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1.
Nurse Educ Today ; 106: 105042, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34274748

ABSTRACT

BACKGROUND: The growing prevalence of chronic illnesses requires nurses to support self-management and help patients integrate the chronic illness into their life. To our knowledge there are currently no training programs that combine the necessary components to adequately enhance nurses' competencies in self-management support. OBJECTIVE: The systematic development and validation of a need-supportive training in self-management support for nurses. DESIGN: A three-phased study, according to van Meijel et al. (2004), with collection of building blocks, design, and validation of the need-supportive character of the training. SETTING AND PARTICIPANTS: Eight training groups with 30 nurses, 34 nursing students and nine social healthcare workers from different nursing colleges in Flanders, Belgium. METHODS: In phase one a literature review, current practice analysis, and problem and needs analysis were performed. In phase two, the INTENSS training intervention was developed, framed within the Self-Determination Theory and the 5A's-Model. The training consisted of a basic training module and a video-interaction guidance module. The intervention was subsequently tested in eight training groups (N = 73). Participants provided feedback during focus group discussions. The intervention was cyclically adapted to trainees' experiences and suggestions. In phase three, we evaluated the need-supportive character of the training intervention. RESULTS: Phase one indicated the need for training, since nurses' application of self-management support was limited and practiced from a narrow medical point of view. In phase two we developed a theory-driven and multifaceted training, building on attitude, knowledge, skills and reflection in the training. The training was framed within the Self-Determination Theory both at the didactical level as well as on content and format. Overall, participants appreciated the building blocks of the training as supporting their basic needs for autonomy, relatedness and competence. CONCLUSIONS: INTENSS, a multifaceted need-supportive training in self-management support was developed, successfully taking into account participants' needs.


Subject(s)
Nurses , Self-Management , Students, Nursing , Attitude of Health Personnel , Chronic Disease , Humans
2.
Ann Oncol ; 29(1): 71-83, 2018 01 01.
Article in English | MEDLINE | ID: mdl-29069302

ABSTRACT

Checkpoint receptor blockers, known to act by blocking the pathways that inhibit immune cell activation and stimulate immune responses against tumor cells, have been immensely successful in the treatment of cancer. Among several checkpoint receptors of immune cells, cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), programmed cell death protein-1 (PD-1), T-cell immunoglobulin and ITIM domain (TIGIT), T-cell immunoglobulin-3 (TIM-3) and lymphocyte activation gene 3 (LAG-3) are the most commonly targeted checkpoints for cancer immunotherapy. Six drugs including one CTLA-4 blocker (ipilimumab), two PD-1 blockers (nivolumab and pembrolizumab) and three PD-L1 blockers (atezolizumab, avelumab and durvalumab) are approved for the treatment of different types of cancers including both solid tumors such as melanoma, lung cancer, head and neck cancer, bladder cancer and Merkel cell cancer as well as hematological tumors such as classic Hodgkin's lymphoma. The main problem with checkpoint blockers is that only a fraction of patients respond to the therapy. Insufficient immune activation is considered as one of the main reason for low response rates and combination of checkpoint blockers has been proposed to increase the response rates. The combination of checkpoint blockers was successful in melanoma but had significant adverse events. A combination that is selected based on the mechanistic differences between checkpoints and the differences in expression of checkpoints and their ligands in the tumor microenvironment could have a synergistic effect in a given cancer subtype and also have a manageable safety profile. This review aims to help in design of optimal checkpoint blocker combinations by discussing the mechanistic details and outlining the subtle differences between major checkpoints targeted for cancer immunotherapy.


Subject(s)
Antineoplastic Agents, Immunological/therapeutic use , Immunotherapy/methods , Neoplasms/immunology , Neoplasms/therapy , Animals , Humans
3.
Faraday Discuss ; 191: 373-389, 2016 10 06.
Article in English | MEDLINE | ID: mdl-27460036

ABSTRACT

We report on the fabrication of oriented anisotropic metal nanoparticle thin films made by Grazing Incidence Spraying (GIS) and on the anisotropic plasmonic properties of the resulting thin films. Gold nanorods of two different aspect ratios and silver nanowires were self-assembled as a uniaxially aligned monolayer with the GIS approach. In particular, we examine the influence of the nanowire/nanorod length and diameter on the degree of ordering determined by electron microscopy pictures. Furthermore, we show that the anisotropy of the optical properties (probed by polarized UV-visible-near infrared spectroscopy) strongly depend on the quality of alignment. The prepared monolayer thin films have an orientation order parameter of up to 0.83 for silver nanowires, which is reflected in an optical anisotropy of 0.57 in the UV-visible and 0.76 in the near infrared through the selective excitation of transverse and longitudinal surface plasmon resonance modes. The electronic transport in oriented silver nanowire monolayers is also shown to be highly directional, with the sheet resistance varying over almost an order of magnitude depending on the transport direction. Such anisotropic conductive plasmonic thin films may find applications in various fields like biochemical sensing, energy transport and harvesting or optoelectronic devices.

4.
J Viral Hepat ; 18(10): e516-22, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21914071

ABSTRACT

Liver steatosis is a main histopathological feature of Hepatitis C (HCV) infection because of genotype 3. Steatosis and/or mechanisms underlying steatogenesis can contribute to hepatocarcinogenesis. The aim of this retrospective study was to assess the impact of infection with HCV genotype 3 on hepatocellular carcinoma (HCC) occurrence in patients with ongoing HCV cirrhosis. Three hundred and fifty-three consecutive patients (193 men, mean age 58 ± 13 years), with histologically proven HCV cirrhosis and persistent viral replication prospectively followed and screened for HCC between 1994 and 2007. Log-rank test and Cox model were used to compare the actuarial incidence of HCC between genotype subgroups. The patients infected with a genotype 3 (n = 25) as compared with those infected with other genotypes (n = 328) had a lower prothrombin activity [78 (interquartile range 60-85) vs 84 (71-195) %, P = 0.03] and higher rate of alcohol abuse (48%vs 29%, P = 0.046). During a median follow-up of 5.54 years [2.9-8.6], 11/25 patients (44%) and 87/328 patients (26%) with a genotype 3 and non-3 genotype, respectively, develop a HCC. HCC incidences were significantly different among the genotype subgroups (P = 0.001). The 5-year occurrence rate of HCC was 34% (95% CI, 1.3-6.3) and 17% (95% CI, 5.7-9.2) in genotype 3 and non-3 genotype groups, respectively (P = 0.002). In multivariate analysis, infection with a genotype 3 was independently associated with an increased risk of HCC occurrence [hazard ratio 3.54 (95% CI, 1.84-6.81), P = 0.0002], even after adjustment for prothrombin activity and alcohol abuse [3.58 (1.80-7.13); P = 0.003]. For patients with HCV cirrhosis and ongoing infection, infection with genotype 3 is independently associated with an increased risk of HCC development.


Subject(s)
Carcinoma, Hepatocellular/epidemiology , Hepacivirus/classification , Hepacivirus/pathogenicity , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/virology , Liver Cirrhosis/complications , Liver Cirrhosis/virology , Aged , Fatty Liver/complications , Fatty Liver/pathology , Fatty Liver/virology , Female , Genotype , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis C, Chronic/pathology , Humans , Incidence , Liver Cirrhosis/pathology , Male , Middle Aged , Retrospective Studies
5.
Rev Med Liege ; 64(7-8): 414-7, 2009.
Article in French | MEDLINE | ID: mdl-19777924

ABSTRACT

Solitary lipoma is the most frequent soft tissue tumor, often appearing between 40 and 60 years of age. It is described as "giant" beyond 1 kg of weight and 10 cm of diameter. Its volume is the source of a good many problems in social life (camouflage, difficulties to dress) and causes multiple health problems such as pain, difficulties to sleep, compressions of nerves or vital structures, infections, etc. The diagnosis is primarily clinical. However, it is necessary to systematically exclude a malignant process. Surgical biopsy is recommended if the diagnosis cannot be asserted by the clinic or an imagery. The therapeutic attitude is abstention in case of small volume without functional impairment. Otherwise, total surgical excision is indicated with pathological analysis. We describe the clinical history of a patient suffering from a giant dorsal lipoma.


Subject(s)
Back/pathology , Back/surgery , Lipoma/pathology , Adult , Biopsy , Diagnosis, Differential , Female , Humans , Lipoma/complications , Lipoma/surgery , Quality of Life , Scapula/pathology , Treatment Outcome
6.
Aliment Pharmacol Ther ; 28(9): 1102-10, 2008 Nov 01.
Article in English | MEDLINE | ID: mdl-18691352

ABSTRACT

BACKGROUND: Hepatic venous pressure gradient (HVPG) is the gold standard for assessing the presence and the severity of portal hypertension (PHT). Liver stiffness measurement (LSM) is a non-invasive method for liver fibrosis assessment. AIMS: To assess the relationship between LSM and HVPG in patients with compensated cirrhosis related to hepatitis C virus (HCV) or alcohol and to define the performance and the best cut-off of LSM for the diagnosis of PHT in these patients. METHODS: Between January 2004 and September 2006, we studied all the consecutive patients with compensated HCV or alcohol-related-cirrhosis referred for transjugular liver biopsy with HVPG measurement and LSM performed the same day. RESULTS: Ninety-two patients were eligible, 44 had HCV related-cirrhosis and 48 alcoholic cirrhosis. LSM was positively correlated to HVPG in both groups. The area under the receiver operating characteristic curve for the diagnosis of significant PHT was 0.76 +/- 0.07 in HCV patients (best cut-off at 20.5 kPa) and 0.94 +/- 0.03 (best cut-off at 34.9 kPa) in alcoholic patients. CONCLUSIONS: Liver stiffness measurement and HVPG were significantly correlated in patients with compensated cirrhosis because of HCV infection or alcohol. LSM could predict significant PHT in both these groups of patients with a higher cut-off and a better performance in alcoholic patients.


Subject(s)
Hepatic Veins/physiopathology , Hepatitis C, Chronic/physiopathology , Hypertension, Portal/diagnosis , Liver Cirrhosis, Alcoholic/physiopathology , Portal Vein/physiopathology , Adult , Aged , Elasticity , Elasticity Imaging Techniques/methods , Female , Hepatitis C, Chronic/complications , Humans , Hypertension, Portal/physiopathology , Liver Cirrhosis, Alcoholic/complications , Male , Middle Aged , Predictive Value of Tests , Venous Pressure
7.
Acta Chir Belg ; 108(3): 298-303, 2008.
Article in English | MEDLINE | ID: mdl-18710102

ABSTRACT

As the incidence of breast cancer increases, breast reconstruction is more and more often proposed and its indications are viewed in terms of quality of life. In the past, delayed reconstruction was the rule. Progress in reconstructive techniques currently allows performing immediate reconstruction in selected cases, even when the operative field has to be irradiated. These new techniques generally improve the result of breast reconstruction. Moreover, expansion of screening techniques allows detection of small tumors for which a conservative excision is sufficient. Nevertheless, this kind of less aggressive surgery may require a reconstructive procedure in order to maximise the aesthetic result.


Subject(s)
Breast Neoplasms/surgery , Carcinoma/surgery , Mammaplasty/methods , Breast Implants , Female , Humans , Mammaplasty/standards , Mammaplasty/trends , Patient Satisfaction , Radiotherapy, Adjuvant , Surgical Flaps/blood supply , Surgical Flaps/physiology , Time Factors
8.
Eur J Vasc Endovasc Surg ; 36(4): 449-51, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18524650

ABSTRACT

INTRODUCTION: Groin lymphatic fistulas are a troublesome finding after limb revascularization surgery. Its management represents a difficult task for the clinician. REPORT: We report our experience in the treatment of such a condition with negative-pressure wound therapy (NPWT) in a 70-year-old man which benefited from extra-anatomic prosthetic axillofemoral bypass. After a week of treatment, the fistula dried up and closure was obtained with simple suture under local anaesthesia. Follow-up at 9 months showed stable coverage without any sign of leakage. DISCUSSION: This study depicts NPWT as an effective non-invasive treatment in the management of groin lymphocutaneous fistula.


Subject(s)
Cutaneous Fistula/therapy , Fistula/therapy , Groin , Lymphatic Diseases/therapy , Negative-Pressure Wound Therapy , Aged , Blood Vessel Prosthesis Implantation/adverse effects , Femoral Artery/surgery , Humans , Male
9.
Acta Chir Belg ; 107(6): 703-5, 2007.
Article in English | MEDLINE | ID: mdl-18274191

ABSTRACT

The authors report their experience in the treatment of a posttraumatic enterocutaneous fistula with negative-pressure therapy. After sustaining an epigastric shot wound, a 33-year-old woman underwent three consecutive laparotomies, which eventually led to an open abdomen with the interposition of a surgical mesh. Enterocutaneous fistulae were subsequently documented and vacuum-assisted closure therapy was instituted along with total parenteral nutrition and systemic antibiotics. Development of a suitable granulation bed and closure of the fistulae were noted after two weeks of treatment and a split-thickness skin graft was applied to the wound. Follow-up at 8 months showed stable coverage and a return to normal enteral feeding.


Subject(s)
Intestinal Fistula/surgery , Negative-Pressure Wound Therapy , Adult , Female , Granulation Tissue/pathology , Humans , Parenteral Nutrition , Skin Transplantation
10.
Eur J Neurosci ; 23(12): 3368-74, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16820026

ABSTRACT

Motherhood modifies the biology and behavior of the female, a process which prepares the mother's cognitive systems that are needed for nurturance. It has recently been shown that motherhood enhances hippocampal-mediated spatial learning and synaptic plasticity. Deleterious and long-term effects of a stress experienced during gestation have been demonstrated on progeny. Surprisingly little is known about the effect of such stress on mothers. Here, we investigated the effect of gestational stress on the adaptive changes due to motherhood. Female rats were mated and stressed during the last week of gestation. Two weeks after weaning, they were submitted to behavioral tests or electrophysiological study. A group of females were then kept for 16 months after motherhood experience to study the long-term effect of gestational stress and motherhood on memory when they were 22 months old. We confirm that a single motherhood experience selectively increases hippocampal-mediated spatial memory during the entire lifespan of female rats and protects them from age-associated memory impairments. However, we demonstrate that a stressful experience during gestation totally abolishes the positive effects of motherhood both on spatial memory and on hippocampal synaptic plasticity (long-term potentiation). Environmental factors that induce biological vulnerability have negative effects even for fundamental biological behaviors.


Subject(s)
Memory/physiology , Mothers , Neuronal Plasticity/physiology , Stress, Psychological , Animals , Behavior, Animal/physiology , Electrophysiology , Female , Hippocampus/physiology , Learning/physiology , Life Expectancy , Male , N-Methylaspartate/metabolism , Pregnancy , Rats , Rats, Wistar , alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/metabolism
12.
Eur J Vasc Endovasc Surg ; 29(4): 350-2, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15749034

ABSTRACT

OBJECTIVES: To review and evaluate our experience with carotid artery stenting in the acute treatment of carotid artery dissection (CAD). PATIENTS AND METHODS: Reviewing the charts of our hospital between 2000 and 2001, we found two consecutive patients who benefited from primary stenting for the acute treatment of spontaneous extracranial internal CAD. RESULTS: Primary stenting of the internal carotid artery was successful in both cases without any post-operative complications. Clinical and US duplex scan follow-up confirmed the absence of neurological symptoms and the patency of the internal carotid artery with complete disappearance of the dissection at 36 and 42 months after the procedure, respectively. CONCLUSION: Despite the small number of patients, primary stenting for acute CAD seems to be safe and effective.


Subject(s)
Carotid Artery, Internal, Dissection/surgery , Stents , Acute Disease , Angiography , Carotid Artery, Internal, Dissection/diagnostic imaging , Humans , Male , Middle Aged , Treatment Outcome , Ultrasonography, Doppler, Duplex
13.
Surg Radiol Anat ; 27(1): 33-6, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15592932

ABSTRACT

The purpose of this study was to assess the relevance of the tip of the greater horn of the hyoid bone (THB) in the localization of the carotid bifurcation, the superior thyroid and lingual arteries, and the hypoglossal and superior laryngeal nerves. Measurements of these structures with respect to the THB were also made. Thirty perfusion-fixed human cadavers (60 specimens) were studied. Sharp measurements were made along two orthogonal axes crossing exactly on the THB. The vertical axis was parallel to the craniocaudal axis of the body. Taking the THB as a landmark, the five structures were identified in all the specimens. The mean value, standard deviation, and range of measurements for each structure studied are given in the text. This study shows the THB to be a useful landmark which is an aid to locating the aforementioned structures with confidence, and concludes that knowledge of this landmark would be beneficial for the surgeon dealing with the mid neck area.


Subject(s)
Hyoid Bone/anatomy & histology , Aged , Arteries/anatomy & histology , Cadaver , Carotid Arteries/anatomy & histology , Female , Humans , Hypoglossal Nerve/anatomy & histology , Laryngeal Nerves/anatomy & histology , Male , Neck/anatomy & histology
14.
Neurobiol Aging ; 26(1): 103-14, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15585350

ABSTRACT

Age-dependent cognitive impairments have been correlated with functional and structural modifications in the hippocampal formation. In particular, the brain endogenous steroid pregnenolone-sulfate (Preg-S) is a cognitive enhancer whose hippocampal levels have been linked physiologically to cognitive performance in senescent animals. However, the mechanism of its actions remains unknown. Because neurogenesis is sensitive to hormonal influences, we examined the effect of Preg-S on neurogenesis, a novel form of plasticity, in young and old rats. We demonstrate that in vivo infusion of Preg-S stimulates neurogenesis and the expression of the polysialylated forms of NCAM, PSA-NCAM, in the dentate gyrus of 3- and 20-month-old rats. These influences on hippocampal plasticity are mediated by the modulation of the gamma-aminobutyric acid receptor complex A (GABA(A)) receptors present on hippocampal neuroblasts. In vitro, Preg-S stimulates the division of adult-derived spheres suggesting a direct influence on progenitors. These data provide evidence that neurosteroids represent one of the local secreted signals controlling hippocampal neurogenesis. Thus, therapies which stimulate neurosteroidogenesis could preserve hippocampal plasticity and prevent the appearance of age-related cognitive disturbances.


Subject(s)
Gene Expression Regulation/drug effects , Hippocampus/cytology , Neural Cell Adhesion Molecule L1/metabolism , Neuronal Plasticity/drug effects , Neurons/drug effects , Pregnenolone/pharmacology , Sialic Acids/metabolism , Age Factors , Analysis of Variance , Animals , Bromodeoxyuridine/metabolism , Cell Count/methods , Dose-Response Relationship, Drug , Hippocampus/drug effects , Hippocampus/physiology , Injections, Intraventricular/methods , Male , Microscopy, Immunoelectron/methods , Neurons/metabolism , Neurons/ultrastructure , Rats , Rats, Sprague-Dawley , Receptors, GABA-A/metabolism , Time Factors
15.
J Reconstr Microsurg ; 20(7): 511-7, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15534777

ABSTRACT

Diabetic patients, presenting with both peripheral vascular disease and large soft-tissue defects, are too often treated by primary amputation. A combined revascularization and free-tissue transfer procedure can extend limb salvage in these patients. The authors report their experience over 4 years with 19 diabetic patients with peripheral vascular disease and large soft-tissue defects of the foot requiring free-tissue transfer. Although there was a 100 percent flap survival, early local wound problems occurred in three patients (16.6 percent). The recurrence rate was about 18.7 percent, but no complementary flap procedures were mandatory. With a mean follow-up of 38 months (range: 23 to 55 months), the limb salvage rate was 94.4 percent. Although there was one limb loss and one patient with ambulation difficulties, 16 patients (84.2 percent) were fully rehabilitated and were able to function independently. Despite a rather small series, this study confirms that in selected diabetic patients, a combined approach of vascular and reconstructive surgeons can reduce the limb amputation rate with acceptable complication rates. This combined approach offers major benefits to these patients, especially stable coverage and preservation of ambulation, and should always be considered before amputation.


Subject(s)
Diabetic Angiopathies/surgery , Diabetic Foot/surgery , Foot/blood supply , Ischemia/surgery , Surgical Flaps , Adult , Aged , Amputation, Surgical , Blood Vessel Prosthesis , Cohort Studies , Debridement , Female , Femoral Artery/surgery , Follow-Up Studies , Graft Survival , Humans , Male , Middle Aged , Muscle, Skeletal/transplantation , Popliteal Artery/surgery , Recurrence , Surgical Wound Infection/etiology , Treatment Outcome
16.
Neurotox Res ; 6(7-8): 571-80, 2004.
Article in English | MEDLINE | ID: mdl-15639789

ABSTRACT

Environmental challenges profoundly modify phenotypes and disrupt inherent developmental programs both at functional and structural levels. As an example, we have studied the impact of these environmental influences on adult neurogenesis in the dentate gyrus. Neurogenesis results from an inherent program, participates to hippocampal network organization and, as a consequence, to the various functional abilities depending on this region, including memories. In preclinical studies of aging we have shown that phenotypes vulnerable to the development of spatial memory disorders are characterized by lower hippocampal neurogenesis. We have hypothesized that these interindividual variations in functional expression of neurogenesis in senescent subjects could be predicted early in life. Indeed, a behavioral response (novelty-induced locomotor reactivity) and a biological trait (hypothalamo-pituitary-adrenal axis activity), which are predictive of cognitive impairments later in life, are related to neurogenesis in young adult rats. This suggests that subjects starting off with an impaired neurogenesis, here rats that are high reactive to stress, are predisposed for the development of age-related cognitive disorders. We have further shown that these inter-individual differences result from early deleterious life events. Indeed, prenatal stress orients neurogenesis in pathological ways for the entire life, and precipitates age-related cognitive impairments. Altogether these data suggest first that hippocampal neurogenesis plays a pivotal role in environmentally-induced vulnerability to the development of pathological aging, and second that environmental challenges and life events orient structural developments, leading to different phenotypes.


Subject(s)
Cues , Environment , Hippocampus/cytology , Orientation/physiology , Animals , Cell Differentiation/physiology , Exploratory Behavior/physiology , Hippocampus/physiology , Humans , Spatial Behavior/physiology , Time
17.
Ann Chir Plast Esthet ; 48(4): 205-10, 2003 Aug.
Article in French | MEDLINE | ID: mdl-12927879

ABSTRACT

The authors report on 8 cases of free flaps with vascular pedicle disruption that were encountered between postoperative days 8 to 18. In one case, the inflow disappeared 18 months after the transfer without any trouble. This resulted in 2 partial and one complete flap losses. The 4 other flaps survived completely. This complete survival is related to the angiogenesis process coming from the surrounding tissues. The most obvious causal factor responsible for the 2 partial losses was the coverage of large, non viable areas, such as a prosthetic material and bone deprived of periosteum. The only causal factor that could be assessed in the case of total necrosis was the presence of an immunosuppressive treatment. Variables participating in the installation of an adequate angiogenic response are then discussed in accordance to this experience and to the literature. Limited contact with viable tissue, ischemia-reperfusion or drugs limiting the angiogenesis seems to promote failure when the pedicle is quickly disrupted. Hypoxia seems to be the most important cellular mechanism promoting the angiogenesis in this context.


Subject(s)
Neovascularization, Physiologic , Plastic Surgery Procedures , Postoperative Complications , Surgical Flaps , Aged , Female , Humans , Hypoxia , Immunosuppressive Agents/adverse effects , Male , Middle Aged , Necrosis , Risk Factors , Treatment Outcome
18.
Int J Pharm ; 258(1-2): 95-107, 2003 Jun 04.
Article in English | MEDLINE | ID: mdl-12753757

ABSTRACT

Biodegradable, porous microspheres exhibit a wide range of release profiles. We propose in this paper a unifying approach based on the dual action of diffusion and erosion to establish which mechanisms are responsible for the variety of release kinetics observed during in vitro experiments. Our modeling procedure leads to the partitioning of the matrix into multiple, identical elements, thus simplifying significantly the mathematical and numerical treatment of the problem. The model equations cannot be solved analytically, since the domain contains a moving interface, and must therefore be solved numerically, using specific methods designed for that purpose. Our model confirms the major role that the relative dominance between diffusion and erosion plays in the release kinetics. In particular, the velocity of erosion, the effective diffusion coefficient of the drug molecule in the wetted polymer, the average pore length, and the initial pore diameter are sensitive parameters, whereas the porosity and the effective diffusion coefficient of the drug in the solvent-filled pores is seen to have little influence, if any, on the release kinetics. The model is confirmed by using release data from biodegradable microspheres with different ratios of low and high molecular weight PLA. Excellent goodness of fit is achieved by varying two parameters for all types of experimental kinetics: from the typical square root of time profile to zero-order kinetics to concave release curves. We are also able to predict, by interpolation, release curves from microspheres made of intermediate, untested ratios of PLA by using a relation between two model parameters.


Subject(s)
Biocompatible Materials/chemistry , Delayed-Action Preparations/chemistry , Models, Chemical , Kinetics , Porosity , Solubility
19.
Genet Couns ; 14(4): 395-400, 2003.
Article in English | MEDLINE | ID: mdl-14738112

ABSTRACT

From January 1st 1990 until December 31st 2001, we collected 19686 prenatal diagnosis (on amniocentesis and chorius villus sampling). Five hundred twelve samples (2.6%) concerned 278 twin pregnancies. The most frequent indications were maternal age > or = 35 years (108/278 = 38.8%), medically assisted procreation (34/278 = 12.3%), positive ultrasound (20/278 = 7.2%). Chromosome abnormalities were found in eight twin-pregnancies (2.9%): five with only one fetus affected [47,XX,+ 18; 45,XX,t( 13;14); 47,XYY; 47,XXX; 45,XX, t(13;14)], two with both fetuses showing the same chromosomal abnormality [inv(11)(q21q25); 47,XX,+ 18] and one with only one fetus tested [47,XX,+ 18]. In total, we found eight autosomal abnormalities, four inherited balanced rearrangements (two robertsonian translocations and two paracentric inversions of chromosome 11) and four trisomies 18. We also observed two sex chromosome abnormalities interesting only one of the two fetuses. Surprisingly, we did no detect any Down Syndrome among this population. The frequency of Down Syndrome was significantly (p < 0.05) lower in our population of twin pregnancies (0.0%) as compared to the observed incidence in singleton pregnancies during the same period (163/19162 = 0.9%).


Subject(s)
Diseases in Twins/epidemiology , Down Syndrome/epidemiology , Adult , Belgium/epidemiology , Chromosome Aberrations/statistics & numerical data , Cytogenetic Analysis , Female , Humans , Incidence , Male , Maternal Age , Pregnancy , Prenatal Diagnosis , Retrospective Studies
20.
Rev Med Liege ; 57(9): 587-90, 2002 Sep.
Article in French | MEDLINE | ID: mdl-12440347

ABSTRACT

Association between deep venous thrombosis (DVT) and pulmonary embolism is probably an underestimated problem in the thermally injured patients. However, those patients display important risk factors according to Virchow's triad. This article reports on three unrecognised DVT's accompanying burns which were characterized by absence of healing or edema. The pathophysiology of this issue is then discussed with respect to the specific area of the thermally injured patient. It is our belief that local inflammatory phenomenon play a major part in the genesis of DVT associated with chronic non-healing burns.


Subject(s)
Burns/complications , Pulmonary Embolism/etiology , Venous Thrombosis/etiology , Adult , Child , Humans , Inflammation , Male , Middle Aged , Risk Factors , Wound Healing
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