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1.
Musculoskeletal Care ; 22(2): e1899, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38831384

ABSTRACT

BACKGROUND: Medical guidelines recommend structured prehabilitation protocols consisting of lifestyle modifications and exercise to enhance post-operative outcomes for patients undergoing a total knee replacement (TKR). However, current research showing effectiveness is limited and has primarily focused on outcomes of exercise-based prehabilitation. OBJECTIVES: To investigate whether a structured prehabilitation protocol consisting of exercise and lifestyle modifications improves physical function and patient-reported outcomes following TKR surgery compared with usual care. DESIGN: Systematic review. METHODS: Five databases were searched to identify randomised controlled trials comparing structured prehabilitation programs consisting of lifestyle modifications and exercise, with usual care, for those undergoing a TKR. Methodological quality of included studies was assessed via the RoB 2.0 tool and results synthesis via a Grading of Recommendation Assessment, Development and Evaluation approach was performed to determine the certainty evidence for each outcome. RESULTS/FINDINGS: Four studies were included in this review. Despite a positive trend supporting the inclusion of a structured prehabilitation protocol, additional improvements in post-operative pain, physical function and self-reported function were only seen in one study. Reductions in hospital length of stay were also seen in one study. No additional improvements in post-operative quality of life following prehabilitation were reported. CONCLUSION: Limited evidence supporting prehabilitation reported in our review is likely attributed to the intervention type, intensity, and delivery model of included studies. However, there remains to be strong evidence supporting the use of a structured prehabilitation protocol consisting of lifestyle modifications and exercise to improve post-operative outcome.


Subject(s)
Arthroplasty, Replacement, Knee , Preoperative Exercise , Humans , Arthroplasty, Replacement, Knee/rehabilitation , Exercise Therapy , Life Style , Treatment Outcome , Preoperative Care
2.
Philos Trans A Math Phys Eng Sci ; 376(2124)2018 Jul 28.
Article in English | MEDLINE | ID: mdl-29891503

ABSTRACT

Prigogine's ideas of systems far from equilibrium and self-organization (Prigogine & Lefever. 1968 J. Chem. Phys.48, 1695-1700 (doi:10.1063/1.1668896); Glansdorff & Prigogine. 1971 Thermodynamic theory of structures, stability and fluctuations New York, NY/London, UK: Wiley) deeply influenced physics, and soliton science in particular. These ideas allowed the notion of solitons to be extended from purely integrable cases to the concept of dissipative solitons. The latter are qualitatively different from the solitons in integrable and Hamiltonian systems. The variety in their forms is huge. In this paper, one recent example is considered-dissipative solitons with extreme spikes (DSESs). It was found that DSESs exist in large regions of the parameter space of the complex cubic-quintic Ginzburg-Landau equation. A continuous variation in any of its parameters results in a rich structure of bifurcations.This article is part of the theme issue 'Dissipative structures in matter out of equilibrium: from chemistry, photonics and biology (part 1)'.

3.
Phys Rev E ; 94(2-1): 022212, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27627303

ABSTRACT

Turbulence in integrable systems exhibits a noticeable scientific advantage: it can be expressed in terms of the nonlinear modes of these systems. Whether the majority of the excitations in the system are breathers or solitons defines the properties of the turbulent state. In the two extreme cases we can call such states "breather turbulence" or "soliton turbulence." The number of rogue waves, the probability density functions of the chaotic wave fields, and their physical spectra are all specific for each of these two situations. Understanding these extreme cases also helps in studies of mixed turbulent states when the wave field contains both solitons and breathers, thus revealing intermediate characteristics.

4.
Phys Rev Lett ; 116(10): 103901, 2016 Mar 11.
Article in English | MEDLINE | ID: mdl-27015481

ABSTRACT

Turbulence in dynamical systems is one of the most intriguing phenomena of modern science. Integrable systems offer the possibility to understand, to some extent, turbulence. Recent numerical and experimental data suggest that the probability of the appearance of rogue waves in a chaotic wave state in such systems increases when the initial state is a random function of sufficiently high amplitude. We provide explanations for this effect.

5.
Science ; 351(6271): 340-1, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26798000
6.
Article in English | MEDLINE | ID: mdl-25314499

ABSTRACT

We study the properties of the chaotic wave fields generated in the frame of the Sasa-Satsuma equation (SSE). Modulation instability results in a chaotic pattern of small-scale filaments with a free parameter-the propagation constant k. The average velocity of the filaments is approximately given by the group velocity calculated from the dispersion relation for the plane-wave solution. Remarkably, our results reveal the reason for the skewed profile of the exact SSE rogue-wave solutions, which was one of their distinctive unexplained features. We have also calculated the probability density functions for various values of the propagation constant k, showing that probability of appearance of rogue waves depends on k.


Subject(s)
Nonlinear Dynamics , Oceans and Seas , Probability Theory
7.
Opt Express ; 17(6): 4236-50, 2009 Mar 16.
Article in English | MEDLINE | ID: mdl-19293847

ABSTRACT

We study dissipative ring solitons with vorticity in the frame of the (2+1)-dimensional cubic-quintic complex Ginzburg-Landau equation. In dissipative media, radially symmetric ring structures with any vorticity m can be stable in a finite range of parameters. Beyond the region of stability, the solitons lose the radial symmetry but may remain stable, keeping the same value of the topological charge. We have found bifurcations into solitons with n-fold bending symmetry, with n independent on m. Solitons without circular symmetry can also display (m + 1)-fold modulation behaviour. A sequence of bifurcations can transform the ring soliton into a pulsating or chaotic state which keeps the same value of the topological charge as the original ring.

9.
Opt Express ; 16(20): 15388-401, 2008 Sep 29.
Article in English | MEDLINE | ID: mdl-18825175

ABSTRACT

Dissipative media admit the existence of two types of stationary self-organized beams: continuously self-focused and continuously self- defocused. Each beam is stable inside of a certain region of its existence. Beyond these two regions, beams loose their stability, and new dynamical behaviors appear. We present several types of instabilities related to each beam configuration and give examples of beam dynamics in the areas adjacent to the two regions. We observed that, in one case beams loose the radial symmetry while in the other one the radial symmetry is conserved during complicated beam transformations.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(1 Pt 2): 016613, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17358281

ABSTRACT

We show, numerically, that coupled soliton pairs in nonlinear dissipative systems modeled by the cubic-quintic complex Ginzburg-Landau equation can exist in various forms. They can be stationary, or they can pulsate periodically, quasiperiodically, or chaotically, as is the case for single solitons. In particular, we have found various types of vibrating and shaking soliton pairs. Each type is stable in the sense that a given bound state exists in the same form indefinitely. New solutions appear at special values of the equation parameters, thus bifurcating from stationary pairs. We also report the finding of mixed soliton pairs, formed by two different types of single solitons. We present regions of existence of the pair solutions and corresponding bifurcation diagrams.

12.
Curr Alzheimer Res ; 4(1): 81-93, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17316169

ABSTRACT

In this 10-week, double-blind, fixed-dose study, elderly institutionalized patients with dementia and agitation were randomized (3:3:2) to quetiapine 200mg/day, 100mg/day, or placebo. The primary endpoint was change in Positive and Negative Syndrome Scale (PANSS)-Excitement Component (EC) scores at endpoint, analysed using last observation carried forward (LOCF) and observed cases (OC) approaches. Other efficacy measures were the Clinical Global Impression of Change (CGI-C), and response rates (percentage with > or =40% reduction [PANSS-EC]; "much" or "very much improved" [CGI-C]), Neuropsychiatric Inventory-Nursing Home version (NPI-NH), and Cohen-Mansfield Agitation Inventory (CMAI). The key safety measure was incidence of adverse events; change in Mini-Mental State Examination (MMSE) was also assessed. Baseline characteristics of 333 participants (quetiapine 200mg/day, n=117; quetiapine 100mg/day, n=124; placebo, n=92) and completion rates (63-65%) were comparable among groups. Compared with placebo, quetiapine 200mg/day was associated with clinically greater improvements in PANSS-EC (LOCF, p=0.065; OC, p=0.014 [ANCOVA]), CGI-C (LOCF, p=0.017; OC, p=0.002 [ANOVA]), and CGI-C response rates (LOCF, p=0.002; OC, p<0.001 [Chi-square test]). Quetiapine 100mg/day did not differentiate from placebo on these measures. There were no between-group differences in NPI-NH or CMAI. Incidences of cerebrovascular adverse events, postural hypotension, and falls were similar among groups. MMSE did not change in any group. Mortality was numerically higher in the quetiapine groups; rates were not statistically different from placebo. The results of this study suggest that quetiapine 200mg/day was effective and well-tolerated for treating agitation associated with dementia. However, caution should be exercised given the concerns regarding increased mortality with atypical antipsychotics in this vulnerable patient population.


Subject(s)
Antipsychotic Agents/therapeutic use , Dementia/complications , Dibenzothiazepines/therapeutic use , Psychomotor Agitation/drug therapy , Psychomotor Agitation/etiology , Aged , Aged, 80 and over , Analysis of Variance , Dose-Response Relationship, Drug , Double-Blind Method , Female , Follow-Up Studies , Humans , Male , Middle Aged , Psychiatric Status Rating Scales , Quetiapine Fumarate , Retrospective Studies , Treatment Outcome
13.
Bipolar Disord ; 6(3): 213-23, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15117400

ABSTRACT

OBJECTIVE: Evaluate the efficacy and tolerability of quetiapine (QTP) combined with lithium (Li) or divalproex (DVP) in the treatment of acute mania. METHODS: Patients were randomized to 21 days of double-blind treatment with QTP plus Li/DVP, or placebo (PBO) plus Li/DVP. QTP was rapidly dosed up to a maximum of 800 mg/day; Li was dosed to 0.7-1.0 mEq/L; or DVP to 50-100 microg/mL. RESULTS: Fifty-six of 91 (61.5%) individuals in the QTP + Li/DVP group compared with 49 of 100 (49%) taking PBO + Li/DVP completed the study. A significantly greater mean reduction in total Young Mania Rating Scale (YMRS) score was observed at end-point in patients receiving QTP + Li/DVP compared with those in the PBO + Li/DVP group (-13.76 versus -9.93; p = 0.021). The response rate (> or =50% YMRS improvement) was significantly higher in the QTP + Li/DVP group than in PBO + Li/DVP-treated patients (54.3% versus 32.6%; p = 0.005), as was the proportion of patients achieving clinical remission (YMRS < 12) (45.7% versus 25.8%; p = 0.007). Patients receiving QTP + Li/DVP also had a significantly greater improvement in Clinical Global Impressions-Bipolar (CGI-BP) Severity of Illness scores (-1.38 versus -0.78; p = 0.001). The mean last-week dose of QTP was 584 mg/day in patients meeting response criteria. Common adverse events (at least 10% and twice the rate of Li/DVP) in the QTP + Li/DVP group included somnolence, dry mouth, asthenia, and postural hypotension. CONCLUSIONS: Quetiapine combined with either Li or DVP has superior efficacy compared with Li or DVP monotherapy for treating patients with bipolar mania. Combination therapy was well-tolerated and most adverse events were mild, withdrawal because of adverse events being only 5% compared with 6% on Li or DVP monotherapy.


Subject(s)
Anticonvulsants/therapeutic use , Antipsychotic Agents/therapeutic use , Bipolar Disorder/drug therapy , Dibenzothiazepines/therapeutic use , Lithium Carbonate/therapeutic use , Valproic Acid/therapeutic use , Adult , Anticonvulsants/adverse effects , Antipsychotic Agents/adverse effects , Dibenzothiazepines/adverse effects , Double-Blind Method , Electrocardiography , Female , Humans , Lithium Carbonate/adverse effects , Male , Quetiapine Fumarate , Valproic Acid/adverse effects
15.
Pediatrics ; 102(2 Pt 3): 486-8, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9685449

ABSTRACT

Estrogen has a biphasic effect on growth, stimulatory at low doses but inhibitory at higher doses. Therefore, designing optimal sex hormone replacement treatment in girls with Turner syndrome (TS) who are being treated with growth hormone (GH) involves considering the dose and form of the estrogen as well as the route and timing of its administration. We report here a preliminary analysis of a study to test the concept that an optimal estrogen replacement regimen should consist of estradiol administered in a low dose by a systemic route. The study population consisted of 9 girls with TS who had been treated with GH for 6 or more months. When the girls were 12 to 15 years old, we added depot estradiol at a monthly intramuscular dose of 0.2 mg and increased the dose at 6-month intervals to 0.4, 0.6, and, in 7 of the girls, 0.8 mg. We compared the results in these subjects with those in a matched group of 37 patients with TS in whom routine estrogen treatment had been started at similar ages and who were treated with a similar course of GH therapy. The gain in height at 2 years was 2.6 cm greater in those who were treated with depot estradiol than in those who were treated with routine estrogen. The bone age in the patients who were treated with depot estradiol increased in proportion to their chronologic age, suggesting that this difference indicates an increase in their predicted adult height. We conclude that using very low doses of systemic estradiol to induce puberty before the age of 15 years in girls with TS who are treated with GH, instead of using routine estrogen therapy, can result in increased final heights.


Subject(s)
Estrogen Replacement Therapy , Growth Disorders/therapy , Turner Syndrome/therapy , Adolescent , Body Height , Child , Delayed-Action Preparations , Estradiol/administration & dosage , Estrogen Replacement Therapy/methods , Female , Growth Disorders/complications , Growth Hormone/therapeutic use , Humans , Turner Syndrome/complications , Turner Syndrome/physiopathology
16.
Eur Radiol ; 7(6): 847-53, 1997.
Article in English | MEDLINE | ID: mdl-9228099

ABSTRACT

In spite of improvements in single or double lung transplantation (LT) technique, complications after LT are not uncommon; the most frequent ale anastomotic complications, infections and rejection (acute or chronic). Early detection of complications of LT allows the optimal therapeutic option to be taken, yielding decreased morbidity and mortality. In some cases, CT plays a key role in early detection of several complications of LT that may not be depicted with other diagnostic modalities, so that knowledge of their CT features is important. In this pictorial review, the authors describe the spectrum of CT features of the complications of LT (including reimplantation response, mechanical problems, acute and chronic rejection, infection, lymphoproliferative disorders, recurrence of the initial disease and complications involving the pleura and the anastomotic sites). In addition, the authors analyze the value of CT compared to that of the other available modalities for the detection of complications of LT.


Subject(s)
Lung Transplantation/adverse effects , Tomography, X-Ray Computed , Adult , Anastomosis, Surgical , Biopsy, Needle/adverse effects , Bronchi/surgery , Female , Graft Rejection/diagnostic imaging , Humans , Lung/diagnostic imaging , Lymphoproliferative Disorders/diagnostic imaging , Lymphoproliferative Disorders/etiology , Male , Middle Aged , Opportunistic Infections/diagnostic imaging , Pneumothorax/diagnostic imaging , Pneumothorax/etiology , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/etiology
17.
J Radiol ; 77(7): 477-81, 1996 Jul.
Article in French | MEDLINE | ID: mdl-8760614

ABSTRACT

PURPOSE: To determine the sensitivity and specificity of CT in depicting bronchial anastomotic complications after lung transplantation. MATERIALS AND METHODS: A retrospective, blinded review of 105 CT scans obtained after single (n = 17) or double (n = 10) lung transplantation in 27 patients was done by two radiologists in consensus. CT images, were analyzed with respect to the status of bronchial anastomoses, with three possible answers given to the readers: normal, dehiscence, or stenosis. CT features were correlated to bronchoscopic and follow-up findings, which were considered as standard of reference. RESULTS: CT had a 60% sensitivity and 98% specificity for the diagnosis of bronchial dehiscence, and 40% and 99% for the diagnosis of anastomotic stenosis. One case of bronchial disruption was diagnosed on CT scan only and subsequently confirmed by repeated bronchoscopy. CONCLUSION: In our study, CT has a low sensitivity but a high specificity in the detection of bronchial anastomotic complications after lung transplantation. However, CT remains useful in some cases, as it can show complications not seen bronchoscopically.


Subject(s)
Bronchi/surgery , Lung Transplantation/adverse effects , Suture Techniques/adverse effects , Adult , Anastomosis, Surgical/adverse effects , Bronchoscopy , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Sensitivity and Specificity , Tomography, X-Ray Computed
18.
Abdom Imaging ; 21(4): 324-8, 1996.
Article in English | MEDLINE | ID: mdl-8661569

ABSTRACT

BACKGROUND: The purpose of this study was to determine the prevalence of hepatic pseudolesions seen around the falciform ligament on computed tomography (CT) of the abdomen obtained with intravenous administration of contrast material. METHODS: We first retrospectively reviewed the CT scans of six patients in whom hepatic pseudolesions were seen around the falciform ligament. The abdominal CT scans of 587 patients were then prospectively analyzed for the presence of hepatic pseudolesions around the falciform ligament to determine the prevalence of this finding on CT examinations. RESULTS: CT scans in the first six patients showed two types of hepatic pseudolesion around the falciform ligament. In three patients, hepatic pseudolesions were focal spared areas in fatty liver. In three patients, hepatic pseudolesions were developed in nonfatty liver. Prospectively, hepatic pseudolesions were found on five of 587 CT examinations (prevalence = 1%). A single hepatic pseudolesion was found in segment 4 on two examinations. Two hepatic pseudolesions (one in segment 4 and one in segment 3) were found together on three CT examinations. CONCLUSION: Hepatic pseudolesions around the falciform ligament are seldom seen on CT scan. However, recognition of these pseudolesions is crucial because they may be interpreted as true tumors.


Subject(s)
Ligaments/diagnostic imaging , Liver Diseases/diagnostic imaging , Liver/diagnostic imaging , Tomography, X-Ray Computed , Adult , Aged , Aged, 80 and over , Contrast Media/administration & dosage , Diagnosis, Differential , Fatty Liver/diagnostic imaging , Female , Follow-Up Studies , Humans , Injections, Intravenous , Liver Neoplasms/diagnostic imaging , Male , Middle Aged , Prevalence , Prospective Studies , Radiography, Abdominal , Retrospective Studies
19.
Phys Rev Lett ; 75(24): 4369-4372, 1995 Dec 11.
Article in English | MEDLINE | ID: mdl-10059891
20.
AJR Am J Roentgenol ; 164(3): 631-5, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7863884

ABSTRACT

The pancreas is located deep within the retroperitoneum in the anterior pararenal space. The distal portion of the pancreatic tail extends along the course of the splenic artery and vein (Fig. 1) and enters the splenic hilum contained within the splenorenal ligament. Because of these anatomic relationships, the spleen and splenic vessels may be involved by pancreatitis. Although rare (frequency, 1-5%), splenic involvement by pancreatitis includes intrasplenic pseudocyst, abscess, hemorrhage, infarction, splenic rupture, and vascular injury. Because these complications can be life-threatening, the extent and course of the disease are closely monitored with CT to determine whether and when aggressive intervention is necessary to avoid catastrophic clinical outcomes. The purpose of this essay is to illustrate the spectrum of CT findings in cases of pancreatitis with splenic involvement.


Subject(s)
Pancreatitis/diagnostic imaging , Splenic Diseases/diagnostic imaging , Tomography, X-Ray Computed , Humans , Pancreatitis/complications , Spleen/diagnostic imaging , Splenic Diseases/etiology
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