Effectiveness of Kinesiotaping and McConnell taping combined with physical exercise on gait biomechanics in patients with patellofemoral syndrome: non-randomized clinical trial

Background

Patellofemoral pain syndrome (PFPS) is a pathological condition of the knee, typical of young adults, characterized by diffuse pain in the anterior and / or medial part of the knee. We aimed to examine the effectiveness of the two types of taping in association with therapeutic exercise in relation to the biomechanical parameters, on pain and on functionality of the lower limb in patients with PFPS.

Methods

We collected data from patients treated in our outpatient's clinic with two kinds of bandage: the Kinesiotaping group (KG) and the McConnel taping group (MG). All subjects were evaluated trough an optoelectronic system, the Numeric Pain Rating Scale (NPRS), and with the Lower Extremity Functional Scale (LEFS) at baseline before applying the taping (T0), fifteen minutes after applying the bandage (T1), after four weeks of treatment (T2) without applying the bandage and three months after the end of the first treatment period with bandages and exercises (T3).

Results

Thirty-five patients (KG 16; MG 19) were included in the study. The most statistically significant changes over time in the LEFS and NPRS values have been recorded in the MG group compared to KG. The average speed and hip rotation showed a statistically significant increase between T3 and T0.

Conclusion

The application of the knee bandage for PFPS would appear to show improvement in NPRS and LEFS outcomes in both groups. Furthermore, in this study the MG evidenced better results and significant changes over time than KG.

Efficacy of ultrasound therapy combined with cryotherapy in pain management and rehabilitation in patients with Achilles tendinopathy: a retrospective observational study

Background

Achilles tendinopathy (AT) is characterized by pain, reduced performance, and swelling in and around the tendon. The aim of our study was to evaluate and compare the effects of ultrasound therapy alone or associated with cryotherapy.

Methods

We analyzed retrospectively amateur runner patients who run at least 3 times a week, with medical and ultrasound diagnosis of subacute AT of the midportion. All patients underwent 10 sessions of ultrasounds' therapy with qmd® ultrasound cryo and a therapeutic exercise with stretching and eccentric exercises. The Cryo-Ultrasound Group (CUG, 15, 8M and7/F), during the ultrasound treatment, underwent a session of cryo-ultrasound therapy. The Ultrasound Group (UD, 15, 7M and 8F) only performed ultrasound therapy.

Results

All evaluations performed show significant improvement over time in both groups. The CUG shows at T1 a greater increase in pain and function compared to the UG. Friedmann's repeated measures analysis shows that both groups improved when assessed separately over time. From the subsequent post hoc analysis, a statistically significant difference is highlighted between the values evaluated at T0 and T3.

Conclusions

The possible simultaneous delivery of the two treatment modalities, in patients suffering from tendinopathies, therefore represents a good possibility of synergistically exploiting their therapeutic actions. Future studies with a larger patient sample and longer follow-up are also needed to better evaluate the benefits of this treatment.

Gait analysis advancements: rehabilitation value and new perspectives from forensic application

The clinical and rehabilitation value of gait analysis is remarkable and indisputable and poised to grow as technological advancements unfold. This article aims to shed light on the advances in how gait is assessed, enabling those who have suffered an injury impairing their motor skills to be diagnosed more accurately and efficiently as well as to compare the hallmarks of rehabilitative and forensic gait analysis. The authors have conducted an analysis of relevant papers (published between 1967 and 2020) from a medicolegal perspective, cited in PubMed, MEDLINE, Cochrane Library, EMBASE, and available recommendations for the legal application of such techniques. Moreover, considering the use of gait analysis as a forensic tool, this study broadens the scope of research by including search engines, legal databases, and court filings (DeJure, Lexis Nexis, Justia) between 2000 and 2022. The instrumental assessment of movement (Gait Analysis) has come to constitute an essential analytical tool for the biomedical sector to objectively and accurately assess human movement and posture. The article is also aimed at elaborating differences and similarities between clinical and forensic gait analysis. When it comes to the forensic applicability of gait analysis and its evidentiary value, however, there is a pressing need for a review of its scientific basis. Therefore, it is necessary to conduct a thorough evaluation of its use in legal practice, as stressed in scientific literature and surveys. It is of utmost importance to highlight the procedural and assessment standards currently applied to forensic gait analysis, to evaluate its strengths and weaknesses, and to achieve standardized guidelines based on broad scientific consensus.

Impact of Covid-19 pandemic on injection-based practice: report from an Italian multicenter and multidisciplinary survey

BACKGROUND

There are no papers exploring the impact of COVID-19 pandemic on the injection-based practice in patients affected by different rheumatic diseases, including osteoarthritis. The aim was to investigate the impact of COVID-19 pandemic on injection-based practice trough the Italian country.

STUDY DESIGN

A survey-based retrospective cross-sectional study.

METHODS

An Italian-language questionnaire was developed by a group of senior researchers and distributed by e-mail to some Rheumatology, Orthopedic and Rehabilitation Units from different geographic areas of Italy. The survey included information about the number of injections performed during COVID-19 pandemic (stratified by injected agents and injected joint), in comparison to the pre-pandemic period, and the possible reasons behind an eventual reduction. Responses were collected and descriptive analysis calculated.

RESULTS

Eleven centers of the National Health Service completed the survey. The activities of the injections services significantly decreased across the country with a percentage of reduction of 60% compared to the pre-pandemic period. A significant reduction of both intra-articular and peri-articular injections was registered. Among intra-articular. treatments, the most affected ones were the hyaluronic acid injections, when compared to corticosteroids. A significant decrease of the total amount of peri-articular injections was observed. The strict government restrictions and the fear of patients to become infected represented the most limiting factors.

CONCLUSIONS

The reported decrease of the injection-based practice in our country during the COVID-19 pandemic highlights the detrimental effects of the COVID-19 pandemic on the management of chronic musculoskeletal diseases with possible negative consequences in terms of disability and quality of life.

Medical management of osteoarthritis during the CO-VID-19 pandemic: a challenge for the present and the future

The ongoing Covid-19 pandemic has inevitably changed the treatment of many chronic diseases which has been suspended or has suffered dangerous slowdowns. Osteoarthritis (OA) is the most common musculoskeletal disease. As a result, the medical management of Osteoarthritis was heavily impacted by the pandemic, and it required new therapeutic strategies. The purpose of this descriptive review is to provide an overview of how much the pandemic has affected the medical management of osteoarthritis and to outline a number of possible countermeasures. The COVID-19 pandemic requires a "multimodal approach": physicians are called to test the management of Osteoarthritis patients at a distance, through the tools made available by telemedicine, for all cases in which direct contact is avoidable. Therapies that instead require a direct intervention on the patient impose that all the procedures are carried out in complete safety, scrupulously keeping to the use of personal protective equipements.

Trade-Offs with rehabilitation Effectiveness (REs) and Efficiency (REy) in a sample of Italian disabled persons in a in post-acuity rehabilitation unit

BACKGROUND

Intensive Rehabilitation Centres, known in Italy as "code 56", admit patients who need to recover from an acute episode. Different Rehabilitation Impact Indices have been proposed as composite rehabilitation outcomes measuring the rate of improvement due to a rehabilitation program. The most widely employed measure the performance of Activities of daily living in rehabilitation is the modified Barthel Index. The Barthel Index-based Rehabilitation Impact Indices are the Rehabilitation Effectiveness and the Rehabilitation Efficiency.

AIM

The aim of our study was to evaluate the trade-off between Rehabilitation Effectiveness tayand Rehabilitation Efficiency with respect to the Barthel Index admission score and the Length Of Stay, and their ideal ranges that optimized both indices.

METHODS

We retrospectively evaluated data of all patients admitted to intensive rehabilitation unit of the Scientific Institute for Research and Healthcare San Raffaele Pisana of Rome, from January 2006 to March 2018. The primary outcome measures of our study were patient's Rehabilitation Effectiveness and Rehabilitation Efficiency during the hospital stay.

RESULTS

A database of 3,466 patients was analysed and the Rehabilitation Effectiveness and Rehabilitation Efficiency indexes were calculated. We calculated the median rank ratio of the Rehabilitation Effectiveness to the Rehabilitation Efficiency against Barthel Index scores. We calculated the median rank ratio of the Rehabilitation Effectiveness to Rehabilitation Efficiency against Barthel Index scores and days of stay. The median rank ratio of the Rehabilitation Effectiveness to the Rehabilitation Efficiency value were 1 in the range of Barthel Index scores from 32 to 42. The median rank ratio of the Rehabilitation Effectiveness to Rehabilitation Efficiency value were 1 for a Length of Stay corresponding to 33 days.

CONCLUSIONS

In our study we calculated the Trade-offs between Rehabilitation Effectiveness and Rehabilitation Efficiency with respect to admission Barthel Index Score and Length Of Stay in a population of 3,466 patients affected by orthopedic (1,707) and neurological (1,759) diseases. Every member of the healthcare team should be aware of such trade-offs when they make decisions about rehabilitation services.

Idiopathic facial palsy: umbrella review of systematic reviews and meta-analyses

Idiopathic facial palsy is the most common disease of the VII cranial nerve. There are many treatments to facilitate recovery from this condition: pharmacological, surgical, rehabilitative, but the effectiveness of some of these treatments, especially the latter, is still under discussion. The purpose of this umbrella review of systematic reviews is to analyse the literature in order to investigate the different rehabilitation interventions in patients suffering from idiopathic facial palsy. A scientific literature search was carried out from January 2009 until August 2019, using Mesh the terms "facial palsy", "Bell's Palsy", "idiopathic facial nerve palsy", combined with "rehabilitation" and "therapy". Initially all the systematic reviews and meta-analyses of the last 10 years concerning rehabilitation treatments for the recovery of injured functions in facial palsy were included. Given the heterogeneity of the studies in the literature, which do not differentiate the different causes of facial palsy, all the causes of idiopathic facial palsy were included in the review. The research resulted in 94 published systematic reviews but only 6 were considered in respect to the inclusion criteria. All studies agree on the lack of high-quality scientific work to be able to say that Bell's physiotherapy treatments for facial palsy are effective, in particular with regard to recovery times during the rehabilitation process. Future studies are needed, in order to highlight the therapeutic implications of the different rehabilitation methods, with standardized protocols, in patients suffering from facial palsy of different aetiology.

Inter- and intra-interviewer reliability of Italian version of Pediatric Evaluation of Disability Inventory (I-PEDI)

BACKGROUND

Childhood disabilities determine a range of immediate and long-term economic costs that have important implications for the well-being of the child, the family and the society. The Pediatric Evaluation of Disability Inventory (PEDI) measures capability and performance in children aged between 6 months and 7.5 years. It contains three scales: Functional Skills Scales (FSS), Caregiver Assistance Scale (CAS) and Modifications Scale (MS). The present study evaluated the measurement properties of the Italian version of the PEDI (PEDI-I) in patients with spastic cerebral palsy (CP).

STUDY DESIGN

Reliability study.

METHODS

The original PEDI was translated - including a cross-cultural adaptation - into Italian. Internal consistency and test-retest reliability were evaluated.

RESULTS

Fifty-eight children with CP were recruited. According to inter-interviewer reproducibility, the FSS domain revealed intraclass correlation coefficient (ICC) values ranging between 0.94 and 1.00. CAS domain revealed ICC values ranging between 0.94 and 1.00. The SEM values ranged between 3.25 (SDD=8.98) for SF and 5.24 for SC (SDD=14.5). According to intra-interviewer reproducibility, the FSS domain revealed ICC values ranging between 0.99 and 1.00. CAS domain revealed ICC values ranging between 0.92 and 0.99. The SEM values ranged between 3.44 (SDD=9.5) for SF and 3.75 for SC (SDD=10.36). The inter-interviewer and intra-interviewer reproducibility results showed very high ICC values for both FFS and CAS domains. Cronbach's α ranged between 0.94 and 0.99, indicating excellent internal consistency within each domain of the PEDI-I.

CONCLUSION

The inter-interviewer and intra-interviewer reproducibility results of PEDI-I showed very high ICC values for FFS and CAS domains. Therefore, we recommend its application to evaluate the effect of treatment in children with CP.

Extracorporeal shock wave therapy and ultrasound therapy improve pain and function in patients with carpal tunnel syndrome. A randomized controlled trial

BACKGROUND

Ultrasound (US) therapy improves symptoms in carpal tunnel syndrome (CTS) patients. Extracorporeal shock wave therapy (ESWT) uses acoustic energy to determine its clinical effects, as US-therapy does.

AIM

The aim of this study was to compare the short-term efficacy of US and ESWT on mild and moderate CTS.

STUDY DESIGN

Randomized controlled trial.

SETTING

University outpatient service.

POPULATION

Twenty-five patients with mild to moderate CTS, for a total of 42 wrists.

METHODS

patients were randomized to receive US, cryo-US or ESWT, and were evaluated for pain and function before treatment started, at the end of treatment, and four and 12 weeks after the end of the treatment.

RESULTS

Significant improvement was noted in all groups for pain (P<0.05) and functionality (P<0.05). Patients in ESWT group show greater pain improvement at 12-weeks follow-up when compared with both US and cryo-US groups (P<0.05).

CONCLUSION

Patients affected by CTS might benefit from the application of US, cryo-US or ESWT. Benefits persist 3 months after the end of treatment.

CLINICAL REHABIL IMPACT

Clinicians might consider the possibility of a short-term non-surgical management for mild-to-moderate CTS.

Unilateral deep brain stimulation of the pedunculopontine tegmental nucleus in idiopathic Parkinson's disease: effects on gait initiation and performance

The pedunculopontine tegmental nucleus (PPTg) is a component of the locomotor mesencephalic area. In recent years it has been considered a new surgical site for deep brain stimulation (DBS) in movement disorders. Here, using objective kinematic and spatio-temporal gait analysis, we report the impact of low frequency (40 Hz) unilateral PPTg DBS in ten patients suffering from idiopathic Parkinson's disease with drug-resistant gait and axial disabilities. Patients were studied for gait initiation (GI) and steady-state level walking (LW) under residual drug therapy. In the LW study, a straight walking task was employed. Patients were compared with healthy age-matched controls. The analysis revealed that GI, cadence, stride length and left pelvic tilt range of motion (ROM) improved under stimulation. The duration of the S1 and S2 sub-phases of the anticipatory postural adjustment phase of GI was not affected by stimulation, however a significant improvement was observed in the S1 sub-phase in both the backward shift of centre of pressure and peak velocity. Speed during the swing phase, step width, stance duration, right pelvic tilt ROM phase, right and left hip flexion-extension ROM, and right and left knee ROM were not modified. Overall, the results show that unilateral PPTg DBS may affect GI and specific spatio-temporal and kinematic parameters during unconstrained walking on a straight trajectory, thus providing further support to the importance of the PPTg in the modulation of gait in neurodegenerative disorders.

[Role of rifaximin in the treatment of colonic diverticular disease]

Diverticular disease of the colon is the fifth most important gastrointestinal disease in terms of direct and indirect healthcare costs in western countries. Although most patients with colonic diverticula remain asymptomatic for their whole life, in 20-25% of cases will develop symptoms. Antibiotics are commonly used in the treatment of inflammatory complication of diverticular disease. Several clinical observation suggest a role of rifaximin in the management of symptomatic uncomplicated diverticular disease of the colon. This is a critical review of clinical studies addressing the role of long term administration of rifaximin for the treatment of symptomatic colonic diverticular disease. The evidence from prospective controlled trials suggests that rifaximin is effective for obtaining symptomatic relief in patients with uncomplicated diverticular disease. The therapeutic gain compared with fiber supplementation only is approximately 30%. No definitive conclusion can be drawn regard a possible role of rifaximin for preventing diverticulitis.

Natural history of ileo-caecal Crohn's disease after surgical resection. A long term study

AIM

Surgery is an almost inevitable event in Crohn's disease (CD) but is not curative; postoperative recurrence follows a predictable course. Several factors potentially affecting the risk of recurrence have been investigated but results are largely inconclusive. The aim of the present study was to evaluate the long-term course of ileo-caecal CD after surgery and to identify possible predictors of clinical and surgical recurrence.

METHODS

Patients with ileo-caecal CD who had undergone surgical resection and with at least one year of post-operative follow-up were studied. The postoperative course was retrospectively evaluated. The primary end-points were clinical recurrence (defined as reappearance of symptoms requiring steroid treatment in the presence of endoscopic and/or radiologic recurrence) and surgical recurrence, defined as need for reoperation.

RESULTS

Two hundred and twelve patients were included in the study. Median follow-up after surgery was 117 months (interquartile range 51-216). The cumulative probability of a post-operative course without clinical and surgical recurrence after 30, 60, 90, 120 months was 78.2%, 69.4%, 58.0%, 50.6% and 97.0%, 96.4%, 85.6%, 72% respectively. Early surgery (within three years from diagnosis) was associated with a longer postoperative course without clinical recurrence compared with late surgery (performed after three years from diagnosis). None of the other clinical variables considered (gender, age, family history for IBD, smoking habits, pattern of CD, and postoperative prophylactic treatment) was associated with the risk of clinical and surgical recurrence.

CONCLUSION

Surgery is an excellent treatment for patients with isolated ileo-caecal CD. The overall long-term outcome is good: by 10 years after operation approximately 50% of patients are free of clinical recurrence and over 70% do not require further surgery. Surgery, therefore, continues to play an important role in ileo-caecal CD and should therefore not be considered only a failure of medical treatment.

Kinesio Taping applied to lumbar muscles influences clinical and electromyographic characteristics in chronic low back pain patients

BACKGROUND

Kinesio Taping (KT) has proved to be effective in various musculoskeletal conditions. Although its precise working mechanism has yet to be fully understood, it is believed to interact with neuromuscular function through mechanoceptor activation. No studies designed to assess the effects of KT in chronic low back pain (CLBP) patients have yet been conducted.

AIM

The aim of this study was to determine the effects of KT on pain, disability and lumbar muscle function in sufferers of CLBP, both immediately and at a one-month follow-up examination.

DESIGN

The study consisted of two phases: phase I was based on an intra-subject pre-test/post-test procedure; phase II was based on a randomized, single-blinded controlled trial.

SETTING

Outpatient facility.

POPULATION

Thirty-nine CLBP patients were enrolled.

METHODS

KT plus exercise, KT alone or exercise alone have been used for four weeks. Pain, disability and lumbar muscle function were evaluated before and after the treatment period.

RESULTS

The patients in all three groups displayed a significant reduction in pain after treatment, though only the exercise-alone group displayed reduced disability. A return to normal lumbar muscle function was observed in 28% of patients, but was not related to a reduction in pain.

CONCLUSION

When applied to CLBP patients, KT leads to pain relief and lumbar muscle function normalization shortly after its application; these effects persist over a short follow-up period.

CLINICAL REHABILITATION IMPACT

KT may represent an effective adjunct therapy in the physical rehabilitation program of CLBP patients for immediate and acute pain control.

Meta-analysis: long-term therapy with rifaximin in the management of uncomplicated diverticular disease

BACKGROUND

Diverticular disease of the colon is a common gastrointestinal disease. Although most patients remain asymptomatic for their whole life, about 20-25% present symptoms related to 'diverticular disease'. Several randomised trials verified efficacy of a poorly absorbed antibiotic, such as rifaximin-α (rifaximin), in soothing symptoms and preventing diverticulitis.

AIM

To evaluate the long-term efficacy administration of rifaximin plus fibre supplementation vs. fibre supplementation alone, on symptoms and complications, in patient with symptomatic uncomplicated diverticular disease.

METHODS

Pertinent studies were selected from the Medline, and the Cochrane Library Databases, references from published articles and reviews. Conventional meta-analysis according to DerSimonian and Laird method was used for the pooling of the results. The outcomes were 1- year complete symptom relief, and 1- year complication incidence. The rate difference (RD, with 95% CI) and the Number Needed to Treat (NNT) were used as measure of the therapeutic effect on each outcome.

RESULTS

Four prospective randomised trials including 1660 patients were selected. The pooled RD for symptom relief was 29.0% (rifaximin vs. control; 95% CI 24.5-33.6%; P<0.0001; NNT=3). The pooled RD for complication rate was -1.7% in favour of rifaximin (95% CI -3.2 to -0.1%; P=0.03; NNT=59). When considering only acute diverticulitis, the pooled RD in the treatment group was -2% (95% CI -3.4 to -0.6%; P=0.0057; NNT=50).

CONCLUSIONS

In symptomatic uncomplicated diverticular disease, treatment with rifaximin plus fibre supplementation is effective in obtaining symptom relief and preventing complications at 1 year.

Surgical access and damage extent after total hip arthroplasty influence early gait pattern and guide rehabilitation treatment

AIM

Different surgical approaches are used in total hip arthroplasty. The present study confronted two surgical techniques, analysing functional recovery in terms of activities of daily living, and ambulation using gait analysis, after a standardized rehabilitation protocol. Our hypothesis was that the increased surgical damage could modify the gait pattern and functional recovery.

METHODS

Thirty patients were randomly assigned to two homogeneous groups: Group A was treated with intermuscular minimally invasive surgery (MIS); Group B was treated with standard lateral transmuscular approach. Follow up was planned at 30 and 90 days. Instrumental evaluation using gait analysis and functional evaluation using validated scales were performed at follow up.

RESULTS

No differences could be found as for functional scales. At the first follow up, the MIS approach proved to be the most favourable: data showed a longer duration of the swing phase, an improved range of motion of the non-treated hip, a reduced adduction (all P<0.005) and a correct timing of activation of the gluteus medium muscle on the treated side. At the second evaluation, gait analysis demonstrated some benefits of the intermuscular approach (a better flexion of both hips, and a minor obliquity of the pelvis during the terminal stance), but also advantages in the transmuscular group (better hip extension).

CONCLUSION

Gait pattern after THA seems to be strictly dependent on surgical access and on the extent and location of surgical damage. It appears important to consider these elements in order to correctly manage the rehabilitation treatment after surgery.

An update on AIDS-related cholangiopathy

Both hepatic parenchymal and biliary tract diseases are common in patients with human immunodeficiency virus (HIV). In this paper, the authors focus mainly on clinical aspects of acquired immunodeficiency syndrome (AIDS)-related cholangiopathy. Although the etiology is unclear, several opportunistic infections (cytomegalovirus, Cryptosporidium and others) are suspected to cause it. Endoscopic retrograde cholangiopancreatography (ERCP) is the diagnostic gold standard and it offers a therapeutic means to provide symptomatic relief in case of papillary stenosis. The most common ERCP pattern is diffuse sclerosing cholangitis in combination with papillary stenosis. Clinically, the presentation may be variable, although right upper quadrant pain and fever accompanied by an elevated serum alkaline phosphatase (ALP) level are the most common manifestations. Jaundice is unusual suggesting that complete ductal obstruction is rare. While ERCP results and the need of sphincterotomy do not influence the prognosis, antiretroviral therapy is a protective factor and, on the contrary, high ALP level is related to a less favorable outcome. Regarding the possible pathogenic mechanisms through which HIV infection could be involved in AIDS-related cholangiopathy, in vitro experiments have shown that concurrent active HIV replication and Cryptosporidium parvum infection synergistically increase cholangiocyte apoptosis and thus jointly contribute to AIDS-related cholangiopathies.

Rhabdomyolysis due to severe hypokaliemia in a Crohn's disease patient after budesonide treatment

Patients with Crohn's disease may experience several non-digestive complications, including muscle disorders. Rabdomyolysis has rarely been reported in patients with inflammatory bowel disease, however a number of factors may cause muscular damage in this setting. We report the case of a young woman with Crohn's disease who developed a severe, symptomatic skeletal muscle damage associated with severe hypokaliemia. Reversal of the potassium levels to normal ranges led to clinical resolution. The possible causes that might have lead to hypokalemia development and subsequent rhabdomyolysis are discussed with special emphasis for the potential causative role of medical treatment, especially budesonide for which similar side effects have been previously reported. Physicians should be aware that hypokalemia is possible in the setting of Crohn's disease and muscle damage can present as a complication.

Effects of non-ionic micelles on transient chaos in an unstirred Belousov-Zhabotinsky reaction

The behaviour of the Ce(IV)-catalyzed Belousov-Zhabotinsky (BZ) system has been monitored at 20.0 degrees C in unstirred batch conditions in the absence and presence of different amounts of the non-ionic micelle-forming surfactants hexaethylene glycol monodecyl ether (C10E6) and hexaethylene glycol monotetradecyl ether (C14E6). The influence of the non-ionic surfactants on both the kinetics of the oxidation of malonic acid (MA) by Ce(IV) species and the behaviour of the BZ reaction in stirred batch conditions has also been studied over a wide surfactant concentration range. The experimental results have shown that, in unstirred batch conditions, at surfactant concentrations below the critical micelle concentration (c.m.c.) no significant change in the dynamics of the Belousov-Zhabotinsky system occurs. Beyond this critical concentration the presence of micelles forces the BZ system to undergo a chaos-->quasi-periodicity-->period-1 transition. Thus, the surfactant concentration has been considered as a bifurcation parameter for a Ruelle-Takens-Newhouse (RTN) scenario. Addition of increasing amounts of non-ionic surfactants has no significant effect on the kinetics of the reaction between MA and Ce(IV), but it influences the oscillatory parameters of the stirred BZ system. At surfactant concentrations below the c.m.c. all the oscillatory parameters are practically unaffected by the presence of surfactant, while beyond this critical value the induction period is the same as in aqueous solution but both the oscillation period and the duration of the rising portion of the oscillatory cycle decrease. In all cases, the experimental trends have been ascribed to the enhancement in the medium viscosity due to the presence of micelles.

RNAi analysis of genes expressed in the ovary of Caenorhabditis elegans

As a step towards comprehensive functional analysis of genomes, systematic gene knockout projects have been initiated in several organisms [1]. In metazoans like C. elegans, however, maternal contribution can mask the effects of gene knockouts on embryogenesis. RNA interference (RNAi) provides an alternative rapid approach to obtain loss-of-function information that can also reveal embryonic roles for the genes targeted [2,3]. We have used RNAi to analyze a random set of ovarian transcripts and have identified 81 genes with essential roles in embryogenesis. Surprisingly, none of them maps on the X chromosome. Of these 81 genes, 68 showed defects before the eight-cell stage and could be grouped into ten phenotypic classes. To archive and distribute these data we have developed a database system directly linked to the C. elegans database (Wormbase). We conclude that screening cDNA libraries by RNAi is an efficient way of obtaining in vivo function for a large group of genes. Furthermore, this approach is directly applicable to other organisms sensitive to RNAi and whose genomes have not yet been sequenced.