Development of Implantable Flow-Through Left Ventricular Pressure Telemetric Transmitter for small Rodent Animals

Objective: Although 24-hour arterial blood pressure can be monitored in a free-moving animal using pressure telemetric transmitter mostly from Data Science International (DSI), accurate monitoring of 24-hour mouse left ventricular pressure (LVP) is not available because of its insufficient frequency response to a high frequency signal such as the maximum derivative of mouse LVP (LVdP/dtmax and LVdP/dtmin). The aim of the study was to develop a tiny implantable flow-through LVP telemetric transmitter for small rodent animals, which can be potentially adapted for human 24 hour BP and LVP accurate monitoring. Design and Method: The mouse LVP telemetric transmitter (Diameter: _12 mm, _0.4 g) was assembled by a pressure sensor, a passive RF telemetry chip, and to a 1.2F Polyurethane (PU) catheter tip. The device was developed in two configurations and compared with existing DSI system: (a) prototype-I: a new flow-through pressure sensor with wire link and (b) prototype-II: prototype-I plus a telemetry chip and its receiver. All the devices were applied in C57BL/6J mice. Data are mean_SEM. Results: A high frequency response (>100 Hz) PU heparin saline-filled catheter was inserted into mouse left ventricle via right carotid artery and implanted, LV systolic pressure (LVSP), LVdP/dtmax, and LVdP/dtmin were recorded on day2, 3, 4, 5, and 7 in conscious mice. The hemodynamic values were consistent and comparable (139_4 mmHg, 16634_319, - 12283_184 mmHg/s, n¼5) to one recorded by a validated Pebax03 catheter (138_2mmHg, 16045_443 and -12112_357 mmHg/s, n¼9). Similar LV hemodynamic values were obtained with Prototype-I. The same LVP waveforms were synchronically recorded by Notocord wire and Senimed wireless software through prototype-II in anesthetized mice. Conclusion: An implantable flow-through LVP transmitter (prototype-I) is generated for LVP accurate assessment in conscious mice. The prototype-II needs a further improvement on data transmission bandwidth and signal coupling distance to its receiver for accurate monitoring of LVP in a freemoving mouse.

Structural development of the Tso Morari ultra-high pressure nappe of the Ladakh Himalaya

A continental subduction-related and multistage exhumation process for the Tso Morari ultra-high pressure nappe is proposed. The model is constrained by published thermo-barometry and age data, combined with new geological and tectonic maps. Additionally, observations on the structural and metamorphic evolution of the Tso Morari area and the North Himalayan nappes are presented. The northern margin of the Indian continental crust was subducted to a depth of >90 km below Asia after continental collision some 55 Ma ago. The underthrusting was accompanied by the detachment and accretion of Late Proterozoic to Early Eocene sediments, creating the North Himalayan accretionary wedge, in front of the active Asian margin and the 103-50 Ma Ladakh arc batholith. The basic dikes in the Ordovician Tso Morari granite were transformed to eclogites with crystallization of coesite, some 53 Ma ago at a depth of >90 kin (>27 kbar) and temperatures of 500 to 600 degrees C. The detachment and extrusion of the low density Tso Morari nappe, composed of 70% of the Tso Morari granite and 30% of graywackes with some eclogitic dikes, occurred by ductile pure and simple shear deformation. It was pushed by buoyancy forces and by squeezing between the underthrusted Indian lithosphere and the Asian mantle wedge. The extruding Tso Morari nappe reached a depth of 35 km at the base of the North Himalayan accretionary wedge some 48 Ma ago. There the whole nappe stack recrystallized under amphibolite facies conditions of a Barrovian regional metamorphism with a metamorphic field gradient of 20 degrees C/km. An intense schistosity with a W-E oriented stretching lineation L, and top-to-the E shear criteria and crystallization of oriented sillimanite needles after kyanite, testify to the Tso Morari nappe extrusion and pressure drop. The whole nappe stack, comprising from the base to top the Tso Morari, Tetraogal, Karzok and Mata-Nyimaling-Tsarap nappes, was overprinted by new schistosities with a first N-directed and a second NE-directed stretching lineation L-2 and L-3 reaching the base of the North Himalayan accretionary wedge. They are characterized by top-to-the S and SW shear criteria. This structural overprint was related to an early N- and a younger NE-directed underthrusting of the Indian plate below Asia that was accompanied by anticlockwise rotation of India. The warping of the Tso Morari dome started already some 48 Ma ago with the formation of an extruding nappe at depth. The Tso Morari dome reached a depth of 15 km about 40 Ma ago in the eastern Kiagar La region and 30 Ma ago in the western Nuruchan region. The extrusion rate was of about 3 cm/yr between 53 and 48 Ma, followed by an uplift rate of 1.2 mm/yr between 48 and 30 Ma and of only 0.5 mm/yr after 30 Ma. Geomorphology observations show that the Tso Morari dome is still affected by faults, open regional dome, and basin and pull-apart structures, in a zone of active dextral transpression parallel to the Indus Suture zone.

Pulse wave analysis of aortic pressure: diastole should also be considered.

BACKGROUND: : The systolic augmentation index (sAix), calculated from the central aortic pulse wave (reconstructed from the noninvasive recording of the radial pulse with applanation tonometry), is widely used as a simple index of central arterial stiffness, but has the disadvantage of also being influenced by the timing of the reflected with respect to the forward pressure wave, as shown by its inverse dependence on heart rate (HR). During diastole, the central aortic pulse also contains reflected waves, but their relationship to arterial stiffness and HR has not been studied. METHODS: : In 48 men and 45 women, all healthy, with ages ranging from 19 to 70 years, we measured pulse wave velocity (PWV, patients supine), a standard evaluator of arterial stiffness, and carried out radial applanation tonometry (patients sitting and supine). The impact of reflected waves on the diastolic part of the aortic pressure waveform was quantified in the form of a diastolic augmentation index (dAix). RESULTS: : Across ages, sexes, and body position, there was an inverse relationship between the sAix and the dAix. When PWV and HR were added as covariates to a prediction model including age, sex and body position as main factors, the sAix was directly related to PWV (P < 0.0001) and inversely to HR (P < 0.0001). With the same analysis, the dAix was inversely related to PWV (P < 0.0001) and independent of HR (P = 0.52). CONCLUSION: : The dAix has the same degree of linkage to arterial stiffness as the more conventional sAix, while being immune to the confounding effect of HR. The quantification of diastolic aortic pressure augmentation by reflected waves could be a useful adjunct to pulse wave analysis.

Assessment of needs, health-related quality of life, and satisfaction with care in breast cancer patients to better target supportive care.

BACKGROUND: This study assessed whether breast cancer (BC) patients express similar levels of needs for equivalent severity of symptoms, functioning difficulties, or degrees of satisfaction with care aspects. BC patients who did (or not) report needs in spite of similar difficulties were identified among their sociodemographic or clinical characteristics. PATIENTS AND METHODS: Three hundred and eighty-four (73% response rate) BC patients recruited in ambulatory or surgery hospital services completed the European Organisation for Research and Treatment of Cancer Quality of Life questionnaire (EORTC QLQ)-C30 quality of life [health-related quality of life (HRQOL)], the EORTC IN-PATSAT32 (in-patient) or OUT-PATSAT35 (out-patient) satisfaction with care, and the supportive care needs survey short form 34-item (SCNS-SF34) measures. RESULTS: HRQOL or satisfaction with care scale scores explained 41%, 45%, 40% and 22% of variance in, respectively, psychological, physical/daily living needs, information/health system, and care/support needs (P < 0.001). BC patients' education level, having children, hospital service attendance, and anxiety/depression levels significantly predicted differences in psychological needs relative to corresponding difficulties (adjusted R(2) = 0.11). Medical history and anxiety/depression levels significantly predicted differences in information/health system needs relative to degrees of satisfaction with doctors, nurses, or radiotherapy technicians and general satisfaction (adjusted R(2) = 0.12). Unmet needs were most prevalent in the psychological domains across hospital services. CONCLUSIONS: Assessment of needs, HRQOL, and satisfaction with care highlights the subgroups of BC patients requiring better supportive care targeting.

Late Proterozoic thrust tectonics, high-pressure metamorphism and Uranium mineralization in the domes area, Lufilian arc, northwestern Zambia

The following main lithostratigraphic units have been distinguished in the Domes Area. The Kibaran basement complex composed of gneisses, migmatites with amphibolite bands and metagranites is exposed in dome structures; metamorphic features of Kibaran age have been almost completely obliterated by extensive Lufilian reactivation. The post-Kibaran cover sequence is subdivided into the Lower Roan Group consisting of well-preserved quartzites with high Mg content, talc-bearing, extremely foliated schists intercalated with pseudo-conglomerates of tectonic origin and the Upper Roan Group including dolomitic marbles with rare stromatolites, metapelites and a sequence of detrital metasediments, with local volcano-sedimentary components and interlayered banded ironstones. The sediments of the Lower Roan Group are interpreted as continental to lagoonal-evaporitic deposits partly converted into the talc-kyanite + garnet assemblage characteristic of ``white schists''. The dolomites and metapelites of the Upper Roan Group are attributed to a carbonate platform sequence progressively subsiding under terrigenous deposits, whilst the detrital metasediments and BIF may be interpreted as a basinal sequence, probably deposited on oceanic crust grading laterally into marbles. Metagabbros and metabasalts are considered as remnants of an ocean-floor-type crustal unit probably related to small basins. Alkaline stocks of Silurian age intruded the post-Kibaran cover. Significant ancestral tectonic discontinuities promoted the development of a nappe pile that underwent high-pressure metamorphism during the Lufilian orogeny and all lithostratigraphic units. Rb-Sr and K-Ar and U-Pb data indicate an age of 700 Ma for the highest grade metamorphism and 500 Ma for blocking of the K-Ar and Rb-Sr system in micas, corresponding to the time when the temperature dropped below 350-degrees-400-degrees-C and to an age of about 400 Ma for the emplacement of hypabyssal syenitic bodies. A first phase of crustal shortening by decoupling of basement and cover slices along shallow shear zones has been recognized. Fluid-rich tectonic slabs of cover sediments were thus able to transport fluids into the anhydrous metamorphic basement or mafic units. During the subsequent metamorphic re-equilibration stage of high pressure, pre-existing thrusts horizons were converted into recrystallized mylonites. Due to uplift, rocks were re-equilibrated into assemblages compatible with lower pressures and slightly lower temperatures. This stage occurs under a decompressional (nearly adiabatic) regime, with P(fluid) almost-equal-to P(lithostatic). It is accompanied by metasomatic development of minerals, activated by injection of hot fluids. New or reactivated shear zones and mylonitic belts were the preferred conduits of fluids. The most evident regional-scale effect of these processes is the intense metasomatic scapolitization of formerly plagioclase-rich lithologies. Uraninite mineralization can probably be assigned to the beginning of the decompressional stage. A third regional deformation phase characterized by open folds and local foliation is not accompanied by significant growth of new minerals. However, pitchblende mineralization can be ascribed to this phase as late-stage, short-range remobilization of previously existing deposits. Finally, shallow alkaline massifs were emplaced when the level of the Domes Area now exposed was already subjected to exchange with meteoric circuits, activated by residual geothermal gradients generally related to intrusions or rifting. Most of the superficial U-showings with U-oxidation products were probably generated during this relatively recent phase.

Factor structure of the SOCRATES questionnaire in hospitalized medical patients.

The Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES), a 19-item instrument developed to assess readiness to change alcohol use among individuals presenting for specialized alcohol treatment, has been used in various populations and settings. Its factor structure and concurrent validity has been described for specialized alcohol treatment settings and primary care. The purpose of this study was to determine the factor structure and concurrent validity of the SOCRATES among medical inpatients with unhealthy alcohol use not seeking help for specialized alcohol treatment. The subjects were 337 medical inpatients with unhealthy alcohol use, identified during their hospital stay. Most of them had alcohol dependence (76%). We performed an Alpha Factor Analysis (AFA) and Principal Component Analysis (PCA) of the 19 SOCRATES items, and forced 3 factors and 2 components, in order to replicate findings from Miller and Tonigan (Miller, W. R., & Tonigan, J. S., (1996). Assessing drinkers' motivations for change: The Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). Psychology of Addictive Behavior, 10, 81-89.) and Maisto et al. (Maisto, S. A., Conigliaro, J., McNeil, M., Kraemer, K., O'Connor, M., & Kelley, M. E., (1999). Factor structure of the SOCRATES in a sample of primary care patients. Addictive Behavior, 24(6), 879-892.). Our analysis supported the view that the 2 component solution proposed by Maisto et al. (Maisto, S.A., Conigliaro, J., McNeil, M., Kraemer, K., O'Connor, M., & Kelley, M.E., (1999). Factor structure of the SOCRATES in a sample of primary care patients. Addictive Behavior, 24(6), 879-892.) is more appropriate for our data than the 3 factor solution proposed by Miller and Tonigan (Miller, W. R., & Tonigan, J. S., (1996). Assessing drinkers' motivations for change: The Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES). Psychology of Addictive Behavior, 10, 81-89.). The first component measured Perception of Problems and was more strongly correlated with severity of alcohol-related consequences, presence of alcohol dependence, and alcohol consumption levels (average number of drinks per day and total number of binge drinking days over the past 30 days) compared to the second component measuring Taking Action. Our findings support the view that the SOCRATES is comprised of two important readiness constructs in general medical patients identified by screening.

Current trends in illegal drug use and drug related health problems in Switzerland.

As part of the evaluation of the Confederation's measures to reduce drug related problems, a review of available data on drug use and drug related problems in Switzerland has been conducted. Source of data included: population surveys (adults and teenagers), surveys among drug users, health statistics (drug related and AIDS related deaths, HIV case reporting, drug treatments) police statistics (denunciations for consumption). The aims of reducing the number of dependent hard drug users have been achieved where heroin is concerned. In particular, there seems to have been a decrease in the number of people becoming addicted to this substance. For all other illegal substances, especially cannabis, the trend is towards an increased use, as in many European countries. As regards dependent drug users, especially injecting drug users, progress has been made in the area of harm reduction and treatment coverage. This epidemiological assessment can be used in the discussions currently engaged about the revision of the Law governing narcotics and will be a baseline for future follow up of the situation.

Incidents and complications of totally implanted vascular access devices in children: a prospective study.

BACKGROUND: Totally implanted vascular access devices are frequently used in children for repeated blood samples or intravenous treatments. This prospective study aims at identifying the risk factors associated with infections, obstructions and surgical complications of these devices in pediatric patients. METHODS: From January 2006 to January 2008, all children older than one year of age with a diagnosis of solid or blood cell malignancy were included in the study. Insertion was performed by the surgeon according to a standardized protocol after landmark-guided puncture of the subclavian or internal jugular vein by a senior anesthesiologist. Dressing and post-operative care were standardized. Every manipulation was prospectively recorded by specialized dedicated nurses, and all patients were screened for complications one month post-surgery. RESULTS: 45 consecutive patients 1 to 16 years old were enrolled in the study. Mean age at the time of procedure was 8.5 years (range 1.3-15.6; SD +/- 4.88). There were 12 peroperative adverse events in 45 procedures (27%), detailed as follows: 3 pneumothoraces (7%), 3 hematomas (7%), 6 arterial punctures (13%). Among these events, intervention was necessary for two pneumothorax and one arterial puncture. There was no air embolism. At one month, we recorded 5 post-operative complications (11%): 2 thrombotic obstructions, one unsightly scar, and one scapular pain of unknown etiology. One patient needed repositioning of the catheter. There was no catheter-related infection. CONCLUSION: Prospective recording of TIVA insertion in children reveals a significant number of early incidents and complications, mainly associated with the percutaneous puncture technique. We found no infection in this series. Results of a longer follow-up in the same population are pending.

Internet use by patients with psychiatric disorders in search for general and medical informations

BACKGROUND: Internet is commonly used by the general population, notably for health information-seeking. There has been little research into its use by patients treated for a psychiatric disorder. AIM: To evaluate the use of internet by patients with psychiatric disorders in searching for general and medical information. METHODS: In 2007, 319 patients followed in a university hospital psychiatric out-patient clinic, completed a 28-items self-administered questionnaire. RESULTS: Two hundred patients surveyed were internet users. Most of them (68.5%) used internet in order to find health-related information. Only a small part of the patients knew and used criteria reflecting the quality of contents of the websites consulted. Knowledge of English and private Internet access were the factors significantly associated with the search of information on health on Internet. CONCLUSIONS: Internet is currently used by patients treated for psychiatric disorders, especially for medical seeking information.

Transcatheter aortic valve implantation (TAVI): state of the art techniques and future perspectives.

Transcatheter aortic valve therapies are the newest established techniques for the treatment of high risk patients affected by severe symptomatic aortic valve stenosis. The transapical approach requires a left anterolateral mini-thoracotomy, whereas the transfemoral method requires an adequate peripheral vascular access and can be performed fully percutaneously. Alternatively, the trans-subclavian access has been recently proposed as a third promising approach. Depending on the technique, the fine stent-valve positioning can be performed with or without contrast injections. The transapical echo-guided stent-valve implantation without angiography (the Lausanne technique) relies entirely on transoesophageal echocardiogramme imaging for the fine stent-valve positioning and it has been proved that this technique prevents the onset of postoperative contrast-related acute kidney failure. Recent published reports have shown good hospital outcomes and short-term results after transcatheter aortic valve implantation, but there are no proven advantages in using the transfemoral or the transapical technique. In particular, the transapical series have a higher mean logistic Euroscore of 27-35%, a procedural success rate above 95% and a mean 30-day mortality between 7.5 and 17.5%, whereas the transfemoral results show a lower logistic Euroscore of 23-25.5%, a procedural success rate above 90% and a 30-day mortality of 7-10.8%. Nevertheless, further clinical trials and long-term results are mandatory to confirm this positive trend. Future perspectives in transcatheter aortic valve therapies would be the development of intravascular devices for the ablation of the diseased valve leaflets and the launch of new stent-valves with improved haemodynamic, different sizes and smaller delivery systems.

Poly-N-acetyl glucosamine fibers are synergistic with vacuum-assisted closure in augmenting the healing response of diabetic mice.

BACKGROUND: Vacuum-assisted closure (VAC) has become the preferred modality to treat many complex wounds but could be further improved by methods that minimize bleeding and facilitate wound epithelialization. Short fiber poly-N-acetyl glucosamine nanofibers (sNAG) are effective hemostatic agents that activate platelets and facilitate wound epithelialization. We hypothesized that sNAG used in combination with the VAC device could be synergistic in promoting wound healing while minimizing the risk of bleeding. METHODS: Membranes consisting entirely of sNAG nanofibers were applied immediately to dorsal excisional wounds of db/db mice followed by application of the VAC device. Wound healing kinetics, angiogenesis, and wound-related growth factor expression were measured. RESULTS: The application of sNAG membranes to wounds 24 hours before application of the VAC device was associated with a significant activation of wounds (expression of PDGF, TGFβ, EGF), superior granulation tissue formation rich in Collagen I as well as superior wound epithelialization (8.6% ± 0.3% vs. 1.8% ± 1.1% of initial wound size) and wound contraction. CONCLUSIONS: The application of sNAG fiber-containing membranes before the application of the polyurethane foam interface of VAC devices leads to superior healing in db/db mice and represents a promising wound healing adjunct that can also reduce the risk of bleeding complications.

La prothèse de St Jude medical chez les patients âges de plus de 65 ans [St Jude's Medical prosthesis in patients over 65].

Between September 1979 and December 1982, 56 St Jude Medical valvular prostheses were implanted in 54 patients over 65 years of age. Surgery consisted in simple aortic valve replacement (35 cases), simple mitral valve replacement (12 cases), double aortic and mitral valve replacement (2 cases), valve replacement and coronary artery bypass surgery (3 cases), aortic valve replacement and replacement of the ascending aorta (1 case) and mitral valve replacement and tricuspid annuloplasty (1 case). The operative mortality (within 30 days of surgery) was 3.5% (2 cases). Patients were assessed by clinical examination, ECG, chest X-ray, echocardiogram and laboratory investigations on average 19 months after surgery. There were 3 late deaths (1 endocarditis, 1 cardiac failure and 1 subdural haematoma). No cases of significant haemolysis were observed. There were no cases of thrombosis of the valve or any deaths directly related to the valve. Four patients had cerebral embolism (4.9% per patient/year). None were fatal and only 1 patient had sequellae. Clinical improvement was very significant; 96% of the patients are now in the NYHA Classes I and II whilst 80% were in Class III or IV before surgery. The cardiothoracic ratio decreased significantly from 0.56 to 0.51 (p less than 0.01). The authors conclude that elderly patients may derive great benefits from valvular cardiac surgery and that age in itself is not a contraindication to this type of surgery. The St Jude Medical prosthesis is an excellent prosthesis but thromboembolism remains a major problem as with other mechanical prostheses. Anticoagulation for life is essential.

Centralised versus Decentralised Management of Patients's Medical Records

For more than 20 years, many countries have been trying to set up a standardised medical record at the regional or at the national level. Most of them have not reached this goal, essentially due to two main difficulties related to patient identification and medical records standardisation. Moreover, the issues raised by the centralisation of all gathered medical data have to be tackled particularly in terms of security and privacy. We discuss here the interest of a noncentralised management of medical records which would require a specific procedure that gives to the patient access to his/her distributed medical data, wherever he/she is located.

Sports-related chronic repetitive head trauma as a cause of pituitary dysfunction.

Traumatic brain injury (TBI) is recognized as a cause of hypopituitarism even after mild TBI. Although over the past decade, a growing body of research has detailed neuroendocrine changes induced by TBI, the mechanisms and risk factors responsible for this pituitary dysfunction are still unclear. Around the world, sports-especially combative sports-are very popular. However, sports are not generally considered as a cause of TBI in most epidemiological studies, and the link between sports-related head trauma and hypopituitarism has not been investigated until recently. Thus, there is a paucity of data regarding this important concern. Because of the large number of young sports participants with near-normal life expectancy, the implications of undiagnosed or untreated postconcussion pituitary dysfunction can be dramatic. Understanding the pathophysiological mechanisms and risk factors of hypopituitarism caused by sports injuries is thus an important issue that concerns both medical staff and sponsors of sports. The aim of this paper was to summarize the best evidence for understanding the pathophysiological mechanisms and to discuss the current data and recommendations on sports-related head trauma as a cause of hypopituitarism.