Pancreas divisum: thin-section CT

Twelve patients with known pancreas divisum underwent thin-section computed tomography (CT) to determine the capability of CT to depict this pancreatic anomaly. Focal pancreatic enlargement was present in five patients. Two distinct pancreatic moieties separated by a fat cleft were noted in three patients; a fourth patient had focal atrophy in the distribution of the dorsal pancreas. The two pancreatic moieties were identified at the same craniocaudal level in all four of these patients. The dorsal duct was depicted in all 12 patients, while the short ventral duct was seen in only five of the 12 patients. Failure of the ventral and dorsal pancreatic ducts to fuse was identified in all five patients in whom both ducts were seen. CT may not enable specific diagnosis of pancreas divisum in the majority of patients. If, however, distinct pancreatic moieties or unfused ductal systems are evident, the diagnosis may be confidently suggested.     

FM sonography in diffuse liver disease: prospective assessment and blinded analysis

FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.     

Mechanisms and treatment of postoperative ileus

OBJECTIVE: To review the pathogenesis and treatment of postoperative ileus. DATA SOURCES: Data collected for this review were identified from a MEDLINE database search of the English-language literature. The exact indexing terms were "postoperative ileus," "treatment," "etiology," and "pathophysiology." Previous review articles and pertinent references from those articles were also used. STUDY SELECTION: All relevant studies were included. Only articles that were case presentations or that mentioned postoperative ileus in passing were excluded. DATA SYNTHESIS: The pathogenesis of postoperative ileus is complex, with multiple factors contributing either simultaneously or at various times during the development of this entity. These factors include inhibitory effects of sympathetic input; release of hormones, neurotransmitters, and other mediators; an inflammatory reaction; and the effects of anesthetics and analgesics. Numerous treatments have been used to alleviate postoperative ileus without much success. CONCLUSIONS: The etiology of postoperative ileus can best be described as multifactorial. A multimodality treatment approach should include limiting the administration of agents known to contribute to postoperative ileus (narcotics), using thoracic epidurals with local anesthetics when possible, and selectively applying nasogastric decompression.     

Preliminary Outcome Analysis in Patients With Breast Cancer and a Positive Sentinel Lymph Node Who Declined Axillary Dissection

Background:This retrospective study was designed to provide a preliminary outcome analysis in patients with positive sentinel nodes who declined axillary dissection.Methods:A review was conducted of patients who underwent lumpectomy and sentinel lymph node excision for invasive disease between January 1998 and July 2000. Those who were found to have sentinel lymph node metastasis without completion axillary dissection were selected for evaluation. Follow-up included physical examination and mammography.Results:Thirty-one patients were identified who met inclusion criteria. Primary invasive cell types included infiltrating ductal carcinoma, infiltrating lobular carcinoma, and mixed cellularity. Most primary tumors were T1. Nodal metastases were identified by hematoxylin and eosin stain and immunohistochemistry. Twenty-seven of the metastases were microscopic (<2 mm), and the remaining four were macroscopic. All patients received adjuvant systemic therapy. With a mean follow-up of 30 months, there have been no patients with axillary recurrence on physical examination or mammographic evaluation.Conclusions:We have presented patients with sentinel lymph nodes involved by cancer who did not undergo further axillary resection and remain free of disease at least 1 year later. This preliminary analysis supports the inclusion of patients with subclinical axillary disease in trials that randomize to observation alone.     

The Synthesis and Enzymatic Polymerization of Nucleotides Containing Mercury: Potential Tools for Nucleic Acid Sequencing and Structural Analysis

A simple acetoxymercuration reaction for introducing covalently bound mercury atoms into nucleotides is described. The 5-mercuriacetate derivatives of UTP, CTP, dUTP, and dCTP, as well as the 7-mercuriacetate derivative of 7-deazaATP, have been prepared by this procedure and tested as substrates for nucleic acid polymerases. These nucleotides, in the absence of added mercaptan, are not polymerized and in most instances are potent enzyme inhibitors. However, conversion of these mercuriacetates to mercurithio compounds in situ by the addition of one of various mercaptans, yields nucleoside triphosphates that are excellent substrates for all polymerases tested: Escherichia coli and T7 RNA polymerases, DNA polymerase I of E. coli, DNA polymerase of avian myeloblastosis virus, and calf-thymus terminal deoxynucleotidyl transferase. By varying the mercaptan used to promote syntheses it is possible to access certain structural limitations in the enzyme's nucleoside triphosphate binding site. These mercurinucleotides appear to have a diversity of potential applications: (1) as heavy-atom reagents for crystallographic and microscopic studies; (2) as affinity probes for enzymes sensitive to sulfhydryl modification; (3) as steric probes of substrate-binding sites on enzymes; and (4) as reagents for forming covalent protein-polynucleotide complexes.     

Role of oxyradicals in cold water immersion restraint-induced gastric mucosal injury in the rat

Cold water immersion restraint of the rat results in focal gastric mucosal erosions. The lesions are associated with powerful, prolonged-duration gastric contractions. Phasic gastric contractions may attenuate gastric mucosal blood flow, resulting in ischemia followed by reperfusion. Therefore, the conditions of cold-water-immersion restraint might lead to mucosal injury by an oxyradical-mediated mechanism. To test this hypothesis, we studied the effect of oxyradical inhibition on cold water immersion restraint-induced lesions. In separate groups of rats subjected to cold water immersion restraint (6-10 animals per group), oxyradical inhibition was achieved by chronic feeding of a sodium tungstate diet, oral administration of allopurinol, or intraperitoneal administration of dimethylsulfoxide. None of these regimens significantly attenuated the number of lesions per stomach, the total lesion area, or the percent of corpus mucosa containing lesions. We conclude that oxyradicals do not play a role in the pathogenesis of cold water immersion restraint-induced lesions.     

Chemotherapy for advanced thymoma. Preliminary results of an intergroup study

OBJECTIVE: To determine the efficacy of combination therapy with cisplatin, doxorubicin, and cyclophosphamide alone or with radiotherapy for patients with extensive and those with limited unresectable thymoma. DESIGN: Nonrandomized, prospective phase I-II trial. SETTING: A Cooperative Oncology Group trial involving tertiary medical centers. PATIENTS: Twenty of twenty-two patients with measurable, extensive or limited, unresectable thymoma were evaluable for response. INTERVENTION: Patients were given cisplatin, 50 mg/m2 body surface area, doxorubicin, 50 mg/m2, and cyclophosphamide, 500 mg/m2, on day 1, with cycles repeated every 21 days until progression or until the maximally tolerated total doxorubicin dosage (for example, 450 mg/m2) was reached. Intravenous hydration with normal saline was administered during treatment courses. For responding patients with limited disease, 4500 cGy was administered to primary tumors after the second cycle of chemotherapy and before the initiation of the third cycle. MEASUREMENTS AND MAIN RESULTS: Three complete and eleven partial remissions were seen in 20 evaluable patients, for a total response rate of 70% (95% CI, 46% to 88%). The median duration of remission was 13 months with three patients remaining continuously disease free for over 2 years. The median survival time of all eligible patients was 59 months (CI, 22 months to infinity). Four patients developed infections, including listerial and aseptic meningitides, mucocutaneous candidiasis, and cryptococcal pneumonia, that were indicative of a defect in cell-mediated immunity. CONCLUSIONS: Combination therapy with cisplatin, doxorubicin, and cyclophosphamide frequently produces objective remissions in patients with advanced thymoma. Further experience with this treatment regimen is warranted to clarify potential prognostic factors in patients with unresectable thymoma.     

Bone marrow failure after hemorrhagic shock

The proliferation of white blood cells is an important and necessary response to bacterial infection. The effect of hemorrhagic shock and LPS administration on myelopoiesis was investigated. Rats subjected to hemorrhagic shock and resuscitation were injected IP with 100 micrograms E. coli LPS or saline 24 hr following shock. Twenty-four hours later, myelopoiesis was assessed by the growth of granulocyte-macrophage progenitor cells (CFU-GM) in both bone marrow (BM) and spleen (SPL). CFU-GM were cultured in the presence of no additional serum or normal rat serum or shock serum obtained 6 hr after hemorrhage. Shock resulted in a peripheral leukocytosis although BM and SPL cellularity was unaffected by either shock or LPS. BM and SPL CFU-GM from unshocked rats significantly increased after LPS administration (BM 47 +/- 6 vs. 70 +/- 8; SPL 40 +/- 4 vs. 72 +/- 14; both P less than 0.05). Shock had no effect on BM or SPL CFU-GM. In contrast, LPS given to shocked rats decreased BM CFU-GM compared to saline-treated rats (50 +/- 3 vs. 34 +/- 4 P less than 0.05). The addition of normal serum to the culture system had no effect on BM CFU-GM but the addition of shock serum reduced CFU-GM by 50% in all groups (P less than 0.05). These data demonstrate that shock markedly alters the myelopoietic response to LPS and may also result in the production or release of inhibitors of CFU-GM growth.     

Biomarkers of periodontal inflammation in the Australian adult population

Background:  Several inflammatory biomarkers are implicated in the pathogenesis of periodontitis including interleukin-1β (IL-1β) and C-reactive protein (CRP). This study investigated the presence of these factors in gingival crevicular fluid (GCF) and their relationship to clinical and social determinants of periodontitis in the Australian population.
Methods:  Equal numbers of periodontitis cases and non-cases were sampled during oral epidemiologic examination in the National Survey of Adult Oral Health. GCF was sampled from four sites where probing pocket depth (PPD) and recession were recorded. From these, IL-1β and CRP were quantified by ELISA and the log amount of GCF IL-1β (pg) per person and the proportion of adults with detectable CRP was computed.
Results:  Periodontitis cases (n = 511) had significantly higher levels of IL-1β and CRP than non-cases (n = 562). PPD, clinical attachment loss, plaque and gingivitis indices were positively associated with elevated levels of both biomarkers. Levels of both were positively associated with age, low socio-economic position and non-Australian birth.
Conclusions:  The presence of IL-1β and CRP in GCF are associated with periodontal disease parameters within the Australian population. The levels of both biomarkers are influenced by age, education and eligibility for public dental care.