Stabilization investment template for direct casting connection of implant framework segments

Diastolic Doppler filling parameters were measured before and after hemodialyses, performed once with and once without fluid removal. Changes occurred only with fluid removal and correlated with weight loss, indicating that they are the result of reduction in preload.     

Inferior alveolar nerve repositioning in implant dentistry: a preliminary report

The surgical repositioning of the inferior alveolar nerve facilitates the placement of implants in the posterior mandible. The entire height of the posterior mandible is made available and enables implants to be anchored in two cortical plates, improving the primary fixation and increasing the area of the bone-implant interface. The posterior mandible can thus be predictably treated with implants in those cases where posterior support is considered important for occlusal stability and masticatory efficiency. The rapid and total recovery of sensation to the lip following nerve repositioning renders the procedure more acceptable to both the patient and the clinician.     

Therapy for vaginismus: in vivo versus in vitro desensitization

OBJECTIVE: To verify the effectiveness of desensitization exercises with dilators in the treatment of vaginismus, while comparing 2 therapeutic variations with differing instruction procedures ("in vivo" versus "in vitro") during the desensitization exercises. METHOD: A consecutive random sample of 44 female outpatients in sexual therapy were divided into groups for either treatment on a random basis. All patients were treated until the symptoms abated on the basis of a structured therapy program. The stability of the therapeutic success was verified through follow-up interviews. RESULTS: Forty-three (97.2%) of the patients were able to have sexual intercourse after an average of 6.3 therapeutic sessions. One-third reported an increase in their sexual desire. Thirty-four of 39 patients (87.2%) would be prepared to repeat the therapy. There were no significant differences in the success and the required number of consultations for the cure between the 2 groups investigated. CONCLUSIONS: Desensitization through exercises with dilators is an effective method for treating vaginismus. The choice of instruction procedure can be left to the patient.     

HYOMEX: a miniature universal testing machine for in vivo biomechanical studies

A miniaturized universal testing machine, HYOMEX, designed for biomechanically testing spinal structures of an anaesthetized research animal, such as a pig, is presented. A variety of mechanical applications such as static and dynamic tests, creep and relaxation tests, and fatigue tests with frequencies up to 20 Hz are possible. The system permits force control as well as displacement control. Continuous surveillance is made possible through interfacing the system to a computer. An application is presented where the viscoelastic behaviour in a porcine lumbar spine was measured.     

Azocrosslinked poly(acrylic acid) for colonic delivery and adhesion specificity: in vitro degradation and preliminary ex vivo bioadhesion studies

This study reports on the performance of a novel polymeric material that is capable of providing site specificity in active agent delivery and the development of mucoadhesive interactions. Azo-networks, based on an acrylic backbone crosslinked with 4,4'-divinylazobenzene, were subjected to in vitro degradation and mucoadhesion (before and after degradation) testing in order to model their performance in the gastrointestinal tract. Advanced surface characterisation techniques (SEM, AFM, FTIR microscopy) were used to examine the network morphology prior to, and after degradation. The data obtained from these studies indicate that there is an optimum crosslinking density to allow non-adhesive particles to reach the colon. Within the colonic environment, the azo network degrades to produce a structure capable of developing mucoadhesive interactions with the colonic mucosa.     

Machining and accuracy studies for a tibial knee implant using a force-controlled robot

The use of thoriated tungsten electrodes may be at the origin of a potential hazard for the personnel involved in the use of electrodes, as well as the general population. To assess this hazard, the electrode radioactivity measurements by alpha and beta counting has been conducted. The radioelements were identified by alpha and gamma spectromety. It appeared that there was a radioactive disequilibrium between thorium-232 (Th-232) and it daughters atoms. Additionally, some thorium 230 (Th-230) belonging to the uranium chain, was present. The chemical separation and the milling processing had affected the radioactive composition and the thorium in the electrodes, doesn't exactly corresponds to natural thorium. Radiation doses were also assessed: film and photoluminescence dosimetry were undertaken. Finally smears method showed a alpha removable area contamination. Even if the hazard is weak. As a matter of fact, it must not be neglected because it was complex, for the thorium was always accompanied by Th-232 progeny, alpha emitters but also beta and gamma emitters.     

MR guidance of laser disc decompression: preliminary in vivo experience

BACKGROUND: The mechanism of atrial natriuretic peptide (ANP) release has been difficult to demonstrate in patient studies because of inaccuracies in measuring atrial volumes using conventional techniques. METHODS: Magnetic resonance imaging was performed in 28 clinically stable patients (New York Heart Association class 3) with chronic heart failure to determine right atrial (RA), left atrial (LA), and ventricular volumes. In addition, right heart catheterization was serially performed and plasma ANP levels (in picograms per milliliter) were drawn from the right atrium. RESULTS: Five patients had to be excluded from data analysis for technical reasons. The remaining 23 patients had the following hemodynamic measurements (mean +/- SD): RA mean pressure 7+/-5 mm Hg, pulmonary artery mean pressure 28+/-10, pulmonary capillary wedge pressure 21+/-8 mm Hg, and cardiac index 2.9+/-1.4 (L/min/m2), respectively. Plasma ANP levels were significantly elevated at 162+/-117 (normal range 20 to 65 pg/ml, p < 0.05), as were LA and RA volumes compared with healthy controls (RA volume 128+/-64 ml vs 82+/-25 ml, p < 0.05; LA volume 157+/-54 ml vs 71+/-24 ml, p < 0.01, respectively). ANP showed a stronger relation with atrial volumes (RA volume, r = 0.91, p = 0.0001; LA volume, r = 0.80, p = 0.001) than with atrial pressures (RA mean pressure, r = 0.45, p = 0.03; pulmonary capillary wedge pressure, r = 0.67, p = 0.001). A subgroup analysis of patients with increased RA or LA volumes (>1 SD of mean of controls) revealed a stronger relation between ANP and RA volumes than between ANP and LA volumes. CONCLUSIONS: These data suggest that increased right heart volume with subsequent increased atrial stretch is the major determinant for ANP release in patients with stable CHF.     

Niosomes as carriers for ophthalmic drugs: in vitro/in vivo evaluation

This report provides X-ray diffraction and Raman spectral evidence that, when 2,6-dichlorobenzonitrile is present in the culture medium, Acetobacter xylinum, which is a model system for investigation of the biosynthesis of native cellulose, produces cellulose II, as well as cellulose I. The significance of the observations with respect to the mechanism of biosynthesis of cellulose is discussed briefly.     

Combining cognitive testing and informant report to increase accuracy in screening for dementia

OBJECTIVE: Cognitive testing and an informant report questionnaire were combined to determine whether their use in combination could improve accuracy in screening for the diagnosis of dementia over either test used alone. Methods of combining test scores that can be readily applied in clinical settings were developed and assessed. METHOD: The subjects were 106 patients admitted to the geriatric hospital or outpatients assessed at the memory clinic of the university hospital system in Geneva, Switzerland. The instruments used were the Mini-Mental State and the short form of the Informant Questionnaire on Cognitive Decline in the Elderly. The diagnosis of dementia was made according to DSM-IV criteria. RESULTS: Logistic regression demonstrated that the combination of the Mini-Mental State and the Informant Questionnaire on Cognitive Decline in the Elderly resulted in more accurate prediction of caseness than either test alone. The performance of logical "or" and "and" combinations of test results and a weighted sum of scores on the two tests as screens for dementia were investigated by using receiver operating characteristic analysis. By using suitable cutoff points, both the "or" rule and the weighted sum were shown to be capable of improving performance over that of either test used alone. CONCLUSIONS: This study shows that informant report can be formally incorporated into assessment for dementia in such a way as to increase the accuracy of detection of cases and noncases. A graphical method was developed that enables the most robust approach to be applied to individual cases without any calculation.     

A dynamic modal testing technique for noninvasive assessment of bone-dental implant interfaces

A dynamic modal testing technique has been developed to noninvasively assess the interface surrounding an endosseous dental implant with a lateral tap from an impedance head hammer. The technique assesses the rotational stiffness of the interface based on the shape of the power spectrum of the force-time curve produced on impact. In vitro experiments were performed to determine the sensitivity of the technique for detecting clinically relevant structural differences between interfaces. The modal test data were able to distinguish interfaces based on the type of bone at the interface and the degree of fixation between the implant and the interface.     

Intracavitary ultrasound phased arrays for prostate thermal therapies: MRI compatibility and in vivo testing

A 62 element MRI-compatible linear phased array was designed and constructed to investigate the feasibility of using transrectal ultrasound for the thermal therapeutic treatment of prostate cancer and benign prostatic hyperplasia. An aperiodic design technique developed in a previous study was used in the design of this array, which resulted in reduced grating lobe levels by using an optimized random distribution of unequally sized elements. The element sizes used in this array were selected to be favorable for both grating lobe levels as determined by array aperiodicity and array efficiency as determined by width to thickness ratios. The heating capabilities and MRI compatibility of the array were tested with in vivo rabbit thigh muscle heating experiments using MRI temperature monitoring. The array produced therapeutic temperature elevations in vivo at depths of 3-6 cm and axial locations up to 3 cm off the central axis and increased the size of the heated volume with electronic scanning of a single focus. The ability of this array to be used for ultrasound surgery was demonstrated by creating necrosed tissue lesions in vivo using short high-power sonications. The ability of the array to be used for hyperthermia was demonstrated by inducing therapeutic temperature elevations for longer exposures. Based on the acoustic and heating performance of this array, it has the potential to be clinically useful for delivering thermal therapies to the prostate and other target volumes close to body cavities.     

Endogenous inhibitors of human choline acetyltransferase present in Alzheimer's brain: preliminary observation

We have previously demonstrated the presence in Alzheimer's disease brain of an endogenous inhibitor of choline acetyltransferase activity. Selected properties of these compounds were investigated. There appear to be two distinct classes of inhibitor present, both phosphomonoesters and nonphosphorylated substances. They are not proteins, pass through 500 mm dialyses membranes and are not lipoidal. There are both different sensitivities of individual control cytosotic activity to inhibition and differences in intrinsic inhibitory activity present in individual Alzheimer's disease brain samples. There is a competitive type of inhibition with respect to acetyl CoA as substrate and a noncompetitive type with respect to choline as substrate.     

Invited perspective: in vitro testing in developmental toxicity risk assessment

A surgical intervention is needed in patients with periodontal pouches deeper than 4-5 mm. The results of 239 operations in 182 patients are analyzed. Optimal variants of the operations are described, depending on the patient's status, analgesia, types of secondary adentia, surgical access, and intervals between the operations.     

Biodegradable polyesters for controlled release of trypanocidal drugs: in vitro and in vivo studies

Copolymers of epsilon-caprolactone and L-lactide P(CL-LLA), epsilon-caprolactone and D,L-lactide P(CL-DLLA) and epsilon-caprolactone and trimethylene carbonate P(CL-TMC) were synthesized. The composition of comonomers and their sequence lengths were determined by means of 1H and 13C NMR measurements. The effect of the comonomer on the thermal properties was investigated by differential scanning calorimetry (DSC) analysis. The in vitro degradation of the rods obtained by melt extrusion of the synthesized copolymers and the commercial homopolymers poly(epsilon-caprolactone) P(CL) and poly(D,L-lactide) P(DLLA) was carried out in phosphate buffer (PB) pH 7.4 at 37 degrees C. The rate of degradation depends on comonomers and polymer composition. The in vitro release of the selected drugs, isometamidium chloride (IMM) and ethidium bromide (EtBr), from such devices was carried out under the same conditions as used for the in vitro degradation. The release experiments show that the release of IMM is faster than for EtBr. During the first stage, for IMM the release is governed by osmotic pressure whereas for EtBr the release is mainly diffusion-controlled. The in vitro release of these drugs is governed by polymer matrix degradation at the later stage of the release process. Comparative in vitro release study from the different polymers showed that the release depends mainly on the physical properties of the polymer. The in vivo experiments carried out in the field on cattle and in the laboratory on rabbits using the classical treatment (intramuscular injection) and the sustained release devices (SRD) subcutaneously implanted, showed that the prophylactic period is significantly enhanced in the case of SRD as compared to intramuscular injection. The comparative efficacy of SRD containing IMM and EtBr evaluated in the case of rabbits showed that, the SRD (IMM) prophylactic period is much longer than for SRD (EtBr).     

Calcitriol modulates in vivo and in vitro cytokine production: a role for intracellular calcium

Calcitriol modulates in vivoand in vitro cytokine production: A role for intracellular calcium. Background. Several immunomodulatory properties of calcitriol are currently known, however, only little information is available regarding the in vivo and in vitro effects of calcitriol on cytokine production in chronic renal failure. Methods. To study the in vitro effect of calcitriol on lipopolysaccharide (LPS)-induced cytokine production, peripheral blood mononuclear cells (PBMC, 2.5 ml/ml) from 12 chronic dialytic (HD), 15 undialyzed chronic renal failure (CRF) patients and 10 normal subjects (N) were incubated at 37 degrees for 12 hours with 100 ng of LPS (E. coli and P. maltofilia). Increasing doses of calcitriol from 10-10 to 10-9 M were added and cell associated TNF-alpha and IL-1beta were determined by immunoreactive tests after three freeze-thaw cycles. The intradialytic TNF-alpha and IL-1beta production were evaluated in vivo in 12 HD patients before and after three months of intravenous calcitriol treatment (6 microgram/week). Intracellular calcium [Ca++]i was determined on PBMC with a cytofluorimetric assay using FLUO-3 AM as the indicator. Results. In vitro, TNF-alpha increased from 3.6 +/- 1.9 pg/cell to 1797 +/- 337 in N, from 4.5 +/- 1.7 to 1724 +/- 232 in CRF and from 3.4 +/- 2.3 to 1244 +/- 553 in HD after the LPS stimulus. The production of TNF-alpha was inhibited by calcitriol in a dose-dependent manner [LPS + Vit.D3 100 ng, 2.9 +/- 2.1 in N, 3.7 +/- 1.9 in CRF and 3.4 +/- 1.7 in HD; LPS + Vit.D3 50 ng, 263 +/- 296 (N), 6.73 +/- 11 (CRF), 38 +/- 28 (HD); LPS + Vit.D3 25 ng = 873 +/- 583 (N), 325 +/- 483 (CRF), 588 +/- 507 (HD); LPS + Vit.D3 12.5 ng, 954 +/- 483 (N), 912 +/- 510 (CRF), 875 +/- 527 (HD)]. Comparable data were observed on IL-1beta production. In vivo, the intradialytic TNF-alpha increase (from 8.5 +/- 2.3 to 19 +/- 5.6 pg/2.5 x 106 cell) during hemodialysis was markedly reduced after calcitriol therapy (from 6.6 +/- 3.1 to 11 +/- 4.7). [Ca++]i decreased from 105 +/- 25 to 72 +/- 18 nM (P < 0.05) and a positive correlation between cytokine levels and [Ca++]i was found (r = 0.79; P < 0.001). Conclusions. The in vitro increase of cell-associated cytokine after LPS challenge was inhibited by calcitriol in a dose-dependent manner. These data suggest a possible in vivo modulatory effect of calcitriol therapy on cytokine production in hemodialysis.     

Recruitment of tissue resident cells to hydrogel composites: in vivo response to implant materials

A model of local cellular recruitment was established using hydrogel matrices composed of alginate implanted subcutaneously into mice. Cells which trafficked to the matrix blocks were recovered and characterized for surface phenotype using fluorescently labelled antibodies and flow cytometry (fluorescence activated cell sorting). Temporal information of the differential recruitment of cells was determined. The basic pattern of recruitment in response to the hydrogels was established and mimicked that seen in a local inflammatory response. Neutrophils (PMN) were rapidly recruited (1 d) followed by macrophages and lymphocytes (1-3 d). Cell surface phenotype studies included the determination of CD3+, CD4+ and CD8+ cells, Mac-1+ cells, and immunoglobulin bearing cells. Microscopic analysis revealed numerous activated PMNs and monocyte derived foamy macrophages. Fluorescence immunocytochemistry of frozen sections of the block revealed that macrophages, CD3+ and natural killer cells were all recruited to the interior of the block. Ultrastructural analysis (transmission electron microscopy) showed highly activated macrophages, with abundant rough endoplasmic reticulum and secretory vesicles. Cells which remained on the surface of the matrix block were CD44 positive migratory cells. Electron microscopic evidence showed foamy macrophages with a varying degree of involvement with the hydrogel material. Surface scanning electron microscopy revealed numerous fibroblast-like cells coating the surface of the block. We suggest that these methods may be used to address the inflammatory response elicited with a a variety of implanted materials such as hydrogels, silicones, ceramics and metals. Furthermore, this model has been useful in determining cellular responses to cytokines and growth factors under similar conditions.     

Speed and accuracy of facial expression classification in avoidant personality disorder: A preliminary study.

The aim of this preliminary study was to examine whether individuals with avoidant personality disorder (APD) could be characterized by deficits in the classification of dynamically presented facial emotional expressions. Using a community sample of adults with APD (n = 17) and non-APD controls (n = 16), speed and accuracy of facial emotional expression recognition was investigated in a task that morphs facial expressions from neutral to prototypical expressions (Multi-Morph Facial Affect Recognition Task; Blair, Colledge, Murray, & Mitchell, 2001). Results indicated that individuals with APD were significantly more likely than controls to make errors when classifying fully expressed fear. However, no differences were found between groups in the speed to correctly classify facial emotional expressions. The findings are some of the first to investigate facial emotional processing in a sample of individuals with APD and point to an underlying deficit in processing social cues that may be involved in the maintenance of APD. (PsycINFO Database Record (c) 2011 APA, all rights reserved)