α-HUMAN ATRIAL NATRIURETIC POLYPEPTIDE REDUCES THE PLASMA ARGININE VASOPRESSIN CONCENTRATION IN HUMAN SUBJECTS

The synthetic alpha-human atrial natriuretic polypeptide (alpha-hANP) was infused into six normotensive, euvolaemic, healthy volunteers to examine the effect on the plasma arginine vasopressin (AVP) concentration. The intravenous administration of alpha-hANP (0.1 microgram/kg/min, 20 min) led to a remarkable reduction in mean blood pressure (-10 mmHg, P less than 0.05), and there was an increase in pulse rate (+10 bpm, P less than 0.05), in each subject. The urinary volume, sodium excretion and cyclic 3',5'-guanosine monophosphate (cyclic-GMP) excretion were increased to 3.5 (P less than 0.05), 2.5 (P less than 0.05) eight-fold (P less than 0.01), respectively, during the alpha-hANP infusion. The dose and duration of the synthetic alpha-hANP in the present study was sufficient to induce these cardiovascular and renal effects. The plasma AVP concentrations decreased from 0.39 +/- 0.09 pg/ml to the undetectable level during the alpha-hANP administration. After infusion, the plasma concentrations of the AVP promptly returned to preinfusion levels (0.46 +/- 0.14 pg/ml). However, there was no significant change in plasma AVP concentration during placebo infusion. The marked suppression in plasma AVP concentration may account for the remarkable diuresis, in addition of the direct renal effects of the synthetic alpha-hANP.     

Hepatic and renal expression of senescence marker protein-30 and its biological significance

A novel rat hepatic protein was detected and isolated, the amount of which is down-regulated in an androgen-independent manner with ageing. This protein was designated as senescence marker protein-30 (SMP30). Senescence marker protein-30 turned out to be identical to a hepatic calcium-binding protein called regucalcin (RC). This review gives an overview of SMP30 in its structure, expression and possible physiological function(s). A hypothetical role of SMP30 in ageing and calcium homeostasis is also discussed.     

Erosion of a penile prosthesis due to an indwelling urethral catheter as a late complication

A case of erosion of a penile prosthesis caused by indwelling of a catheter in the urethra is reported. A 73-year-old man had maintained sexual intercourse with penile prostheses (Jonas prosthesis, 19 cm) for 11 years without any complications until he developed cerebral infarction. One month after starting an indwelling urethral catheter in a neurosurgery clinic, the left-side penile prosthesis eroded from the area of the fossa navicularis, and was immediately removed. This type of complication is not unusual in patients with a neurogenic bladder. However, it is not well recognized in patients who suddenly develop a neurogenic bladder following a long-term uneventful period after the implantation of penile prostheses. Therefore, urologists should inform patients who receive this type of treatment that erosion of the prosthesis may develop when they need an indwelling urethral catheter as a late complication.     

Sagittal spinal alignment in patients with Legg-Calve-Perthes disease

BACKGROUND: Legg-Calve-Perthes disease (LCPD) is an avascular necrosis of the capital femoral epiphysis in children. Several studies found a pathophysiological relationship between LCPD and juvenile Scheuermann's kyphosis, suggesting an abnormal spinal condition related to osteochondrogenesis. In the present study sagittal spinal alignment of the patients with LCPD was analyzed to examine associated spinal involvement. METHODS: A standing lateral radiograph of the spine was evaluated in 78 patients who had a history of LCPD. Various parameters of sagittal spinal alignment, including thoracic kyphosis (TK), lumbar lordosis (LL), sacral inclination (SI), apex of thoracic kyphosis (TK-apex) and lumbar lordosis (LL-apex), and sagittal balance (SB; positive SB values represent a sagittal balance in front of the sacrum) were measured and compared between the patients with and without vertebral abnormalities. RESULTS: Compared to previously published normative data, relatively decreased LL was evident in LCPD. Most of the patients (65%) had negative SB, which was correlated with decreased SI, more proximal TK-apex, and more distal LL-apex. Vertebral abnormalities including end-plate irregularities and wedging vertebrae were observed in 20 patients. Decreased SI, more distal LL-apex, and more negative SB were remarkable in the patients with vertebral abnormalities. CONCLUSIONS: The patients tended to stand in greater negative sagittal balance associated with decreased LL. The characteristic sagittal alignment was prominent especially in the patients with vertebral abnormalities. Wedging vertebrae, probably due to growth disturbance of the vertebral bodies, could result in decreased LL, which leads to posterior pelvic tilt and posterior shift of sagittal balance.     

HYDROGEN-TRITIUM EXCHANGE TITRATION OF THE HISTIDINE RESIDUES IN BOVINE HEART CYTOCHROME C AND ANALYSIS OF THEIR MICROENVIRONMENT

Microenvironments of the three histidine residues located at the positions 18, 26, and 33 from the amino terminus in bovine heart cytochrome c were analysed in solution by the hydrogen-tritium exchange titration method, which has been developed in this laboratory. Histidine-18, which is liganded to the heme iron, and histidine-26 did not incorporate tritium in native state, indicating that the two are located in solvent inaccessible hydrophobic regions. Histidine-33 was labeled with tritium to an appreciable extent and seemed to be partially buried in the molecule. The pKa value estimated for histidine-33 was 6.1 at 37° by the tritium exchange titration, suggesting that the residue interacts very weakly with a neighboring cationic group. These results seem to be compatible with the tertiary structure of the protein deduced from the X-ray crystallographic analysis.     

Fetal Inclusion: Report of Two Cases and Review of the Literature and Diagonostic Criteria

ABSTRACT  Two cases of fetal inclusion were presented and 27 cases ever reported in Japan were reviewed. The first case presented had placental component and highly differentiated visceral organs in addition to the vertebral column and skin covering the included mass. The second case also had vertebral column and skin but the organoid pattern was not so clear as seen in the first case. It was most important to differentiate included fetus from teratoma in this second case and in some cases reviewed here, in which an orderly arranged visceral organ was not noted. Thus, diagnostic criteria described by Ohkawa et al was revaluated on the basis of embryological consideration and then it was concluded that included fetus could be diagnosed only by the presence of vertebral column and skin covering the included mass. Finally, it is proposed that fetal inclusion may be regarded as an acardiac structure embodied in the autosite.