Ankle Inversion Proprioception Impairment in Persons with Chronic Ankle Instability Is Task-Specific.

While investigators have often compared ankle proprioception between groups with and without chronic ankle instability (CAI), findings have been inconsistent. Possibly this is because ankle proprioceptive impairment in this population is task-specific. Thus, we aimed to compare ankle inversion proprioception in individuals with and without CAI in two task conditions: (i) when standing (not challenging) and (ii) when on a step-down landing (minimally-challenging). Ankle inversion proprioception was measured in both conditions for 38 recreational sport player volunteers with CAI (n = 19) and without CAI (n = 19). We used the Active Movement Extent Discrimination Apparatus (AMEDA) for the standing condition and the Ankle Inversion Discrimination Apparatus-Landing (AIDAL) for step-down landing. From analysis of variance (ANOVA) tests, CAI and non-CAI participants performed equally well on the AMEDA when standing; but the CAI group performed significantly worse than the non-CAI group on the AIDAL step-down landing task (p = 0.03). Within the non-CAI group, the AIDAL proprioceptive scores, as area under the receiver operating characteristics curve (AUC), were significantly higher than their AMEDA AUC scores (p = 0.03), while there was no significant difference between AIDAL and AMEDA AUC scores in the CAI group. Cumberland Ankle Instability Tool CAIT scores were significantly correlated with AIDAL scores (Spearman's rho = 0.391, p = 0.015), but not with the AMEDA scores; and there was no significant correlation between the AIDAL and AMEDA scores. Thus, an ankle inversion proprioceptive deficit was evident for persons with CAI on the step-down AIDAL, and in a dose-response way, but not evident on the standing AMEDA, suggesting that ankle proprioceptive impairment is task-specific. Selected proprioceptive tests must present some minimal degree of challenge to the ankle joint in a functional task in order to differentiate CAI from non-CAI participants.

Sex differences in the relationship of hip strength and functional performance to chronic ankle instability scores.

BACKGROUND: While decreased hip abductor strength, functional performance, and self-reported instability scores have all been shown in association with CAI, any sex difference in the relationship between these indicators is unclear. This study was to determine whether sex differences are present in the relationship between these indicators in individuals with CAI. METHODS: Thirty-two women and twenty-nine men with unilateral CAI took part. Hip abductor strength and functional performance were respectively assessed using a hand-held dynamometer and the figure-8-hop test. All 61 participants scored the Cumberland Ankle Instability Tool (CAIT) for self-reported ankle instability. Independent sample t-tests and correlation analysis were conducted. RESULTS: Normalized hip abductor strength and functional performance measures for females were lower than for males. The self-reported ankle instability CAIT score, where higher values represent less instability, was significantly and positively correlated with both normalized hip abductor strength (p = 0.003) and functional performance (p = 0.001) on the affected side in females, but not in males (p = 0.361 and p = 0.192 respectively). CONCLUSIONS: Sex differences were observed in that there were significant relationships between normalized hip abductor strength, functional performance, and CAIT scores in female CAI participants, but not males, suggesting that CAI evaluation and rehabilitation strategies should be sex-specific. HIGHLIGHTS: In females with CAI, hip abductor strength and functional performance showed significant relationships with self-reported instability scores. Correspondingly, in clinical practice with individuals with CAI, evaluation criteria may be formulated according to these observed sex differences. Sex differences should be factored into the evaluation and treatment of CAI individuals. Hip strength assessment should be employed with CAI individuals. Hip strengthening and functional hopping may be recommended for the rehabilitation of CAI, especially in female patients.

Physical performance of children with longitudinal fibular deficiency (fibular hemimelia).

PURPOSE: Longitudinal fibular deficiency (LFD) is the most common congenital long bone deficiency. This study aimed to objectively assess the physical performance of children and adolescents with LFD compared with unaffected peers, and to examine trends over age for subgroups of the LFD population. METHODS: Differences between children with LFD and unaffected peers were examined with hand-held dynamometry for lower-limb muscle strength, Six-Minute Walk Test, Timed up and down stairs test, Star Excursion Balance Test, and Standing long jump. RESULTS: Thirty-nine children with LFD and 284 unaffected peers participated. Children with LFD performed at a lower level than their unaffected peers, on all measures of physical performance (mean 2.1 z-scores lower, all p < 0.01), except in long jump (p = 0.27). When comparing the performance of children with LFD to their unaffected peers across four age groups, there was a significant between-groups difference on all strength measures, and on the Six-Minute Walk distance, between children with and without LFD. These differences were smallest in young children (3-6 years) and largest in the older children (15-18 years) (all p < 0.01). Children with no lengthening surgery performed better on the Six-Minute Walk Test, covering a greater distance during the test, than those who had surgery (mean difference 83 metres, p < 0.01). There were no significant differences between children who had or had not undergone an amputation. CONCLUSIONS: Children with LFD performed at a significantly lower level than unaffected peers on all measures of physical performance other than jumping. The largest differences were in older children. This paper provides baseline functional data for future interventions in LFD. LEVEL OF EVIDENCE: Cross-sectional study.Implications for RehabilitationThis paper provides the first baseline functional data using validated objective measures on a consecutive cohort of children and adolescents with longitudinal fibular deficiency.Children with LFD performed significantly worse than their unaffected peers on all measures of physical performance other than jumping, with children falling further behind their peers as they age.Children who undergo an amputation typically have the most severe anatomical presentation and yet perform at an equivalent functional level.This paper identifies multiple modifiable impairments that represent potential opportunities for rehabilitation professionals to target with conservative treatment options to improve functional performance.

Use of electronic cigarettes in the perioperative period: A mixed-method study exploring perceptions of cardiothoracic patients in Australia.

INTRODUCTION: Electronic cigarettes (e-cigarettes) may reduce tobacco use and achieve tobacco abstinence in the perioperative period of cardiothoracic surgery for patients who smoke. However, research on patients' views on the role of e-cigarettes as a smoking cessation tool is lacking. This mixed-methods study explored perceptions on the use of e-cigarettes among current smokers and ex-smokers awaiting cardiothoracic surgery in Australia. METHODS: A cross-sectional study and semi-structured interviews were conducted with 62 patients who were diagnosed with coronary artery disease or lung cancer and were scheduled for elective cardiothoracic surgery at six metropolitan hospitals in Sydney. Data were collected on demographic characteristics, smoking history, surgical risk index, self-efficacy, interest in, perceived benefits of, and barriers to using e-cigarettes in the perioperative period. RESULTS: Current smokers reported significantly higher interest in the use of e-cigarettes (p=0.008), and perceived fewer barriers (p=0.048) and more health benefits (p=0.079), compared to ex-smokers. Current smokers considered e-cigarettes to be either a safer alternative to tobacco or a novel method for quitting. Recent ex-smokers, defined as those who quit 2-8 weeks, were a distinct group with high nicotine dependency, a long history of smoking, and multiple failed quit attempts. Compared to longer-term ex-smokers (8-52 weeks quit), recent ex-smokers were more interested in e-cigarettes (p=0.029) and considered e-cigarettes a useful aid to prevent relapse in the lead up to surgery and to manage their nicotine cravings. CONCLUSIONS: E-cigarettes may be considered a short-term novel aid and a bridge to evidence-based methods to reduce harm from continued tobacco use for some patients awaiting cardiothoracic surgery for coronary artery disease or lung cancer. This study presents reasons why patients awaiting cardiothoracic surgery may enquire about or use e-cigarettes, which will help clinicians identify those who need more consistent, sustained cessation support.

Ultrasound-based motor control training for the pelvic floor pre- and post-prostatectomy: Scoring reliability and skill acquisition.

AIM: This study documents a protocol designed to evaluate pelvic floor motor control in men with prostate cancer. It also aims to evaluate the reliability of therapists in rating motor control of pelvic floor muscles (PFMs) using real time ultrasound imaging (RUSI) video clips. We further determine predictors of acquiring motor control. METHODS: Ninety-one men diagnosed with prostate cancer attending a physiotherapy clinic for pelvic floor exercises were taught detailed pelvic floor motor control exercises by a physiotherapist using trans-abdominal RUSI for biofeedback. A new protocol to rate motor control skill acquisition was developed. Three independent physiotherapists assessed motor control skill attainment by viewing RUSI videos of the contractions. Inter-rater reliability was evaluated using intra-class correlation coefficients. Logistic regression analysis was conducted to identify predictors of successful skill attainment. Acquisition of the skill was compared between pre- and post-operative participants using an independent-group t-test. RESULTS: There was good reliability for rating the RUSI video clips (ICC 0.73 (95%CI 0.59-0.82)) for experienced therapists. Having low BMI and being seen pre-operatively predicted motor skill attainment, accounting for 46.3% of the variance. Significantly more patients trained pre-operatively acquired the skill of pelvic floor control compared with patients initially seen post-operatively (OR 11.87, 95%CI 1.4 to 99.5, p = 0.02). CONCLUSIONS: A new protocol to evaluate attainment of pelvic floor control in men with prostate cancer can be assessed reliably from RUSI images, and is most effectively delivered pre-operatively.

Pre-Operative Pelvic Floor Muscle Training--A Review.

The use of pelvic floor muscle training has been well established for the management of post-prostatectomy incontinence. In recent years, it has been hypothesized that because the severity and period of incontinence are not predictable pre-operatively, it makes sense to teach all men the new motor skill of correct pelvic floor muscle activation before surgery. This review is based on literature found through computerized and manual searches on available databases. Included were any studies that looked at the effect of adding pelvic floor muscle training pre-operatively and comparing them to the effect of not having pre-operative pelvic floor muscle exercises. Pre-operative pelvic floor muscle training was found to be effective in reducing the time to continence as well as the severity of incontinence in only four studies. Adding biofeedback or electrical stimulation was not found to change the outcomes.

The history of urologic surgery: from reeds to robotics.

Bladder function has interested man since prehistoric times. Evidence of health and well being was often measured from observation of urine. When urologic function was impaired, the extent of the ensuing pain often called for dramatic measures to obtain relief. The practice of urology has advanced substantially since the days when reeds were used to alleviate obstruction of the bladder. This article presents a brief historical overview of urology and the strides made in prostate surgery with modern technology.

Discrimination of amount of spinal flexion for movements made with and without vision after lumbar disc replacement.

Discrimination of differences between small lumbar flexion movements made when standing may differ depending on whether vision is available. Dependence on general vision during trunk movements may be increased following surgery, in which an intervertebral disc is replaced with a prosthetic disc. This study investigated whether the availability of vision changed discrimination of small differences in lumbar forward flexion movement when standing for patients with lumbar disc replacement and healthy peers. 20 volunteers without a history of back pain and 20 with disc replacement undertook a 100-trial sequence of forward flexion movements to a set of physical stops, making an absolute judgement as to the position after each movement. General (nontarget) vision during the movement was available or removed randomly trial by trial. Availability of vision did not affect discrimination of flexion movements of the lumbar spine either in normal healthy individuals or those with disc replacement.

Assessing muscle function of the male pelvic floor using real time ultrasound.

AIMS: Following surgical removal of the prostate, there may be compromise to the function of the pelvic floor muscles causing continence problems. Assessing the pelvic floor muscles of male patients can be an invasive process that causes discomfort, making it worthwhile to evaluate alternatives to the conventional method of Digital Rectal Examination (DRE). Real time ultrasound (RTUS) has been used with female patients as an alternative to internal assessments. This paper examines the reliability and validity of assessing the male pelvic floor using abdominal RTUS. METHODS: Twenty-eight men (mean age 66.2) with a history of treatment for prostate cancer were recruited to the study. They were assessed via DRE and RTUS. Findings from the procedures were correlated for evaluation of validity, and the RTUS readings were repeated by different therapists to assess reliability. RESULTS: Measurements on screen correlated moderately with DRE findings (r = 0.57, P = 0.002), and RTUS was found to have good reliability (Intra-class Correlation Coefficient = 0.90). Continent men had more movement of the bladder wall on RTUS than those who were incontinent (P = 0.043). Scar tissue and an inability to maintain a moderately full bladder were found to cause the most difficulty in getting a complete picture of pelvic floor movement. CONCLUSIONS: RTUS can be used clinically to examine male pelvic floor function, and its use would be enhanced once it has been established by DRE that a true pelvic floor contraction is occurring. RTUS can give an indication of pelvic floor function as an alternative measurement method when DRE is contraindicated.

Comparison of lumbar proprioception as measured in unrestrained standing in individuals with disc replacement, with low back pain, and without low back pain.

STUDY DESIGN: Cross-sectional laboratory study. OBJECTIVE: To determine whether individuals with spinal pain and those who have undergone spinal surgery have difficulty discriminating small movement differences using a spinal proprioception test for active flexion movements. BACKGROUND: Structures contributing to proprioception may be affected during disc replacement surgery. Postsurgical assessment of proprioceptive ability to make discriminations in the range used for maintaining upright postural stability is needed to inform postoperative rehabilitation. METHODS: Proprioceptive sensitivity to differences between lumbar spine movements of 11 degrees, 13 degrees, 15 degrees, 17 degrees, and 19 degrees of forward flexion was measured in unrestrained standing, with vision of the target obscured. Individuals after disc replacement (n=16), with disc degeneration and discogenic back pain (n=19), and without back pain (n=18) performed 50 movement trials and stated the amount of movement performed for each trial (11 degrees, 13 degrees, 15 degrees, 17 degrees, or 19 degrees). RESULTS: The pattern of discrimination scores between adjacent lumbar flexion movement pairs shown by the individuals in the discogenic back pain group differed significantly from the disc replacement and healthy control groups (P=.024), which were not significantly different from each other. Although mean discrimination scores averaged over all movement pairs did not differ significantly between the groups, participants with discogenic back pain discriminated between the 2 smallest lumbar flexion movements significantly better than those in the other 2 groups (P=.013). CONCLUSION: The greater sensitivity of the individuals with disc pain to discriminate between the 2 smallest flexion movements was interpreted as a contrast effect arising from differences between the groups in usual upright posture, with disc replacement restoring the same pattern of posture as seen for healthy controls.

Effect of anterior cruciate ligament injury and reconstruction on proprioceptive acuity of knee rotation in the transverse plane.

BACKGROUND: Studies assessing proprioceptive acuity in anterior cruciate ligament (ACL)-deficient knees have only considered proprioception for knee movements in the sagittal plane rather than in the transverse plane (ie, rotation), despite the fact that the ACL plays a critical role in knee rotational stability and that the ACL is injured almost exclusively with a rotation mechanism. Therefore a test of proprioception is needed that involves movements similar to the mechanism of injury, in this case, rotation. PURPOSE: To determine whether proprioceptive acuity in rotation changes after ACL injury and reconstruction, and to examine differences in proprioceptive acuity, range, laxity, and activity level among injured knees, contralateral knees, and healthy controls. DESIGN: Cohort study; Level of evidence, 2. METHODS: Proprioceptive acuity for active knee rotation movements, passive rotation range of motion, anterior knee laxity, and knee function were measured in 20 consecutive participants with unilateral ACL rupture and 20 matched controls. Reconstruction was performed using a single-incision technique with a 4-strand hamstring tendon autograft. Thirty participants (15 control and 15 ACL reconstructed) were retested at 3 months, and 14 with ACL reconstruction were tested at 6 months. RESULTS: A deficit was found in preoperative knee rotation proprioception compared with healthy controls (P = .031). Three months after reconstruction, there was a significant improvement (P = .049) in proprioceptive acuity, single-plane anterior laxity (P = .01), and self-reported knee function (P = .001). At 3 months after reconstruction, proprioceptive acuity of the ACL-reconstructed knee was correlated with reported activity level (r = .63; P = .021). CONCLUSION: Knee rotation proprioception is reduced in ACL-deficient participants compared with healthy controls. Three to 6 months after reconstruction, rotation proprioceptive acuity, laxity, and function were improved. While these findings are consistent with a return to previous activity level 6 months after reconstruction, the extent of graft maturation and restoration of kinematics should also inform the decision about return to sport.

Trunk stabilisation exercises reduce sternal separation in chronic sternal instability after cardiac surgery: a randomised cross-over trial.

QUESTION: Do trunk stabilisation exercises reduce sternal separation and pain, and improve the quality and control of the performance of tasks in individuals with chronic sternal instability? DESIGN: Randomised crossover study with concealed allocation and intention-to-treat analysis. PARTICIPANTS: Nine individuals with chronic sternal instability following a median sternotomy for cardiac surgery. INTERVENTION: The experimental intervention consisted of six weeks of trunk stabilisation exercises; the control intervention was no exercises. OUTCOME MEASURES: Outcomes were sternal separation measured by ultrasound in mm, pain during the performance of nine everyday tasks measured on a 100-mm visual analogue scale, and the quality and control of the performance of two tasks scored on a 100-mm visual analogue scale. RESULTS: Overall, sternal separation during the period of trunk stabilisation exercises decreased by 6.2 mm (95% CI 3.5 to 8.9) more than during the control period. Overall, pain decreased when performing everyday tasks by 14 mm (95% CI 5 to 23) more than during the control period. Overall, task performance during the period of trunk stabilisation exercises did not improve (mean difference 10 mm, 95% CI -3 to 22) more than during the control period. CONCLUSION: Trunk stabilisation exercises should be included in the rehabilitation of individuals who experience sternal instability following cardiac surgery. A larger trial is warranted to determine if stabilisation exercises are beneficial in improving the quality and control of task performance.

Relationship between pain and upper limb movement in patients with chronic sternal instability following cardiac surgery.

Physiotherapists routinely prescribe upper limb exercises for patients who have undergone a median sternotomy during cardiac surgery. It is not currently known whether upper limb exercises should be unilateral or bilateral and conducted with or without additional loading to minimise pain and further sternal separation in patients with sternal instability. Eight patients who had chronic sternal instability after cardiac surgery were included in this study. During a selected regimen of upper limb exercises, the amount of sternal separation at different vertical points on the sternum was measured by ultrasound. The amount of sternal separation was not related to type of upper limb activity, but both unilateral and unilateral loaded positions were found to be significantly associated with sternal pain (p = 0.009). In this group of patients with chronic sternal instability, bilateral upper limb movements were significantly less associated with sternal pain than unilateral movements.

Measurement of non-physiological movement in sternal instability by ultrasound.

PURPOSE: Sternal instability, a complication arising for some patients after sternotomy for cardiac surgery affects their later quality of life and cost of care. However, there are currently few guidelines for its diagnosis, quantification, and monitoring. Ultrasound equipment with associated software for calculating selected video-monitor distances provides one way of quantifying the extent of sternal separation. DESCRIPTION: This study evaluated the validity and reliability of an ultrasound measurement made by attaching the head of the unit to an extensible stand. First the procedure was tested with bony sterna, and second in the examination of the chests of 8 patients with sternal instability. EVALUATION: Reliability estimation of the ultrasound measure on bony sterna gave ICC (2, 1) values >0.99, and reliability estimates for the sternal separation measure in the patient group were ICC (2, 1) values between 0.90 and 0.93. CONCLUSIONS: Therefore gap measurements taken by ultrasound can objectively reflect the extent of bony separation occurring in a group of cardiac surgery patients experiencing sternal instability.

Physiotherapy rehabilitation of the smile after long-term facial nerve palsy using video self-modeling and implementation intentions.

OBJECTIVE: To improve smiling after long-term facial nerve palsy (FNP). Physiotherapy rehabilitation of an adapted (more symmetrical) smile was investigated in FNP subjects 1 year post-onset, using video self-modeling (video replay of only best adapted smiles) and implementation intentions (preplanning adapted smiles for specific situations). STUDY DESIGN AND SETTING: Prospective, blinded clinical trial. Facial-Nerve-Palsy Clinic. RESULTS: After video self-modeling: 1) reaction time (RT) to initiation of adapted smiles became 224 ms faster whereas RT for everyday (asymmetrical) smiles became 153 ms slower; 2) adapted smiles were completed 544 ms faster; 3) adapted smiles had higher overall quality, movement control, and symmetry ratings; and 4) Facial Disability Index scores also improved. Implementation intentions after video self-modeling ensured transfer of adapted smile to everyday situations. CONCLUSION: Following intervention the smile improved, with significant changes in availability, execution speed, and quality. SIGNIFICANCE: This study supports these rehabilitation techniques to maximize quality of smiling following FNP. EBM RATING: B-2b.

Systematic review of the treatment of post-prostatectomy incontinence.

A systematic review was conducted to critically analyze the literature on pelvic floor muscle training, biofeedback, electrical stimulation, and behavioral therapy for managing post-prostatectomy incontinence. Currently, there is a need for further study to better identify the specific components that determine the efficacy of conservative measures in the treatment of male incontinence post surgery.

Reliability of the "Sydney," "Sunnybrook," and "House Brackmann" facial grading systems to assess voluntary movement and synkinesis after facial nerve paralysis.

OBJECTIVE: To investigate the extent of within-system reliability and between-system correlation for the "Sydney" and "Sunnybrook" systems of grading facial nerve paralysis, and to examine the interobserver reliability and agreement of the "House Brackmann" grading system. STUDY DESIGN: A fixed-effects reliability study in which 6 otolaryngologists viewed videotapes of patients with facial nerve paralysis. SETTING: University and medical Centers. PATIENTS: Patients with unilateral lower motor neurone facial nerve dysfunction greater than 1 year after onset, none of whom had undergone surgical reanimation procedures. Intervention Twenty-one patients with facial nerve paralysis were videotaped while they performed a protocol of facial movements. Six otolaryngologists viewed the videotapes and scored them with the Sydney and Sunnybrook systems, and then gave a House Brackmann grade. MAIN OUTCOME MEASURE: The 3 systems of grading facial nerve paralysis were evaluated and compared with the use of intraclass correlation coefficients, Pearson's weighted kappa, and percentage exact agreement values. RESULTS: The Sydney and the Sunnybrook systems had good intrasystem reliability and high intersystem association for the assessment of voluntary movement. Grading of synkinesis was found to have low reliability both within and between systems. The House Brackmann system had substantial reliability as shown by weighted kappa but had a percentage exact agreement of 44%. CONCLUSIONS: For clinical grading of voluntary movement, there is good correlation between ratings given on the Sydney and Sunnybrook systems, and within each system there is good reliability. The assessment of synkinesis was far less reliable within, and less related between, systems. Although the reliability of the House Brackmann system was found to be high, examination of individual grades revealed some wide variation between trained observers.

A systematic review of efficacy of McKenzie therapy for spinal pain.

A systematic review of randomised clinical trials was conducted to investigate the efficacy of McKenzie therapy in the treatment of spinal pain. Databases searched included DARE, CINAHL, CENTRAL, EMBASE, MEDLINE and PEDro. To be eligible for inclusion trials had to provide treatment according to McKenzie principles and report on one of the following outcomes: pain, disability, quality of life, work status, global perceived effect, medication use, health care contacts, or recurrence. Six trials were found to be eligible, all comparing McKenzie therapy to a comparison treatment. These included NSAIDS, educational booklet, back massage and back care advice, strength training, and spinal mobilisation and general exercises. The data from five lumbar trials were pooled at short term (less than three months) and from three at intermediate (3-12 months) follow-up. At short term follow-up the McKenzie therapy provided a mean 8.6 point greater pain reduction on a 0 to 100 point scale (95% CI 3.5 to 13.7) and a 5.4 point greater reduction in disability on a 0 to 100 point scale (95% CI 2.4 to 8.4) than comparison. At intermediate follow-up, relative risk of work absence was 0.81 (0.46 to 1.44) favouring McKenzie, however the comparison treatments provided a 1.2 point greater disability reduction (95% CI -2.0 to 4.5). In the one cervical trial, McKenzie therapy provided similar benefits to an exercise program. The results of this review show that for low back pain patients McKenzie therapy does result in a greater decrease in pain and disability in the short term than other standard therapies. Making a firm conclusion on low back pain treatment effectiveness is difficult because there are insufficient data on long term effects on outcomes other than pain and disability, and no trial has yet compared McKenzie to placebo or no treatment. There are also insufficient data available on neck pain patients.

Inhibition of poly(ADP-ribosyl)ation induces DNA hypermethylation: a possible molecular mechanism.

The pattern of DNA methylation established during embryonic development is necessary for the control of gene expression and is preserved during the replicative process. DNA regions of about 1-2 kb in size, termed CpG islands and located mostly in the promoter regions of housekeeping genes, are protected from methylation, despite being about 6-10 times richer in the dinucleotide CpG than the rest of DNA. Their unmethylated state guarantees the expression of the corresponding housekeeping genes. At present, the mechanism by which CpG islands remain protected from methylation is not clear. However, some results suggest that poly(ADP-ribosyl)ation, an enzymatic process that introduces a postsynthetic modification onto chromatin proteins, might be involved. Here we show in L929 mouse fibroblast cells that inhibition of poly(ADP-ribose) polymerase(s) at different cell-cycle phases increases the mRNA and protein levels of the major maintenance DNA methyltransferase (DNMT1) in G1/S border. Increase of DNMT1 results in a premature PCNA-DNMT1 complex formation, which facilitates robust maintenance, as well as de novo DNA methylation processes during the G1/S border, which leads to abnormal hypermethylation.

The effects of phytochemical pesticides on the growth of cultured invertebrate and vertebrate cells.

A range of cultured cells of invertebrate and vertebrate origin was grown in the presence of a number of phytochemical pesticides to test the effect of the latter on cell proliferation. The main observation was that azadirachtin was a potent inhibitor of insect cell replication, with an EC50 of 1.5 x 10(10) M against Spodoptera cells and of 6.3 x 10(9) M against Aedes albopictus cells, whilst affecting mammalian cells only at high concentrations (> 10(-4) M). As expected, the other phytochemical pesticides, except for rotenone, had little effect on the growth of the cultured cells. Rotenone was highly effective in inhibiting the growth of insect cells (EC50:10(-8) M) but slightly less toxic towards mammalian cells (EC50:2 x 10(-7) M). Neem terpenoids other than azadirachtin and those very similar in structure significantly inhibited growth of the cell cultures, but to a lesser degree. The major neem seed terpenoids, nimbin and salannin, for example, inhibited insect cell growth by 23% and 15%, respectively.