Paraganglioma of the pancreas: literature review and case report

Extraadrenal paragangliomas are very rare tumors arising from cells derived from the neural crest. These tumors are encountered only as case reports, and as a result, little is known of their natural history. We present a case of pancreatic paraganglioma and review all previously reported cases.

Expression of complement regulatory proteins-CD 35, CD 46, CD 55, and CD 59-in benign and malignant endometrial tissue

OBJECTIVE

Complement system plays an important role in host defense mechanisms against microorganisms and tumor cells. To protect themselves from autologous complement-mediated damage, normal host tissues express cell membrane-associated complement regulatory proteins (CRPs). To investigate whether neoplastic endometrial tissues overexpress these proteins to escape complement damage, we examined the distribution of complement receptor type 1 (CR1, CD35), membrane cofactor protein (MCP, CD46), decay-accelerating factor (DAF, CD55), and protectin (MACIF, CD59) on frozen endometrial tissue samples.

METHODS

A total of 54 endometrial tissue samples were collected. Cryosections were obtained of 31 benign and 23 malignant tissue specimens. Tissue sections were stained by immunohistochemical staining procedure using specific antibodies and employing the avidin-biotin technique. Quantitation of the protein content of these CRPs was determined using the Samba 4000 image analysis system.

RESULTS

For all four of the CRPs studied, a statistically significant difference in protein expression between the benign and malignant endometrial tissue specimens (P < 0.0001) was observed.

CONCLUSIONS

Overexpression of all the CRPs studied (CD35, CD46, CD55, CD59) was observed in the malignant as compared with the benign endometrial tissues. The upregulation of these CRPs may promote resistance of the endometrial malignant tissue to complement-mediated damage, thereby allowing the tumor cells to escape from cytolysis and thus promoting carcinogenesis.

Immunologic and virologic responses to HAART in severely immunocompromised HIV-1-infected children

OBJECTIVE

To determine the long-term immunologic and virologic effects of highly active antiretroviral therapy (HAART) in children with AIDS.

DESIGN

A prospective observational study.

SETTING

Two pediatric HIV clinics.

PARTICIPANTS

Twenty-five protease-inhibitor naive HIV-infected children (aged 2-18 years) with advanced disease (CD4 < or =6%).

INTERVENTION

HAART (one protease inhibitor and one or more nucleoside analogs). Diphtheria and tetanus immunization in six patients after 18 months of therapy.

MAIN OUTCOME MEASURES

Changes in percentage of CD4 cells and plasma HIV-1 RNA levels; post-treatment assays of lymphoproliferative responses to recall antigens; CD4 cell memory phenotype.

RESULTS

Median duration of follow-up was 18.8 months (range, 7.5-28 months). At baseline the CD4 cell percentage was 2% (range, 0-6%), this increased significantly to 16% (range, 3-48%) above baseline at 12 months (P = 0.002). The mean maximum CD4 cell increase was 20.7% (range 4-48%) which corresponds to 657x10(6) cells/l (range, 30-2240x10(6) cells/l) above baseline. By contrast, the median viral load was not significantly lower at 12 months than at baseline (P = 0.34), and only 25% of the patients had sustained undetectable viral load. Of the reconstituted CD4 cells 70% were naive, and none of the subjects had lymphoproliferative responses to tetanus and diphtheria although 40% did develop responses to Candida, an environmental antigen. A single immunization with diphtheria and tetanus toxoid produced lymphoproliferative responses to tetanus in three out of six patients.

CONCLUSIONS

HAART was associated with sustained increases in CD4 cell counts, despite a high incidence of 'virologic failure'. CD4 counts and the proportion of naive cells were higher than have been reported in adults, which may be a reflection of greater thymic activity in children. Memory cell clones for antigens encountered in the past which are not prevalent before therapy could not be expanded without additional antigenic exposure.

The german thorotrast study: recent results and assessment of risks

The German Thorotrast study comprises 2,326 patients and 1,890 controls. Forty-eight Thorotrast patients and 239 controls are still alive and are invited for a follow-up examination every 2 years. In the deceased patients, the following neoplastic diseases with excess rates were registered (Thorotrast/controls): liver cancer (454/3); cancer of the bile ducts, including gallbladder (42/7); myeloid leukemia (40/7); myelodysplastic syndrome (30/4); plasmacytoma (10/2); non-Hodgkin's lymphoma (15/5); bone sarcoma (4/1); malignant peritoneal or pleural mesothelioma (9/0). Dose calculations are based on results of whole-body counting, X-ray films, and data obtained from the hospital records on the volume of Thorotrast injected. For liver cancer, the cumulative risk estimate was calculated to be 40 per 10(4) person Sv (radiation weighting factor = 20). These figures are close to the results of the Danish study and are comparable to the results of the Life Span Study of A-bomb survivors after 40 years at risk with 18 to 48 liver cancers per 10(4) person Sv. For hematopoietic malignancies, the cumulative risk was calculated to be about 7 per 10(4) person Sv (radiation weighting factor = 20). This risk estimate is lower by a factor of 10 compared to the results of the Life Span Study.

Predictors of the severity of acute pancreatitis in patients with HIV infection or AIDS

We retrospectively reviewed the charts of 54 human immunodeficiency virus (HIV) infected patients or acquired immunodeficiency syndrome (AIDS), who were hospitalized at the Bronx-Lebanon Hospital Center with acute pancreatitis between January 1993 and December 1995. Nineteen were female and 35 were male patients. Thirty-five (65%) of 54 patients were younger than 40 years (average age, 42 years). Forty-eight (89%) of the patients had a CD4 count of <200 units/ml of blood. Seventeen (32%) patients died either of complications of acute pancreatitis or of underlying disease. The conventional prognostic criteria used to assess the severity of pancreatitis, including Ranson's and Imrie's criteria and the APACHE II system, were applied. We determined that these criteria were not appropriate to our HIV/AIDS patients. Only serum calcium levels at 48 h after admission and serum creatinine and blood urea nitrogen (BUN) at admission and at 48 h after admission had significant p values (<0.05). We believe that the predictors commonly used to identify the severity of pancreatitis were not useful in these patients because of their low CD4 counts and preexisting liver and renal disease.

Initial experience with day case laparoscopic cholecystectomy at a tertiary care hospital in India

BACKGROUND

Cholecystectomy is one of the commonest general surgical operations. Laparoscopic cholecystectomy is currently the most favoured approach. As it is associated with less postoperative pain and ileus, it allows early discharge of patients from the hospital. Studies from the West have reported that 'day case laparoscopic cholecystectomy' is feasible and safe. In India, the current practice is to admit patients for laparoscopic cholecystectomy 24-48 hours prior to surgery and to discharge most patients within one to two days of surgery. There is no report from any Indian centre describing 'day case laparoscopic cholecystectomy'. We conducted a prospective study to assess the feasibility, safety and patients' acceptance of 'day case laparoscopic cholecystectomy' in a tertiary care hospital.

METHODS

Eighty-four patients with symptomatic cholelithiasis, aged less than 65 years with ASA grade I and II, were offered day case laparoscopic cholecystectomy. Seventy-four patients consented to be included in the study. The nature of operation and likely postoperative course were explained in detail to the patients. Conventional 4-port laparoscopic cholecystectomy was attempted in all patients. The main outcome measures assessed were successful management of patients on day case basis and its acceptance by the patients.

RESULTS

Sixty-eight (92%) patients underwent successful laparoscopic cholecystectomy. Fifty-five of these (81%) were successfully managed as day case procedures. There were no major complications. Three of the 55 patients (5.4%) needed re-admission and could be managed conservatively. Fifty-three (96%) patients described their experience as 'pleasant'. None of them described their experience to be 'unpleasant' or 'bad'. Fifty-four (98%) patients stated that they would recommend day case laparoscopic cholecystectomy to close friends and relatives.

CONCLUSION

In selected patients, day case laparoscopic cholecystectomy is safe and feasible in a developing country.

Lobular carcinoma-in-situ within a fibroadenoma of the breast

We present a case of an in-situ lobular carcinoma within an otherwise benign fibroadenoma in a 45-year-old woman.

Continuous foaming for protein recovery: part I. Recovery of beta-casein

Foam separation is known to have potential for separation of biological molecules with a range of surface activities. A statistical study (factorial design) was carried out to establish the optimum operating conditions for the continuous foam separation of beta-casein. Maximum values of enrichment of beta-casein into the foam phase were found for low levels of initial feed protein concentration, gas flow rate, feed-flow rate, and high foam heights. Maximum values of protein recovery, were generally found at high levels of initial feed protein concentration, gas-flow rate, feed-flow rate, and low foam heights. The highest values obtained for enrichment and separation ratio were 54.7 and 181.3, respectively, with a simultaneous protein recovery of 62%; thus, illustrating the potential effectiveness of this technique. The effect of foaming on protein conformation is also important, and in this study protein structure was analyzed before and after foam separation experiments. Techniques used were: native polyacrylamide gel electrophoresis (PAGE), UV absorbance spectroscopy, circular dichroism, and fluorescence. Native PAGE showed no detectable changes in protein structure. However, absorbance scanning, fluorimetry, and circular dichroism revealed some conformational changes over a range of concentration effects.

Continuous foaming for protein recovery: part II. Selective recovery of proteins from binary mixtures

Foam separation may have potential for protein recovery. However, for foam separation to be a viable protein recovery technique it is important to demonstrate, not only that high enrichments and recoveries can be achieved for single proteins, but also that high enrichments and recoveries, together with selectivity of partition, can be achieved for recovery from multi-component mixtures. Most process streams which require purification are indeed complex multi-component mixtures, for example, fermentation broths. In this study, three binary protein mixtures were chosen for continuous foam separation: beta-casein:lysozyme; Bovine serum albumin (BSA):lysozyme and beta-casein:BSA (mixtures 1, 2, and 3, respectively). For each of these mixtures, the expected outcome of each experiment, based on a previous knowledge and determination of relevant protein physical properties, was that the first protein should be preferentially separated into the foam phase. On the basis of results reported in Part I of this study for the continuous foam separation of beta-casein, conditions found to favor maximum enrichment were selected. For each mixture a range of concentrations of both proteins was considered. For mixture 1, maximum protein recoveries in the foam phase were 85.6% and 25% for beta-casein and lysozyme, respectively; and for mixture 2, maximum recoveries of 77. 6% and 18.9% were obtained for BSA and lysozyme, respectively. Maximum enrichment ratios in the foam phase were 79.4 and 2.5 for beta-casein and lysozyme respectively in mixture 1; and 74.0 and 1.4 for BSA and lysozyme respectively in mixture 2. Selective partitioning of beta-casein and BSA into the foam phase was obtained in mixtures 1 and 2, respectively, particularly for protein concentrations at which dilute protein films are known to form at the gas-liquid interface in the foam. Maximum partition ratios for mixtures 1 and 2 were 31.8 and 52.8, respectively. For mixture 3, both BSA and beta-casein were enriched into the foam phase. Maximum enrichments were 42.9 and 24.7 for BSA and beta-casein, respectively; however, selective partitioning in mixture 3 was limited (maximum partition ratio being 1.8).

Polyphenols inhibit promotional phase of tumorigenesis: relevance of superoxide radicals

Ellagic acid (EA), tannic acid (TA), caffeic acid (CA), and ferulic acid (FA) offer considerable promise as anticarcinogens. The role of these dietary polyphenols was investigated in the promotional phase of carcinogenesis. Topical application of polyphenols simultaneously with phorbol-12-myristate-13-acetate (PMA) or mezerein resulted in significant protection against 7,12-dimethyl-benz[a]anthracene-induced skin tumors in mice. Caffeic acid was the most effective inhibitor of tumor promotion. In vivo and in vitro treatment of murine peritoneal macrophages with the tumor promoters resulted in stimulation of superoxide anion radical formation. Tannic acid, caffeic acid, and ferulic acid were stronger inhibitors of PMA- and mezerein-induced superoxide anion radical than ellagic acid in in vivo and in vitro conditions. Treatment of [1(3)-14C]glycerol- or [methyl-14C]choline chloride-labeled resident or thioglycollate-elicited macrophages with PMA and mezerein led to accumulation of radioactive diacylglycerol equivalents. The polyphenols were capable of inhibiting these releases.

Gastrointestinal manometry studies in children

Children with gastrointestinal motility disorders present with diverse symptoms, and obtaining a detailed history is often impossible. As in adults, evaluation of a suspected motility disorder begins with exclusion of mechanical obstruction or primary inflammatory disorders. Subsequently, coordination of peristaltic function is evaluated in those segments of the gastrointestinal tract that are suspected to be abnormal based on the clinical history. Evaluation of gastrointestinal motility in children is particularly challenging because of frequent lack of patient cooperation and difficulties in adapting the equipment to patient size. This review discusses the indications and approach to the evaluation of motility of each region of the gastrointestinal tract in infants and children.

Normal limits of 14C-urea breath test

BACKGROUND/AIMS

14C-urea breath test has been widely used for diagnosis of Helicobacter pylori (H. pylori) infection. There is no general agreement on the cutoff values for determination of H. pylori negative subjects. We studied baseline values in subjects who were proved to be H. pylori negative and calculated the cutoff value of normalcy. A comparison of this test with other tests for diagnosis of H. pylori infection was also done.

PATIENTS AND METHODS

12 patients (mean age 34 +/- 14, range 22-65 years; 8 men) of non-ulcer dyspepsia were studied, who were proved to be H. pylori negative by rapid urease test, Gram's staining, histopathology and culture of gastric mucosal biopsies obtained four each from the antrum, body and fundus of the stomach. The controls included 12 patients (mean age 40 +/- 13, range 22-65 years, 9 men), who were positive for H. pylori on culture or combination of rapid urease test and histopathology or rapid urease test and Gram's stain. 14C-urea breath test was performed using 5 uCi of 14C-urea dissolved in 300 ml of water. Breath samples were collected once before ingestion of 14C urea and subsequently at 5, 15 and 30 minutes after ingestion and 14C-contents in the breath samples measured. Results were expressed as 14 CO2/mmol CO2 exhaled as percent of administered urea.

RESULTS

The mean +/- SD 14-C value in H. pylori negative vs H. pylori positive patients at 5 minutes, 15 minutes and 30 minutes were found to be 0.003 +/- 0.003 vs 0.064 +/- 0.042 (p < 0.001), 0.002 +/- 0.001 vs 0.056 +/- 0.039 (p < 0.001) and 0.001 +/- 0.002 vs 0.041 +/- 0.026 (p < 0.001) respectively. The mean values of 14C-urea breath test were significantly lower in H. pylori negative patients as compared to H. pylori positive patients. Using receiver operating characteristic (ROC) analysis of the data, the cutoff values obtained were 0.01, 0.007 and 0.009 at 5 minutes, 15 minutes and 30 minutes respectively.

CONCLUSIONS

14C-urea breath test levels at 5, 15 and 30 minutes intervals are significantly lower in H. pylori negative patients as compared to H. pylori positive patients. This test has high sensitivity and specificity in detecting H. pylori infection.

Protein recovery using gas-liquid dispersions

Two separation techniques, foam separation and colloidal gas aphrons (CGAs), both of which are based on gas-liquid dispersions, are compared as potential applications for protein recovery in downstream processing. The potential advantages of each method are described and the concentration and selectivity achieved with each method, for a range of proteins is discussed. The physical basis of foam separation is the preferential adsorption of surface active species at a gas-liquid interface, with surface inactive species remaining in bulk solution. When a solution containing surface active species is sparged with gas, a foam is produced at the surface: this foam can be collected, and upon collapse contains surface active species in a concentrated form. CGAs are microbubble dispersions (bubble diameters 10-100 microm) with high gas hold ups (>50%) and relatively high stability, which are formed by stirring a surfactant solution at speeds above a critical value (typically around 5000 rpm). It is expected that when proteins are brought into contact with aphrons, protein adsorbs to the surfactant through electrostatic and/or hydrophobic forces. The aphron phase can be separated easily from the bulk solution due to its buoyancy, thus allowing separation of protein in a concentrated form.

Intraoperative radiofrequency microbipolar coagulation to replace incisions of maze III procedure for correcting atrial fibrillation in patients with rheumatic valvular disease

OBJECTIVE

Radiofrequency catheter ablation of atrial tachycardias and flutter is an established technique. The same modality in the microbipolar mode is effective in producing full thickness coagulation injury. Cox's maze procedure is highly successful in curing atrial fibrillation (AF) surgically. However, it consumes relatively long cross clamp time and cardiopulmonary bypass time. In this study, radiofrequency microbipolar coagulation was used as an adjunct to corrective valve surgery, as an intraoperative ablative modality to replace Cox's maze III incisions, thus remarkably shortening the procedure. The results of this procedure are compared historically with those of 26 patients who underwent corrective valve surgery alone.

METHODS

Radiofrequency microbipolar coagulation was used to produce conduction blocks along the Cox's maze III incision lines as an adjunct to valve surgery in 18 patients in atrial fibrillation undergoing surgery for rheumatic valvular disease. A bayonet type bipolar forceps with an active tip length of 7 mm drawing current from a microbipolar port of Valleylab Force 4 electrosurgical unit (Valleylab, Boulder, CO) was used for microbipolar coagulation. A 3-mm retinal handheld cryoprobe working on nitrous oxide gas was used for cryoablation.

RESULTS

A total of 15 survivors in the coagulation maze group were followed from 43 to 224 days (149.7 +/- 73.1 mean +/- S.D.). Twelve of the 15 survivors (80%) converted to normal sinus rhythm (70% confidence limit: 64.7-90.6%). Atrial transport function studies with pulsed wave doppler, showed presence of a wave in all the 12 (100%) patients in tricuspid valve flow and in nine (75%) patients in mitral valve flow. The procedure took 11.62 +/- 3.86 min of elective cardioplegic arrest time for the left atrial portion and 18.71 +/- 4.25 min of cardiopulmonary bypass time during reperfusion for the right atrial portion. Of the 23 survivors out of 26 patients who underwent the valve procedure alone, only one patient (4.3%) converted to normal sinus rhythm (70% confidence limit: 0.6-14%).

CONCLUSION

Thus, our modification considerably shortened the time taken for creating the maze in comparison to the Cox's maze procedure and was effective in restoring normal sinus rhythm in 80% of the patients.

Effective doses to members of the public from the diagnostic application of ionizing radiation in Germany

The exposure of the German population to man-made radiation results mainly from diagnostic X-ray and nuclear medical examinations. Data are presented about the annual frequency and the average dose of the various examination types for West Germany in the years 1990-1992. According to these data a yearly average of approximately 1550 diagnostic examinations using ionizing radiation were performed per 1000 inhabitants resulting in an annual per caput effective dose of 1.9 mSv. Despite the frequent use of alternative examination techniques, such as sonography, nuclear magnetic resonance and endoscopy, the frequency of X-ray and nuclear medical examinations is still increasing. If collective risk assessments are done using the per caput effective dose, at least the age distribution of the patients must be considered. This leads to a "risk-modifying factor" of 0.6-0.7 for patients to be applied to the ICRP risk coefficient of 5 % per Sv valid for the general population. However, radiation risk must always be viewed in context with disease- and therapy-related risks and balanced against the benefit of the diagnostic examination, which should always exceed the risk for a well-indicated procedure.

Development of experimental model of chronic pyelonephritis with Escherichia coli O75:K5:H-bearing Dr fimbriae: mutation in the dra region prevented tubulointerstitial nephritis

Escherichia coli that express Dr fimbriae and related adhesins recognize the common receptor decay accelerating factor. E. coli strains that express adhesins of the Dr family were postulated to be associated with cystitis (30-50%), pregnancy-associated pyelonephritis (30%), and chronic diarrhea (50%). In this study, we investigated the hypothesis that E. coli renal interstitial binding mediated by the Dr adhesin may be important for the development of chronic pyelonephritis. An insertional dra mutant, E. coli DR14, of the clinical E. coli isolate IH11128 bearing Dr fimbriae, was constructed and used to characterize persistence of infection and interstitial tropism in an experimental model of ascending pyelonephritis. Quantitative cultures of kidney homogenates indicated that Dr hemagglutinin positive (Dr+) E. coli IH11128 established a 1-yr colonization of renal tissue. In the Dr hemagglutinin negative (Dr-) group, 50% of animals cleared infection within 20 wk and 100% between 32 to 52 wk. Dr+ E. coli colonized the renal interstitium. Significant histological changes corresponding to tubulointerstitial nephritis including interstitial inflammation, fibrosis, and tubular atrophy were found in the kidney tissue of the Dr+ but not the Dr- group. A substantial amount of fimbrial antigen was detected in the parenchymal regions affected by interstitial inflammation and fibrosis. The obtained results are consistent with the hypothesis that mutation within the dra region, affecting E. coli binding to tubular basement membranes, prevented renal interstitial tropism and the development of the changes characteristically seen in tubulointerstitial nephritis.

Estrogen regulation of lactoferrin expression in human endometrium

PROBLEM

Lactoferrin is an iron-binding glycoprotein that has been shown to be overexpressed in human endometrial carcinomas. The purpose of our present study is to investigate the possible role of estradiol in the expression of lactoferrin.

METHOD OF STUDY

We investigated 1) serum levels of lactoferrin in five women during normal ovulatory cycles, 2) serum levels of lactoferrin during ten human menopausal gonadotropin induced cycles when estradiol levels are high, and 3) lactoferrin expression in five proliferative and five secretory phase endometrium by immunohistochemical studies. The serum concentrations of lactoferrin were measured by a peroxidase-based enzyme-linked immunosorbent assay.

RESULTS

In normal ovulatory cycles, the mean serum lactoferrin concentration during the proliferative phase (0.4013 +/- 0.0242 micrograms/mL) was significantly higher (P < 0.02) than in the secretory phase (0.3468 +/- 0.0209 micrograms/mL). In induced cycles, there was gradual increase in lactoferrin levels with increasing estradiol concentrations. Peak lactoferrin levels in induced cycles (0.7495 +/- 0.1148 micrograms/mL) were significantly higher (P < 0.003) than the midcycle levels (0.423 +/- 0.0424 micrograms/mL) in normal cycles. Immunohistochemical analysis of the endometrium revealed greater expression of lactoferrin in proliferative endometrium (50.7 +/- 13%, range 28-72%) than in secretory endometrium (19.2 +/- 4%, range 7-31%).

CONCLUSION

These results indicate that estradiol may play a role in the regulation of lactoferrin expression in human endometrium.

Dexamethasone in bacterial meningitis: to use or not to use?

Permanent neurologic disabilities are seen in up to a quarter of survivors of bacterial meningitis despite major improvements in therapy. Experimental studies have demonstrated that most of the pathology in meningitis is mediated by inflammatory cytokines such as tumor necrosis factor (TNF) and interleukin-1 (IL-1), which are produced by host cells in response to bacterial invasion of the meninges. Dexamethasone has been used in a number of clinical trials to moderate the host response and to improve neurologic outcome of meningitis. Results of six randomized, placebo controlled trials are summarized in this review. Dexamethasone treatment did not lower mortality. Only a moderate, but not a significant reduction in the neurologic and audiologic sequelae was seen in dexamethasone recipients when Haemophilus influenzae type b (Hib) was the causative agent of meningitis. Following routine use of Hib vaccine, meningitis caused by this agent has virtually disappeared in the USA. Hence, findings from these trials may no longer be applicable in countries with high rates of immunization against Hib. Presently, there is little or no evidence showing a benefit of dexamethasone therapy in meningitis caused by S. pneumoniae or N. meningitidis. Global emergence of penicillin and cephalosporin resistant S. pneumoniae has raised new concerns about the use of dexamethasone in pneumococcal meningitis. Since dexamethasone significantly decreases the penetration and concentration of vancomycin and ceftriaxone in the CSF and delays CSF sterilization, adjunctive dexamethasone therapy may increase the risk of treatment failure in meningitis caused by antibiotic resistant pneumococci. An antibiotic combination should be used in the treatment of meningitis caused by antibiotic resistant pneumococci, particularly if dexamethasone is also being administered concurrently.