A new continental hydrogen play in Damara Belt (Namibia).

Serpentinization is commonly presented as the main source of natural hydrogen (H2) in the continental domains. However, recent works in Australia and Brazil showed that Archean-Paleoproterozoic banded iron formations could be another natural source of H2 gas. Although the reaction that produces hydrogen is similar (Fe2+ oxidation-H2O reduction process), the iron content may be higher in banded iron formations than in mafic igneous lithologies, potentially generating H2 more efficiently. Here, we present structural evidence that reported H2 emissions from Waterberg Basin, Namibia are associated with underlying Neoproterozoic banded iron formations-the Chuos Formation. Magnetite, a known H2-generating mineral, is ubiquitous and accompanied by other suspected H2-generating minerals (biotite and siderite) in Chuos Formation. Magnetite occurs either as pervasive cm to dm continuous metamorphic laminations in foliation and fractures planes and/or diffusely disseminated in metachert and metacarbonate levels. From this, we infer that metamorphism does not negatively affect the Fe2+ content that is required to generate hydrogen. H2 seepages in Waterberg Basin suggest that an active H2-generating system may exist at depth and that the presence of potential traps and reservoirs is likely based on field observations.

Transurethral microwave hyperthermia in the treatment of chronic nonbacterial prostatitis.

Chronic nonbacterial prostatitis is an ill-understood and difficult-to-diagnose disease. Symptoms of chronic nonbacterial prostatitis are similar to those of chronic prostatitis and include low back pain, frequency, dysuria, perineal discomfort, and painful ejaculation. In view of uncertainty about etiology, treatment of chronic nonbacterial prostatitis remains speculative. Most treatment is aimed at relieving symptoms and not at curing the disease. Because of the troublesome nature of chronic nonbacterial prostatitis and the poor results obtained from traditional treatment methods, a new modality of transurethral microwave hyperthermia was investigated. Six patients were treated from January 1994 through June 1995 by use of transurethral microwave hyperthermia. These men were treated four times during a 2-week period. Their average symptom score decrease was 74.9% and was associated with minimal morbidity. Based on this result, it is concluded that transurethral microwave hyperthermia is a safe and effective treatment modality for chronic nonbacterial prostatitis.

Metastatic Sertoli cell carcinoma of the testis.

Metastatic Sertoli cell tumor is a very rare and deadly disease accounting for approximately 1% of all testicular carcinomas. With fewer than 30 cases reported in the literature, there has not been a uniform treatment regimen with good results. Retroperitoneal lymph node dissection, chemotherapy, and radiation therapy in combination appear to offer the best outcome. This report describes the occurrence of this rare tumor in a 38-year-old man 2 years after left orchiectomy.

Use of predeposited autologous blood plus intraoperative autotransfusion compared with use of predeposited autologous blood alone in radical retropubic prostatectomy.

The efficacy of combining preoperative autologous blood donation with the intraoperative use of an autotransfuser during radical retropubic prostatectomy was examined by retrospective analysis of the charts of 27 patients who underwent this procedure between February 1989 and August 1992. An intraoperative autotransfuser was combined with 2 units of predonated autologous blood in 14 patients (group 1), with 4 (29%) of the 14 requiring homologous blood. In group 2, 5 (62%) of 8 patients required homologous blood. For the remaining 5 patients (group 3), no autologous blood was available, so all received homologous blood transfusion. Preliminary data suggest that ideally, patients scheduled for radical prostatectomy should attempt to store at least 2 units of autologous blood and have an autotransfuser available during surgery.

Outpatient dobutamine therapy: the rhyme and the riddle.

Advances in critical care medicine have increased survival for victims of myocardial infarction and other acute cardiac events so that increasingly patients are receiving long-term, labor-intensive, and costly medical care. Innovations in drug delivery systems and skyrocketing health care costs have fostered the growth of home health care which has blossomed into a $2.8 billion industry. There is evidence that outpatient dobutamine therapy produces definite physical and possibly psychological improvements of variable degree and duration. Hemodynamic improvements are generally associated with improvement in functional class, and the financial savings are recognizably substantial. However, three major problems confront therapies with beta-adrenergic agonists: tendency for tolerance, ventricular arrhythmias, and increased myocardial oxygen consumption. There is a dire need for establishment of exclusionary patient criteria and for risk stratification, as well as for development of a portable radionuclide nonimaging monitor. Given the current fund of knowledge, outpatient dobutamine therapy should be undertaken cautiously after meticulous patient selection reflecting an awareness of the tremendous complexities and inherent risks. The therapeutic implications are dependent on the nature of the underlying cardiomyopathy and the fact that beta-adrenergic receptor desensitization is unlikely to be overcome by progressive dosage increases. Therapy is initiated with the understanding that treatment will remain blindly empirical and conjectural in the absence of a continuous physiologic monitor and an expanded comprehension of the molecular pathophysiology of the failing ventricle.