Deep Brain Stimulation——A new treatment for tinnitus

Intractable tinnitus can lead to serious consequences. Study evidence indicates that the central nervous system is involved in generation and maintenance of chronic tinnitus and that tinnitus and other neurologic symptoms such as chronic pain may share similar mechanisms. Brain ablation and stimulation are used to treat chronic pain with success. Recent studies showed that ablation and stimulation in non-auditory areas resulted in tinnitus improvement. Deep brain stimulation (DBS) may be an alternative treatment for intractable tinnitus and deserves further study.     

Human calcium absorption from whole-wheat products

Fractional calcium absorption from wheat products and the influence of co-ingested wheat products on calcium absorption from milk were measured in a series of randomized crossover studies in healthy adult women. The wheat had been intrinsically labeled with 45Ca during growth. In the first study, fractional calcium absorption from leavened whole-wheat bread averaged 0.817 +/- 0.124. By comparison, absorption from milk, ingested at a comparable load in the same women, averaged only 0.589 +/- 0.111. When labeled bread was co-ingested with milk, at the same aggregate load as for bread alone, bread calcium absorption fell to 0.748 +/- 0.103 (P less than 0.05). In a second study, calcium absorption from an extruded cereal prepared from intrinsically labeled wheat bran was compared with milk. Calcium absorption from the cereal (0.223 +/- 0.046) was significantly less than from milk (0.375 +/- 0.072) (P less than 0.001). When the two were co-fed at the same total load, milk calcium absorption fell to 0.258 +/- 0.055 (P less than 0.001). In a third study, the effect of phytate hydrolysis through yeast fermentation and of Maillard browning on calcium absorption was investigated using leavened bread and underbaked and overbaked cookies, each made with intrinsically labeled wheat flour. Calcium absorption from cookies was not affected by the extent of browning and averaged 0.652 +/- 0.087. However, calcium absorption from bread in these same women averaged 0.703 +/- 0.108. This was significantly more than from the cookies (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Acquired supravalvar membranous stenosis of the left atrioventricular valve

Acquired supravalvar membranous stenosis of the left atrioventricular valve developed in a nine year old boy with atrioventricular discordance. The supravalvar membrane had not been present when a partial annuloplasty was performed on the left atrioventricular valve eight years before. The stenosis was relieved by operative excision of the membrane.     

Revascularization of the renal artery in renovascular hypertension with progressive renal insufficiency

Sixteen patients underwent surgical treatment for severe renovascular hypertension with rapidly progressive renal failure. These patients were assessed preoperatively with the measurement of serum creatinine and blood-urea levels (means 271 +/- 204 mumol/l and 15.6 +/- 10.3 mmol/l respectively), and renal clearances. 5 patients underwent aorto-renal bypass (bilateral in one case) and 11 patients were treated by autotransplantation of the kidney. Operative mortality was 6.2%. Early results were assessed at 1 and 6 months postoperatively. Renal function was normal in 8 patients, improved in 5 (p less than 0.05), unchanged in 1 and worse in 1 by aorto-renal bypass thrombosis. At long-term with a minimum follow-up of 12 months (mean 31 +/- 12 months), the initial improvement in renal function remained steady in 12 patients whilst 1 patient has gone on to hemodialysis. At middle and long-term, 81% of the patients were normotensive without medication or had improved blood pressure (p less than 0.001). These good results confirm the reversibility of renal ischemic lesions and support an aggressive attitude towards the use of revascularization in the surgical treatment of such patients with renovascular hypertension and renal failure.     

Chemical equivalence of two polyetherpolyurethane foams as a vehicle for povidone-iodine solution: kinetic model for the loss of available iodine

The loss of available iodine from povidone-iodine solution stored in contact with two different polyetherpolyurethane foams was monitored as a function of time and temperature. Statistical evaluation of the results for the four temperatures studied [ambient (25 degrees), 30, 45 and 55 degrees C] indicated the chemical equivalence of the two foams as storage and delivery systems for povidone-iodine solution in terms of solution stability. In addition, application of a first-order kinetic model to the data produced an acceptable fit. An Arrhenius-type evaluation of the resulting rate constants yielded a linear relationship which was shown to be useful for predicting loss of available iodine under ambient temperature conditions of storage.     

HLA-B*27 subtyping by PCR-RFLP in Spanish patients with ankylosing spondyiitis

Abstract: We describe the use of restriction analysis on PCR-amplified DNA for detecting all B*27 subtypes except B*2710 and B*2711 (i.e. from B*2701 to B*2709). After detecting B*27 by Sty I, double digestions consisting of Sty I plus another informative enzyme led to subtype assignment. We used mismatched primers to create restriction sites when necessary. The method avoids group-specific amplifications and other laborious optimization procedures. It was successfully tested on a panel of well characterized cell lines covering different B*27 subtypes. Then, we studied a group of 57 ankylosing spondyiitis patients and 746 controls from the south of Spain. B*27 showed a very strong association with the disease (OR=211.27, P=\0˜7). B*2702 and B*2705 distribution in controls (20% and 77.1%, respectively) differed from previously reported data in the Spanish population. We unexpectedly found the B*2707 allele in our population (one control).     

Pharmacokinetics of the 13C labeled anticancer agent temozolomide detected in vivo by selective cross-polarization transfer

The anticancer agent temozolomide labeled with ¹³C (8-Carbamoyl-3-13C-methylimidazo-[5,1-d]-1,2,3,5-tetrazin-4-(3H)-one), was noninvasively detected in subcutaneous RIF-1 tumors by a selective cross polarization ¹³C NMR method, at a field strength of 9.4T. Pharmacokinetics of the drug, at a dose of 150 mg/kg, were determined for intravenous and intraperitoneal modes of administration (three animals per mode). The half-life of the drug in the tumors was approximately 60 min. The uptake and clearance of the drug, however, varied significantly between individual hosts, for both modes of administration. These results demonstrate the feasibility of obtaining pharmacokinetics of anticancer agents for individual tumors without the need for a label that might modify drug activity (e.g., fluorine). The variability of the in vivo measurements, even within the same tumor model, demonstrates the necessity of directly monitoring the tumor to evaluate drug pharmacokinetics.     

Total cortisol,free cortisol,and growth hormone associated with brief social separation experiences in young macaques

Many behavioral, immunological, and physiological consequences of brief maternal separation in bonnet (Macaca radiata) and pigtail monkeys (Macaca nemistrina) have been documented. However, the impact of social separation on plasma cortisol and growth hormone is unknown for these particular species. In the present study, the behavioral and endocrinological consequences of a 2-week maternal separation in socially housed infant bonnet and pigtail monkeys were followed. In seven pairs (separated and matched control) of bonnet and six pairs of pigtail infants, plasma was obtained under baseline, separated, and reunion conditions twice weekly for the duration of the study. Blood samples were obtained from both infants of the pair in approximately 10 min. Plasma total cortisol, free cortisol, and growth hormone were measured in these samples. Focal animal behavioral observations were made on all subjects twice daily throughout the study period. In both species, total cortisol and free cortisol rose immediately following maternal separation in comparison to the matched nonseparated controls and returned to basal levels (e.g., that of matched non-separted controls) following reunion with the mother. In contrast, plasma growth hormone rose only in the pigtail infants over a time course that peaked around the time of reunion. Multiple regression techniques indicated for the first week of separation, in the separated but not control subjects, that mean plasma free and total cortisol was positively related to distress behaviors (vocalization and postural slouch) observed during this week and negatively related to social behaviors (play and proximity to others) noted during the same period. In contrast, plasma growth hormone was related to both species and sex of the subjects but unrelated to behavioral variables. © 1995 John Wiley & Sons, Inc.