[Psychosomatical approach to Hyperemesis gravidarum]. / Approche psychosomatique des vomissements incoercibles du premier trimestre.

Vomiting of pregnancy is a physiological symptom of the first trimester and is a frequent reason for consultation in emergency as well as hospitalization in the severe forms (Hyperemesis gravidarum). Though strong the aversion usually developed against the hospitalized patients for H. gravidarum may be, it is important to understand the distress of these women with a symptom difficult to endure, which often reflects a psychical conflict with respect to their pregnancy. The gynecologist must be the somatic doctor who deals with the symptom and its sometimes disastrous clinical consequences, whereas the psychologist or the psychiatrist plays a fundamental role in this pathology. Indeed, he will lead the patient to work on how she feels her pregnancy, to give it a place in her personal history and to understand her contradictory feelings with regard to this pregnancy.

Multilayer conformal applicator for microwave heating and brachytherapy treatment of superficial tissue disease.

PURPOSE: The purpose of this study was to construct and perform preliminary functionality evaluations of a multilayer conformal applicator with provisions for thermal monitoring, tight conformity and simultaneous microwave heating and brachytherapy treatment of large-area contoured surfaces. MATERIALS AND METHODS: The multilayer conformal applicator consists of thermal monitoring catheters for fibre-optic monitoring of skin temperatures, a waterbolus, a PCB microwave antenna array, a dielectric spacer for brachytherapy considerations, brachytherapy catheters for delivering HDR radiation and an inflatable air bladder for improving conformity to contoured surfaces. The applicator also includes an elastic attachment structure to hold the applicator securely in place on the patient. The conformity of the applicator to irregular surfaces was evaluated through CT imaging of the applicator fitted onto a life-sized human torso phantom. The fluid flow dynamics of the waterbolus, which impact the effectiveness of temperature control, were evaluated with thermometry during a 19 degrees C step change temperature of the circulating water. RESULTS: CT imaging showed improved conformity to the torso phantom surface following the application of gentle inward pressure from inflating the outer air bladder. Only a small number of 1-5 mm sized air gaps separated the conformal applicator and tissue surface. Thermometry testing of the bolus fluid flow dynamics demonstrated temperature uniformity within +/-0.82 degrees C across a 19 x 34 x 0.6 cm area bolus and +/-0.85 degrees C across a large 42 x 32 x 0.6 cm area bolus. CONCLUSION: CT scans of the applicator confirmed that the applicator conforms well to complex body contours and should maintain good conformity and positional stability even when worn on a mobile patient. Thermometry testing of two different waterbolus geometries demonstrated that uniform circulation and temperature control can be maintained throughout large, complex bolus shapes.

Evaluation of a dual-arm Archimedean spiral array for microwave hyperthermia.

PURPOSE: This effort describes a third-party performance evaluation of a novel, commercial, dual-armed Archimedean spiral array hyperthermia applicator. The applicator is analysed for its ability to couple efficiently into muscle equivalent phantom loads, operate over a broad bandwidth to help accommodate variable tissue properties and generate predictable and repeatable SAR contours that are adaptable to clinically probable disease shapes. MATERIALS AND METHODS: Characterization of the applicator includes E-field and return-loss measurements in liquid muscle tissue-equivalent phantom, as well as comparison of 'treatment-planning' simulations of several possible array SAR patterns with measured SAR from non-coherently driven spiral array antennae. RESULTS: The applicator demonstrates a reasonably low return loss over a large bandwidth and the ability to generate a very uniform heating pattern. Ability to adjust SAR contours spatially to fit specific shapes is also demonstrated. CONCLUSIONS: This device should prove a welcome addition to a currently limited set of superficial heating applicators to provide controllable heating of superficial tissue disease.

Combination applicator for simultaneous heat and radiation.

We present the development of operator and patient friendly conformal applicators that can deliver moderate temperature hyperthermia simultaneously with radiation in superficial tissue overlying contoured anatomy. This applicator combines the uniform heating capabilities of large area conformal microwave array (CMA) flexible printed circuit board applicators with a patient interface (coupling bolus) that facilitates positioning of brachytherapy sources at a fixed distance (e.g. 1.5 cm) from the skin. A customized inverse treatment planning program (IPSA) was used to optimize spacing of a parallel array of source catheters and separation distance from skin, and to characterize the effects of bolus thickness and conformal array curvature on radiation dose uniformity. Performance of a 15 cmx15 cm combination applicator was evaluated in flat and contoured homogenous muscle tissue models. Results demonstrate effective heating and radiation distributions to 1-1.5 cm depth and out to the periphery of the array. This applicator should prove useful for treatment of diffuse chestwall disease located over contoured anatomy that is difficult to treat with external beam radiation. By applying heat and radiation simultaneously for maximum synergism of modalities, this device should expand the number of patients that can benefit from effective thermoradiotherapy for superficial disease.

Construction of a conformal water bolus vest applicator for hyperthermia treatment of superficial skin cancer.

Large area chestwall recurrence of breast carcinoma can be treated with moderate temperature hyperthermia in combination with radiation or chemotherapy. For diffuse chestwall disease, hyperthermia is best delivered with a conformal microwave array (CMA) applicator using a temperature-controlled water bolus designed specifically to fit complex contours and maintain contact with the tissue surface to prevent air gaps which distort the microwave power deposition pattern. In order to maintain the desired temperature range of 41-45 degrees C during local hyperthermia treatments, it is necessary to have an effective fluid flow system to serve as a buffer and prevent overheating of skin, which can lead to small blisters or, in rare cases, deeper burns. The fluid flow dynamics of a vest shaped open water bag design is evaluated with thermometry during a step temperature change of circulating water. The data confirm the feasibility of uniform circulation and temperature control throughout complex bolus shapes. This water bolus design should improve temperature uniformity of current treatments for superficial tissue disease.

Phantom and animal tissues for modelling the electrical properties of human liver.

The dielectric properties of human liver were characterized over the frequency range of 0.3-3 GHz for freshly excised tissue samples of primary hepatocellular carcinoma, metastatic colorectal carcinoma, and normal liver tissues resected from the tumour margin. On average, the dielectric constant (epsilon(r)) of freshly excised human liver tumour was 12% higher than that of surrounding normal liver, and the electrical conductivity (sigma) of tumour was 24% higher. In order to establish suitable tissue models for human liver, the electrical properties were compared to measurements of homogenous phantom mixtures, in vitro bovine liver, and in vivo canine and porcine liver tissues. The data demonstrate that there are several animal tissues that can be used to model the average dielectric properties of human liver reasonably accurately, and use of the most readily available bovine liver appears well-justified, even when stored for up to 10 days in a refrigerator. Additionally, the dielectric properties of in vitro liver remained stable over a large temperature range, with sigma rising only 1.1%/ degrees C in porcine liver (15-37 degrees C) and 2.0%/ degrees C in bovine liver (10-90 degrees C), and epsilon(r) decreasing < or =0.2%/ degrees C in both tissues. This effort identifies homogeneous solid and liquid phantom models and several heterogeneous in vitro tissues that adequately model the dielectric properties of human liver tumours for use in quantitative studies of microwave power deposition in liver.

SAR pattern perturbations from resonance effects in water bolus layers used with superficial microwave hyperthermia applicators.

This study examines the effect of various thickness water bolus coupling layers on the SAR (Specific Absorption Rate) patterns from Dual Concentric Conductor (DCC) based Conformal Microwave Array (CMA) superficial hyperthermia applicators. Previous theory has suggested that water bolus coupling layers can be considered as a dielectric resonator; therefore, it is possible for the impinging electric field to stimulate volume oscillations and surface wave oscillations inside the water bolus. These spurious oscillations will destructively or constructively interact with the impinging electric field to cause a perturbation of the applicator SAR pattern. An experiment was designed which consisted of mapping the electric field produced by a four element DCC CMA applicator in liquid muscle phantom at depths of 5 and 10mm in front of four different thickness water boli; 0 (no bolus) 4, 9 and 13mm. Using the Finite Difference Time Domain (FDTD) method, SAR distributions were calculated for similar test cases. It was found that for water bolus thicknesses of 9mm or greater, there is a marked perturbation of both experimental and theoretical SAR distributions. It is believed that this perturbation is experimental confirmation of the volume and surface wave oscillation theory described by previous investigators.

Dual-mode antenna design for microwave heating and noninvasive thermometry of superficial tissue disease.

Hyperthermia therapy of superficial skin disease has proven clinically useful, but current heating equipment is somewhat clumsy and technically inadequate for many patients. The present effort describes a dual-purpose, conformal microwave applicator that is fabricated from thin, flexible, multilayer printed circuit board (PCB) material to facilitate heating of surface areas overlaying contoured anatomy. Preliminary studies document the feasibility of combining Archimedean spiral microstrip antennas, located concentrically within the central region of square dual concentric conductor (DCC) annular slot antennas. The motivation is to achieve homogeneous tissue heating simultaneously with noninvasive thermometry by radiometric sensing of blackbody radiation from the target tissue under the applicator. Results demonstrate that the two antennas have complimentary regions of influence. The DCC ring antenna structure produces a peripherally enhanced power deposition pattern with peaks in the outer corners of the aperture and a broad minimum around 50% of maximum centrally. In contrast, the Archimedean spiral radiates (or receives) energy predominantly along the boresight axis of the spiral, thus confining the region of influence to tissue located within the central broad minimum of the DCC pattern. Analysis of the temperature-dependent radiometer signal (brightness temperature) showed linear correlation of radiometer output with test load temperature using either the spiral or DCC structure as the receive antenna. The radiometric performance of the broadband Archimedean antenna was superior compared to the DCC, providing improved temperature resolution (0.1 degree C-0.2 degree C) and signal sensitivity (0.3 degree C-0.8 degree C/degree C) at all four 500 MHz integration bandwidths tested within the frequency range from 1.2 to 3.0 GHz.

Structural and functional characteristics of rhenium clusters derived from redox chemistry of the triangular [ReIII3(mu-Cl)3] core unit.

The present study investigates structural and functional aspects of the redox chemistry of rhenium(III) chloride [Re3Cl9] (1) in aqueous and organic solvents, with emphasis on the dioxygen-activating capabilities of reduced rhenium clusters bearing the Re3(8+) core. Dissolution of 1 in HCl (6 M) generates [Re3(mu-Cl)3Cl9]3- (2a), which can be isolated as the tetraphenylphosphonium salt (2b). Anaerobic one-electron reduction of 1 by Hg in HCl (6-12 M) produces [(C6H5)4P]2[Re3(mu-Cl)3Cl7(H2O)2].H2O (3), the structure of which features a planar [Re3(mu-Cl)3Cl3] framework (Re3(8+) core), involving two water ligands that occupy out-of-plane positions in a trans arrangement. Compound 3 dissociates in the presence of CO, yielding [(C6H5)4P]2[ReIII2Cl8] (4) and an unidentified red carbonyl species. In situ oxidation (O2) of the reduced Re3(8+)-containing cluster in HCl (6 M) produces quantitatively 2a, whereas oxidation of 3 in organic media results in the formation of [(C6H5)4P]4[(Re3(mu-Cl)3Cl7(mu-OH))2].2CH2Cl2 (5). The structure of 5 reveals that two oxygen ligands (hydroxo units) bridge asymmetrically two Re3(9+) triangular clusters. The origin of these hydroxo units derives from the aquo ligands, rather than O2, as shown by 18O2 labeling studies. The hydroxo bridges of 5 can be replaced by chlorides upon treatment with Me3SiCl to afford the analogous [(C6H5)4P]4[(Re3(mu-Cl)3Cl7(mu-Cl))2].10CH2Cl2 (6). The reaction of 5 with Hg in HCl (6 M)/tetrahydrofuran regenerates compound 3. Complexes 1-3 exhibit nitrile hydratase type activity, inducing hydrolysis of CH3CN to acetamide. The reaction of 3 with CH3CN yields [(C6H5)4P]2[Re3(mu-Cl)3Cl6.5(CH3CN)1.5(CH3C(O)NH)0.5] (7), the structure of which is composed of [Re3(mu-Cl)3Cl7(CH3CN)2]2- (7a) and [Re3(mu-Cl)3Cl6(CH3CN)(CH3C(O)NH)]2- (7b) (Re3(8+) cores) as a disordered mixture (1:1). Oxidation of 7 with O2 in CH3CN affords [(C6H5)4P]2[Re3(mu-Cl)3Cl7(CH3C(O)NH)].CH3CN (8) and small amounts of [(C6H5)4P][ReO4] (9). Compound 8 is also independently isolated from the reaction of 2b with wet CH3CN, or by dissolving 5 in CH3CN. In MeOH, 5 dissociates to afford [(C6H5)4P]2[Re3(mu-Cl)3Cl8(MeOH)].MeOH (10).

Operative treatment of hip fractures in patients with renal failure.

The conditions of a hip fracture and renal failure cause particularly high mortality. Eight patients (average age, 63 years) who had operative treatment for nine hip fractures were studied retrospectively. Three had intertrochanteric fractures fixed with sliding compression screws, and five had femoral neck fractures (bilateral in one patient): two nondisplaced femoral neck fractures were fixed with percutaneous screws, and four displaced femoral neck fractures were treated with arthroplasties in three and percutaneous screws in one. Operative treatment was done when the patient was in medically stable condition (average, 8 days). Full weightbearing was allowed on the injured limb after surgery. Early morbidity analysis showed no wound infections, thromboembolic events, or hemorrhagic complications. The first year mortality was three (38%). Late morbidity included one nonunion and one sliding screw penetration. Total mortality at 6 years was seven (88%) patients, with an average postoperative survival time of 28 months. Preoperative ambulation was preserved in five of seven (71%) patients. One the basis of this study, it appears that a team approach to operative management including nephrologist and surgeon helps to reduce short term complications and mortality and allows such patients to be mobilized and regain ambulation.

Lens anatomical principles and their technical implications in cataract surgery. Part II: The lens nucleus.

Preservation of the intact ("true") capsular bag, with no tears to the periphery, is essential to assure permanent in-the-bag fixation of the intraocular lens. Removal of a large nucleus using the open-system planned extracapsular cataract extraction (ECCE) technique is often associated with tearing of the capsulectomy or serious complications such as zonular rupture, vitreous loss, unintended intracapsular cataract extraction, or posterior lens prolapse. A closed-system planned ECCE technique which allows a safe removal of the lens while maintaining the integrity of the capsular bag is presented. Hydrodissection of the lens nucleus to an epinucleus and a central hard nucleus allows hydroextraction of the small hard core while pushing the posterior capsule backward. The positive pressure in the anterior chamber, provided by the anterior chamber maintainer, keeps the position of the lens steady in its natural location, and minimizes the stress on the zonular apparatus during nucleus delivery. The remaining epinucleus can be either hydroexpressed or aspirated. Fracturing the central core, when possible, enables removal of the lens material through a small limbal incision. Viscoelastic material can be combined with a low-flow, anterior chamber maintainer in a closed-system and provides a useful surgical tool.

Root hypoxia reduces leaf growth : role of factors in the transpiration stream.

This study examined the potential role of restricted phloem export, or import of substances from the roots in the leaf growth response to root hypoxia. In addition, the effects of root hypoxia on abscisic acid (ABA) and zeatin riboside (ZR) levels were measured and their effects on in vitro growth determined. Imposition of root hypoxia in the dark when transpirational water flux was minimal delayed the reduction in leaf growth until the following light period. Restriction of phloem transport by stem girdling did not eliminate the hypoxia-induced reduction in leaf growth. In vitro growth of leaf discs was inhibited in the presence of xylem sap collected from hypoxic roots, and also by millimolar ABA. Disc growth was promoted by sap from aerated roots and by 0.1 micromolar ZR. The flux of both ABA and ZR was reduced in xylem sap from hypoxic roots. Leaf ABA transiently increased twofold after 24 hours of hypoxia exposure but there were no changes in leaf cytokinin levels.