Chiral polyoxotungstates. 1. Stereoselective interaction of amino acids with enantiomers of [Ce(III)(alpha1-P2W17O61)(H2O)x]7-. The structure of DL-[Ce2(H2O)8(P2W17O61)2]14-.

The ammonium salt of the 1:1complex (1) of Ce(III) with alpha(1)-[P(2)W(17)O(61)](10)(-) was prepared and characterized by elemental analysis, vibrational and NMR spectroscopy ((31)P, (183)W), cyclic voltammetry, and single-crystal X-ray analysis (P1; a = 15.8523(9) A, b = 17.4382(10) A, c = 29.3322(16) A, alpha = 99.617(1) degrees, beta = 105.450 (1) degrees, gamma = 101.132(1) degrees, V = 7460.9(7) A(3), Z = 2). The anion consists of a centrosymmetric head-to-head dimer, [[Ce(H(2)O)(4)(P(2)W(17)O(61))](2)],(14-) with each 9-coordinate Ce cation linked to four oxygens of one tungstophosphate anion and to one oxygen of the other anion. On the basis of P NMR spectroscopy, a monomer-dimer equilibrium exists in solution with K = 20 +/- 4 M(-1) at 22 degrees C. Addition of chiral amino acids to aqueous solutions of 1 results in splitting of the (31)P NMR signals as a result of diastereomer formation. No such splitting is observed with glycine or DL-proline, or when chiral amino acids are added to the corresponding complex of the achiral alpha(2)-isomer of [P(2)W(17)O(61)](10)(-). From analysis of the (31)P NMR spectra, formation constants of the two diastereomeric adducts of 1 with L-proline are 7.3 +/- 1.3 and 9.8 +/- 1.4 M(-1).

Biomechanic evaluation of the Rola Stretcher as a passive distraction device.

INTRODUCTION: Many devices have been marketed claiming to increase the mobility of the articulations of the spine with active or passive distraction. In this study, the Rola Stretcher (Unique Relief, Inc, Davenport, Iowa) and an earlier version, the True Back II (True Back, Inc, Clearwater, Fla), were evaluated to see if they have a measurable biomechanic effect on the spine. METHODS: Two studies were conducted, each with 6 male participants and 6 female participants, using a stadiometer to accurately measure a person's sitting height. The increase in sitting height after using the True Back II or Rola Stretcher for 10 minutes was compared with that after lying supine for 10 minutes. A third intervention, a firm foam block cut to the same size and shape as the True Back II, was also used in this study. RESULTS: The Rola Stretcher had a significantly greater lengthening effect on the spine compared with supine rest (P <0050). The True Back II had a similar but lesser effect (P <.0509). Women demonstrated a greater height gain than men. CONCLUSION: The True Back II and the Rola Stretcher in particular appear to lengthen the spine after a single use of 10 minutes. The observed discrepancy between the effects in men and women may be an experimental artifact occurring as a result of less effective resetting of the posturing mechanisms in men compared with women. A trend showed the Rola Stretcher to be more effective than the foam block.

Relaxin and decidualization in mice: a reappraisal.

The nature of the physiological stimulus inducing decidualization in the endometrium is unknown. In this study we attempted to verify a recent report that relaxin can induce decidualization in intact mice primed with a high dose of estradiol valerate (5 micrograms) and a low dose (10 micrograms) of medroxyprogesterone acetate. In our study, neither s.c. nor intrauterine relaxin, nor intraluminal arachis oil, (an established deciduogenic stimulus) were able to induce decidualization. In addition, while oil was able to induce decidualization (increased uterine weight, and positive Pontamine Sky Blue and stromal alkaline phosphatase reactions) in ovariectomized mice treated with a regimen of estradiol and medroxyprogesterone acetate designed to produce optimum uterine sensitivity, no decidualization occurred in response to either s.c. or intraluminal relaxin. This study fails to provide any support for a role for relaxin as a deciduogenic stimulus.

A prospective randomized three-week trial of spinal manipulation, transcutaneous muscle stimulation, massage and corset in the treatment of subacute low back pain.

STUDY DESIGN: A randomized prospective trial of manipulation, massage, corset and transcutaneous muscle stimulation (TMS) was conducted in patients with subacute low back pain. OBJECTIVES: The authors determined the relative efficacy of chiropractic treatment to massage, corset, and TMS. SUMMARY OF BACKGROUND DATA: Although all of these treatments are used for subacute low back pain treatment, there have been few comparative trials using objective outcome criteria. Patients were enrolled for a period of 3 weeks. They were evaluated once a week by questionnaires, visual analog scale, range of motion, maximum voluntary extension effort, straight leg raising and Biering-Sorensen fatigue test. The dropout rate was highest in the muscle stimulation and corset groups and lowest in the manipulation group. Rates of full compliance did not differ significantly across treatments. A measure of patient confidence was greatest in the manipulation group. RESULTS: After 3 weeks, the manipulation group scored the greatest improvements in flexion and pain while the massage group had the best extension effort and fatigue time, and the muscle stimulation group the best extension. CONCLUSION: None of the changes in physical outcome measures (range of motion, fatigue, strength or pain) were significantly different between any of the groups.

Longitudinal evaluation of communication skills of children with single- or multichannel cochlear implants.

Performance on speech perception, speech production, and language tests was measured over time in children who used the 3M/House or the Nucleus cochlear implant. The speech perception and production results demonstrated higher performance levels and faster rates of learning for the multichannel than for the single-channel users. The performance of the children with the single-channel implant on the speech perception and production measures reached a plateau by 1.5 years post implant, whereas the children using the multichannel device continued to show improvement after 2 or more years of implant use. Changes in language were limited over time with no obvious difference in performance as a function of type of implant.

Timing of the window of uterine sensitivity to decidual stimuli in mice.

The refractory period that follows the period of sensitivity to a decidual stimulus in ovariectomized hormone treated mice was investigated. Medroxyprogesterone acetate provided constant progestin concentrations and silastic implants containing oestradiol maintained constant nidatory oestrogen concentrations. The nidatory stimulus was provided by crushing the uterus with a haemostat or by the intrauterine instillation of arachis oil. The decidual response was assessed by measuring changes in uterine weight or by examining the stroma for the presence of alkaline phosphatase. Sensitivity to the oil was first observed approximately 14 h after the insertion of the oestradiol implant but this sensitivity had waned by 32 h and was absent at 40 h. Crushing the uterus initiated a decidual response in mice treated with progestin alone but if the oestradiol implant was inserted then the uterus was responsive to crushing 24 h after insertion but not at 45 h. The traumatic decidual cell reaction (crushing), although not requiring nidatory oestradiol for its successful initiation, was nevertheless subject to the refractoriness that followed oestradiol sensitivity.

Functional outcomes of low back pain: comparison of four treatment groups in a randomized controlled trial.

The revised Oswestry Low Back Pain Questionnaire (ROLBPQ) and Roland-Morris Activity Scale (RMAS) were compared in a randomized controlled trial of chiropractic manipulation, stroking massage, corset and transcutaneous muscular stimulation (TMS). This trial employed specific inclusion and exclusion criteria, including nonspecific low back pain for a duration of 3 wk to 6 months and ages between 18 and 55. We had the opportunity to ask 85 patients to answer the questionnaires. Sixty-three patients, who completed the initial and final evaluations, were used for data analysis. Both ROLBPQ and RMAS showed good internal consistency with alpha coefficients ranging from .77 to .93. Both instruments showed a significant difference between the chiropractic manipulation and massage groups (p less than .05). RMAS was able to further show significant differences between the chiropractic manipulation and TMS groups, and between the corset and massage groups, but the ROLBPQ failed to do so. RMAS also showed that chiropractic manipulation had a better but nonsignificant result than corset, possibly due to insufficient sample size and/or duration of treatment. We conclude that both instruments are reliable for measuring low back pain disability, and chiropractic manipulation has a superior short-term benefit when compared to stroking massage and TMS in subacute low back pain patients. In addition, it appears that RMAS is preferable in a clinical trial situation for subacute low back pain because it is more sensitive than ROLBPQ to detect changes.

Infiltration of neutrophil polymorphonuclear leucocytes into the endometrial stroma at the time of implantation of ova and the initiation of the oil decidual cell reaction in mice.

Polymorphonuclear leucocytes (polymorphs) were found in the endometrial stroma adjacent to implanting blastocysts approximately 100 h after mating. Areas of uterus not containing a blastocyst had very few polymorphs. Ovariectomized mice were treated with hormones to render them sensitive to a decidual stimulus, the intraluminal injection of arachis oil. Areas of uterus responding to the oil (as indicated by the Pontamine Sky Blue reaction) showed an influx of leucocytes into the endometrial stroma between 16 and 36 h after the application of the decidual stimulus. The polymorphs were largely neutrophils. The injection of oil into non-sensitized uteri did not result in polymorph infiltration nor did the injection of physiological saline (which is not deciduogenic) into sensitized uteri. It is concluded that during the early stages of decidualization there is attraction of polymorphs from the blood into the stroma.

A study of the early morphological changes initiated in the uterine luminal epithelium by substances (oil and carrageenan) which induce the decidual cell reaction in mice.

Oil, carrageenan or saline were injected into the uteri of ovariectomized mice treated with hormones on schedules which would sensitize, partly sensitize or not sensitize the uterus to an intraluminal decidual stimulus. The uterine epithelium was examined histologically at various times over the succeeding 5 h. Saline did not produce any morphological change whereas almost immediately after the injection of oil or carrageenan epithelial cell death was apparent in the uterus, regardless of hormone treatment. Within 45 min the dead cells had been removed and the epithelium was re-established. Oil droplets were still present in the uterus after 5 h and these were able to stimulate a decidual reaction in partly sensitized animals when oestrogen was administered 18-44 h after the oil instillation, well after the re-establishment of the epithelium. It is suggested that the early transient cell death in the uterine epithelium is not responsible for triggering the decidual reaction but that it is the contact of the oil droplet with an intact epithelium which triggers the response when the hormonal conditions so allow.

Control of leucocyte infiltration into the decidualized mouse uterus.

Ovariectomized mice were treated with oestrogen and progesterone on a schedule to mimic early pregnancy. Decidualization was induced with oil and uteri were examined at various times after the last progesterone injection. The first morphological change detected in the uterus of decidualized mice following withdrawal of progesterone was infiltration of leucocytes into the stroma. This preceded overt tissue breakdown and extravasation of blood cells, and did not occur following withdrawal of progesterone without decidualization. It is suggested either that there is a release of a chemoattractant from decidual cells before any morphological changes are apparent or that the signal for attracting the leucocytes is released at the time of decidual induction, but that their migration is suppressed by progesterone.

Transcutaneous muscle stimulation to retard disuse atrophy after open meniscectomy.

Immobilization of an extremity inevitably results in disuse muscle atrophy. The effectiveness of transcutaneous muscle stimulation by a portable device in preventing atrophy has been determined. Ten patients treated by open meniscectomy and given the usual isometric training were matched with ten patients in whom electrostimulation, consisting of a strong, tetanizing, five-second sustained muscular contraction about 400 times/day, was used for two weeks. Muscular strength and leg circumference were measured before surgery and four weeks after surgery. The electrically stimulated group had a significantly smaller loss of muscle volume and muscle strength, were able to walk earlier without crutches, had a greater range of knee motion, had much less postoperative knee swelling, and used significantly less pain medication. Transcutaneous electrical stimulation may prevent muscle atrophy due to immobilization, thereby shortening rehabilitation time.

Transcutaneous muscle stimulation as a method to retard disuse atrophy.

Thirty healthy, young adults (18 to 25 years of age), were volunteers in a three-group study to determine the efficacy of transcutaneous electrostimulation as a means of preventing atrophy of normal musculature on wearing a long-leg cast. Each group of ten subjects (five males and five females) were chosen by lot: Group I, nonisometric, Group II, isometric, Group III, TMS electrostimulated thigh and calf muscles. There was little difference in the findings in Groups I and II, and each lost an appreciable amount of muscle mass and power after just two weeks of immobilization. However, in the electrostimulated group muscle atrophy was one-half that of the other groups in the thigh area and one-fifth that of the others in the calf area. In addition, the calf musculature retained its bulk and power with actual increase in a few of the less athletic individuals. Trancutaneous muscle stimulation offers great promise for surgically treated or impaired extremities, enabling early return to activity with optimal function.