Die Karotisstenose: Diagnostik, Patientenselektion, Therapie

Atheromatöse Verengungen der Arteria carotis interna im Bereich der Bifurkation sind mit einem Hirnschlagrisiko verbunden, das 20–25% nach drei Jahren für hochgradige symptomatische Stenosen und 2–3% pro Jahr für hochgradige asymptomatische Stenosen beträgt. Die Diagnose einer Karotisstenose wird entweder nach einem zerebralen ischämischen Ereignis oder anlässlich einer Gefäßuntersuchung gestellt, wobei die Doppler/Duplex-Sonographie als Screening-Methode der Wahl eingesetzt wird. Die Ultrasonographie ermöglicht auch eine präzise Bestimmung des Stenosegrades und demzufolge des Hirnschlagrisikos. Die Bestätigung des sonographischen Befundes wird heutzutage mit Hilfe der MR- oder CT-Angiographie nicht-invasiv durchgeführt. Steht die Diagnose einer Karotisstenose fest, wird die Frage nach ihrer Behandlung individuell entschieden, wobei eine operative Behebung der Stenose zusätzlich zur besten medizinischen Therapie nur einen Sinn hat, wenn die Risiken des Eingriffes signifikant kleiner sind als die Risiken der medizinischen Therapie allein. Für die Einschätzung der perioperativen Risiken werden nur die Mortalität und die schwere neurologische Morbidität berücksichtigt. Die lokalen und systematischen Komplikationen sind vorübergehender Natur und beeinflussen das Endresultat der Intervention nicht. Eine hochgradige symptomatische Karotisstenose (70–99%) wird, wenn immer möglich, operativ behandelt. Eine mittelgradige symptomatische Stenose (50–69%) wird operiert, wenn sie mit einem hohen Hirnschlagrisiko verbunden ist. Eine hochgradige asymptomatische Stenose wird nur operiert, wenn die geschätzte perioperative Komplikationsrate weniger als 3% beträgt. Eine mittelgradige asymptomatische Stenose, sowie leichtgradige Stenosen werden nicht operiert, sondern nur medizinisch behandelt. Die Karotisendarterektomie gilt aktuell als Methode der Wahl für die operative Behandlung einer Karotisstenose, wobei eine Rate schwerer Komplikationen von weniger als 1% in erfahrenen Zentren erreicht wird. Der Vorteil der Operation hält sich über Jahre und die Restenoserate ist sehr tief. Als Alternative zur offenen Operation wird die endovaskuläre Therapie mit Angioplastie und Stenteinlage zunehmend angewandt. Aktuell fehlt noch die Evidenz für den primären Einsatz dieser Methode. Technische Fortschritte werden voraussichtlich die Sicherheit und Wirksamkeit der endovaskulären Therapie in der Zukunft entscheidend steigern.

Effects of cerebral perfusion pressure and increased fraction of inspired oxygen on brain tissue oxygen, lactate and glucose in patients with severe head injury

OBJECTIVE

The purpose of the study was to measure the effects of increased inspired oxygen on patients suffering severe head injury and consequent influences on the correlations between CPP and brain tissue oxygen (PtiO2) and the effects on brain microdialysate glucose and lactate.

METHODS

In a prospective, observational study 20 patients suffering severe head injury (GCS< or =8) were studied between January 2000 and December 2001. Each patient received an intraparenchymal ICP device and an oxygen sensor and, in 17 patients brain microdialysis was performed at the cortical-subcortical junction. A 6 h 100% oxygen challenge (F IO2 1.0) ( Period A) was performed as early as possible in the first 24 hours after injury and compared with a similar 6 hour period following the challenge ( Period B). Statistics were performed using the linear correlation analysis, one sample t-test, as well as the Lorentzian peak correlation analysis.

RESULTS

F IO2 was positively correlated with PtiO2 (p < 0.0001) over the whole study period. PtiO2 was significantly higher (p < 0.001) during Period A compared to Period B. CPP was positively correlated with PtiO2 (p < 0.001) during the whole study. PtiO2 peaked at a CPP value of 78 mmHg performing a Lorentzian peak correlation analysis of all patients over the whole study. During Period A the brain microdialysate lactate was significantly lower (p = 0.015) compared with Period B. However the brain microdialysate glucose remained unchanged.

CONCLUSION

PtiO2 is significantly positively correlated with F IO2, meaning that PtiO2 can be improved by the simple manipulation of increasing F IO2 and ABGAO2. PtiO2 is positively correlated with CPP, peaking at a CPP value of 78 mmHg. Brain microdialysate lactate can be lowered by increasing PtiO2 values, as observed during the oxygen challenge, whereas microdialysate glucose is unchanged during this procedure. Extension of the oxygen challenge time and measurement of the intermediate energy metabolite pyruvate may clarify the metabolic effects of the intervention. Prospective comparative studies, including analysis of outcome on a larger multicenter basis, are necessary to assess the long term clinical benefits of this procedure.

Diagnostic management of orthostatic intolerance in the workplace

OBJECTIVE

Orthostatic intolerance (OI) is a syndrome that is characterised by headache, concentration difficulties, palpitation of the heart, dizziness associated with postural tachycardia and plasma norepinephrine concentrations that are disproportionately high when the sufferer is in the upright posture. In contrast to other forms of orthostatic dysregulation - orthostatic hypotension (OH) and postural orthostatic tachycardia syndrome (POTS) - OI, hitherto, could be diagnosed only by a tilt table examination, with high expenditure. In this paper we examine the reliability and validity of a questionnaire as a screening instrument for OI.

METHODS

We studied 138 young men (mean age 21.6 years) who were undergoing military service. After a medical check and filling in the questionnaire, the participants underwent a tilt table test including monitoring of blood pressure, heart rate and plasma catecholamines, in the supine position and during 30 min of standing. The questionnaire consisted of ten items registering presence and frequency of typical OI symptoms.

RESULTS

Probands (104) showed normal tilt table test results. OI was diagnosed in 14 probands, OH in 6 and POTS in 14. The OI participants scored significantly higher in the questionnaire than the healthy subjects did: the mean score of the OI group was 22.6, the healthy participants had a mean score of 3.9. Participants with POTS had a mean score of 13.5 and subjects with OH had a mean score of 17.0. Reliability analysis showed a Cronbach's alpha of 0.888. Validity analysis showed that 93.5% of the probands with any kind of orthostatic dysregulation can be detected.

CONCLUSIONS

We were able to establish a short questionnaire as a reliable and valid screening instrument for OI. Usage of this questionnaire can simplify enormously the diagnostic management of patients with suspected OI.

Health consequences of an intravenous injection of metallic mercury

BACKGROUND

Mercury poisoning presents a variety of clinical pictures depending on chemical structure, the route of exposure, amount absorbed and individual factors. Thus, an injection of metallic mercury can be considered relatively harmless in contrast to inhalation of mercury vapor. Injection of elemental mercury is rare, and a total of only 78 cases have been reported in the literature over the period 1923-2000.

CASE REPORT

We report a suicide attempt by intravenous injection of approximately 8 g metallic mercury. By X-ray examination widespread multiple mercury shadows were visible in the whole lung and also in the subcutaneous region of the cubital fossa, the small pelvis and the right hypogastrium. Mercury excretion after treatment with 2,3-dimercaptopropane-1-sulfonate (DMPS) was significantly higher than in occupationally exposed workers.

CLINICAL SYMPTOMS

The patient showed symptoms typical of acute mercury intoxication, including gastroenteritis, ulceromembranous colitis and stomatitis mercuralis. No biochemical abnormalities in hepatic or renal function occurred, despite the persistence of metallic densities in the body. The patient's lung function was normal. The patient transitionally developed erethismus and tremor mercuralis. After 1 month of DMPS treatment, the mercury levels in blood were still high and the tremor was persistent. Three years after the suicide attempt the surgical removal of residual mercury in the left fossa cubitalis was performed. The extirpation of residual mercury was successful in cutting the mercury levels to almost half. After the operation the patient showed no symptoms of chronic mercury intoxication.

CONCLUSIONS

Since only 1 mg of mercury per day could be removed with DMPS treatment, it can be calculated, that it would take about 8,000 daily treatments to remove a total of 8 g solely by DMPS. Although DMPS itself does not dissolve the metallic deposits, it may considerably reduce the blood level of mercury and may therefore mitigate clinical symptoms, albeit transitorily. We therefore recommend that in cases of symptomatic metallic mercury injections, where the mercury cannot be removed by surgery, the patient's condition should be managed by repeated long-term DMPS treatment in order to control blood mercury levels.

Magnetic resonance angiography with ultrashort echo times reduces the artefact of aneurysm clips

We evaluated the ability of an ultrashort echo time (TE) three-dimensional (3D) time-of-flight (TOF) magnetic resonance angiography (MRA) sequence to reduce the metal artefact of intracranial aneurysm clips and to display adjacent cerebral arteries. In five patients (aged 8-72 years) treated with Elgiloy or Phynox aneurysm clips we prospectively performed a conventional (TE 6.0 ms) and a new ultrashort TE (TE 2.4 ms) 3D TOF MRA. We compared the diameter of the clip-induced susceptibility artefact and the detectability of flow in adjacent vessels. The mean artefact diameter was 22.3+/-6.4 mm (range 14-38 mm) with the ultrashort TE and 27.7+/-6.4 mm (range 19-45 mm) with the conventional MRA ( P<0.0001). This corresponded to a diameter reduction of 19.5+/-9.2%. More parts of adjacent vessels were detected, but with less intense flow signal. The aneurysm dome and neck remained within the area of signal loss and were therefore not displayed. Ultrashort TE MRA is a noninvasive and fast method for improving detection of vessels adjacent to clipped intracranial aneurysms, by reducing clip-induced susceptibility artefact. The method cannot, however, be used to show remnants of the aneurysm neck or sac as a result of imperfect clipping.

Estrogen sulfamates: a new approach to oral estrogen therapy

Sulfamate substitution (-O-SO2-NH2) at carbon atom 3 of the steroid skeleton leads to orally active prodrugs of estrogens with much higher systemic, but lower hepatic, estrogenic activity than their parent steroids. This dissociation is achieved by first passage through the liver in erythrocytes, followed by systemic hydrolysis which releases the 'parent' estrogen. In the rat, orally administered tritiated estradiol sulfamate, unlike estradiol, appears in the circulation at high concentrations. At Cmax, approximately one third of the administered dose forms a depot in the circulation (98% in erythrocytes, 2% in plasma). Significant estradiol, estrone and estrone sulfate concentrations were recorded in plasma during depletion of the red blood cell pool. Estradiol sulfamate (J995) has no estrogen receptor affinity per se or estrogenic activity in vitro ( i.e. without hydrolysis). Its oral uterotropic activity in rats is approximately 100 times greater than that of estradiol, however, its hepatotropic activity is only marginally elevated. These functions include bile secretion, the secretion of angiotensinogen, lipoproteins (total and high-density lipoprotein cholesterol) and insulin-like growth factor I (IGF-I). Orally administred estradiol sulfamate led to systemic estrogenic effects without significant hepatic responses, whereas estradiol and other 'conventional' estrogens exerted parallel systemic and hepatic estrogenic effects. Sulfamate technology represents an approach to the use of natural estrogens for fertility control and hormone replacement therapy in both genders. In this context, reduced effects on hemostatic factors, angiotensinogen, bile and IGF-I secretion seem the most important aspects. In addition, blood concentrations of estrogens are less variable than with conventional estrogens.

Neurobehavioral effects of vanadium

It was our aim to study whether chronic exposure to vanadium reduces cognitive abilities. We investigated effects on attention, visuospatial and visuomotor functioning, reaction time, short-term memory, and prefrontal functioning. Forty-nine vanadium exposed subjects with a mean vanadium level in urine (VanU) of 14.4 micro/L and 49 controls (VanU: 0.8 microg/L) with the same socioeconomic background were investigated. Neuropsychological tests were done using a modified Wisconsin Card Sorting Test (WCST), Block Design Test (BDT), Visual Recognition Test (VRT), Simple Reaction Time (SRT), Choice Reaction (CR), Digit Symbol Substitution (DSS), and Digit Span (DS). Exposure was assessed by using the vanadium level in urine and serum. While there were significant differences in BDT and DSS, no differences were found in WCST, SRT, CR, and DS. Significant correlations existed between the vanadium levels in urine and serum and the cognitive deficits. Vanadium concentrations around 14.2 microg/L in urine reduce neurobehavioral abilities, particularly visuospatial abilities and attention.

Follow-up of perfusion defects in pulmonary perfusion scanning after pulmonary embolism: are we too careless?

Persisting perfusion defects may still be found in pulmonary perfusion scintigraphy months or years after pulmonary embolism. The aim of this study was to investigate the rate of persisting perfusion defects and the pattern of scintigraphic follow-up of patients after pulmonary embolism. Only those patients were included into our study who received pulmonary perfusion scintigraphy between 1991 and 1999, and who had perfusion defects including at least one whole segment. These perfusion defects were considered as persisting perfusion defects if unchanged over at least 1 year. From 3640 patients examined, 451 (12.4%) had perfusion defects meeting the criteria of this study. Of those, 129 (28.6%) received a scintigraphic follow-up. In 62 patients (48.1%), a reperfusion of the defects was found. In 38 patients (29.5%), the defects persisted within a follow-up period of up to 12 weeks. However, no pulmonary perfusion scintigraphy was performed thereafter. Out of the 129 patients receiving a scintigraphic follow-up, only 29 (22.5%) had a follow-up over more than 1 year, 19 of those had persisting perfusion defects. It is concluded that our data show an inadequate scintigraphic follow-up of patients with pulmonary embolism which may lead to unnecessary anticoagulant treatment if persisting perfusion defects are misinterpreted as fresh pulmonary embolism. In many cases, there was no further follow-up even if reperfusion of the defects was lacking in early follow-up.

Antimicrobial resistance in respiratory pathogens isolated in Brazil during 1999-2000

The in vitro antimicrobial susceptibility of the respiratory pathogens Streptococcus Pneumoniae, Hemophilus influenzae, and Moraxella catarrhalis to commonly tested and prescribed agents was investigated during 1999-2000 and compared with results obtained during a previous 1997-1998 study. Of 448 isolates of S. Pneumoniae collected and tested in 1999-2000, 77.2% were susceptible, 19.9% were intermediate, and 2.9% were resistant to penicillin, demonstrating that there were no major changes in susceptibility to penicillin from 1997-1998 (77.1% susceptible, 18.7% intermediate, 4.2% resistant). All S. Pneumoniae isolates from 1999-2000 were susceptible to levofloxacin and vancomycin and >90% were susceptible to the B-lactams (amoxicillin-clavulanate, ceftriaxone, and cefuroxime) and macrolides (axithyromycin and clarithromycin), showing that susceptibility to these agents also remained unchanged since 1997-1998. The most notable increase in resistance between the two studies was demonstrated by trimethoprim-sulfamethoxazole, which increased from 23.4% to 38.6%. Penicillin resistance correlated with resistance to B-lactams, macrolides, and trimethoprim-sulfamethoxazole in both studies. In H. influenzae, the prevalence of B-lactamase-producing isolates remained unchanged (10.6% in 1999-2000; 11.0% in 1997-1998). All H. influenzae isolates were susceptible to levofloxacine, ceftriaxone, cefuroxime, and azithromycin, and showed no change between the two studies. Trimethoprim-sulfamethoxazole resistance was present in 40.1% of isolates in 1999-2000, and in 45.2% in 1997-1998. In M. catarrhalis, the prevalence of B-lactamase-producing isolates was unchanged (97.9% in 1999-2000;98.0% in 1997-1998). The most active agents against M. catarrhalis were azithromycin (MIC(90),< or = 0.03 microg/ml) and levofloxacin (MIC(90),< or = 0.03 microg/ml). Overall, these results suggest that, in Brazil, between 1999-2000 and 1997-1998, there have been no significant changes in the susceptibility of respiratory pathogens to any of the commonly tested and prescribed agents with the exception of trimethoprim-sulfamethoxazole for S. Pneumoniae.

[Development of a proverb test for assessment of concrete thinking problems in schizophrenic patients]

Concretism is considered an important aspect of schizophrenic thought disorder. Traditionally it is measured using the method of proverb interpretation, in which metaphoric proverbs are presented with the request that the subject tell its meaning. Interpretations are recorded and scored on concretistic tendencies. However, this method has two problems: its reliability is doubtful and it is rather complicated to perform. In this paper, a new version of a multiple choice proverb test is presented which can solve these problems in a reliable and economic manner. Using the new test, it is has been shown that schizophrenic patients have greater deficits in proverb interpretation than depressive patients.

Analysis of a putative voltage-gated prokaryotic potassium channel

Most of the completely sequenced prokaryotic genomes contain genes of potassium channel homologues, but there is still not much known about the role of these proteins in prokaryotes. Here we describe the large-scale overproduction and purification of a prokaryotic voltage-gated potassium channel homologue, Kch, from Escherichia coli. After successful overproduction of the protein, a specific increase in the potassium permeability of the cells was found. Kch could be purified in large amounts using classical purification methods to prevent aggregation of the protein. The physiological state of the protein was revealed to be a homotetramer and the protein was shown to be localized to the cytoplasmic membrane of the cells. In the course of the localization studies, we found a specific increase in the density of the cytoplasmic membrane on Kch production. This was linked to the observed increase in the protein to lipid ratio in the membranes. Another observed change in the membrane composition was an increase in the cardiolipin to phosphatidylglycerol ratio, which may indicate a specific cardiolipin requirement of Kch. On the basis of some of our results, we discuss a function for Kch in the maintenance of the membrane potential in E. coli.

Fertilizing characteristics of bovine sperm with flattened or indented acrosomes

Frozen semen from a control bull (C: 89% morphologically normal sperm) and two bulls with acrosomal defects (K1: 92% flattened acrosomes; K2: 82% indented acrosomes) were used to investigate the fertilizing ability of bull sperm with flattened or indented acrosomes. In experiment 1, frozen-thawed sperm were evaluated for acrosomal integrity with fluorescent microscopy. In experiment 2, proteolytic activity of the acrosomal contents of sperm was evaluated through a gelatin digestion assay. In experiment 3, an IVF test system was used to determine the ability of sperm with flattened or indented acrosomes to bind to bovine oocytes and penetrate the zona pellucida. In experiment 4, IVM zona-free bovine oocytes (ZFO) were fertilized and examined to evaluate sperm chromatin decondensation. In experiment 1, bulls K1 and K2 had a lower proportion of sperm with intact acrosomes (0 and 13.6 +/- 4.5%, respectively) than bull C (30.2 +/- 5.6%) after 2h of incubation. In experiment 2, the proportion of sperm with proteolytic activity, as indicated by gelatin digestion around sperm heads, did not differ among bulls (C: 55%, n=410; K1: 43%, n=426; K2: 48%, n=324). In experiment 3, a lower proportion of sperm with flattened (K1) or indented acrosomes (K2) bound to oocytes than sperm from the control bull, C. The percentage of zona penetrated (55%, n=20; 13%, n=23; 4%, n=25) and the mean (+/- S.E.M.) number of sperm penetrating these zona pellucida (19.7 +/- 2.5; 6.9 +/- 1.0; and 2.6 +/- 0.5) was higher (P<0.05) for bull C than for bulls K1 or K2, respectively. In experiment 4, the percentage of ZFO penetrated (95%, n=20; 52%, n=30; 30%, n=33) and the mean (+/- S.E.M.) number of sperm with chromatin decondensation (7.8 +/- 1.6; 0.8 +/- 0.2; and 0.3 +/- 0.1) were also higher (P<0.05) for the control bull, C than for bulls K1 or K2, respectively. Results suggest that although sperm with the flattened or indented acrosomes had a tendency to undergo spontaneous acrosome reaction on incubation after thawing, the proteolytic activity of the acrosomal contents appeared to be normal. Sperm with the flattened or indented acrosomes also appeared to have a reduced ability to fuse with oolemma as demonstrated by confocal microscopy. This would impair the ability to penetrate ooplasm and undergo sperm chromatin decondensation.

Pathogen frequency and resistance patterns in Brazilian hospitals: summary of results from three years of the SENTRY Antimicrobial Surveillance Program

BACKGROUND

Pathogen frequency and resistance patterns may vary significantly from country to country and also in different hospitals within a country. Thus, regional surveillance programs are essential to guide empirical therapy and infection control measures.

METHODS

Rank order of occurrence and antimicrobial susceptibility of pathogenic species causing bloodstream infections (BSI), lower respiratory tract infections (LRTI), wound or skin and soft tissue infections (WSSTI), and urinary tract infections (UTI) in hospitalized patients were determined by collecting consecutive isolates over a specified period of time, as part of the SENTRY Antimicrobial Resistance Surveillance Program (SENTRY). All isolates were tested by reference broth microdilution.

RESULTS AND CONCLUSIONS

A total of 3,728 bacterial strains were obtained from January, 1997, to December, 1999, from 12 Brazilian hospitals located in 4 states. The largest number of isolates were obtained from patients with BSI (2,008), followed by LRTI (822 cases), UTI (468 cases), and WSSTI (430 cases). Staphylococcus aureus was the most frequently isolated pathogen in general (22.8% - 852 isolates), followed by E. coli (13.8% - 516 cases) and Pseudomonas aeruginosa (13.3% - 496 cases). Staphylococcus aureus was also the most common species isolated from BSI (23.6%) and WSSTI (45.8%), and P. aeruginosa was the most frequent species isolated from patients with LRTI (29.4%). The main bacterial resistance problems found in this study were: imipenem resistance among P. aeruginosa (69.8% susceptibility) and Acinetobacter spp. (88.1% susceptibility); ESBL production among K. pneumoniae (48.4%) and E. coli (8.9%); resistance to third generation cephalosporins among Enterobacter spp. (68.1% susceptible to ceftazidime) and oxacillin resistance among S. aureus (34.0%) and coagulase negative staphylococci (80.1%). Only the carbapenems (88.1% to 89.3% susceptibility) showed reasonable activity against the Acinetobacter spp. isolates evaluated.

Long-term follow-up of an epidemiologically defined cohort of patients with Tourette syndrome

The goal of this study was to collect prospective longitudinal information on the development of an epidemiologically defined cohort of patients with Tourette syndrome. These data may improve prognostic understanding of the condition. This information will also be important for specification of an adult phenotype for genetic marker studies. A prospective longitudinal cohort study was conducted. Fifty-four of 73 patients from our 1986 prevalence study of Tourette syndrome in North Dakota school-aged children were eligible for inclusion. The subjects were diagnosed in 1984 and 1985. We were able to interview 39 of 54 eligible patients for 507 person-years of follow-up. For the cohort, tic severity declined by 59%, global assessment of functioning improved by 50%, and the average number of comorbidities decreased by 42%. Forty-four percent of patients were essentially symptom free at follow-up. Only 22% were on medication as adults. Tourette syndrome is a developmental neuropsychiatric disorder with a long-term course that is favorable for most patients. Males demonstrated substantially more variability in improvement but overall demonstrated more improvement than females.

Imaging tumors with peptide-based radioligands

Regulatory peptides are small, readily diffusable and potent natural substances with a wide spectrum of receptor-mediated actions in humans. High affinity receptors for these peptides are (over-) expressed in many neoplasms, and these receptors may represent, therefore, new molecular targets for cancer diagnosis and therapy. This review aims to give an overview of the peptide-based radiopharmaceuticals which are presently already commercially available or which are in advanced stages of their clinical testing so that their broader availability is anticipated soon. Physiologically, these peptides bind to and act through G protein-coupled receptors in the cell membrane. Historically, somatostatin analogs are the first class of receptor binding peptides having gained clinical application. 111In-DTPA-[D-Phe1]-octreotide is the first and only radiopeptide which has obtained regulatory approval in Europe and the United States to date. Extensive clinical studies involving several thousands of patients have shown that the major clinical application of somatostatin receptor scintigraphy is the detection and the staging of gastroenteropancreatic neuroendocrine tumors (carcinoids). In these tumors, octreotide scintigraphy is superior to any other staging method. However, its sensitivity and accuracy in other, more frequent neoplasms is limited. Radiolabeled vasoactive intestinal peptide (VIP) has been shown to visualize the majority of gastrointestinal adenocarcinomas, as well as some neuroendocrine tumors, including insulinomas (the latter being often missed by somatostatin receptor scintigraphy). Due to the outstanding diagnostic accuracy of the pentagastrin test in detecting the presence, persistence, or recurrence of medullary thyroid cancer (MTC), we postulated the expression of the corresponding (ie. cholecystokinin [CCK-] -B) receptor type in human MTC. This receptor is also widely expressed on human small-cell lung cancer. Indeed, 111In-labeled DTPA derivatives of gastrin showed excellent targeting of CCK-B receptor expressing tissues in animals and patients. A variety of further peptide-based radioligands, e.g. among many others, gastrin-releasing peptide/bombesin, neurotensin, substance-P, pan-somatostatin (somatostatin derivatives which bind to all five receptor subtypes) or glucagon-like peptide-1 (glp-1) analogs (the latter for the specific detection of insulinomas), is currently under development. Summarizing, radiolabeled regulatory peptides have opened new horizons in nuclear oncology for diagnosis (and potential internal radionuclide therapy). Future work will probably reveal a multitude of novel potentially clinically useful peptide-based radioligands.

The infrared absorption of amino acid side chains

Amino acid side chains play fundamental roles in stabilising protein structures and in catalysing enzymatic reactions. These fields are increasingly investigated by infrared spectroscopy at the molecular level. To help the interpretation of the spectra, a review of the infrared absorption of amino acid side chains in H(2)O and 2H(2)O is given. The spectral region of 2600-900cm(-1) is covered.

Clinical prevalence, antimicrobial susceptibility, and geographic resistance patterns of enterococci: results from the SENTRY Antimicrobial Surveillance Program, 1997-1999

As part of the SENTRY Antimicrobial Resistance Surveillance Program, a total of 4998 strains of enterococci isolated from 1997 to 1999 were processed. The occurrence of enterococcal infections by species and site of infection was analyzed, as were the occurrence of vancomycin-resistant enterococci (VRE) and their resistance phenotypes and genotypes. Trends in antimicrobial susceptibility to a variety of agents (including experimental compounds) were also reported. Enterococci accounted for >9% of isolates from all bloodstream infections (BSIs) in North America. Ampicillin was active against strains from Latin America and Europe but not against those from the United States and Canada. US isolates were considerably more resistant to vancomycin (17% resistant strains in 1999) than were those from patients in the rest of the world. The highest proportion of VRE was observed among BSI isolates (81.7%). Quinupristin-dalfopristin, chloramphenicol, and doxycycline were the most active agents tested against VRE. The results of this study confirm the worldwide trend in increasing occurrence of enterococci and the emerging pattern of antimicrobial resistance among such isolates.

[Chronic anemia and abdominal pain as a sequela of lead poisoning]

HISTORY AND ADMISSION FINDINGS

3 years ago, a 63-year-old man underwent laparotomia due to clinical signs of acute abdominal pain. The anemia was treated with erythrocyte concentrates. Several weeks before the current admission to our outpatient department, the patient was again hospitalized because of acute abdominal pain and anemia. The patient was then transferred to the University clinic for further medical tests.

INVESTIGATIONS

In addition to a normocytic anemia, a secondary porphyria was found. Further medical tests demonstrated lead poisoning.

DIAGNOSIS, TREATMENT AND COURSE

Initially, the cause of the lead poisoning remained unclear because the patient had reported neither an occuppational nor an environmental exposure to lead. Finally, a prescription-prepared ointment was evaluated, which the patient had applied to his feet and lips over the past 3 years.

CONCLUSION

Lead poisoning can be found outside the realm of occupational exposure; therefore, the knowledge of lead poisoning is still important.