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PubMed2005

High blood pressure is inversely related with the presence and extent of coronary collaterals.

Patients with hypertension have an increased case fatality during acute myocardial infarction (MI). Coronary collateral (CC) circulation has been proposed to reduce the risk of death during acute ischaemia. We determined whether and to which degree high blood pressure (BP) affects the presence and extent of CC circulation. A cross-sectional study in 237 patients (84% males), admitted for elective coronary angioplasty between January 1998 and July 2002, was conducted. Collaterals were graded with Rentrop's classification (grade 0-3). CC presence was defined as Rentrop-grade > or =1. BP was measured twice with an inflatable cuff manometer in seated position. Pulse pressure was calculated by systolic blood pressure (SBP)-diastolic blood pressure (DBP). Mean arterial pressure was calculated by DBP+1/3 x (SBP-DBP). Systolic hypertension was defined by a reading > or =140 mmHg. We used logistic regression with adjustment for putative confounders. SBP (odds ratio (OR) 0.86 per 10 mmHg; 95% confidence interval (CI) 0.73-1.00), DBP (OR 0.67 per 10 mmHg; 95% CI 0.49-0.93), mean arterial pressure (OR 0.73 per 10 mmHg; 95% CI 0.56-0.94), systolic hypertension (OR 0.49; 95% CI 0.26-0.94), and antihypertensive treatment (OR 0.53; 95% CI 0.27-1.02), each were inversely associated with the presence of CCs. Also, among patients with CCs, there was a graded, significant inverse relation between levels of SBP, levels of pulse pressure, and collateral extent. There is an inverse relationship between BP and the presence and extent of CC circulation in patients with ischaemic heart disease.

Aged↗
PubMed2006

Urotensin II is an inverse predictor of incident cardiovascular events in end-stage renal disease.

Urotensin II (UTN) is a vasoactive substance that may induce vasoconstriction or vasodilatation. Although this peptide is seen as a vasculotoxic substance, to date there is no prospective study examining the relationship between UTN and hard end points like cardiovascular (CV) events. UTN is much increased in end-stage renal disease (ESRD) and this disease may represent a useful natural model to explore the relationship between UTN and CV outcomes. In this study, we analysed the relationship between plasma UTN and incident CV events (fatal and non-fatal) in a cohort of 191 haemodialysis patients followed up for an average time of 3.6 years (range 0.07-5.8 years). Plasma UTN in haemodialysis patients (median: 6.5 ng/ml) was twice higher than in healthy subjects (median: 3.3 ng/ml). During the follow-up period, 94 patients died and 88 had incident fatal and non-fatal CV events. UTN was significantly lower in patients with incident CV events (median: 5.3 ng/ml) than in events-free patients (median: 7.1 ng/ml), and in a Kaplan-Meier analysis, high UTN was strongly and inversely associated with incident CV events (P<0.001). Multivariate Cox's regression analysis fully confirmed plasma UTN as an inverse predictor of adverse CV outcomes, and in this analysis, UTN resulted to be the third factor in rank, after age and diabetes, explaining the incidence of CV events. UTN is an inverse predictor of CV outcomes in ESRD. Our data suggest that UTN should not be necessarily seen as a vasculotoxic peptide in haemodialysis patients.

Age Factors↗
PubMed2002

The excretion of cephem antibiotics into saliva is inversely associated with their plasma protein-binding activities.

BACKGROUND: The excretion of medicated drugs into saliva may disturb the oral environment and antibiotic excretion into saliva appears to be regulated by many factors that have not been fully explored. METHODS: Excretion of four cephem antibiotics into saliva was examined in healthy volunteers and rats, using high-performance liquid chromatography, and the relationship between excretion levels and plasma protein-binding activities of the antibiotics was investigated. RESULTS: Following addition of 50 microgram/ml of each antibiotic to human plasma, protein binding rates (PBRs) of cefuzonam (CZON, molecular weight (MW): 535.58), cefotaxime (CTX, MW: 477.45), flomoxef (FMOX, MW: 518.45) and cefozopran (CZOP, MW: 551.99) were 87.8 +/- 1.2, 70.8 +/- 0.8, 36.2 +/- 0.5 and 8.3 +/- 0.3%, respectively. In rat plasma, PBRs of the four antibiotics were 94.0 +/- 0.5, 62.1 +/- 1.4, 54.0 +/- 0.8 and 6.0 +/- 0.8%, respectively. Similar PBRs were observed when the antibiotic concentration was increased to 100 and 200 microgram/ml. CZOP was most rapidly excreted into saliva and had the highest concentration in saliva among the tested antibiotics, while the plateau level of CZON was the lowest. The excreted levels of each antibiotic in saliva, when locally perfused through the rat facial artery, were inversely associated with each PBR. Similarly, the ratios of antibiotic concentration in saliva to rat plasma were almost constant for each antibiotic, revealing an inverse relationship with PBRs. CONCLUSION: These results appear to indicate that low molecular weight antibiotics are excreted into saliva through passive diffusion, inversely relating to their PBRs, and that high concentrations of antibiotics in the saliva have the potential to change the oral ecological environment.

Adult↗
PubMed2002

H1-antihistamines: inverse agonism, anti-inflammatory actions and cardiac effects.

This review addresses novel concepts of histamine H1-receptor function and attempts to relate them to the anti-inflammatory effects of H1-antihistamines. Furthermore, the molecular mechanisms underlying the cardiotoxic effects of H1-antihistamines are discussed. H1-receptors are G-protein-coupled-receptors (GPCRs), the inactive and active conformations of which coexist in equilibrium. The degree receptor activation in the absence of histamine is its 'constitutive activity'. In this two-state model, histamine acts as an agonist by combining with and stabilizing the activated conformation of the H1-receptor to shift the equilibrium towards the activated state. Drugs classified previously as antagonists act as either inverse agonists or neutral antagonists. Inverse agonists combine with and stabilize the inactive conformation of the receptor to shift the equilibrium towards the inactive state. Thus, they may down-regulate constitutive receptor activity, even in the absence of histamine. Neutral antagonists combine equally with both conformations of the receptor, do not affect basal receptor activity but do interfere with agonist binding. All H1-antihistamines examined to date are inverse agonists. As the term 'H1-receptor antagonists' is obviously erroneous, we suggest that it be replaced by 'H1-antihistamines'. The observations that H1-receptors modulate NF-kappaB activation and that there are complex interactions between GPCRs, has allowed us to postulate receptor dependent-mechanisms for some anti-inflammatory effects of H1-antihistamines, e.g. inhibition of ICAM-1 expression and the effects of bradykinin. Finally, the finding that blockade of HERG1 K+ channels is the mechanism by which some H1-antihistamines may cause cardiac arrhythmias has allowed the development of preclinical tests to predict such activity.

Animals↗
PubMed1996

Expression of metastasis suppressor gene product, nm23 protein, is not inversely correlated with the tumour progression in human malignant melanomas.

An inverse correlation between the nm23 RNA level and tumour progression of melanocytes has been reported. To elucidate whether the expression of nm23 gene product in malignant melanoma is also inversely correlated with metastatic potential, conventional prognostic parameters or the tumour suppressor protein p53, immunohisto-chemical studies using a monoclonal antibody against nm23-H1 protein were performed on 138 benign and malignant melanocytic tumours. The expression of nm23 protein was compared with that of p53 protein and conventional clinicopathological prognostic factors. The nm23 protein level in benign melanocytes and metastatic melanoma cells was also studied by Western blot analysis. No significant difference regarding the protein was observed between naevi and melanomas, either at histological or protein levels. The expression correlated with local recurrence within 1 year after surgery, level of invasion and tumour thickness, but no parallels were observed between the nm23 and p53 proteins, suggesting that gene is regulated by independent mechanisms, although located on the same chromosome. There was no inverse correlation between the nm23 protein and melanoma metastasis which suggested that the nm23 protein does not appear to be lost during melanoma metastasis.

Adult↗
PubMed1997

The extent of apoptosis is inversely associated with bcl-2 expression in premalignant and malignant breast lesions.

AIMS: In this study we investigated the extent of apoptosis in benign, premalignant and malignant breast lesions and its association with the immunohistochemical expression of bcl-2 oncoprotein. METHODS AND RESULTS: In order to detect apoptotic cells and bodies in tissue sections, the 3'-end DNA labelling method was used. Immunohistochemical staining was performed by using the avidin-biotin-peroxidase complex technique. A monoclonal antibody against bcl-2 oncoprotein was used and the specificity of the antibody was confirmed by immunoblot analysis. According to the results the extent of apoptosis, as determined by the apoptotic index, was lowest in benign ductal hyperplasias and sclerosing adenoses (0.15% and 0.07%, respectively). It was moderately elevated in atypical hyperplasias and in-situ carcinomas (0.20% and 0.40%, respectively) and highest in invasive carcinomas (0.76%). In ductal invasive carcinomas, grade I lesions showed a lower apoptotic index (0.52%) than grade II (0.72%) and grade III (1.17%) carcinomas. The apoptotic index was not significantly lower in lobular (0.82%) than in ductal invasive carcinomas (0.85%). bcl-2 immunohistochemistry was inversely related to the apoptotic index. In all cases studied the inverse association was very strong (P = 0.0004) but it was also present when only carcinomas were analysed (P = 0.01). In benign and atypical hyperplasias, bcl-2 positivity was observed in all cases, but such cases were less frequent in in-situ lesions and in invasive carcinomas. CONCLUSIONS: The results show that there is an inverse relationship between the extent of apoptosis and bcl-2 expression in breast lesions suggesting that its expression affects the regulation of apoptosis in them.

Apoptosis↗
PubMed1997

Integration host factor stimulates both FimB- and FimE-mediated site-specific DNA inversion that controls phase variation of type 1 fimbriae expression in Escherichia coli.

The site-specific DNA inversion that controls phase variation of type 1 fimbriation in E. coli is catalysed by two recombinases, FimB and FimE. Efficient inversion by either recombinase also requires the leucine-responsive regulatory protein (Lrp). In addition, FimB recombination is stimulated by the integration host factor (IHF). The effect of IHF on FimE inversion has not previously been reported. Here it is shown that IHF stimulates FimE recombination; In strain MG1655, mutants containing lesions in either the alpha (ihfA) or beta (ihfB) subunits of IHF show a marked decrease in both FimB- (100-fold) and FimE (15,000-fold)-promoted switching. IHF is shown to bind with high affinity to sites both adjacent to (site I) and within (site II) the fim invertible element. Furthermore, mutations in site I or site II that lower the affinity of IHF binding In vitro were found to lower the frequency of FimE and/ or FimB recombination in vivo. Although site I and site II mutations in combination have an effect on FimB-promoted switching comparable to that of IHF knockout mutations (100-fold), the cis site mutations have a much less marked effect (100-fold) on FimE-promoted switching.

Amino Acid Sequence↗
PubMed2000

Effects of local transcription and H-NS on inversion of the fim switch of Escherichia coli.

The fim switch of Escherichia coli is responsible for phase-variable expression of type 1 fimbriae. Switching in the ON-to-OFF and OFF-to-ON directions is promoted by the FimB recombinase, while the FimE recombinase directs switching predominantly in the ON-to-OFF direction. The effects of local promoter activity and the H-NS nucleoid-associated protein on inversion of the switch were assessed. In contrast to FimB-mediated inversion, inversion of the switch by the FimE recombinase was unaffected by the H-NS status of the cell. Transcription towards the switch from within a translationally inactivated fimE gene was found to bias the switch strongly in the OFF direction, creating a FimE+-like phenotype in the absence of the FimE protein. This biasing was H-NS dependent and was also contingent on transcription from within the switch. These data show that local transcription and a nucleoid-associated protein both contribute to the modulation of a site-specific recombination event on the bacterial chromosome.

Alleles↗
PubMed2000

Protective immunity in human Bancroftian filariasis: inverse relationship between antibodies to microfilarial sheath and circulating filarial antigens.

The existence and the nature of protective immunity in human filariasis continues to be a subject of intense debate. While there is no broad consensus on functional immunity against larval and adult stage parasites, anti-microfilarial immunity has been demonstrated to be mediated by antibodies to the microfilarial sheath. In the present study, circulating filarial antigens (CFA), a marker of active filarial infection in human Bancroftian filariasis, was found to be inversely associated with antibodies to microfilarial sheath in a cohort of 411 subjects representing all categories of filariasis across the clinical spectrum of the disease. Approximately 80% of humans of all age groups (5-65 years) were found to have either CFA or anti-sheath antibodies. The inverse relationship observed between these two parameters was found to be independent of the clinical manifestation; both symptomatic and asymptomatic cases were found to display similar inverse association between CFA and anti-sheath antibodies. The prevalence of anti-sheath antibodies in the paediatric group was found to be very high as compared to adults; 78% of children below the age of 10 years tested positive for anti-sheath antibodies although the mf rate and CFA rate were only 4.5% and 22.7%, respectively, in this age group, indicating that developing larvae or juvenile adult stage parasites could have been the source of antigenic stimulus for induction of antibodies to the microfilarial sheath.

Adolescent↗
PubMed1998

Role of the cerebellum in reaching movements in humans. I. Distributed inverse dynamics control.

This study focuses on the role of the motor cortex, the spinal cord and the cerebellum in the dynamics stage of the control of arm movement. Currently, two classes of models have been proposed for the neural control of movements, namely the virtual trajectory control hypothesis and the acquisition of internal models of the motor apparatus hypothesis. In the present study, we expand the virtual trajectory model to whole arm reaching movements. This expanded model accurately reproduced slow movements, but faster reaching movements deviated significantly from the planned trajectories, indicating that for fast movements, this model was not sufficient. These results led us to propose a new distributed functional model consistent with behavioural, anatomical and neurophysiological data, which takes into account arm muscles, spinal cord, motor cortex and cerebellum and is consistent with the view that the central nervous system acquires a distributed inverse dynamics model of the arm. Previous studies indicated that the cerebellum compensates for the interaction forces that arise during reaching movements. We show here how the cerebellum may increase the accuracy of reaching movements by compensating for the interaction torques by learning a portion of an inverse dynamics model that refines a basic inverse model in the motor cortex and spinal cord.

Arm↗
PubMed1997

Immunomagnetic separation for enhanced flagellar antigen phase inversion in salmonella.

Immunomagnetic separation (IMS) was used to reduce delays in serotyping caused by slow flagellar phase inversion of diphasic salmonellas. Some 375 strains of 11 salmonella serotypes were examined using IMS. The mean time for successful flagellar phase inversion was reduced from 4.3 (range 1-18) d to 1.0 (range 1-3) d using the IMS method, and in a further experiment phase inversion was achieved within 8 h in 112 of a further 117 strains representing four salmonella serotypes.

Animals↗
PubMed2002

Treatment of inverse psoriasis with the 308 nm excimer laser.

BACKGROUND: The treatment of inverse psoriasis can be both challenging and frustrating. Conventional topical and systemic treatments can be limited in terms of efficacy, acceptability and safety. The 308 nm excimer laser has been shown to be effective in the treatment of psoriatic plaques. METHODS: A patient with chronic inverse psoriasis was treated with 308 nm excimer laser using a 3.5 cm spot, a dosage of 2 minimal erythema doses and a pulse width of 30 ns. RESULTS: Complete clearance of the psoriatic lesions was obtained after 3 weeks of treatment. Remission duration was at least 6 months. CONCLUSION: The 308 nm excimer laser is safe and effective for the treatment of inverse psoriasis. Treatments are well tolerated with minimal side effects.

Adult↗
PubMed2002

Patella inversion method for exposure in revision total knee arthroplasty.

Satisfactory performance of revision total knee arthroplasty (TKA) requires adequate exposure. This article shows the patella inversion method of exposure in a large consecutive series of revision TKAs.Between 1987 and 1999, 420 revision TKAs were performed. Exposure was facilitated by the patella inversion method. No attempt was made to evert the patella. This technique of exposure was used in 95% (397 of 420) of patients. There were no episodes of patellar tendon avulsion in this series. Multiple exposure options are available in revision TKA. Extensile techniques violate the extensor mechanism. For most patients, these methods were unnecessary. The patella inversion method afforded adequate exposure in most patients without violating the extensor mechanism.

Arthroplasty, Replacement, Knee↗
PubMed1996

An investigation of neural tissue involvement in ankle inversion sprains.

SUMMARY. The slump test was used to investigate the effect of ankle inversion sprain on neurodynamic function in 18 subjects. The sensory response and restriction in range of knee extension in the slump test were assessed. Three different foot and ankle positions were used-neutral, dorsiflexion (DF) and plantarflexion with inversion (PFI). Results indicated that although there was a significantly greater lack of knee extension on the injured side compared to the non-injured side in all three foot and ankle positions, knee extension was most restricted in the PFI position, which is considered to bias the common peroneal tract. The slump test in PFI produced symptoms in the lateral aspect of the lower leg and ankle extending slightly anteriorly and posteriorly and into the dorsum of the foot. This distribution corresponds to that of the superficial peroneal nerve. The slump test in neutral and DF produced areas of response similar to each other, which included the posterior aspect of the knee, thigh and calf. The release of cervical flexion resulted in a significant reduction in symptoms in each test. These results may indicate altered neurodynamic function following ankle inversion sprain, and have implications for assessment and treatment of subjects with ankle sprain. Copyright 1996 Harcourt Publishers Ltd.

Journal Article↗
PubMed1996

[Flow contrast behavior in fast MR angiography with an ECG-triggered, slice-selective inversion recovery turbo-FLASH technique].

PURPOSE: To optimise and evaluate fast "inflow"-based contrast-prepared gradient-echo magnetic resonance angiography (MRA) of blood vessels with pulsatile flow. MATERIAL AND METHOD: We used a standard 2-D Turbo-FLASH sequence with an acquisition time of 0.9 s and a slice-selective hyperbolic secant inversion (SSIR) pulse for contrast preparation. Trigger delay and inversion time were systematically varied. RESULTS: Abdominal blood vessels of volunteers showed high signal intensity compared to stationary tissue without pulsatile artifacts. However, depending on cardiac cycle and inversion time, venous vessels in particular exhibited a periodic signal drop by maximum 70% of the peak value. Using optimised parameters SSIR turbo-FLASH images of patients could be obtained with high flow contrast between normal and pathological structures. CONCLUSION: With ECG triggering SSIR Turbo-FLASH MRA enables fast imaging of pulsatile vessels with optimised flow contrast.

Abdomen↗
PubMed1981

Arthrography, talar tilt and surgical findings after inversion trauma of the ankle.

Both inversion stress examination under general anesthesia and arthrography are sensitive indicators of lateral ankle ligament pathology (91%, 96% resp.). Arthrography is significantly superior to inversion stress examination done under local anesthesia (96%, 70% resp.). Peroneus tendon sheath filling is always pathological, but although this does not always indicate calcaneo-fibular ligament rupture, such rupture cannot be excluded in its absence. Talar tilt difference cannot be correlated with the extent of ligamentous rupture and therefore inversion stress examination, while providing valuable additional information, must be regarded as a secondary technique to ankle arthrography.

Ankle Injuries↗
PubMed2001

The efficacy of adjusting the ankle in the treatment of subacute and chronic grade I and grade II ankle inversion sprains.

OBJECTIVE: The purpose of this study was to determine the efficacy of adjusting the ankle in the treatment of subacute and chronic grade I and grade II ankle inversion sprains. DESIGN: A single-blind, comparative, controlled pilot study. SETTING: Technikon Natal Chiropractic Day Clinic. PARTICIPANTS: Thirty patients with subacute and chronic grade I and grade II ankle inversion sprains. Patients were recruited from the public; they responded to advertisements placed in newspapers and on notice boards around the campus and local sports clubs. INTERVENTION: Each of the 15 patients in the treatment group received the ankle mortise separation adjustment. Each of the 15 patients in the placebo group received 5 minutes of detuned ultrasound treatment. Each participant received a maximum of 8 treatment sessions spread over a period of 4 weeks. MAIN OUTCOME MEASURE: Patients were evaluated at the first treatment, at the final treatment, and at a 1-month follow-up consultation. Subjective scores were obtained by means of the short-form McGill Pain Questionnaire and the Numerical Pain Rating Scale 101. Objective measurements were obtained from goniometer readings measuring ankle dorsiflexion range of motion and algometer readings measuring pain threshold over the ankle lateral ligaments. A functional evaluation of ankle function was also used. RESULTS: Although both groups showed improvement, statistically significant differences in favor of the adjustment group were noted with respect to reduction in pain, increased ankle range of motion, and ankle function. CONCLUSIONS: This study appears to indicate that the mortise separation adjustment may be superior to detuned ultrasound therapy in the management of subacute and chronic grade I and grade II inversion ankle sprains.

Adolescent↗
PubMed1994

Trade-off between achromatic colour and perceived illumination as revealed by the use of pseudoscopic inversion of apparent depth.

The albedo hypothesis was tested under apparent transformations of perceived illumination and achromatic colour induced by pseudoscopic inversion of apparent depth. Looking through a pseudoscope made a cone attached to a vertical white screen look like a conical hole in the screen. This in turn caused the shadow which the now 'invisible' cone cast on the screen to change its appearance and to look like a darkly pigmented area. The darkness of the shadow before the pseudoscopic reversal and greyness of colour afterwards were measured by means of psychophysical scales for darkness and greyness set by the bisection method. Contrast of the shaded area was varied from 0.17 to 0.96 in 7 steps, the mean illuminance of the screen having been maintained at 40 1x. Although the albedo hypothesis in its classical form was not confirmed, it was found that darkness of shadow varied linearly in inverse proportion to greyness of colour within the entire contrast range. This is in agreement with the hypothesis that achromatic colour and perceived illumination are inversely proportional to each other while the retinal illumination is constant.

Color Perception↗