Substituent Pattern Effects on the Redox Potentials of Quinone-Based Active Materials for Aqueous Redox Flow Batteries.

Quinone-based, aqueous redox flow batteries are a promising technology for large-scale, low-cost energy storage. To understand the influence of substituent and substituent pattern effects of quinone-based derivatives on the redox potential, a screening study was performed that included benzoquinone, naphtaquinone, and anthraquinone derivatives. The order of substituent influence is -OH>-Me/-OMe for decreasing the redox potential and -F<-SO3 - <-CN, -NO2 for increasing the redox potential, which is in agreement with general expectations. We found that the consideration of resonance and inductive effects design strategies of redox-active materials can be extended by the ability of intramolecular hydrogen bond formation, steric hindrance, and energetic differences of conformers for oxidized and reduced species. Due to the complexity and overlap of these effects, theoretical screening studies can provide guidance for the design of new molecular materials. In addition to the redox potential, other parameters such as stability, solubility, and kinetic rate constant or synthetic accessibility are crucial to consider.

[Malignant Sertoli cell tumors of the testes]. / Maligner Sertoli-Zell-Tumor des Hodens.

Sertoli cell tumors are a rare malignancy which account for approximately 1.5 % of all testicular tumors. Although malignant Sertoli cell tumors are uncommon, they are associated with a poor prognosis. So far 36 cases of malignant courses of disease have been described. We present a patient with a lymphogenic metastasized Sertoli cell tumor, who 24 months after orchiectomy and extended retroperitoneal lymphadenectomy is relapse-free.

Protein C and procollagen III peptide levels in patients with hepatic dysfunction after allogeneic hematopoietic stem cell transplantation.

Veno-occlusive disease (VOD) is one of the most serious complications following hematopoietic stem cell transplantation (HSCT) and is associated with a high mortality. We conducted a large trial on the clinical significance of protein C (PC) and procollagen III peptide (PNPIII) levels, which have been described as possible diagnostic markers of VOD. In total, 350 patients undergoing allogeneic HSCT were included. PC and PNPIII levels were analyzed prior to conditioning and weekly until 8 weeks after the HSCT. Signs of VOD and other transplantation-related complications (graft-versus-host disease (GVHD), toxicity, microangiopathic hemolytic anemia, infection) were recorded weekly throughout the trial. Patients showed a significant drop of the PC levels in VOD (70.3 vs 96.3%, P<0.001) and with increasing severity of aGVHD. Steroids increased the PC levels (69.4% vs 109.4%, P<0.001). The highest PNPIII levels were registered in patients with VOD (mean 6.3 IU/ml). Patients with aGVHD showed an elevation of PNPIII, especially patients with hepatic aGVHD. PC levels during conditioning do not predict VOD (98.5 vs 76.5%, NS). Although PC and PNPIII may play a role in the pathogenesis of VOD they cannot discriminate between complications with jaundice and are only of limited help in the differential diagnosis of VOD.

A multicomponent method for Fusarium toxins in cereal based food and feed samples using HPLC-MS/MS.

A reliable, sensitive and selective multicomponent method has been developed to determine 12 differentFusarium mycotoxins (trichothecenes type A and B, zearalenone) simultaneously in cereal and grain samples using liquid chromatography tandem mass spectrometry (LC-ESI-MS/MS). The sample preparation based on a standard extraction step followed by two different kinds of solid phase clean-up (multifunctional MycoSep(®) material) for trichothecenes, and an immuno-affinity purification which combined antibodies for aflatoxins, ochratoxin A and zearalenone (AOZ-IAC). For quantification of zearalenone (ZON) an internal standard (zearalanone, ZAN) was used, whereas for trichothecenes a recovery standard (verrucarol, VOL) was applied. The average recoveries for the trichothecenes ranged from 65% for nivalenol (NIV) up to 96% for deoxynivalenol (DON) and 89% for zearalenone. The limit of quantification is different for each of the individual trichothecenes and in the range of 1 ppb to 10 ppb.

Flow cytometric findings in platelets of patients following allogeneic hematopoietic stem cell transplantation.

Following allogeneic hematopoietic stem cell transplantation (HSCT) patients may have an increased bleeding tendency in spite of a normal platelet count. Moreover, an association between chronic graft-versus-host disease (cGVHD) and a thrombophilic state has been observed. Platelet receptors and granules from 27 patients following HSCT (13 without cGVHD, 14 with cGVHD) were evaluated by flow cytometric analysis and compared to 62 healthy controls. Platelets from HSCT patients stained weakly with mepacrine indicating a reduced content of dense bodies, whereas no significant degranulation reaction of alpha granules and lysosomes was detectable. In addition, a lower surface expression of GP Ia/IIa was observed, indicating an acquired thrombocytopathy. The surface receptors are activated in HSCT patients, which could be seen by the lower surface expression of GP Ib internalized during the activation process and elevated levels of LIBS-1 and PAC-1 antibody binding. Patients with cGVHD had a seven-fold increased ratio of microparticles. This study demonstrates platelet receptor and granule defects in patients following HSCT. The key role of platelets in HSCT-associated hemostatic disorders is underscored by the high levels of circulating microparticles in cGvHD patients which might explain the thrombophilic state in these patients.

The pH response of rat cutaneous nociceptors correlates with extracellular [Na+] and is increased under amiloride.

Excess hydrogen ions induce sustained nociceptor excitation as well as pain, and this has been suggested, with evidence from sensory ganglion cells, to result from gating a slowly inactivating sodium/calcium inward current. In the rat skin-nerve preparation, isolated receptive fields of pH-sensitive C-fibre terminals were exposed to low-pH solutions of various sodium concentrations. The pH responses showed a good correlation with log [Na+]e, which supports the above model. Amiloride has previously been shown to block a pH-induced Na+ current involved in sensory transduction in hamster taste cells; however, it has been shown to act differently in cutaneous nociceptors. Amiloride induced a dose-dependent increase in and prolongation of the nociceptive pH responses, with a prominent acceleration of the onset. The latter could be mimicked by replacing external sodium with sucrose, thus impeding sodium-proton antiport. Together, the findings indicate functional expression of amiloride-sensitive Na+/H+-antiporters, which enable the nociceptive nerve endings to extrude invading H+. Intracellular acidification may thus compete with Na+/H+ exchange, and pHi may be decisive in the transduction of nociception and pain from tissue acidosis.

Unilateral linear lichen planus with mucous membrane involvement.

Linear lichen planus is a rare distinctive variant of lichen planus (LP) characterized by a pruritic eruption of lichenoid, violaceous papules in a linear distribution that sometimes assume a Blaschko line pattern. We describe a 33-year-old woman who presented with a 4-month history of a slightly pruritic unilateral linear array of papular lesions on the left side of her neck that were clinically and histologically consistent with linear LP. Two months after the onset of her skin disease she developed typical lesions with a lacy white pattern on the left lateral aspect of her tongue and the left buccal mucosa with a striking predominance for the left side. Clinically the lesions on the patient's neck were similar to lichen striatus or lichenoid epidermal naevus, a variant of linear verrucous epidermal naevus. However, the histological features and the fact that later in the course of her disease the patient developed typical LP of the oral mucosa suggest that this patient has the rare condition of linear LP with unilateral restriction.

Imaging modalities in Peyronie's disease. An intrapersonal comparison of ultrasound sonography, X-ray in mammography technique, computerized tomography, and nuclear magnetic resonance in 20 patients.

OBJECTIVE: Peyronie's disease is an ill-understood condition afflicting men in their 40s with the reported age ranging from 18 to 68 years. It is characterized by a plaque in the tunica albuginea which leads to penile deformity making sexual intercourse difficult if not impossible and is often accompanied by severe pain upon erection in the early stage; erectile dysfunction is present in about 2% of cases. Diagnosis rests upon medical history, clinical examination with plaque palpation and autophotography in two planes. These diagnostic steps are not plaque-specific and therefore we wanted to assess which imaging modalities would allow for an objective determination of the plaque status. MATERIALS AND METHODS: We evaluated 20 patients with Peyronie's disease. All patients underwent clinical examination including autophotography and the subsequent use of the following imaging techniques: (1) ultrasound (US) using a 7.5-MHz transducer with a profile for semiquantitative density analysis; (2) X-ray in mammography technique in two planes; (3) computerized tomography (CT) with a density profile, and (4) magnetic resonance imaging (NMR). RESULTS: (1) Degree of deviation: Penile deviation ranged from 15 degrees to 63 degrees. It was best assessed using radiography in mammography technique reflecting the results obtained by autophotography. (2) Calcifications: Plaque calcifications were seen in 12 patients, 8 had no calcifications but thickening of the tunica albuginea only, 2 also had a fibrosis of the corpus cavernosum distant to the plaque. Calcifications were visualized using ultrasound sonography (12/12), radiographically (12/12), CT (12/12), NMR (9/12). Thickening of the tunica albuginea only was visualized using ultrasound sonography (7/8), radiographically (0/8), CT (2/8), NMR (6/8). (3) Morphological pattern in ultrasound: Three distinct patterns could be detected: (type 1) the plaque appeared as a thickening of the tunica albuginea without acoustic shadowing and only minimal density increase in the histogram profile; (type 2) moderately calcified plaque with typical ultrasound shadow but minimal density increase in the density profile; (type 3) severely calcified plaque with typical acoustic shadowing and density increase in the histogram profile. (4) Plaque inflammation: Only NMR with gadolinium DTPA showed periplaque inflammation. CONCLUSIONS: High-resolution ultrasound sonography is the best imaging modality in assessment of plaques. NMR is the modality of choice to monitor the inflamed plaque. X-ray in mammography technique and CT are not necessary in daily routine.

Testicular microlithiasis and concomitant testicular intraepithelial neoplasia.

We report a case of testicular microlithiasis developing during cancer follow-up in a previously normal testicle. Biopsy revealed testicular intraepithelial neoplasia which was treated with radiotherapy. We believe that especially in cancer follow-up newly developing microlithiasis must lead to biopsy to rule out otherwise undetectable germ cell neoplasia precursor.

Erectile dysfunction due to single vessel failure: diagnosis and surgical treatment.

We report on the successful surgical treatment of venous single vessel disease in a patient presenting with erectile dysfunction. We stress the necessity of accurate diagnostic workup which enables the identification of rare cases that can be cured surgically.

Fournier's gangrene: viability monitoring of subcutaneously transported testis following extensive debridement by color-coded duplex sonography and nuclear magnetic resonance.

We report the case of a subcutaneously transposed testis after surgical depridement for Fournier's gangrene. Its viability was successfully monitored using color-coded duplex sonography and nuclear magnetic resonance.

Assessment of the penile vascular system with color-coded duplex sonography and pharmacocavernosometry and -graphy in impotent men.

OBJECTIVE: To examine the extent to which color-coded duplex sonography permits complete clarification of vessel-dependent erectile dysfunction (ED). MATERIAL AND METHODS: A total of 215 patients with ED were examined. All patients underwent pharmacocolor-coded duplex sonography (PHCCDS; 20 micrograms of prostaglandin E1, PGE1, intracavernosally) as well as pharmacocavernosometry and -graphy (PHCM and PHCG; 20 micrograms of PGE1 intracavernosally). The penile vessels were visualized, i.e. the dorsal arteries, the cavernosal arteries, and the anastomoses between them, as well as the venous pathways. Peak flow and end-diastolic flow in all arteries and, when present, anastomoses were determined after stimulation. Induction flow to achieve maximal tumescence/rigidity as well as maintenance flow were determined during PHCM. Finally, for the morphological visualization of the cavenous body and possible venous insufficiencies, a radiography in 2 planes was produced with infusion of a water-soluble contrast medium. RESULTS: In 145 patients with a grade 0-III tumescence after stimulation with 20 micrograms of PGE1, PHCCDS revealed an end-diastolic flow of > 5 cm/s, with a peak flow velocity > 25 cm/s in the 2 cavernosal and 2 dorsal arteries. The deep dorsal vein of the penis was visualized in 110 of these 145 patients with a blood flow > 5 cm/s, and in 35 cases with a blood flow < 5 cm/s. Venous drainage to the corpus spongiosum was visualized in 80 patients with a blood flow > 10 cm/s. All patients had a pathologically increased induction (normal value < 100 ml/min) and maintenance venous flow (normal value < 10 ml/min) in the PHCM as well as venous drainage in the PHCG. Sixty patients with a tumescence grade of IV-V (rigidity) had a peak flow velocity clearly > 25 cm/s, an end-diastolic flow < 5 cm/s in the 2 cavernosal and 2 dorsal arteries in the PHCCDS, as well as induction values < 100 ml/min and maintenance flow values < 10 ml/min in the PHCM, without visible insufficient efferent venous pathways on the PHCG. In 29 patients (13.5%) hemodynamically active anastomoses perforating the tunica albuginea could be detected. Ten patients with a tumescence grade of III had a peak flow velocity < 25 cm/s and an end-diastolic flow < 5 cm/s without venous leakage in PHCM and PHCG. CONCLUSION: PHCCDS allows for the assessment of arterial flow disorder as well as of venous leakage in ED. PHCM and PHCG should only be carried out in patients in whom surgical or radiological interventional procedures at the efferent venous pathways are planned.

Leydig cell tumor--comparison of results of radical and testis-sparing surgery in a single center.

Between January 1981 and December 1995, 15 patients were treated for Leydig cell tumor at our institution -- 12 by radical orchiectomy, 3 by tumor enucleation. All patients were contacted to assess the long-term outcome depending on the treatment initially chosen. Follow-up ranged from 8 to 161 months (mean 56). In no case was progressive disease documented, in 1 case local recurrence was witnessed 4 months after tumor enucleation despite negative resection margins. We conclude that a small Leydig cell tumor can safely be managed by local enucleation alone.

Intravenous urography revisited in the age of ultrasound and computerized tomography: diagnostic yield in cases of renal colic, suspected pelvic and abdominal malignancies, suspected renal mass, and acute pyelonephritis.

The aim of our study was to assess the diagnostic yield of intravenous urography (IVU) compared to ultrasound (US) and computerized tomography (CT) in cases of renal colic, suspected pelvic and abdominal malignancies, suspected renal mass, and acute pyelonephritis. We retrospectively analyzed the case charts of 216 consecutive patients. The patients had been referred to the Department of Radiology by different hospital departments and local general practitioners. All had undergone clinical examination, US and IVU, in that order. When deemed necessary, conventional tomography was performed. Patients with renal masses also underwent CT. In cases without renal colic and normal US examination, the subsequent IVU failed to detect any further important pathology. Hydronephrosis was equally well detected using US and IVU, however, the level of obstruction was better determined using delayed X-ray films. In 24% of cases of renal colics the initial US was normal, however, the IVU revealed ureteric obstruction. Repeat US 8-12 h later always showed hydronephrosis. In 6 of 34 solid renal masses, IVU and conventional tomography failed to make the correct diagnosis, but never could the patient be spared a subsequent CT. IVU is only indicated if US shows hydronephrosis. In cases of renal colic, repeat US is necessary to diagnose the possibly developing hydronephrosis. Clinical history, US and a plain abdominal image will suffice to make the diagnosis. Renal masses always require CT. In these cases, IVU is not necessary. There is no indication left for conventional renal tomographies.

Local interferon-alpha 2b is not an effective treatment in early-stage Peyronie's disease.

OBJECTIVE: Peyronie's disease is characterized by an acquired penile deviation that may lead to severe penile deformity. It is refractory to most conservative therapy, and surgical correction is therefore the treatment of choice once the disease process has come to a halt. Basic science, as well as our first clinical results on the use of interferons (IFNs), have been promising, suggesting a beneficial effect in the early noncalcified disease stage. MATERIAL AND METHODS: From July 1994 to October 1995, 30 patients suffering from early Peyronie's disease were treated with three local injections of 3 million units of IFN-alpha 2b each into the plaque(s). The interval between the injections was 1 week. Patients were assessed clinically and ultrasonographically 6 months after the last injection. RESULTS: Peyronie's disease clinically improved in only 1 case, remained stable in 26 patients and worsened in 3. In 7 patients, a total of 10 plaques at different sites were detected. By ultrasonography the treated plaques now showed calcifications in 3 cases, remained unchanged in 26 and could not be detected in 1 case. Of the 10 new plaques, 2 showed calcifications. Side effects (myalgia, fever) were considerable; in 74 of 90 injections, fever > 38 degrees C occurred, and a total of 8 working days were lost. CONCLUSION: IFN-alpha 2b, given according to our regimen, is not useful for the treatment of Peyronie's disease in the early stage since the disease progress continues at different sites in about 25% of the patients, and the side effects are untolerable. Our results also demonstrate that local therapy is not indicated in Peyronie's disease.