Acoustic neuroma surgery: an eclectic approach with emphasis on preservation of hearing. The New York University-Bellevue experience

During the past 10 years, 157 patients have been operated on at the New York University-Bellevue Medical Center for acoustic neuromas and other cerebellopontine angle tumors. We describe our diagnostic protocol with joint neurosurgical evaluation leading to either translabyrinthine (otology only) or suboccipital-transmeatal (combined otology-neurosurgery) surgery. The decision is made on the basis of tumor size, level of hearing, age, and health of the patient. Using these criteria, 105 suboccipital and 59 translabyrinthine operations were performed with eight patients having had two-stage operations. In 12 of 29 patients, hearing was successfully preserved. Of 18 patients with good hearing and extracanalicular tumors less than 2 cm, hearing was preserved in 11. We describe the surgical technique used in this suboccipital-transmeatal operation and present illustrative cases in detail.

Circadian and circannual variations of FSH, LH, testosterone, dehydroepiandrosterone-sulfate (DHEA-S) and 17-hydroxy progesterone (17 OH-Prog) in elderly men and women

A group of 63 men and 86 women 77 +/- 8 years of age institutionalized at the Berceni Clinical Hospital, Bucharest, Romania, on a diurnally active living schedule with rest at night, eating 3 comparable but not identical meals a day, were investigated over a 2-year span in 278 profiles extending over a 24-hour span each and distributed over all our seasons. On each day of sampling six samples of blood were collected at 4-hour intervals beginning at 0800 of the first day of the study to 0400 of the next. Plasma testosterone, dehydroepiandrosteronesulfate (DHEA-S), 17-hydroxyprogesterone (17-OH Prog), FSH and LH concentrations were determined by radioimmunoassay. Statistically significant circadian rhythms were detected and quantified by population mean cosinor for the men and women of the entire group and for the age groups of 51 to 70 (I), 71 to 80 (II) and above 80 years of age (III) separately. Circannual rhythms of the circadian means were sought and evaluated by one way analysis of variance. Statistically highly significant circadian rhythms were found in plasma testosterone, 17-OH Prog and DHEA-S, concentrations in men and women of all three age groups with a phase advance of over 2 hours in DHEA-S with advancing age. Circannual cycles were found for plasma testosterone concentration and for DHEA-S in men and women, with a likely phase difference between men and women in testosterone. In LH a circadian rhythm was found in the women and in FSH in men only and a circannual variation in LH only in men.

Circadian rhythm in plasma immunoreactive somatomedin-C in children

Fifteen boys and 27 girls, 11 +/- 2 years of age were studied over a single 24-hour span during the month of June. Statistically significant circadian rhythms of plasma immunoreactive somatomedin-C (SM-C) concentration, immunoreactive growth hormone (hGH) and cortisol concentration were found, which show marked differences in timing. The highest values of somatomedin-C occurred in the early evening hours (acrophase 19:08) in contrast to growth hormone which showed its peak values during the night and cortisol, which peaked in the morning hours. These observations are of interest for the physiologic regulation of somatomedin-C as well as for the clinical evaluation of plasma immunoreactive somatomedin-C concentrations, and for studies of the response of somatomedin-C to hormonal and/or pharmacologic manipulation.

Persistently increased intestinal fraction of alkaline phosphatase

Persistent elevation of the intestinal fraction of the alkaline phosphatase (API) as an isolated finding has to our knowledge not been reported previously. It was found in a boy followed during a period of 5.5 years. The only symptom was transient periodic fatigue observed at home, but not apparent during hospitalization. His blood type was O, RH+, Le (a-, b+) and he was a secretor of H-substance, which may be associated with rising API activity after fat-loading. In this case API was unchanged after fat-loading. Neither intestinal nor liver diseases were found, and no other cause for the elevated phosphatase activity could be demonstrated.

[Electrochemical reduction of the anthracycline antibiotic 5-iminodaunorubicin. Isolation and structural clarification of the reduction products]

After electrochemical reduction of the potential cancer chemotherapeutic 5-iminodaunorubicine two new compounds, were isolated purely by chromatographic separation. Based on 1H-NMR, IR-, UV/VIS- and MS-investigations the one reaction product was identified as 7-desoxy-5-iminodaunorubicinone as expected, while the other was proofed as 9-acetyl-9,12-dihydroxy-4-methoxy-7,8,9,10-tetrahydroxy-6,11-naphthac enchinone.

Interaction of anthracycline antibiotics with biopolymers. VIII. Binding parameters of aclacinomycin A to DNA

The binding of aclacinomycin A to DNA was investigated spectrophotometrically under equilibrium conditions. The self-association behaviour of aclacinomycin A was identified as dimerization. Based on a model of overlapping potential binding sites the subsequent results were obtained: equilibrium constant of cooperative binding K = (7.58 +/- 2.15) X 10(6) M(-1), size of a binding site alpha = 3.98 +/- 0.14 base pairs, cooperativity parameter sigma = 0.12 +/- 0.10. These parameters were compared with those of adriamycin, daunomycin, and iremycin to draw some conclusions regarding the structural specialities of aclacinomycin A.

Circadian rhythm in urinary N-acetyl-beta-glucosaminidase (NAG) of clinically healthy subjects. Timing and phase relation to other urinary circadian rhythms

Urinary N-acetyl-beta-glucosaminidase (NAG), a lysosomal enzyme of renal tubular origin, has been shown to be a sensitive indicator of renal tubular function. This study documents a circadian rhythm in the urinary activity of NAG, statistically validated and quantified by the cosinor method, in 19 female and 15 male human subjects. The acrophase of the circadian rhythm in urinary NAG activity occurs at 09(40) with 95% confidence limits between 08(40) and 12(08) and is similar to the timing of the circadian rhythm in urinary free cortisol. The circadian acrophase of urinary NAG activity lags in timing the circadian rhythms in urine volume, Na and K excretion, and urinary free adrenalin and noradrenalin, by about five to ten hours and the circadian rhythm in creatinine excretion by about 11 hours. These functions with their characteristic phase relations are part of the internal circadian time structure of the human organism, and may provide internal phase references, independent of the "time of day." This study also documents a sex difference in mesor of the circadian rhythms in urinary NAG activity, with female subjects having a higher mesor and amplitude than the male subjects, and in the excretion of creatinine and potassium, with male subjects having a higher mesor and amplitude than the female subjects.

Electrochemical reduction pathways of anthracycline antibiotics

The preparative electrochemical reduction of a series of anthracycline antibiotics was performed using the technique of large scale electrolysis and d. c. polarography for recording different reaction pathways. The reduction products were identified by mass spectrometric and chromatographic analyses. Only anthracyclines with sugar residues in the C-10 position chromatographic analyses. Only anthracyclines with sugar residues in the C-10 position (iremycin, roseorubicin A) were reduced reversibly by 2e- to the corresponding hydroquinones. All others with sugar residues in the C-7 position (daunomycin, 5-iminodaunomycin, adriamycin, carminomycin, beta-rhodomycin II, aclacinomycin A, 1-deoxypyrromycin) showed an irreversible behavior because of the reductive splitting of the glycosidic bond after formation of 7-deoxy compounds or -- if the C-11 OH-group was not present -- of dimers, respectively.