Die Kristall- und magnetische Struktur von BaCrF5 / Crystal and Magnetic Structure of BaCrF5

A single crystal X-ray structure analysis of orthorhombic BaCrF5 (a = 1393.8(1), b = 571,1(1), c = 494,7(1) pm), which crystallizes in the structure type of BaGaF5, space group P212121, yielded Cr-F distances in the range of 187.3 to 194.9 pm, average 190.2 pm. Using powder neutron diffraction data taken at 2.2 K a G-type antiferromagnetic structure with spin alignment along the c direction of the lattice was worked out. Single crystal susceptibility data were consistent with this model and in addition showed a small net moment, probably due to spin canting, to be present below the Neel temperature of TN = 3.4 K. The orientation of this moment along the b axis is in accordance with the space group symmetry as well, chemical and magnetic cell being the same. From powder susceptibility data an exchange energy of -3.74 K (g = 2.02) was obtained by fitting Fisher's model. The low bridging angle of Cr-F-Cr = 137.4° within the cis corner-sharing chain of octahedra is made responsible for the weak antiferromagnetism in BaCrF5, which is compared to that of other chromium(III) fluorides.

Fusobacterium nucleatum prosthetic hip infection in an adult with sickle cell-beta thalassemia

Fusobacterium nucleatum is an anaerobic Gram-negative bacillus commensal to the human oropharynx and gastrointestinal tract which causes an array of human infection, yet it has never been associated with infection of prosthetic joints. We report the first case of prosthetic hip infection caused by F. nucleatum in a man with sickle cell-beta thalassemia.

[Fatigue and icterus in a 27-year-old patient with diabetes mellitus type I]

We report about a 27-year-old female with type I diabetes who was admitted with progressive fatigue and a sudden onset of icterus. As the underlying cause, we found pernicious anemia with hemolytic activity as part of polyglandular autoimmune syndrome (PAS) type II. Under vitamin B(12) substitution we saw a quick rise in hemoglobin and improvement of complaints. Type I diabetes is the most frequent component of PAS II, whereas pernicious anemia is a rather rare component; however, a latent form is seen in about 12% of patients with type I diabetes. Therapy for pernicious anemia consists of parenteral vitamin B(12) substitution. Because of an increased incidence of gastric cancer in chronic atrophic gastritis, endoscopic follow-ups of the chronic atrophic autoimmune gastritis seem to be recommended. Due to the diverse characteristic of PAS II, with development of additional components after years of latency, regular follow-up clinical examinations and lab work are mandatory to detect further need of hormone and vitamin replacement that may sometimes be substantial for survival.

Quantitative atomic-scale analysis of interface structures: transmission electron microscopy and local density functional theory

Transmission electron microscopy (TEM) and local density functional theory (LDFT) are combined to analyze the microscopic structure of the rhombohedral twin interface in alpha-Al2O3. LDFT provides interfacial energetics and atomic and electronic structures for three competing models. With high-resolution TEM the atomic structure at the interface is imaged quantitatively along two orthogonal zone axes. Electron energy loss spectroscopy in TEM with nanoscale spatial resolution yields the interfacial electronic structure. Both experiments confirm the theoretically preferred model quantitatively.

Dissolution of gallbladder stones with methyl tert-butyl ether and stone recurrence: a European survey

Since there are now several ways to treat symptomatic gallstone disease, one is able to select treatment on the basis of the patient's comfort, the practicability, effectiveness, and side effects of the technique, and the relative costs. In order to assess the present status of contact dissolution with methyl tert-butyl ether with regard to these aspects, the present enquiry reports the data of 21 European hospitals. Eight hundred three patients were selected for contact litholysis of cholesterol gallbladder stones using methyl tert-butyl ether. Percutaneous transhepatic puncture of the gallbladder was performed under x-ray or ultrasound guidance. Dissolution rate, side effects, and treatment times of 268 patients from one single center were compared to those of 535 patients from the other 20 centers. Two hundred sixty-four patients were followed for five years to assess stone recurrence. Physicians were asked how they assessed the expenditure of the method, the discomfort to the patients, and the staffing situation. Patients were asked to indicate their acceptance on an analog scale. Puncture was successful in 761 (94.8%) patients. Prophylactic administration of antibiotics was not necessary. Stones were dissolved in 724 (95.1%) patients. In 315 (43.5%) sludge remained in the gallbladder. The most severe complication was bile leakage, which led 12 (1.6%) patients to have elective cholecystectomy. Toxic injuries due to the ether were not reported. Method-related lethality amounted to 0%, 30-day-lethality to 0.4%. Stone recurrence rate was about 40% in solitary stones and about 70% in multiple stones over five years. Patients with multiple stones developed recurrent stones almost twice as often as those with solitary stones. The probability of stone recurrence in patients with sludge in the gallbladder after catheter removal was not statistically significantly different from those without sludge. Seventy to 90% of the centers found the puncture to be simple and not distressing for patients and the relation between expenditure and therapeutic success to be acceptable. The acceptance of contact litholysis by the patients was excellent. Contact litholysis when applied by an experienced team provides real advantages in the treatment of gallstone disease. The method is technically simple, well accepted by the patients, and can be easily applied in community hospitals. Contact litholysis may be of particular value in patients who are not suitable for anesthesia or surgery.

[Role of bile acids in the development of peptic lesions. Studies on the bile acid-binding capacity of a new kind of antacid]

Bile acids are a factor in the pathogenesis of peptic lesions of the mucosa. The introduction in the literature of the term type C gastritis reflects the recognition of this fact. It is possible that antacids develop their effect not merely via the neutralization of hydrochloric acid, but, to an appreciable extent, through the adsorption of toxic substances. Since antacids often elevate the gastric pH only slightly, we investigated bile acid binding not only as a function of dose, but also at low pH values. The aim of the study was, in a follow-on to previous studies of a layer-lattice antacid to describe the characteristics of an antacid of the mixed type (aluminium-magnesium hydroxide + smectite). Already at neutral pH, Gelofalk manifests a high level of bile acid absorption, which increases further at low pH values. The high bile acid absorption capacity of Gelofalk shows no correlation with decreasing bile acid polarity; the dose-dependency is lower at high than at low pH levels. This indicates that bile acid absorption by Gelofalk must, at least in part, involve other mechanisms than those operative in the case of pure layer-lattice antacids.

[The effect of pH and amount of antacids on bile acid binding in a quasi-natural reflux milieu]

Bile acid adsorption may be one therapeutical mechanism of antacids. Little is known about the effect of pH and amount of antacid on bile acid adsorption. Therefore we carried out the following investigations using a lattice [correction of lettuce] layer antacid as a model substance. 5 ml of "quasi-natural reflux milieu" were mixed with 0.5, 1 or 2 ml of hydrotalcite and adjusted to pH 3, 5 or 7. The highest total bile acid adsorption was found at pH 3, the degree of bile acid adsorption correlated with bile acid lipophilicity, i.e. the most lipophilic and toxic bile acids are adsorbed best. High adsorption of lipophilic and particularly toxic bile acids even at low gastric pH may help to explain the good therapeutic effect of low-dose antacids in gastric ulcer.

[Endoscopy, shockwave lithotripsy and local lysis in complicated pigmentary calculi of extra- and intrahepatic bile ducts]

Endoscopy, extracorporeal shockwave lithotripsy (ESWL) and local lysis with alkaline solution of EDTA and bile salts in water were applied in combination in four patients with extra- and intrahepatic pigment stones as well as calcium bilirubinate covered concrements of the biliary tract. In the first patient (a man aged 80 years) a giant concrement of the bile duct was broken up after ESWL by three weeks of local chemical lysis and the fragments were removed by endoscopy. In the second case (man, aged 72), a nonextractable pigment stone was at first reduced in size by four-day local lysis and then removed endoscopically. Intrahepatic pigment stones were completely removed in the other two patients (boy of 12, man of 62) by local lysis only in 3 and 15 weeks, respectively. Even long-term use of the alkaline solution may not cause any serious side effects. Breaking up of stones after size reduction with ESWL of giant stones, size reduction of intact stones and contact lysis of intrahepatic stones are three important indications for chemical dissolution of biliary tract stones, respectively.

Ursodeoxycholic acid in primary biliary cirrhosis: results of a controlled double-blind trial

We studied the effect of ursodeoxycholic acid on 18 women and 2 men with primary biliary cirrhosis, mainly stages I and II. After a 3-mo observation period, patients were randomized to a 9-mo treatment period with ursodeoxycholic acid, 10 mg/kg.day, or placebo. Two patients on placebo left the study. In all patients on ursodeoxycholic acid, mean values of serum glutamate dehydrogenase, aspartate and alanine aminotransferases, alkaline phosphatase, and gamma-glutamyl transpeptidase fell significantly by 48%-79% after 18-24 wk; 7 of 10 showed a mean decrease of 35% in immunoglobulin M after 24 wk. Prothrombin time, serum bilirubin, albumin, the antipyrin breath test, and plasma disappearance of indocyanine green were normal initially and did not change. Total serum bile acid concentrations increased; ursodeoxycholic acid became the predominant bile acid. No significant improvement occurred in the placebo group. Hepatic histology improved in 6 patients of the ursodeoxycholic acid group but deteriorated in 4 patients receiving placebo. In studies with erythrocyte membranes, changes in electron spin resonance revealed that ursodeoxycholic acid was less toxic than chenodeoxycholic or deoxycholic acid, and coaddition of ursodeoxycholic acid prevented their toxic effect.

[Oral and direct lysis of gallbladder calculi. Competing or complementary procedures to shockwave lithotripsy?]

Non-surgical treatment of cholesterol gallstones is possible with oral chemolitholysis employing chenodeoxycholic acid (CDA) and/or ursodeoxycholic acid (UDA), oral chemolitholysis following ESWL and direct dissolution with methyl tert-butyl ether (MTBE). Oral chemolitholysis takes a long time (6-24 months), is suitable only for small stones (up to 1.5 cm) and has a success rate of 60-70%. Prior ESWL shortens the duration of oral treatment moderately and can be employed with larger (up to 3 cm) stones; it is, however, quite expensive. The new method of direct chemolysis of gallstones is rapid, very cheap, and effective (approx. 95% success rate), but is an invasive procedure. If previous results obtained with MTBE are confirmed, it could become a therapeutic alternative to cholecystectomy in the case of very large and multiple stones.

[Bile acid binding by antacids in a "quasi-natural" reflux milieu]

In a "quasi-physiological" reflux mixture obtained from non-stimulated gastric juice and hepatic bile the bile acid adsorption of 7 antacids is investigated with an newly developed HPLC method. The antacids produce pH values varying from 3.7 to 7.6. With increasing pH and increasing polarity of bile acids the bile acid binding to antacids decreases. The theoretically desirable combination of high pH and good bile acid binding is difficult to achieve. The relatively good total bile acid binding (over 60%) by Trigastril at a high pH (7.53) contrast with better bile acid adsorption by Maaloxan and Aludrox (about 90%) at a lower pH (4.5-4.9). Interestingly, toxic nonpolar bile acids are particularly well adsorbed by antacids.

Stimulation of rat sciatic nerve regeneration with pulsed electromagnetic fields

The effects of pulsed electromagnetic fields (PEMF) on rat sciatic nerve regeneration after a crush lesion were determined. The rats were placed between a pair of Helmholtz coils and exposed to PEMF of frequency 2 Hz and magnetic flux density of 0.3 mT. A 4 h/day treatment for 3-6 days increased the rate of nerve regeneration by 22%. This stimulatory effect was independent of the orientation of the coils. Exposure times of 1 h/day-10 h/day were equally effective in stimulating nerve regeneration. Rats exposed to PEMF for 4 h/day for 7 days before crush, followed by 3 days after crush without PEMF, also showed significantly increased regeneration. This pre-exposure 'conditioning' effect suggests that PEMF influences regeneration indirectly.

Dissolution of gall stones with an ursodeoxycholic acid menthol preparation: a controlled prospective double blind trial

In a controlled prospective double blind trial patients with cholesterol gall bladder stones are treated with ursodeoxy-cholic acid (group A: UDCA 11.1 mg/kg per day; n = 16) and Ursomenth respectively (group B: a mixture of UDCA/menthol: 4.75 mg/kg per day each; n = 17). With same stone number and size (10-12 mm) there is a complete dissolution rate in group A of 38%, and of 53% in group B within 15-16.9 months. The response rate (complete + partial dissolution) amounted to 75% and 76% respectively. In group A there is one case of stone calcification, in group B none. Both preparations are free of unwanted effects. This suggests that the cyclic monoterpene menthol enhances the effect of UDCA and is of comparable effect to a mixture of six different terpenes used in former times.

[Percutaneous transhepatic lysis of gallstones using methyl tert-butyl ether. Report on 15 patients]

In 15 patients (13 women and two men) with cholesterol stones in the gall-bladder a special (Thistle) catheter was introduced into the gall-bladder under local anaesthesia by percutaneous transhepatic puncture. Methyl-tert-butyl ether, 2-15 ml, was injected via the catheter and removed again after 2 min. The number of stones per gall-bladder averaged 6.3 (1-20), size of stones 1.7 cm (0.5-2.8 cm), and duration of treatment 11.9 h (5-24 h). The stones dissolved in 13 patients (87%). In three patients stone débris remained: in one it was ultimately sucked out after reduction of the amount of débris with an EDTA-containing solution. The side effects of treatment--nausea and vomiting--were minor. In one patient there was a leak of bile from the gall-bladder after the procedure; a cholecystectomy was uneventfully performed. Another patient developed haemobilia which responded to conservative treatment. MTBE treatment has thus proved to be a successful and cheap method, low in side effects, in the treatment of patients with gall-stones.

Endoscopy of the gallbladder as control of gallstone therapy with methyl-tert-butyl ether

We report on a 36-yr-old woman with six gallstones measuring 2.1 cm each. Within 21 h of methyl-tert-butyl ether (MTBE) treatment, the stones had dissolved to a small amount of residue. As could be seen from cholesterol concentrations of samples of aspirated gallbladder bile and MTBE fractions, the dissolution process was slow to begin with, and gained momentum during hours 6-11, after which it decelerated. We discontinued treatment after 20 h, since the stone residue showed no change. Cholecystoscopy performed with an Edwards angioscope via a catheter showed that there were no stone remnants, but that there were flat polyps on the gallbladder wall. One hour later, we stopped the therapy. Cholecystoscopy is a useful method of assessing the results of MTBE treatment.

[Alagille syndrome, a rare differential diagnosis of intrahepatic cholestasis]

In Alagille's syndrome cholestasis is caused by a congenital hypoplasia of the intrahepatic bile ducts. If cardiac and arterial malformations are present in conjunction with the typical-but not pathognomonic-facies, this rare syndrome must be considered. ERCP shows a highly rarified bile duct system. Liver histology with a paucity of interlobular bile ducts establishes the diagnosis. Inheritance appears to be autosomal dominant. The relatively good prognosis of the disease calls for caution concerning invasive procedures.

Prostaglandin E2 directly protects isolated rat gastric surface cell membranes against bile salts

Rat gastric surface cell membranes were prepared and the effect of taurocholic acid assessed by ESR spectroscopy using the 16-doxylstearic acid spin label. Taurocholic acid increased the polar part of the spectra, indicating an augmented amount of spin label molecules with a polar environment. Concomitantly, mobility of the spin label molecule was augmented. The effect of taurocholic acid was completely prevented by the previous addition of prostaglandin E2. This suggests a direct protective efficiency of prostaglandin E2 on rat gastric surface cell membranes without the metabolic participation of intact cells.

Diurnal rhythm of bile lipid composition after cholecystectomy and papillotomy. Postpapillotomy biliary lithogenicity

The influence of the gallbladder and the sphincter of Oddi on the diurnal rhythm of bile lipid composition was assessed by determining the lithogenic index at 4-h intervals over a period of 24 h in 29 cholecystectomized and papillotomized patients with a nasobiliary tube receiving a normal hospital diet and in 9 during 1-day fast. With a normal diet, biliary cholesterol concentrations dropped during the daytime (p less than 0.05), and total biliary lipid, bile acid, phospholipid, and cholesterol concentrations rose at night (p less than 0.05). During fasting, total biliary lipid, phospholipid, and cholesterol concentrations rose continuously (p less than 0.01). Even with loss of function of the gallbladder and sphincter of Oddi, a diurnal rhythm of biliary lithogenicity persisted, caused mainly by cholesterol increases during fasting. Concomitant increases in phospholipids and, to a lesser extent, bile acids modulated these changes.

Gallstone dissolution with ursodeoxycholic acid in patients with chronic active hepatitis and two years follow-up. A pilot study

Chemical dissolution of cholesterol gallstones using ursodeoxycholic acid (UDCA) in six patients with histologically confirmed HBsAg-negative chronic active hepatitis was started after a minimum of one year of therapy with steroids, azathioprine, or chloroquine and a treatment-free period of 8-15 months. The treatment with UDCA lasted 3-20 months with a daily dose of 8-11 mg/kg. Four patients served as controls. A decrease in transaminases (P less than 0.05) occurred in all patients during the UDCA therapy. After completion of the treatment, the figures rose again, but did not return to the initial value. The stones dissolved in five patients. A second liver biopsy was carried out in two patients after UDCA therapy, and this showed no detectable deterioration. Four patients refused biopsy because the laboratory parameters had improved under UDCA. A stone recurred in one patient six months after the end of therapy; the others have remained free of stones for up to 24 months.

[Blood flow measurement in esophageal varices using an endoscopic Doppler ultrasonic probe]

A new ultrasound Doppler probe allows endoscopic measurement of blood flow in oesophageal varices. First investigations in 6 patients show that the measurements are easy and well reproducible. Velocity of blood flow depends on respiration. Cephalad flow increases during inspiration. Caudalad flow may be enhanced by expiration and decreased by inspiration. Cephalad and caudalad blood flow in the same varix may point to drainage by a perforating vein. During and after endoscopic sclerosing, changes in blood flow can be demonstrated. This method gives us the possibility to assess blood flow in oesophageal varices not only for pathophysiological studies, but also for planning and control of sclerosing therapy.

Sex differences in rat liver bile acids

Male Wistar rats show higher relative liver weights and higher weights of mitochondrial and microsomal fractions than females. Their relation of subcellular fraction weights tends more to the microsomal side. In liver homogenate and subcellular compartments, males contain significantly higher concentrations of beta-muricholic acid and other metabolites of chenodeoxycholic acid, females higher proportions of chenodeoxycholic acid. Higher concentrations of potentially toxic nonsulphated dihydroxy bile acids in the liver of female rats could be a sign of slower elimination, and the cause of higher susceptibility of females to liver injury induced by bile acid administration.

[Peritoneoscopy and liver biopsy in the diagnosis of liver disease (author's transl)]

In two prospective studies including 962 patients and one retrospective study including 165 patients the problem was investigated, to what extend ultrasonography might change the diagnostic value of clinical examination, peritoneoscopy, guided liver biopsy and blind liver biopsy. It turned out, that liver biopsy is the method of choice in diffuse-parenchymatous disease (e.g. chronic active hepatitis, chronic persistent hepatitis, fatty liver), whereas laparoscopy is to be preferred if focal lesions (e.g. liver carcinoma) are present. Diffuse liver disease was present in 80% of the cases investigated; in this group of patients the diagnostic value of blind biopsy is equivalent to the diagnostic value of guided biopsy. Thus, blind biopsy does yield satisfactory results in most patients if it is possible to differentiate between diffuse and focal disease by ultrasonography. Such differentiation could be achieved in 77-98% of our cases, thus ultrasonography could intake a decrease in numbers of peritoneoscopies and an increase of blind liver biopsy.

[The influence of chenodeoxycholic acid on the concentrations of nonsulfated bile acids in the small and large intestinal mucosa of rats (author's transl)]

In male Wistar rats nonsulfated bile acids of small and large intestinal wall and feces are analysed after 2, 5, 9 and 14 days of oral administration of 20 or 90 mg chenodeoxycholic acid (CDCA)/kg. Development of body, intestinal, and fecal weights is assessed. A transient reduction of daily body weight gain and small and large intestinal weights is compensated after 14 days. Fecal weights are above controls under 20 mg/kg, below controls under 90 mg/kg. Containing about 2 mg, i.e. nearly 4% of the bile acid pool, the intestinal wall holds four times more bile acids than the liver. Under CDCA administration bile acid concentrations in the small intestinal wall and feces rise, and remain almost unchanged in the colonic wall. Changes after CDCA administration suggest that bile acid absorption is accompanied by an increase in mucosal bile concentration. In the colonic wall the increase in bile acid concentration after CDCA administration correlates with the passive permeability coefficient.

[Morphologic investigations on the toxicity of orally applied CDCA in the liver, gastro intestinal tract, kidney and adrenal gland of the rat (author's transl)]

Light- and electron microscopic alterations of the liver and light microscopic findings in the gastro intestinal tract, the kidney and adrenal gland of 80 female Wistar-Rats under CDCA therapy are reported. CDCA was applied by means of an endopharnygeal tube over a period of 60 days in doses of 150, 250, 500 and 1000 mg/kg body weight. The organs were examined at different times. We compared the achieved findings to results obtained already beforehand by light- and electron microscopy after application of 20, 50 and 90 mg/kg body weight and day: Up to a dosage of 90 mg/kg morphological changes of the liver were only visible electron optically, from 150 mg/kg onward they could be seen light optically as well. After 60 days a cirrhosis-like picture had developed. The lethal dose was established at 1000 mg/kg. There were no pathological alterations in the gastrointestinal tract and no definite ones in the kidneys. The adrenal glands were unchanged.--Since there are in the rats, in spite of potent mechanisms of detoxication of CDCA and LCA, even at low doses morphological alterations to be seen, the existence of other toxic, at this moment still unknown metabolites is being discussed.