Porewater dynamics of silver, lead and copper in coastal sediments and implications for benthic metal fluxes

To determine the conditions that lead to a diffusive release of dissolved metals from coastal sediments, porewater profiles of Ag, Cu, and Pb have been collected over seven years at two contrasting coastal sites in Massachusetts, USA. The Hingham Bay (HB) site is a contaminated location in Boston Harbor, while the Massachusetts Bay (MB) site is 11 km offshore and less impacted. At both sites, the biogeochemical cycles include scavenging by Fe-oxyhydroxides and release of dissolved metals when Fe-oxyhydroxides are reduced. Important differences in the metal cycles at the two sites, however, result from different redox conditions. Porewater sulfide and seasonal variation in redox zone depth is observed at HB, but not at MB. In summer, as the conditions become more reducing at HB, trace metals are precipitated as sulfides and are no longer associated with Fe-oxyhydroxides. Sulfide precipitation close to the sediment-water interface limits the trace metal flux in summer and autumn at HB, while in winter, oxidation of the sulfide phases drives high benthic fluxes of Cu and Ag, as oxic conditions return. The annual diffusive flux of Cu at HB is found to be significant and contributes to the higher than expected water column Cu concentrations observed in Boston Harbor. At MB, due to the lower sulfide concentrations, the association of trace metals with Fe-oxyhydroxides occurs throughout the year, leading to more stable fluxes. A surface enrichment of solid phase trace metals was found at MB and is attributed to the persistent scavenging by Fe-oxyhydroxides. This process is important, particularly at sites that are less reducing, because it maintains elevated metal concentrations at the surface despite the effects of bioturbation and sediment accumulation, and because it may increase the persistence of metal contamination in surface sediments.

Short communication: presynchronization for timed artificial insemination in grazing dairy cows by using progesterone for 14 days with or without prostaglandin F2α at the time of progesterone withdrawal

Progesterone-containing devices can be inserted intravaginally for 14 d to presynchronize the estrous cycle for timed artificial insemination (TAI) in beef heifers ("14-day CIDR-PG" or "Show-Me-Synch" program). The progesterone treatment is effective for presynchronization because cattle develop a persistent dominant follicle during treatment that ovulates within 3 d after progesterone removal. The subsequent estrous cycle can be effectively used for a TAI program. Some cattle will retain a functional corpus luteum (CL) for the entire 14-d treatment period and will not be synchronized effectively because the interval to ovulation depends on the lifespan of their existing CL. The objective was to test the effect of a luteolytic dose of PGF(2α) at progesterone removal for improving synchrony of estrus after treatment and increasing conception rate to a subsequent TAI in dairy cows. Postpartum cows (n = 1,021) from 2 grazing dairy herds were assigned to 1 of 2 presynchronization programs that used a controlled internal drug releasing (CIDR) device containing progesterone: 14dCIDR (CIDR in, 14 d, CIDR out; n = 523) or 14dCIDR+PGF(2α) (CIDR in, 14 d, CIDR out, and PGF(2α); n = 498). Cows were body condition scored (BCS; 1 to 5, thin to fat) and tail painted at CIDR removal. Paint score (PS) was recorded after CIDR removal [PS = 0 (all paint removed, indication of estrus), PS = 3 (paint partially removed), or PS = 5 (no paint removed; indication of no estrus)]. At 19 d after CIDR removal, all cows were treated with PGF(2α), 56 h later treated with GnRH, and then 16 h later were TAI. Treating cows with PGF(2α) at CIDR removal increased the percentage with PS = 0 within 5 d (58.1% vs. 68.9%; 14dCIDR vs. 14dCIDR+PGF(2α)). We found no effect of treatment, however, on conception rate at TAI (41.1% vs. 43.6%; respectively). The TAI conception rate increased with increasing BCS and was greater for cows that had PS = 0 within 5 d after CIDR removal. In summary, treating cows with PGF(2α) at CIDR removal increased the percentage of cows with all tail paint removed but did not increase percentage of pregnant cows after TAI.

Metabolism of 6-Mercaptopurine by Resistant Escherichia coli Cells

Coggin, Joseph H. (University of Chicago, Chicago, Ill.), Muriel Loosemore, and William R. Martin. Metabolism of 6-mercaptopurine by resistant Escherichia coli cells. J. Bacteriol. 92:446-454. 1966.-6-Mercaptopurine (MP) utilization as a source of purine in MP-sensitive and -resistant cultures of Escherichia coli was investigated. The label of MP-8-C(14) appeared in adenine and guanine of ribonucleic acid and deoxyribonucleic acid in sensitive and resistant cultures. Studies using MP-S(35) further demonstrated that the MP moiety was degraded, as shown by a rapid decrease in radioactivity from cells upon exposure to MP for 20 min. Enzymatic analysis showed that MP was converted to 6-mercaptopurine ribonucleotide (MPRP) by extracts derived from both sensitive and resistant cells. Resistant cell preparations, however, degraded MPRP to inosine monophosphate (IMP) rapidly when compared with analogue degradation by sensitive cells. Inosineguanosine-5'-phosphate pyrophosphorylase from resistant cells did not catalyze the synthesis of IMP from hypoxanthine when the cells were cultured in the presence of MP, but these enzyme preparations actively converted guanine to guanosine monophosphate (GMP). Pyrophosphorylase derived from resistant cells cultured in medium without MP catalyzed the conversion of hypoxanthine to IMP and also guanine to GMP. These observations suggest that inosine-guanosine-5'-phosphate pyrophosphorylase is composed of two distinct enzymes. The mode of resistance to MP in E. coli is related to an enhancement of the enzymatic degradation of MPRP to the pivotal purine intermediate, IMP.

PATHWAY FOR THE DISSIMILATION OF ITACONIC AND MESACONIC ACIDS

Brightman, Vernon (The University of Chicago, Chicago), and William R. Martin. Pathway for the dissimilation of itaconic and mesaconic acids. J. Bacteriol. 82:376-382. 1961.-Studies on the oxidation of itaconic and mesaconic acids by a Pseudomonas sp., adapted to utilize either of these acids as a sole carbon source, have provided evidence for a pathway converting both itaconate and mesaconate to succinate. A metabolic interconversion of itaconate, mesaconate, and citramalate has also been demonstrated by whole cell and cell-free enzyme studies. Succinate derived from methylene-labeled itaconate was found to be labeled in the inside carbon atoms, a fact which indicates that the branched chain compound was converted into a straight chain molecule by a shift of the methylene carbon (C-5) from the side chain of itaconate to a position between C-2 and C-3 in an, as yet, unknown straight chain intermediate prior to its conversion to succinate.

Magnetic resonance imaging and spectroscopy in Parkinson's disease

At present, conventional MR imaging shows no convincing structural changes in PD itself but may be useful in helping to distinguish PD from other neurodegenerative parkinsonian syndromes and from the occasional case of parkinsonism secondary to a focal brain lesion. MR spectroscopy may also provide useful information in distinguishing PD from disorders such as MSA. The general field of MR imaging and spectroscopy is evolving rapidly, and there are a number of areas in which we can expect new developments to provide relevant information. Novel pulse sequences may provide more information regarding substantia nigra pathology in PD. The use of MR as a tool to measure regional iron concentrations should provide more information regarding the relationship between iron accumulation and parkinsonian symptoms. MR spectroscopy provides a sensitive tool for the researcher to investigate in vivo the possible contribution of abnormalities in brain energy metabolism to the pathogenesis of PD. Spectroscopy also allows the assessment of other metabolite changes in PD, for example, providing for the evaluation of the potential importance of changes in regional brain glutamate content. Last, although not considered in the present review, functional MR imaging provides the potential to evaluate, in a noninvasive fashion, the role played by the basal ganglia in motor control and in cognition in normal individuals as well as in PD.

Endoscopic papillary balloon dilation vs. sphincterotomy for removal of common bile duct stones: a prospective randomized pilot study

BACKGROUND AND STUDY AIMS

Endoscopic sphincterotomy (EST) is the standard procedure for gaining access to the common bile duct for removal of bile duct stones. However, the procedure is associated with both short-term and long-term complications. Recent reports have described the use of endoscopic papillary balloon dilation (EBD) as an effective and safe alternative to EST. We conducted a prospective randomized pilot study to compare the efficacy and short-term complication rates of these two established methods for removing uncomplicated bile duct stones.

PATIENTS AND METHODS

Sixty patients were randomly assigned to receive either EST (n = 30) or EBD (n = 30) prior to removal of bile duct stones (maximum size 20 mm, maximum number five). The patient groups were comparable with regard to sex and age ratios, the size of the stones (EST: mean 10 +/- 4.7 mm; EBD: mean 7 +/- 3.5 min; not significant) and the numbers of stones (EST: mean 1.8 +/- 1.5 mm; EBD: mean 1.6 +/- 1.1 mm; not significant). EBD was carried out using a balloon-tipped biliary catheter (Maxforce, Microvasive, Boston, Massachusetts, USA) with a maximum diameter of 24 Fr for 45-60 s. Bile duct stones were removed using Dormia baskets or retrieval balloons, or both.

RESULTS

The two methods were successful in all patients studied. Subsequent stone removal was possible in all 30 patients after EST (100%) and in 23 of the 30 who underwent EBD (77%), respectively (P<0.01). After conversion to EST, complete bile duct clearance was also achieved in the remaining seven EBD patients. The mean duration for the whole procedure was 17 +/- 12 min for EST and 29 +/- 15 min for EBD (not significant). Complications (WHO grades 2-4) were observed in five of the 30 EST patients (three cases of mild pancreatitis, two of hemorrhage) and in nine of the 30 EBD patients (three cases of cholangitis, four of mild pancreatitis, and two of severe pancreatitis), showing a trend toward higher complication rates in the EBD group. Postintervention hyperamylasemia was observed in six patients (three in each group).

CONCLUSIONS

The results of this prospective randomized pilot study indicate that EST is superior to EBD in terms of stone removal, duration of the procedure, and complication rates. EST will therefore continue to be the standard procedure for stone removal in the near future. Further studies will be needed in order to compare the longer-term results with EST and EBD.

DNA-zytometrische Untersuchungen der Barrett-Mukosa

BACKGROUND

Barrett's esophagus predisposes to cancer development. The diagnosis of dysplastic precursor lesions is impaired by problems of subjectivity. In the present study, DNA ploidy results of patients with Barrett's esophagus were related to the grade of dysplasia and to the progress of the disease.

PATIENTS AND METHODS

In 61 patients with Barrett's esophagus, DNA ploidy was determined by image cytometry on imprints. All biopsies (n = 145) were histologically examined for dysplasia distinguishing between low- and high-grade dysplasia, and dysplasia-negative.

RESULTS

A significant correlation (p < 0.001) between DNA ploidy and the grade of dysplasia was found, with 81% euploid DNA results in biopsies negative for dysplasia and 86% abnormal DNA patterns in biopsies with high-grade dysplasia. The subgroup of low-grade dysplasia showed a heterogeneous DNA ploidy. It is important to note that nearly 20% of biopsies classified dysplasia-negative contained abnormal single cells or abnormal stemlines regarding DNA content. In several cases, suspect DNA results caused a modified reclassification of dysplasia, and there were cases in which patients negative for dysplasia but positive for abnormal DNA ploidy developed dysplasia later on.

CONCLUSION

In patients with Barrett's esophagus, DNA ploidy by image cytometry is a suitable additive method for histological evaluation of dysplasia. It seems to be helpful in identifying patients at risk, perhaps before the development of clear dysplasia.

Electrohydraulic lithotripsy treatment of gallstone after disimpaction of the stone from the duodenal bulb (Bouveret's syndrome)

A 75-year-old man with right upper quadrant abdominal pain was diagnosed by gastroscopy to have an impacted gallstone in the duodenal bulb. Using the polypectomy loop, the stone was extracted from the bulbus and mobilized into the stomach. After failure to remove the stone from the stomach as well as fragmentation by mechanical lithotripsy, electrohydraulic lithotripsy was used to break up the stone, parts of which passed spontaneously through the bowel. Thus, it was unnecessary to proceed with surgical enterolithotomy to remove, from the duodenal bulb, the impacted gallstone responsible for the gastric outlet obstruction.

[Treatment of Barrett esophagus with argon plasma coagulation with acid suppression--a prospective study]

26 patients with a Barrett's esophagus of at least 2 cm length (medium 4.9 cm) were treated with a combination of repeated argon-plasma-coagulation (APC) and a long-term acid suppression using proton pump inhibitors controlled by a 2 h pH monitoring. Eleven out of 26 patients (42%) showed endoscopically and histologically a complete eradication of the metaplastic cylindric epithelium (intention--to treat analysis). Nine patients (35%) had an endoscopic complete remission but remnants of the cylindric epithelium were found at the histologic examination. On an average one APC-session was necessary for 1 cm of initial length of the Barrett's esophagus. No serious complications were seen. It remains unclear if this therapy can reduce the long-term risks for adenocarcinoma of the esophagus in patients with Barrett's esophagus.

Ropinirole and pramipexole, the new agonists

Ropinirole and pramipexole are non-ergoline dopamine agonists which are relatively specific for the D2 family of dopamine receptors. They have side-effect profiles linked to peripheral and central dopaminergic stimulation, amenable to tolerance through a slow titration or the addition of domperidone in sensitive patients. They do not have the uncommon but problematic ergot-related side effects of bromocriptine and pergolide. Ropinirole and pramipexole have both been shown to be efficacious when used as monotherapy in early Parkinson's disease (PD), and have been suggested as being less likely than levodopa to lead to the early development of motor fluctuations and dyskinesias in this clinical setting. They have also been shown to be useful as adjunctive therapy to levodopa in advanced PD and to have a levodopa-sparing effect in these patients. Dose equivalents amongst the available dopamine agonists is difficult to know with certainty but has been estimated as follows: 30 mg of bromocriptine, 15 mg of ropinirole, 4.5 mg of pramipexole, and 3.0 mg of pergolide.

The prevalence of motor neurone disease in the Province of Alberta

Using data from the Alberta Health Care Insurance Plan, the prevalence of motor neurone disease (MND) was estimated for the Province of Alberta, Canada. Between January 1, 1994 and December 31, 1995, 208 cases of MND (125 males, 83 females) were identified from physician billing records giving a period prevalence of 7.38 (8.9 for males, 5.9 for females) per 100,000 population. On prevalence day, July 1, 1995, there were 171 cases (103 males, 68 females) of MND giving a point prevalence estimate of 6.07 (7.3 for males, 4.8 for females) per 100,000 population. Males were more likely to be diagnosed (OR = 1.52, 95% CI 1.1, 2.1) with MND and there was an increased risk of receiving a diagnosis with increasing age (chi 2trend = 281, p < 0.001). The mean age of the cases was 59.2 years (58.5 for males, 60.3 for females) and did not differ significantly between the sexes. Geographically, there was no statistically significant difference in the prevalence across regions of the Province. During the study period, 28% of the cases had died (30% of males, 25% of females). The prevalence of MND in Alberta, is among the highest reported in the literature and requires additional investigation to verify these estimates and identify possible causative factors.

Wrestling

Wrestling is considered one of the most physically demanding sports among high school and college athletics and, as such, has a proportionate number of injuries. Strength and endurance is paramount to successful performance. The wrestler needs to have not only strength and endurance, but also technical skill to be successful. Weight control and weight loss distinguish it from most other sports at the high school and collegiate levels. In addition to musculoskeletal problems, medical conditions and diseases impact the ability if the wrestler is to safely participate in this demanding but rewarding sport.

Prevalence and clinical importance of Helicobacter pylori infection in patients after partial gastric resection for peptic ulcer disease. A prospective evaluation of Helicobacter pylori infection on 50 resected patients compared with matched nonresected controls

There have been only a few surveys on the prevalence of persistent Helicobacter pylori (Hp) infection in patients who have undergone surgery for peptic ulceration. The aim of the study was to evaluate the prevalence and clinical importance of Hp infection after partial gastric surgery due to peptic ulcer disease.

METHODS

We examined 50 patients who had partial gastric resection for peptic ulcer disease and years later underwent upper gastrointestinal (GI) endoscopy. 50 controls matched with respect to indication for GI endoscopy, age and gender were also studied. Three specimens from the fundus of gastric remnant were examined for Hp infection (histology and rapid urease test). The prevalence of Hp infection and pathology findings were compared between the two groups using chi-square statistics.

RESULTS

32 men and 18 women were examined (40 x BII, 10 x BI). The prevalence of Hp infection was 38% in the resected group compared to 60% in the control group (p = 0.015). We found a significant association (p = 0.0004) between Hp infection and endoscopic findings in the control group but not in the group of partially resected patients (p = 0.66).

CONCLUSION

The prevalence of Hp infection in hospitalized patients with partial gastric resection is significantly lower than in matched controls. Hp infection does not play a significant pathogenic role in recurrent ulcer after partial gastric resection in these patients.

[Percutaneous transhepatic metal stents in therapy of bile duct stenoses]

Treatment of choice for obstructive jaundice of different origin is the percutaneous transhepatic placement of endoprostheses if the endoscopic access fails for technical or anatomical reasons. Expandable metallic stents are generally preferred to plastic endoprostheses because of higher patency rates. Purpose of this study was to retrospectively evaluate the clinical efficiency and the occlusion rates of percutaneous placed metallic stents in 39 patients with malignant and benign biliary obstruction and to compare the results to a review of the literature. Placement of the stents was successful in all cases. Patients were followed-up for a mean of seven months (1-42 months). 54% of the patients had recurrent jaundice after a mean period of seven months (1-38 months). 35% were treated with a second procedure. Since the occlusion rates of percutaneous transhepatic metallic stents increase after six months and follow-up in most studies is short the real occlusion rates must be expected to be higher than reported. Therefore and in view to the high costs indication for the use of metal stents in biliary obstruction should be carefully checked.

Long-term results (7 to 10 years) of endoscopic papillotomy for choledocholithiasis. Multivariate analysis of prognostic factors for the recurrence of biliary symptoms

BACKGROUND

The long-term outcome after endoscopic papillotomy is poorly defined. The aim of this study was to determine the long-term results of this method in the treatment of common duct calculi and to determine which prognostic factors are associated with the relapse of biliary symptoms.

METHODS

Between 1985 and 1988, 223 consecutive (149 women, mean age 67.9 years) patients underwent endoscopic papillotomy for duct stones; 127 had already undergone cholecystectomy or underwent this operation during the same hospitalization. Follow-up data were obtained retrospectively from the patients and patients' relatives and general practitioners.

RESULTS

The procedure was successful in 217 of 223 cases (97%), of which 203 were followed-up; 2 patients died in the first month after treatment (0.89%). Mean follow-up for the 201 patients was 6.2 years, during which 31 relapsed (15%). Three significant prognostic factors for late complications were identified in a multivariate analysis. The recurrence rate of biliary symptoms in patients who were left with an in situ gallbladder was 20.2%, and 11% for those whose gallbladder was removed (p = 0.04). Patients with a bile duct 15 mm or greater in diameter were more prone to recurrence of symptoms than those with a bile duct 10 mm or less in diameter (41% vs. 10%, p = 0.025) and were especially at higher risk to develop recurrent stones (19.5% vs. 4.9%, p = 0.019). Stone recurrence, but not biliary symptoms as a whole, was more frequent in patients with a peripapillary diverticulum (p = 0.035).

CONCLUSIONS

The long-term results of endoscopic papillotomy are comparable with those of surgical techniques. The prognostic factors associated with relapse of biliary symptoms as a whole are gallbladder left in situ and choledochal diameter. Bile duct size and peripapillary diverticula are associated with recurrent bile duct stones.

Suspected chromium picolinate-induced rhabdomyolysis

Rhabdomyolysis results from skeletal muscle injury and release of muscle cell contents into plasma. A number of etiologic factors have been reported for the condition, including strenuous exercise, weight lifting, trauma, seizure, sepsis, and alcohol and drug abuse. Hundreds of drugs also reportedly cause rhabdomyolysis. A 24-year-old body builder developed the disease after ingesting 1200 microg of chromium picolinate (6-24 times the daily recommended allowance of 50-200 microg) over 48 hours. We believe this to be the first reported case of chromium-induced rhabdomyolysis.

A new HF current generator with automatically controlled system (Endocut mode) for endoscopic sphincterotomy--preliminary experience

BACKGROUND AND STUDY AIMS

The main complications of endoscopic sphincterotomy are pancreatitis, hemorrhage, perforation and cholangitis. In a prospective randomized trial, a conventional current generator was compared to a new generator with an automatically controlled cut system (Endocut) for sphincterotomy. The purpose was to establish whether the new device reduces the complication rate of sphincterotomy. Our experiences over the last 2 years with the new HF current generator are described here.

PATIENTS AND METHODS

In this study 100 patients were randomly assigned to one of the two generators. The following points were documented in a protocol form: abrupt or continuous cutting; length of papillotomy; complications.

RESULTS

There were no significant differences in sex, age or indication for sphincterotomy. Nor were there any significant differences in the length of the sphincterotomy or mild pancreatitis. In contrast, an abrupt opening of the papillary roof was more frequently observed with the conventional generator (18 patients) than with the new device (one patient, P < 0.001). Mild bleeding occurred in two patients with the new unit, but in 13 with the conventional unit (P = 0.002). Moderate or severe bleeds were observed in neither of the two groups. During the subsequent application phase lasting for 2 years, the following complications occurred in a total number of 850 sphincterotomies (EST): pancreatitis 2.8% (one patient died); hemorrhages requiring transfusion 1% (n = 8); concealed perforations 0.3% (n = 3).

CONCLUSIONS

According to our experience to date and based on this study, this new HF surgery unit enables performance of controlled, bloodless sphincterotomies. The danger of papillary hemorrhage appears to be reduced. All examiners found the new system to be safer and more convenient.

[Barrett esophagus with severe dysplasia in argon beam therapy]

A curative therapy of Barrett's esophagus is not established, yet. However, in prospective clinical research trials, a combined therapy of potent pharmacological acid suppression with superficial coagulation of metaplastic epithelium is examined. By local coagulation using photodynamic therapy, laser or argon plasma coagulation, a complete reconstitution of squamous epithelium should be achieved. We report on a case of a patient with Barrett's esophagus and low-grade dysplasia, who developed high-grade dysplastic cell formations under argon plasma coagulation therapy. As part of a clinical study, the patient was treated over a period of one year monthly. We monitored the result of the therapy over the period of one year with endoscopy, histolgical investigations and DNA image cytometry. Ultimately a decision in favour of a further surgical management was made. The diagnostic instruments to identify patients with a high risk for the development of adenocarcinoma are discussed.

Increasing striatal iron content associated with normal aging

Free-radical-mediated mechanisms may contribute to neuronal damage in Parkinson's disease (PD), other neurodegenerative conditions also associated with aging, and the aging process itself. Cytotoxic free radicals are generated in the brain by oxidation/reduction reactions that are catalyzed by transition metals such as iron. Any regional increase in brain iron concentration may increase the potential for local free-radical formation. The purpose of this study was to determine the relationship between age and basal ganglia iron content in 20 normal individuals ranging from 24 to 79 years of age. We used an in vivo magnetic resonance method to quantify the effects of paramagnetic centers sequestered inside cellular membranes, thereby enabling the determination of a quantitative index of local brain iron content. We observed a strong direct relationship between age and regional iron content in the putamen (r = 0.76, p < 0.0001) and caudate (r = 0.69, p < 0.001), but not in the globus pallidus (r = 0.32, p = 0.17) or thalamus (r = 0.13, p = 0.58). In conclusion, striatal iron content increases with advancing age. This increase may increase the probability of free-radical formation in the striatum, therefore representing a risk factor for the development of neurodegenerative disorders such as PD in which nigrostriatal neurons may be affected by increased oxidant stress.

Increased basal ganglia iron in striatonigral degeneration: in vivo estimation with magnetic resonance

BACKGROUND

As many as 20% of individuals with the clinical diagnosis of Parkinson's disease (PD) do not have the characteristic neuropathologic features of PD at post mortem. The striatonigral degeneration (SND) subtype of multiple system atrophy is one of the categories of pathology which may be incorrectly diagnosed as PD on the basis of clinical presentation. SND may be associated with increased iron deposition in the putamen which can be detected with magnetic resonance imaging.

METHODS

We have estimated regional brain iron content in a patient with probable SND, using a novel imaging method developed in our laboratory, and have compared the results in this patient to those which we have previously reported in patients with PD and in age-matched controls.

RESULTS

We observed that putamenal iron content was increased in our SND patient, beyond the 95% confidence limit for inclusion in the PD group, even when considering clinical severity. In contrast, pallidal and thalamic iron were within the PD range.

CONCLUSIONS

The demonstration of increased putamenal iron content may be a useful adjunctive investigative procedure in patients with suspected SND.

Estimation of brainstem neuronal loss in amyotrophic lateral sclerosis with in vivo proton magnetic resonance spectroscopy

In vivo proton magnetic resonance spectroscopy (MRS) may be used to quantify brainstem neuronal degeneration in ALS because of the neuronal localization of N-acetylaspartate and N-acetylaspartylglutamate, together termed NA, which are estimated with this technique. We measured the ratio of NA to creatine/phosphocreatine (NA/Cr) with proton MRS at 3.0 tesla (T) in a 4.3-cm3 volume in the pons and upper medulla of 12 ALS patients and 17 age-matched control subjects. Brainstem NA/Cr was reduced in ALS versus control subjects (mean +/- SD: 1.57 +/- 0.20 versus 1.95 +/- 0.14; p < 0.0001). Patients with severe spasticity or prominent bulbar weakness had the lowest NA/Cr ratios; those with predominantly lower motor neuron limb weakness had near-normal ratios. We conclude that proton MRS may quantify region-specific neuronal dysfunction in ALS.

[Liver abscesses--complications after prosthesis and stent occlusions]

PURPOSE

Patients with malignant, unresectable biliary strictures and endoprosthesis or stents for drainage often develop liver abscess. The aim of the investigation was to assess the relationship and the factors causing the development of these abscesses.

METHOD

9 patients with a median age of 65.6 years, liver abscess and endoprosthesis or stents were studied retrospectively. The occlusions were made visible sonographically and by ERC or PTC. With sonography the abscess was diagnosed and punctured.

RESULTS

5 patients (56%) had a bile duct carcinoma, two patients had a distal tumor stenosis, one a tumor of the gallbladder and one an obstructive jaundice due to liver metastases. 8 patients required a percutaneous drainage (PTCD). 6 cases of occlusions were found. 1 patient had a biliary obstruction because of a broken endoprosthesis. On an average it took 11.6 months from the first endoprosthesis or stent placement to the formation of an abscess. Plastic endoprostheses tend to occlude more rapidly (5 months versus 17.6 with stents). After the sonographically guided puncture of the liver abscess, i.v. antibiotics were given for 5 to 14 days. The antibiotics were continued orally. Two cases required a sonographically placed percutaneous drainage. 78% of the abscesses could be cured. One patient died because of sepsis.

CONCLUSIONS

Liver abscesses were connected with intrahepatic carcinomas (56%). In such cases drainage is difficult and requires many interventions. Furthermore, we find this especially after percutaneous transhepatic drainage and with plastic endoprostheses.

Dysphagia secondary to left atrial dilatation

Dysphagia, of a cardiac origin, is a generally accepted, yet rarely diagnosed symptom. A 84-year-old female patient with left atrial dilatation, presenting with dysphagia and weight loss, was treated for global heart failure. Esophagography revealed compression of the distal esophagus. Echocardiography showed a left atrial, right atrial and right ventricular enlargement. Esophageal manometry revealed hypotonic peristaltic contractions of the esophageal body and a lower than normal resting pressure of the lower esophageal sphincter. After medical treatment for myocardial insufficiency and of esophageal motility, the clinical signs of global heart failure were improved and the dysphagia disappeared. Following the exclusion of common causes of dysphagia in patients with heart failure, dysphagia due to left atrial dilatation should be considered.

Fluoroscopically guided laser lithotripsy versus extracorporeal shock wave lithotripsy for retained bile duct stones: a prospective randomised study

BACKGROUND AND AIMS

To compare extracorporeal shock wave lithotripsy (ESWL) and laser induced shock wave lithotripsy (LISL) of retained bile duct stones to stone free rate, number of therapeutic sessions, and costs.

PATIENTS

Thirty four patients were randomly assigned to either ESWL or LISL therapy. The main reasons for failure of standard endoscopy were due to stone impaction (n = 12), biliary stricture (n = 8), or large stone diameter (n = 14).

METHODS

An extracorporeal piezoelectic lithotripter with ultrasonic guidance and a rhodamine 6G laser with an integrated stone tissue detection system were used. LISL was performed exclusively under radiological control.

RESULTS

Using the initial methods complete stone fragmentation was achieved in nine of 17 patients (52.4%) of the ESWL group and in 14 of 17 patients (82.4%) in the LISL group, or combined with additional fragmentation techniques 31 of the 34 patients (91.2%) were stone free at the end of treatment. In comparison LISL tended to be more efficient in clearing the bile ducts (p = 0.07, NS). Significantly less fragmentation sessions (1.29 v 2.82; p = 0.0001) and less additional endoscopic sessions (0.65 v 1.6; p = 0.002) were necessary in the LISL group. There were no major complications in either procedure.

CONCLUSIONS

Compared with ESWL, fluoroscopically guided LISL achieves stone disintegration more rapidly and with significantly less treatment sessions, which leads to a significant reduction in cost.

Management of esophageal perforations after therapeutic upper gastrointestinal endoscopy

BACKGROUND

Esophageal perforation is one of the most dreaded complications in therapeutic gastrointestinal endoscopy. We assessed the frequency of esophageal perforation after endoscopic procedures in a highly specialized endoscopy unit and compared clinical outcomes in patients undergoing either surgical or conservative management.

METHODS

From January 1985 to June 1996, 1011 instrumental endoscopic procedures (dilatation and bougienage) were performed in our department. The computerized complication database was searched to identify all patients with esophageal perforation during this same period, and their records were reviewed.

RESULTS

Seventeen esophageal perforations (1.7%) occurred in the course of 1011 procedures. Four perforations resulted from balloon dilatation, and 13 were secondary to bougienage. Six patients were managed surgically (35%), all of them recovering uneventfully. Eleven patients were managed conservatively, mainly because they were unfit for surgery. Survival rate in this group was 82%; only two patients died, both of whom had underlying malignant disease.

CONCLUSIONS

The current concept in management of esophageal perforations comprises surgical as well as medical treatment. In well-selected cases, non-operative treatment can be considered with favorable results.

Gender differences in adolescent psychiatric outpatient substance use: associated behaviors and feelings

OBJECTIVE

To investigate gender differences in substance use and associated high-risk behaviors and feeling states in 220 adolescent psychiatric outpatients.

METHOD

One hundred seven females and 113 males with a mean age of 15.6 (SD +/- 1.4), seen in a tertiary care center adolescent psychiatry clinic, completed scales tapping substance use and associated feelings and behaviors. Approximately half had used nicotine and alcohol, one third had used marijuana, and 10% reported narcotic use.

RESULTS

Conduct disorder behavior, suicidality, and impulsivity scale scores decreased with age in females while marijuana use, conduct disorder behavior, and Hypophoria scale scores increased with age in males. Alcohol use in males, as contrasted with females, correlated more significantly with other substance use and high-risk behaviors. Suicidality tended to correlate more with polysubstance use in females and with sexual behaviors in females only. Substance use correlated with the Impulsivity and Need scale scores in males and scores on the Sociopathy scale in females.

CONCLUSIONS

Substance use in males correlates with high-risk behaviors and is associated with feelings of impulsivity and need. Substance use correlates with self-destructive behaviors and sociopathic feelings in females. There is evidence of more persistent high-risk behaviors, including substance use, in males than in females.

[Endoscopic study of the small intestine with push enteroscopy. A prospective study]

OBJECTIVE

To evaluate whether push enteroscopy of the small bowel (PES), undertaken after extensive previous investigations in suspected intestinal bleeding from an uncertain site, chronic diarrhoea or lymphoma of the small intestine, contributes to the diagnosis, and to ascertain the results of PES and its clinical significance.

PATIENTS AND METHODS

56 consecutive patients (29 men, 27 women; mean age 63 years) were investigated prospectively. The main indications for PES were the search for the source of intestinal bleeding in 79% of patients (group A), chronic diarrhoea or tropical sprue in 16% (group B) and search for tumour of lymphoma in 5% (group C). PES was always performed in fasting patients under sedation/analgesia using a video PES, which contrary to catheter enteroscopy provides a channel for intervention.

RESULTS

In group A 27% of patients were found to have lesions, in particular angiodysplasias, or (in once case) leiomyoma. Half of these patients were successfully treated endoscopically without later surgical intervention being required (mean follow-up of six months). In the other half operation became necessary, either because the disease itself indicated it or the bleeding persisted, the source being in the more distant small intestine and thus not accessible to endoscopic intervention: only 50% of the length of the small intestine proved to be within reach of the instrument. No abnormalities were discovered in patients of groups B and C.

CONCLUSION

In cases of gastrointestinal bleeding from an uncertain source PES should be performed first, because in many cases it may obviate surgical intervention. But PES seems to contribute little of diagnostic value in other indications.

[Percutaneous and transpapillary laser lithotripsy of intrahepatic gallstones]

PROBLEM AND OBJECTIVE

In the last few years several intra- and extracorporeal endoscopic methods have been developed for treating intrahepatic gallstones, but as yet no ideal instrumentation has been found. This study was undertaken to test the efficacy and possible complications of intracorporeal laser lithotripsy for intrahepatic gallstones.

PATIENTS AND METHODS

16 consecutive patients were included (13 women and 3 men, median age 64 [28-82] years) with intrahepatic biliary tract stones which could not be removed by conventional endoscopy. A rhodamine-6G-laser with an integrated stone recognition system was used. The glass fibres of the laser instrument were introduced perorally or percutaneously and placed at the stone.

RESULTS

The percutaneous procedure under cholangioscopic control succeeded in four of the patients, while 12 were treated by a transpapillary approach (two under fluoroscopic, ten under cholangioscopic control). In eight of the latter group all stones were completely fragmented, i.e. 12 of the total were successfully treated. Of the remaining four patients two were cleared of stone by additional measures (extracorporeal shockwave lithotripsy and electrohydraulic lithotripsy, respectively), two were treated pallatively by endoprosthesis. One patient developed an acute cholangitis which was successfully treated with antibiotics and biliary drainage. There were no deaths.

CONCLUSIONS

Particularly when performed transcutaneously, laser lithotripsy provides effective treatment of intrahepatic gall stones. Cholangioscopic monitoring, to place the glass fibre at the stone, is usually required in the transpapillary approach.

[Long-term results of endoscopic balloon dilatation of ulcer-induced pyloric stenoses--follow-up of 25 patients]

Long-term results of the "through the scope balloon dilatation" for treatment of benign pyloric stenosis are lacking. Therefore we retrospectively analyzed 25 patients treated by balloon dilatation because of benign pyloric stenosis between 1986 and 1995. The mean age was 63 years (18-88 years), there were twelve men and 13 women. The mean follow-up period was 38 months (twelve to 120 months). 92% (23 patients) underwent successful dilatation. 20% (five patients) presented with recurrent obstruction. They were treated again and none of them has had symptoms up to now. There were no complications due to dilatation. Through the scope balloon dilatation is a successful and cost effective therapy for benign gastric outlet obstruction also in long-term follow-up.

Estimation of brain iron in vivo by means of the interecho time dependence of image contrast

An imaging protocol for a quantitative estimation of disease-induced variations in brain iron is proposed and then validated, first, on a phantom and second, on a group of 11 healthy volunteers. The relative estimate of brain iron is achieved from a rate difference image that measures the enhancement, delta R2app, of the transverse relaxation rate of water protons brought about by the heterogeneous accumulation of iron in the glial cells. At 1.5 T, the phantom study demonstrates, over the range 0-6 A/m, a linear dependence of delta R2app on the magnetization difference between microspheres and a paramagnetic gel, with a sensitivity of approximately 2 s-1 A-1 m. In the group of healthy volunteers (mean age 33 +/- 7 years) devoid of disease-related or appreciable age-related accumulations of iron, the precision of delta R2app was still sufficient to distinguish the globus pallidus and the putamen from all of the other iron-containing brain structures in a manner that was significant at the 99% confidence level.

Endoscopic stenting in obstructive jaundice due to liver metastases: does it have a benefit for the patient?

BACKGROUND/AIMS

The goal of this report is to describe our experience with the palliative endoscopic treatment of jaundice occurring in the setting of liver and hilar metastases of a distant primary malignancy.

MATERIAL AND METHODS

We retrospectively analyzed the clinical course of 29 consecutive patients with metastatic tumors not originating in the hepatobiliopancreatic area, who were treated by endoscopic retrograde cholangiopancreatography with endoprostheses insertion.

RESULTS

We achieved a complete follow-up in 24 out of the 29 patients (11 women, median age 69 years). The primary tumor site was the colorectum in 15 patients, stomach in 4, lung in 2, breast and prostate in 1 and one patient had a lymphoma. The median bilirubinemia before therapy was 16 (1.8-31) mg/dl and the median minimum serum bilirubin reached after stenting was 2.6 (0.3-11.5) mg/dl. Stent dysfunction was observed in 33.5% of the patients and stent change was necessary 13 times. The median survival after therapy was 4 (2.5-19) months for patients with colon tumors and 3 (0.5-12) months in patients with other cancers. An improvement in the quality of life was obtained in 75% of the patients after endoscopic treatment.

CONCLUSIONS

Endoscopic stenting should be attempted even on patients with obstructive jaundice due to liver metastases.

Basal ganglia iron content in Parkinson's disease measured with magnetic resonance

The possibility of using magnetic resonance (MR) to evaluate the severity of the pathological changes of Parkinson's disease (PD) is suggested by the known accumulation of iron in the basal ganglia in PD and the reduced signal evident from this area with conventional T2-weighted MR imaging. To improve the specificity of MR for the measurement of tissue iron content, we have developed a method that quantifies the effects of paramagnetic centers sequestered inside cellular membranes, based on the echo time dependence of the decay of transverse magnetization caused by the local field inhomogeneities which are due to intracellular iron. This method enables an index of local tissue iron content to be calculated for structures of the basal ganglia. We report here the application of this method to a series of patients with PD (n = 12) and of normal, age-matched controls (n = 13). Our objective was to determine whether this measurement of basal ganglia iron concentration correlates with the presence and severity of PD. We observed a significant increase in iron content in both the putamen and pallidum in PD as well as a correlation with the severity of clinical symptomatology. More severely affected patients had a higher iron content in both of these structures. Our results suggest that this MR measurement may provide a noninvasive method of measuring the severity of the pathological changes underlying PD.

-Bile duct stenoses and leakage after cholecystectomy: endoscopic diagnosis, therapy and treatment outcome-

Minimal invasive methods compete with surgical treatment in the therapy of complications after cholecystectomy. In this retrospective study we evaluate the efficacy of endoscopically placed biliary stents in 35 patients (25 female, ten male) with biliary strictures and/or leakage after cholecystectomy. 27 patients received a 10- or 11.5-French endoprosthesis, eight patients needed a percutaneous-transhepatic-cholangio-drainage (PTCD). Four patients (11.4%) underwent a surgical therapy. Endoscopic therapy was successfully completed in 23 patients (65.7%), at which we noticed a superior result in patients with early incidenced stenosis/leakages after cholecstectomy. During a follow-up period of 1-109 months (median 28 months) two recurrent strictures (5.7%) were observed. As a complication we have seen a prosthesis-dislocation after PTCD. None of the patients died of complications related to endoscopic therapy.

Brain-plasma distribution of free and total benzodiazepines in dogs physically dependent on different doses of diazepam

Steady-state levels of oxazepam (OX), nordiazepam (ND), and diazepam (DZ) in plasma, brain tissue, cerebrospinal fluid (CSF), and intracranial microdialysis perfusate were determined in dogs dependent on 0.56, 4.5, 9, and 36 mg/kg per day of DZ. There was a linear relationship between the total plasma and brain levels of DZ, ND, and OX and the chronic dose of DZ. Levels of free benzodiazepines in plasma and CSF and levels in microdialysis perfusates from plasma and brain were significantly correlated. With increasing dependence on DZ there was progressively more free ND and OX and less free DZ in plasma, CSF, and brain. There was a correlation between several signs of precipitated abstinence and free ND in the brain interstitial fluid, whereas convulsions emerged only when free metabolites exceeded free DZ. The changes in contribution of free DZ, ND, and OX to the overall levels of benzodiazepines present in the CNS may explain differences in signs of abstinence for different levels of dependence on DZ.

Generalized mitochondrial dysfunction in Parkinson's disease detected by magnetic resonance spectroscopy of muscle

OBJECTIVE

To explore mitochondrial dysfunction in Parkinson's disease (PD) using 31P magnetic resonance spectroscopy of resting muscle.

DESIGN

Case-control study (28 PD patients and 28 normal controls) determining resting forearm inorganic phosphate/phosphocreatine (Pi/PCr) ratio.

RESULTS

Significant difference (p = 0.004, one-tailed test) in Pi/PCr ratio between PD patients (0.122) and controls (0.104). No correlation of Pi/PCr ratio with duration, severity, or speed of onset of disease. Positive correlation of Pi/PCr ratio with age in control group; reversed in PD group.

CONCLUSIONS

Suggests small generalized mitochondrial defect in PD. The possibility that earlier onset of disease is associated with more severe mitochondrial dysfunction needs further study.

Functional caudate imaging in symptomatic Huntington's disease: positron emission tomography versus single-photon emission computed tomography

Functional neuroimaging with positron emission tomography previously demonstrated reduced caudate glucose metabolism in virtually all symptomatic patients with Huntington's disease (HD). Single-photon emission computed tomography studies of brain blood flow also have shown caudate abnormalities in patients with HD. The present study compared these two functional imaging modalities in 6 patients with HD who had been symptomatic for fewer than 5 years. All patients had significantly impaired caudate-thalamus and caudate-whole-slice glucose metabolism ratios as measured by positron emission tomography. However, only 3 had clearly abnormal caudate-thalamus activity ratios and 2 had clearly abnormal caudate-whole-slice ratios on single-photon emission computed tomography. These findings indicate that single-photon emission computed tomography imaging of caudate blood flow is a less sensitive indicator of caudate dysfunction in early HD than is positron emission tomography imaging of caudate glucose metabolism.