considered the primary therapeutic procedure for traumatic pancreatic pseudocyst. If the pseudocyst does not then resolve, endoscopic retrograde pancreatography should be performed to prove proximal duct injury. When the major pancreatic duct is disrupted but not obstructed, pancreatic duct stenting may avert surgical resection. If the major duct is obstructed, surgical resection is required.

Spurious hyperchloremia and decreased anion gap in a patient with dextromethorphan bromide

Although cold syrup containing dextromethorpan bromide is widely administered, the bromism due to cold syrup has not been reported. We report a patient who had negative anion gap with hyperchloremia and conscious loss because of daily intake of cold complex syrup (containing dextromethorphan bromide 0.4 mg/ml, acetaminophen 8.33 mg/ml) for headache for 4-5 years. The bromide content in cold complex syrup resulted in serum levels of bromide that interfered with the automated analyzers for chloride content. When conscious change is due to bromism, hemodialysis instead of forced hydration and diuresis should be performed immediately. Therefore, patients with a markedly negative anion gap with hyperchloremia should be considered as having halide intoxication.

Retroperitoneal laparostomy: an effective treatment of extensive intractable retroperitoneal abscess after blunt duodenal trauma

BACKGROUND

Delay in surgical treatment and duodenal wound dehiscence are two major causes of extensive retroperitoneal abscess formation after blunt duodenal injury. This complication is traditionally treated with primary repair of the duodenal wound and drainage of the abscess through anterior laparotomy. Pyloric exclusion is sometimes added as an adjunctive procedure. The anterior approach, however, may result in inadequate drainage, and repeat surgery is sometimes needed. We reviewed our experiences and evaluated the effectiveness of retroperitoneal laparostomy for the treatment of retroperitoneal abscess with continuous soiling.

METHODS

There were 52 blunt duodenal injuries during a 7-year period. Eleven patients developed extensive retroperitoneal abscesses.

RESULTS

All 11 patients were treated with anterior laparotomy initially. Five patients recovered after this procedure. Six patients continued to have retroperitoneal abscesses and were under septic status. Two patients received another anterior drainage, and had recurrent abscesses later. Retroperitoneal laparostomy was performed for these six patients. After retroperitoneal laparostomy, daily wound care, and antibiotic treatment, all six patients recovered. Only two patients developed incisional hernia.

CONCLUSION

Retroperitoneal laparostomy is effective in treating extensive intractable retroperitoneal abscess after blunt duodenal injury. Patients with the complications of duodenal leak and extensive retroperitoneal abscess should be treated with pyloric exclusion and drainage through anterior laparotomy first. If the duodenal wound does not heal after pyloric exclusion and retroperitoneal abscess persists, retroperitoneal laparostomy should be performed without further attempt to repair the wound.

Combined endoscopic and surgical treatment for the polyposis of Peutz-Jeghers syndrome

Repeated laparotomy with extensive small bowel resectioning and eventual short-bowel syndrome is a major problem in Peutz-Jeghers syndrome (PJS) patients. This problem is caused by gastrointestinal polyposis with intussusception. A combined surgical and endoscopic approach can assess the extent of the polyposis, and small polyps can be removed by snare polypectomy. This can avert multiple enterotomies and decrease bowel resection segments. We applied an intraoperative colonscope via the enterotomy route in an 20-year-old PJS woman, and successfully removed the other 10 polyps distributed in the whole small bowel. As part of an aggressive approach to the management of polyposis in PJS, complete polypectomy can provide a longer symptom-free interval and remove potentially premaligment polyps.

Computed tomography in left-sided and right-sided blunt diaphragmatic rupture: experience with 43 patients

AIM

To investigate differences in the radiographic signs for left and right-sided blunt diaphragmatic rupture (BDR) in order to provide guidance to avoid missing these injuries.

MATERIALS AND METHODS

A retrospective review of the computed tomography (CT) examinations of 43 patients with BDR treated at our hospital between January 1995 and 2007 was undertaken. The presence of diaphragmatic discontinuity, diaphragmatic thickening, herniation of abdominal organs into the thoracic cavity, collar/hump sign, dependent viscera sign, abnormally elevated 4 cm or more above the dome of the other-sided hemi-diaphragm, and of associated injuries was recorded and their relationship to each other and to BDR diagnosis examined. A comparison between the use of axial and sagittal/coronal reconstruction images in diagnosis was also performed in 15 patients.

RESULTS

On axial imaging, left-sided diaphragmatic rupture occurred in 31 patients (72%) and right-sided in 12 (28%). Twenty-nine patients had associated injuries. More than 60% of the patients showed the "dependent viscera" sign, "abdominal organ herniation" sign, diaphragm thickening, or had a more than 4 cm elevation of one side of the diaphragm. "Diaphragmatic discontinuity" and "stomach herniation" were seen almost exclusively in left-sided rupture. Those with BDR and haemothorax had a significantly lower incidence of "diaphragm discontinuity" (p=0.034) than those without haemothorax. Sagittal/coronal reconstruction slightly increased the number of band signs, diaphragmatic discontinuities and diaphragmatic thickenings seen.

CONCLUSIONS

Of the CT signs examined in this study, when herniation of abdominal organs was used as a diagnostic marker, only a very small fraction of trauma patients identifiable by CT would be missed. Further, CT signs differ for left-sided and right-sided BDR, thus the possibility of BDR should be considered when any of the reported CT signs are present.

HYPOTHALAMIC PARAVENTRICULAR NUCLEUS PLAYS A ROLE IN ACUPUNCTURE ANALGESIA THROUGH THE CENTRAL NERVOUS SYSTEM IN THE RAT

This work investigates the effect of hypothalamic paraventricular nucleus (PVN) on acupuncture analgesia in the rat. Electrical stimulation of PVN or injection of L-glutamate sodium into PVN could enhance the analgesic effect induced by acupuncture Zusanli (St. 36) while the electrical cauterization of PVN is decreased; Removal of the pituitary could not influence the effect of enhancing acupuncture analgesia induced by the injection of L-glutamate sodium into PVN. These results suggest that PVN might play an important role in acupuncture analgesia through central nervous system.

Spontaneous rupture of left external iliac vein: case report and review of the literature

Iliac vein rupture is rare and primarily results from major trauma or occurs during pelvic surgery. Spontaneous nontraumatic rupture is even more unusual, with only 14 cases reported in the literature. We report an additional case, summarize all of the cases, and discuss the possible causes and treatment of iliac vein rupture and the role of anticoagulants in postoperative management.

Surgical management of juxtahepatic venous injuries in blunt hepatic trauma

The purpose of this analysis was to understand better the problems faced in the management of blunt juxtahepatic venous injuries and to try and simplify the controversies regarding the optimal surgical approach to these injuries. Charts of 92 blunt liver trauma patients treated between July 1, 1991 to June 30, 1993 were reviewed. Nineteen patients with blunt juxtahepatic venous injuries were identified. The isolated left hepatic vein injury group (five patients) were all treated using a nonshunting approach with no mortalities. Half of the isolated right hepatic vein injury group (ten patients) received an atriocaval shunt, and the other half did not. These two different approaches each produced one survivor, with a combined mortality rate of 80% (eight of ten patients). One of the combined injuries group (four patients) received a total hepatectomy followed by liver transplantation. Another received a shunt. The other two were treated without shunting, but all of them expired. The overall mortality rate was 63.2% (12 of 19 patients), with nine patients dying intraoperatively or immediately postoperatively from exsanguination. The other three died 10, 25, and 30 days postoperatively because of sepsis. Juxtahepatic venous injury should be suspected after failure of the Pringle maneuver to stop bleeding and the different venous injuries differentiated by palpation of the adjacent hepatic parenchymal injuries. If an isolated left hepatic vein injury is found and the liver parenchymal injury is limited to segments II, III, or IV, then a nonshunting approach will achieve the optimal outcome.

Plasticity of tetramer formation by retinoid X receptors. An alternative paradigm for DNA recognition

Retinoid X receptors (RXRs) are transcription factors that traditionally have been thought to bind DNA as protein dimers. Recently, however, it has been recognized that RXRs can also bind to DNA as protein tetramers. Receptor tetramers form cooperatively on response elements containing suitably reiterated half-sites, and play an important role in determining the specificity of DNA recognition by different nuclear receptors. We report here that RXR tetramers exhibit significant functional plasticity, and form on response elements possessing diverse half-site orientations and spacings. This ability of RXRs to form tetramers and related oligomers appears to contribute to the synergistic transcriptional activation observed when multiple, spatially separated response elements are introduced into a single promoter. Oligomerization may therefore be a common paradigm for DNA recognition and combinatorial regulation by several different classes of transcription factors.

The influenza virus nucleoprotein synthesized from cloned DNA in a simian virus 40 vector is detected in the nucleus

We obtained DNA sequences coding for the nucleoprotein (NP) of an influenza A virus by reverse transcription of virion RNA with synthetic oligonucleotide primers. Terminal sequence analysis showed that the cloned gene contained a full-length copy of the virion RNA segment. The NP-specific DNA was inserted into the late region of a simian virus 40 vector, and the DNA recombinant was propagated in the presence of an early simian virus 40 temperature-sensitive mutant helper. Infection of African green monkey kidney cells with the recombinant produced a polypeptide immunoprecipitable with NP-specific antisera. The polypeptide product had a molecular weight of 56,000, identical to that of the nucleoprotein of influenza virus as estimated on polyacrylamide gels. The putative NP was detected in the nucleus of infected primate cells by an immunofluorescence assay. This nuclear localization of NP from recombinant DNA was similar to that seen during influenza virus infection.

Glycosylation and surface expression of the influenza virus neuraminidase requires the N-terminal hydrophobic region

A full-length double-stranded DNA copy of an influenza A virus N2 neuraminidase (NA) gene was cloned into the late region of pSV2330, a hybrid expression vector that includes pBR322 plasmid DNA sequences and the simian virus 40 early region and simian virus 40 late region promoters, splice sequences, and transcription termination sites. The protein encoded by the cloned wild-type NA gene was shown to be present in the cytoplasm of fixed cells and at the surface of "live" or unfixed cells by indirect immunofluorescence with N2 monoclonal antibodies. Immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis of [35S]methionine-labeled proteins from wild-type vector-infected cells with heterospecific N2 antibody showed that the product of the cloned NA DNA comigrated with glycosylated NA from influenza virus-infected cells, remained associated with internal membranes of cells fractionated into membrane and cytoplasmic fractions, and could form an immunoprecipitable dimer. NA enzymatic activity was detectable after simian virus 40 lysis of vector-infected cells. These properties of the product of the cloned wild-type gene were compared with those of the polypeptides produced by three deletion mutant NA DNAs that were also cloned into the late region of the pSV2330 vector. These mutants lacked 7 (dlk), 21 (dlI), or all 23 amino acids (dlZ) of the amino (N)-terminal variable hydrophobic region that anchors the mature wild-type NA tetrameric structure in the infected cell or influenza viral membrane. Comparison of the phenotypes of these mutants showed that this region in the NA molecule also includes sequences that control translocation of the nascent polypeptide into membrane organelles for glycosylation.

Blood glucose measurement by multiple attenuated total reflection and infrared absorption spectroscopy

The difficulty of measuring physiological concentrations of glucose in blood by conventional infrared absorption spectroscopy is due to the intrinsic high background absorption of water. This limitation can be largely overcome by the use of a CO2 laser as an infrared source in combination with a multiple attenuated total reflection (ATR) technique. To demonstrate the applicability of this technique, we compared in vitro measurements of glucose in blood obtained from an experimental infrared laser spectrometer with independent measurements made by a standard YSI 23A laboratory glucose analyzer. The capability of continuous measurement of blood glucose concentration is of primary importance in the future development of a glucose sensor for diabetic patients.