Non-destructive detection of large molecules without mass limitation.

The problem for molecular identification knows many solutions, which include mass spectrometers whose mass sensitivity depends on the performance of the detector involved. The purpose of this article is to show by means of molecular dynamics simulations how a laser-cooled ion cloud, confined in a linear radio-frequency trap, can reach the ultimate sensitivity providing the detection of individual charged heavy molecular ions. In our simulations, we model the laser-cooled Ca+ ions as two-level atoms, confined thanks to a set of constant and time oscillating electrical fields. A singly charged molecular ion with a mass of 106 amu is propelled through the ion cloud. The induced change in the fluorescence rate of the latter is used as the detection signal. We show that this signal is due to a significant temperature variation triggered by the Coulomb repulsion and amplified by the radio-frequency heating induced by the trap itself. We identify the optimum initial energy for the molecular ion to be detected, and furthermore, we characterize the performance of the detector for a large range of confinement voltages.

[Human genetics in atypical hemolytic uremic syndrome-its role in diagnosis and treatment]. / Humangenetik beim atypischen hämolytisch-urämischen Syndrom ­ Rolle in Diagnostik und Therapie.

The atypical hemolytic uremic syndrome (aHUS), one of the three major forms of thrombotic microangiopathy, is characterized by genetic alterations in the area of the complement cascade, which can be detected in 40%-60% of all patients with aHUS. Mutations in over 10 different genes have now been identified. The most frequent and clinically relevant of these are mutations that result in a decreased or absent function of factor H, the formation of hybrid genes, or the formation of autoantibodies against factor H. Although genetics are not required for the diagnosis of aHUS, it is of great importance for the decision on how long to treat with the C5 inhibitor eculizumab. Also, knowledge of genetic alterations is absolutely essential if a living related donor is considered, in order to protect the living donor and recipient from developing aHUS.

Correcting symmetry imperfections in linear multipole traps.

Multipole radio-frequency (RF) traps are central to collisional experiments in cryogenic environments. They also offer possibilities to generate new type of ion crystals topologies and in particular the potential to create infinite 1D/2D structures: ion rings and ion tubes. However, multipole traps have also been shown to be very sensitive to geometrical misalignment of the trap rods, leading to additional local trapping minima. The present work proposes a method to correct non-ideal potentials, by modifying the applied RF amplitudes for each trap rod. This approach is discussed for the octupole trap, leading to the restitution of the ideal Mexican-Hat-like pseudo-potential, expected in multipole traps. The goodness of the compensation method is quantified in terms of the choice of the diagnosis area, the residual trapping potential variations, the required adaptation of the applied RF voltage amplitudes, and the impact on the trapped ion structures. Experimental implementation for macroscopic multipole traps is also discussed, in order to propose a diagnostic method with respect to the resolution and stability of the trap drive. Using the proposed compensation technique, we discuss the feasibility of generating a homogeneous ion ring crystal, which is a measure of quality for the obtained potential well.

Terahertz frequency standard based on three-photon coherent population trapping.

A scheme for a terahertz frequency standard based on three-photon coherent population trapping in stored ions is proposed. Assuming the propagation directions of the three lasers obey the phase matching condition, we show that stability of few 10(-14) at 1 s can be reached with a precision limited by power broadening to 10(-11) in the less favorable case. The referenced terahertz signal can be propagated over long distances, the useful information being carried by the relative frequency of the three optical photons.

Antibiotic prophylaxis in cerebrospinal fluid shunting: reassessment of Cefotiam penetration into human CSF.

OBJECTS: Shunt infection is a major complication of shunt implantation. Numerous clinical studies give evidence that antibiotic prophylaxis is efficacious in preventing infections after cerebrospinal fluid shunting. In CSF shunting, antibiotics need to reach sufficient concentrations not only in the blood shielding the operative field but also in tissues and the CSF compartment. Cefotiam is widely used for prophylaxis in neurosurgery. Some clinical trials report that this beta-lactam is able to penetrate considerably into the CSF. However, these studies include disease patterns which are most likely to be associated with a pathological permeability of the blood-brain barrier. Therefore, this study was designed to investigate the extent of penetration of Cefotiam into human CSF in patients without morphological disruption of the blood-brain barrier. METHODS: The penetration of Cefotiam into human CSF was investigated in 23 patients without morphological disruption of the blood-brain barrier undergoing CSF shunt surgery. 2 g Cefotiam was administered prior to surgery as a short-term infusion for a period of 15 min. Samples of blood and CSF were collected intraoperatively. The concentrations of Cefotiam were determined by bioassay. RESULTS: All patients (n=23) showed moderate to high plasma levels of Cefotiam (range: 19.8-146.2 mg/L); the pharmacokinetic profiles in blood accorded well with published data. In contrast to earlier studies, no Cefotiam was detected in CSF. CONCLUSION: This study clearly demonstrates that Cefotiam does not penetrate through an intact blood-brain barrier into human CSF. Although Cefotiam has been shown to be valuable for the perioperative prophylaxis of shunt infection, other antibiotics might be superior if they are capable of entering the CSF. Further studies are required to address this assumption.

[Rare pulmonary manifestation of an intracranial meningothelial meningioma]. / Seltene pulmonale Manifestation eines intrakraniellen meningothelialen Meningeoms.

HISTORY AND CLINICAL FINDINGS: A 53-year-old sailor was admitted to our department with the history of severe headache, dysphasia and mild psychotic behavior. Routine chest X-rays several weeks before had shown a focal lung lesion in the lower lobe of the right lung. The patient was without pulmonary symptoms. INVESTIGATIONS: Brain magnetic resonance imaging demonstrated a large intracranial extracerebral mass with perifocal brain edema in the right frontoparietal region. THERAPY: The patient was suspected of having a metastasis of an unknown primary tumor. Craniotomy and total removal of the tumor was performed. Histological examination revealed a meningothelial meningioma without signs of malignancy. 6 weeks later thoracotomy and total removal of the lung tumor were performed. Histological examination revealed a meningioma with the same histological pattern as the intracranial lesion. Postoperatively there were no complications, the physical examination at discharge was normal without any pulmonary or neurological deficits. Two years later, we found no evidence of an intracranial or pulmonary tumor recurrence. CONCLUSION: Pulmonary metastases of benign intracranial meningiomas are rare but should be considered in the differential diagnosis, especially in cases with an undiscovered primary tumor.

[Successful repair of complete pancreatic rupture and subtotal duodenal avulsion after blunt abdominal trauma in childhood--a case report]. / Erfolgreiche Organerhaltung nach kompletter Pankreasruptur und subtotalem Duodenalabriss durch stumpfes Bauchtrauma im Kindesalter: Ein Fallbericht.

We report the case of a 12-year-old boy who presented after a bicycle accident with handlebar injury of the epigastrium with clinical signs of hollow visceral injury and elevated pancreatic enzymes. Upon emergency laparotomy, a complete rupture of the pancreatic isthmus and a nearly total transsection of the postpyloric duodenum were encountered (Grade IV according to Lucas). Reconstruction consisted of reanastomosis of the proximal duodenum, closure of the distal end of the pancreatic head and internal drainage of the left pancreas into a Roux-en-Y jejunal loop. The postoperative course was uneventful. For rare traumatic pancreaticoduodenal lesions only individual surgical concepts are promising depending on the extent of damage. However, effort should be made to preserve as much pancreatic tissue as possible.

[Inflammatory alterations of the greater omentum--a difficult preoperative diagnosis]. / Entzündliche Erkrankungen des grossen Netzes--eine schwierige präoperative Differenzialdiagnose.

Isolated inflammatory alterations of the greater omentum are rare diseases. Since the preoperative diagnosis is difficult these changes are usually ascertained upon laparotomy. Between 1999 and 2001 four patients (44-88-years-old, 2 males) underwent laparotomy for an inflammatory tumor mass or an acute abdomen, respectively. C-reactive protein was elevated in all cases. In two cases a primary torsion of the greater omentum was found, in the other two a paracolic pseudotumorous omentitis. Resection of the diseased omental parts led to complete recovery. Torsion of the greater omentum and omentitis cause abdominal symptoms with an inflammatory component that often mimics other more common diseases such as acute appendicitis and urges laparotomy. Partial omentectomy is the therapy of choice.

[Acute hemorrhage from Meckel's diverticulum--Laparotomy or laparoscopy?]. / Die akute Blutung aus einem Meckel'schen Divertikel - Laparotomie oder Laparoskopie?

Meckel's diverticulum is the most common congenital malformation of the gastrointestinal tract with a potential risk to develop complications such as obstruction, diverticulitis or intussusception. Lower gastrointestinal bleeding due to ulceration of heterotopic gastric tissue of the diverticulum is a known phenomenon in children and young adults. We present two cases of a 15-year-old girl and a 20-year-old man that revealed a massive lower gastrointestinal hemorrhage of unknown origin. In this emergency situation laparotomy was performed in combination with lower endoscopy as rendezvous manouver. In both cases a Meckel's diverticulum with peptic ulceration was the source of hemorrhage, in one case the bleeding was active and visible. After resection of a short small bowel segment and end-to-end anastomosis the postoperative course was uneventful. We prefer in the case of lower gastrointestinal hemorrhage with hemodynamic instability laparotomy with intraoperative endoscopy instead of laparoscopy.

[Surgical therapy of giant tubulovillous adenoma of the duodenum and incidental serous cystadenoma of the head of the pancreas]. / Chirurgische Therapie bei tubulovillösem Riesenadenom des Duodenums und inzidentellem serösem Zystadenom des Pankreaskopfes.

A villous giant adenoma of the duodenum was diagnosed in a 56-year-old female patient with uncharacteristic upper abdominal discomfort after multiple previous laparotomies for various indications. A partial pancreaticoduodenectomy was performed as radical oncological procedure since the dignity of the neoplasm was uncertain. Histopathologic examination revealed medium-grade cell dysplasia of the villous adenoma but an incidental serous cystadenoma of the pancreatic head as well. The postoperative course was uneventful. The coincidence of these both rare neoplastic entities has yet not been described in the literature. The surgical options for treatment of both neoplasms are discussed.

Effect of caseload on the short-term outcome of colon surgery: results of a multicenter study.

This prospective multicenter study investigated the effect of hospital caseload on early postoperative outcome of surgery for carcinoma of the colon in 75 German hospitals and included 2293 patients. The hospitals were divided into those with a caseload of 1-30 (group A), 31-60 (group B), and more than 60 (group C) operations. Increasing caseload was associated only with fewer general postoperative complications. It was also associated with significantly greater use of antibiotic prophylaxis. No significant differences between the groups were found in resection rates, intraoperative complications, specific postoperative complications, overall postoperative morbidity, hospital mortality, or 30-day mortality. The significance of hospital caseload for the short-term postoperative outcome following surgery on the colon should not be overestimated. Basing conclusions about the results to be expected simply on the case volume is impermissible. On the basis of the available data it is not possible to establish a threshold value, that is, a minimum number of required operations.

Surgical management of gastrointestinal stromal tumors of the stomach.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are rare tumors of the GI tract with varying degree of dignity and prognosis. Intramural or extragastral growth of gastric GISTs is associated with diagnostic difficulties and uncertainty about the type and extent of surgical therapy. Based on our experience, we tried to formulate management guidelines for gastric GISTs. METHODS: Five patients with gastric GIST (36-85 years old) underwent subserosal excision with subsequent B-II resection (1x), full-thickness partial gastric resection (2x), gastrotomy with submucosal excision (1x), or gastrectomy for carcinoma with an incidental finding of a leiomyoma (1x). RESULTS: Tumor size ranged from 2x2x1 cm to 9x6x4 cm. These tumors were classified as epithelioid leiomyosarcoma (1x), GIST (3x), or leiomyoma (1x). The prognosis of risk ranged from no risk (leiomyoma) to low-malignancy (leiomyosarcoma) depending on tumor size and mitotic index. No recurrent disease has been noted so far during follow-up ranging from 3 months to 6 years. CONCLUSIONS: Staging of gastric disease should include the probability of gastric GIST. Surgical resection is the therapy of choice for potential malignant GISTs to ensure a local radical removal. Metachronic metastases should be resected if possible. Depending on tumor stage and prognostic parameters, an individual follow-up with endoscopic and radiologic examinations is recommended. Further studies should be undertaken to elaborate prognostic determinants and stage-adapted treatment.

[Diagnosis and management of an intraoperative vertebral artery injury]. / Diagnose und Notfallmanagement einer intraoperativen Verletzung der Arteria vertebralis.

A patient with cervical myelopathy caused by marked degenerative alterations of the cervical spinal column at the level of cervical vertebrae 3/4 and relative spinal canal stenosis in the area of cervical vertebrae 5-7 was treated in the department of neurosurgery because of progressive myatrophy and paresis of muscles innervated from cervical nerves 5-7. The operation was performed with vertebrectomy of cervical vertebra 6, implantation of a Harms titanium cage with autograft and a plate and spongy bone screw fixation system. There exists an unusual--and not often publicized--complication during this surgical procedure in the area of the cervical spine, namely penetrating injury of the vertebral artery caused by the treatment with a plate and spongy bone screw fixation system. We describe such an injury of the left vertebral artery. The vertebral artery was intraoperatively embolized using mechanical embolization coils.

[Bilobar liver hematoma and spontaneous rupture after cesarean section]. / Bilobäres Leberhämatom und Spontanruptur nach Sectio caesarea.

A 25-year-old woman delivered a healthy baby in the 34th week of gestation by caesarean section due to placental abruption and fetal bradycardia. On the following day she developed dyspnea, tachycardia, hypotension and rising serum transaminase levels. After exclusion of a pulmonary embolism, the abdominal CT scan and cavography revealed a subcapsular hematoma of the entire dorsal liver surface and compression of the retrohepatic vena cava. During laparotomy a spontaneous rupture of the liver capsule with intraperitoneal hemorrhage was found. The dorsal liver was decapsulated and the subcapsular hematoma completely removed. The postoperative course was uneventful.

[Partial hepatectomy after post-traumatic liver abscess]. / Leberteilresektion nach posttraumatischem Leberabscess.

Post-traumatic pyogenic liver abscess is a rare disease. We present the case of a 38-year-old man with multilocular liver abscess and pleural empyema following blunt abdominal trauma. The patient had a prodrome lasting 3 months before presenting in our department. The therapy included partial hepatectomy and pleural drainage. Clinical signs, diagnosis and possible therapy are discussed in this case report.

Effective therapy for hepatic M. Osler with systemic hypercirculation by ligation of the hepatic artery and subsequent liver transplantation.

Hereditary hemorrhagic teleangiectasia, or M. Osler (Osler-Weber-Rendu disease), is an autosomal dominant, systemic fibrovascular dysplasia. This may lead to increased liver blood flow from arteriovenous fistulas. A 45-year-old woman with a known M. Osler was admitted for liver transplantation. On admission, exertional dyspnea was the predominant symptom. Radiological investigations revealed multiple intrahepatic arteriovenous fistulas and consecutive high-output heart failure. Laboratory findings revealed remarkably elevated bilirubin and alkaline phosphatase. To alleviate the high-output cardiac failure, the hepatic artery was ligated. Fourteen months later, the patient presented again with increased levels of bilirubin and recurrent bleeding episodes from esophageal varices grade IV. The patient underwent liver transplantation and post-transplant recovery was excellent. A hyperdynamic circulatory state due to a hepatic M. Osler has been treated in several cases by ligation or embolization of the hepatic artery. This procedure, however, is recommended only for patients with normal liver function and carries a considerably risk of bile duct necrosis.

A randomized, placebo-controlled trial with anti-interleukin-2 receptor antibody for immunosuppressive induction therapy after liver transplantation.

The introduction of quadruple induction therapy after liver transplantation with the murine anti-interleukin-2 receptor (IL-2R) antibody (BT563) has decreased the incidence of serious side effects, such as tachycardia, hypertension, rash, fever and nausea since it does not lyse its target cell. To investigate the immunosuppressive efficacy of BT563, a placebo-controlled trial was performed and BT563 was added to the standard triple induction after liver transplantation. Forty consecutive recipients of primary orthotopic liver transplants (OLT) (median age 47 yr [range 18-65]) were randomized. All patients received triple immunosuppression with cyclosporine A (CyA), prednisolone (PRED) and azathioprine (AZA). In addition, 19 patients received BT563 (Biotest, Dreieich, Germany) at a dose of 10 mg/d from day 0 until day 12. The remaining 21 patients received a placebo infusion at the same days after transplantation. Minimal follow-up for all patients was 3 yr. Patient survival at 3 yr was 74% in the BT563 group and 90% in placebo group. Similar results were observed for graft survival. Two acute rejection episodes were detected in the BT563 group and 9 acute rejections (5 steroid-resistant) were observed in the placebo group (p < 0.034). The incidences of sepsis, pneumonia, cholangitis, urinary tract infections as well as cytomegalo-virus (CMV) infections were similar in both groups. Side effects of the BT563 therapy and/or post-transplant lymphoproliferative disease (PTLD) were not detected. Quadruple induction therapy with BT563 significantly reduces the incidence of rejection episodes after liver transplantation, while infectious complications and/or PTLD is not increased. Therefore, the anti-IL2 receptor antibody BT563 constitutes a safe and efficient addition to the immunosuppressive induction regimen following OLT.

Combined liver-kidney transplantation: long-term follow up in 18 patients.

Since August 1992, 18 patients underwent combined liver and kidney transplantation. Eight patients had lymphocytotoxic antibodies pretransplant and 5 of these patients (27.7%) had a positive crossmatch. Fifteen patients received cyclosporine-based immunosuppression and 3 patients were treated with a tacrolimus-based immunosuppressive protocol. One patient died in the postoperative course due to intractable bleeding episodes after 96 days and one kidney graft was lost due to technical complications. The 1 year survival rate of patients with combined transplantation was 95% vs 87% in patients with liver transplantation alone. None of the patients with a positive crossmatch experienced a hyperacute rejection of the kidney. The long-term patient and graft survival was not impaired in patients with a positive crossmatch. These results suggest that combined liver-kidney transplantation is a safe treatment for end-stage liver and renal disease. A positive crossmatch or positive lymphocytotoxic antibodies are not contraindications for a combined transplantation.