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Zusammenfassung: Um die ausgezeichnete Steinfreiheit der klassischen PCNL mit der geringeren Morbidität der miniaturisierten PCNL („Mini-Perc“) zu kombinieren und ein Höchstmaß an Effektivität und Patientenkomfort zu erreichen, wurde die minimal-invasive PCNL (MIP) entwickelt. Neben dem mit 18 French von der Mini-PNL übernommenen Schaftdurchmesser definiert sich dieses Verfahren noch über folgende weitere Merkmale: ultraschallgesteuerte Punktion, Einschrittbougierung des Zugangstraktes, Niederdruckspülung, Verwendung einer ballistischen Lithotripsie und der Fragmentbergung mittels „Staubsaugereffekt“ im Niederdruckspülstrom, sowie den direkten Traktverschluss mit Gelatine-Thrombin-Matrix unabhängig von Blutungen oder kleineren Restkonkrementen nach antegrader Harnleiterschienung. Die Ergebnisse der ersten 57 Patienten zeigen in 92,9% aller Fälle eine primäre Steinfreiheit bei einer Operationszeit von 62 (25–123) min. Schwere Komplikationen wie Sepsis oder transfusionspflichtige Blutungen wurden nicht beobachtet. Die hohe mit der MIP assoziierte, sofortige und damit planbare Steinfreiheit macht zusammen mit der geringen (mit URS und ESWL vergleichbaren) Morbidität dieses Verfahren für Patient und Arzt attraktiv. Der „Staubsaugereffekt“ mit der raschen Fragment- und Staubentfernung beschleunigt das Verfahren und beugt erneuter Steinbildung durch Fehlen von Nuklei vor. Der direkte, primäre Traktverschluss erhöht den Patientenkomfort und ist durch die in <8% aller Fälle notwendige und effektiv durchführbare sekundäre Restkonkremententfernung mittels flexibler URS gerechtfertigt. Die fehlende Notwendigkeit einer Second-look-Nephroskopie, der „Staubsaugereffekt“ und der verbesserte Patientenkomfort ohne Nephrostomie, sowie die mit der herkömmlichen PCNL vergleichbaren Operationszeiten stellen eine konsequente Weiterentwicklung der „Mini-PCNL“ dar. Damit präsentiert sich die MIP als viel versprechender und zukunftsweisender Baustein einer modernen Steintherapie.

Zusammenfassung: Fast alle Patienten mit hormonrefraktärem Prostatakarzinom (HRPCA) unter Androgenentzugstherapie entwickeln einen Tumorprogress, der sich anfangs meist durch einen Anstieg des prostataspezifischen Antigens (PSA) zeigt. In neueren Studien konnte zwar ein signifikanter Überlebensvorteil für Patienten mit fortgeschrittenem Prostatakarzinom (PCA) unter Taxan-basierter Chemotherapie gezeigt werden, jedoch haben die toxischen Nebenwirkungen einen starken negativen Einfluss auf die Lebensqualität. Im Stadium der Hormonunabhängigkeit kann der Progress noch durch sekundäre Manipulation des Androgenrezeptors oder anderer Rezeptoren und ihrer Signalwege verzögert werden. Zur sekundären Hormonmanipulation gehörten traditionell der Antiandrogenentzug, Wechsel des Antiandrogens und die Hemmung der adrenalen Testosteronproduktion, Östrogene oder Progestin. In dem Artikel soll die Wirkungsweise und Anwendung der Somatostatin-Analoga als neuartige Option der sekundären Hormonmanipulation bei Patienten mit fortgeschrittenem PCA auf Grundlage der aktuellen Literatur diskutiert werden.

Zusammenfassung: Die untere Kelchgruppe nimmt aufgrund ihrer besonderen anatomischen Lage unterhalb des Ureterabgangs eine Sonderrolle bei der Behandlung der Nephrolithiasis ein. Die extrakorporale Stoßwellenlithotripsie (ESWL) erzielt, selbst nach optimaler Desintegration von unteren Kelchsteinen, häufig nur unbefriedigende Abgangsraten und macht damit sekundäre Therapieverfahren notwendig. Aufgrund der guten primären Steinfreiheitsraten nimmt die komplikationsarme retrograde Steinentfernung seit der Entwicklung der modernen flexiblen Ureterorenoskope (URS) eine wichtige Rolle bei der Behandlung der unteren Kelchsteine ein. Die langen Behandlungszeiten bei großen Steinmassen und die beträchtlichen Materialkosten stellen limitierende Faktoren dar. Im Rahmen der Weiterentwicklung der perkutanen Nephrolitholapaxie (PCNL) steht heute mit der minimal-invasiven PCNL (MIP) eine vielversprechende Methode auch zur Behandlung großer unterer Kelchsteine zur Verfügung.

Extracorporeal shock wave lithotripsy (ESWL) is effective in the treatment of symptomatic cholecystolithiasis in well-selected patients. We analyzed the predictors of cholecystectomy in a large series of gallstone patients after ESWL. This was a retrospective follow-up cohort-study of consecutive patients undergoing ESWL for symptomatic cholecystolithiasis over a 9-year period. It was possible to analyze a total of 297 patients; there were 211 women and 86 men, with a mean age of 52 years (range, 8–81 years). Patients that had been cholecystectomized after ESWL were compared to patients with their gallbladder still in situ and determinants of cholecystemctomy in terms of clinical, stone, and gallbladder parameters and symptoms analyzed. The mean duration of follow-up was 99 months (range, 27–134 months). During follow-up, 106 (36%) patients underwent a cholecystectomy at a mean of 34 months (range, 0–127 months) after ESWL. Histological data showed a normal gallbladder wall in only 4 cases; 101 examinations revealed some kind of (chronic) inflammation, which was not different from histological gallbladder results in patients without prior lithotripsy. Three gallbladder polyps were found, but no carcinoma. Cholecystectomy after ESWL of gallbladder stones was strongly associated with persitent and/or renewed biliary symtoms. Nevertheless, only three of four patients became asymptomatic after CE. Thus, ESWL proved to be a valuable organ-preserving alternative to cholecystectomy in selected patients.

We investigated in a large industrial population the antibody response to specific H. pyloriantigens (CagA and seven others) in relation to peptic ulcer and nonulcer dyspepsia (NUD). The two groups consisted of 37 and 39 employees, respectively, with endoscopically proven peptic ulcer and NUD. Age- and gender-matched controls were H. pyloriseropositive employees without abdominal complaints or history of ulcer disease. IgG antibodies against CagA and other antigens were analyzed by western immunoblot. Relative percentages of CagA-positive individuals were 89 and 76% for ulcer cases and their controls (P= 0.22) and 77% and 74% for NUD cases and their controls. The corresponding percentages of VacA-positive individuals were 87 and 76% for ulcer cases and controls and 64% and 77% for NUD cases and controls, respectively. Analysis of other H. pylori-specific antigens was not particularly helpful in discriminating between symptomatic and asymptomatic seropositive individuals for either disease group. In conclusion, assessment of IgG response against specific H. pyloriantigens was not predictive of peptic ulcer or NUD case status in this active employee population and would not appear to be useful in routine clinical practice.

The differential diagnosis of bile duct stenosis requires different diagnostic tools: percutaneous ultrasound as noninvasive method and endoscopic ultrasound as a semiinvasive diagnostic tool. Endoscopic retrograde cholangiopancreatography or ± in patients with biliary diseases inappropriate for a transpapillary access ± percutaneous transhepatic cholangiography (PTC) are the ‘gold standard’ for evaluation of the site and the extent of the biliary stenoses. The continued use of diagnostic strategies such as intraductal ultrasound of the biliary duct system, cholangioscopy, and brush cytology help clarify the dignity of stenoses. A new noninvasive diagnostic approach to the suspected bile duct obstruction is the magnetic resonance cholangiopancreatography (MRCP). The endoscopic management of postoperative bile duct strictures by implantation of biliary endoprostheses leads in 74±90% to a successful long-term follow-up without surgical repair. The cycle of stent removal, dilatation, and re-stenting (usually with a larger or with more than one stent) must go on for up to 1 year with 3-month intervals before a stable situation is achieved and the stent can be discontinued. In conclusion the endoscopic management of common bile duct injuries should be the treatment of first choice.

An all digital phase-locked loop (DPLL) is designed, analyzed, and tested. Three specific configurations are considered, generating first, second, and third order DPLL's; and it is found, using a computer simulation of a noise spike, and verified experimentally, that of these configurations the second-order system is optimum from the standpoint of threshold extension. This substantiates results obtained for analog PLL's.

The gueast editors attempt to make the arguments: 1) that whereas there are many similarities between military and civil systems, there are also many differences; 2) that thes ources of the differences are iargely summed up with the terms survivability and interoperability; and 3) that broad systems approaches are necessary to achieve the desired goals. The systems approach is rarely described in technical journals. Because of this, the papers invited for this Special Issue feature systems approaches and overviews designed to give the reader some perspective as to what the main issues are in military communications. There is also a sprinkling of techniques-oriented papers, some invited and some submitted, to complete the picture. In keeping with this systems orientation, the Special Issue is divided,i nto four major sections, oriented to the principal categories into which the Defense Department divides its systems for management purposes. The first section contains two papers, both providing architectural overviews over system evolution. The second section is devoted to the category of Long-Haul Communications, with papers addressing various aspects of this category: systems, subsystems, and technology. The third section contains ten papers devoted to Tactical Communications, the name given to the category supporting command and control from the major field comnianders down to the lower echelons of command. The final section containing eight papers treats a variety of technical topics which are neither specifically long-haul nor tactical, but which, although primarily techniques-oriented, address specific military issues.

Measurements of the temperature dependent microwave dielectric permittivity of PVDF and 60%–40% VDF-TrFE copolymer are presented. A cavity perturbation method is used. At room temperature a surprisingly high absorption of microwave power is observed, which decreases with decreasing temperature. This behavior seems to be connected with the ferroelectric-to-para-electric phase transition. With the copolymers a dependence of the complex permittivity on annealing temperature is found. A model considering paraelectric fluctuations is proposed.

Polarized regions in Polyvinylidenefluoride (PVDF) have been imaged in scanning electron-microscopy by means of potential contrast at 2 keV. The contrast is observed to be dependent on temperature changes of the sample as well as on the angle of electron incidence. This method of imaging small polarized domains could be important for the application of PVDF as a ferroelectric memory.

Inhibitors of key components of intracellular signaling pathways were used to detect differences in the regulation of the production of interleukin 1β (IL-1β) and tumor necrosis factor α (TNFα) in macrophages activated with lipopolysaccharide (LPS). The protein kinase inhibitor staurosporine caused an increase in the level of IL-1β in supernatants of macrophages stimulated with LPS. Calphostin C and 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7) dihydrochloride, specific inhibitors of protein kinase C (PKC), also promoted enhancement of IL-1β secretion, but the effect was not as pronounced as that of staurosporine. In contrast, all three substances inhibited TNFα production. Measurement of IL-1β in lysates and supernatants of macrophage cultures indicated that staurosporine effected enhancement of the production of the cytokine in the cellular fraction, the greater portion of which was not secreted. Kinetics of accumulation of IL-1β mRNA and production of the cytokine during a 24 h period showed that enhanced production of IL-1β obtained 24 h after LPS stimulation of macrophages in the presence of staurosporine paralleled the increased levels in mRNA specific for the cytokine.

Very thin VDF-TrFE copolymer films were prepared by spin coating ranging in thickness down to 100 nm. Their dielectric and ferroelectric behaviour was measured as a function of thickness. Furthermore their surface roughness and their local piezoelectric properties were analysed by using a scanning tunneling microscope.

Little is known about how vocal patterns develop in non-human primates, mainly because suitable controlled experiments are difficult to carry out on these animals1. Results of isolation experiments2–4and observations of interspecific hybrids1,5suggest no greater role for vocal learning than exists in many other vertebrates6–9, and less than has been found in birds10–13. We have now studied vocal patterns of hybrids between white-handed gibbons (Hylobates lar) and pileated gibbons (Hylobates pileatus) in natural mixed-species groups, in a zone of interspecies contact in central Thailand, and in some captive mixed-species groups. We find that in female hybrids, the patterns of the loud and stereotyped ‘great-calls’ show no evidence of learning from parents, and appear to be under strong genetic control. Daughters maturing in groups with genetically unlike parents develop great-calls unlike those of their mothers, even though these calls develop only while the daughters sing simultaneously with their mothers.

Several letters to the editor are presented in response to articles in previous issues including "Tattoo data still on file," "Army announces big changes to the tattoo policy" and "Is the new retirement plan really better for career troops?"