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The current document commissioned by the Society for Cardiovascular Angiography and Interventions (SCAI) and endorsed by the American College of Cardiology, the American Heart Association, and Heart Rhythm Society represents a comprehensive update to the 2012 and 2016 consensus documents on patient-centered best practices in the cardiac catheterization laboratory. Comprising updates to staffing and credentialing, as well as evidence-based updates to the pre-, intra-, and post-procedural logistics, clinical standards and patient flow, the document also includes an expanded section on CCL governance, administration, and approach to quality metrics. This update also acknowledges the collaboration with various specialties, including discussion of the heart team approach to management, and working with electrophysiology colleagues in particular. It is hoped that this document will be utilized by hospitals, health systems, as well as regulatory bodies involved in assuring and maintaining quality, safety, efficiency, and cost-effectiveness of patient throughput in this high volume area.

Urgent transcatheter aortic valve implantation (TAVI) is a feasible option for aortic stenosis (AS) patients with decompensated heart failure (HF) and cardiogenic shock (CS) as compared to the more traditional urgent balloon aortic valvuloplasty (BAV).We conducted a retrospective analysis to compare risk and cause of readmission in these two high-risk groups.Nationwide Readmission Database (NRD) 2011-2014 was retrospectively analyzed to identify patients with AS having either urgent TAVI or urgent BAV using appropriate ICD-9 codes. Propensity scores were used to match patients with urgent TAVI as compared to patients with urgent BAV. Statistical analysis was performed using the Stata 15.1 software.We identified a weighted sample of 6,670 patients with urgent BAV and 6,964 patients with urgent TAVI. The all-cause 30- and 90-day readmission was lower in the urgent TAVI group compared to urgent BAV (15.4 vs. 22.5%, (aHR): 0.92 [0.90-0.95] p .001). 30-day readmission due to CV cause and HF was also lower in the urgent TAVI group (aHR, 0.93: p .001 and aHR, 0.98: p = .040, respectively). The 30-day gastrointestinal (GI) bleed readmission rate was three times higher in urgent TAVI group (aHR, 3.00:95% CI (1.23-7.33), p = .016), but was not statistically significant at 90-days. Cardiac causes of readmission were the predominant cause of readmission in both groups, but more pronounced in urgent BAV group (60.3 vs. 40.5%, p .001).Urgent TAVI appears beneficial in patients with AS and decompensated HF or CS driven by roughly 10 and 25% reductions in overall readmissions at 30 and 90 days, and marked reductions in reintervention, although offset partially by higher risk of readmission due to GI bleeding at 30 days.

Background Cardiac implantable electronic devices (CIED) are sometimes required after alcohol septal ablation (ASA) for hypertrophic cardiomyopathy (HCM). The primary objectives of this study were to characterize the incidence, timing, and predictors of CIED placement after ASA for HCM. Methods Patients were identified from the 2010-2015 Nationwide Readmissions Databases. Incidence, timing and independent predictors of CIED placement, as well as 30-day readmission rates were examined. Results There were 1296 patients (national estimate = 2864) with HCM who underwent ASA. CIED were implanted in 322 (25% overall; 14% permanent pacemaker, 11% implantable cardioverter defibrillator) during the index hospitalization. Of these, 21%, 23%, 21%, and 18% occurred on postprocedure day 0, 1, 2, and 3, respectively. Only 17 (1.3%) patients underwent CIED implantation between discharge and 30-day follow up. Independent predictors of index hospitalization CIED implantation included older age, diabetes, heart failure, nonelective index hospital admission and hospitalization at a privately owned hospital. Nonelective 30-day readmission rates among those who did and did not undergo CIED placement during their index hospitalization, were 6.8% and 7.9%, respectively (p = .53); median time to readmission was also similar between groups. Conclusions One in four HCM patients undergoing ASA underwent CIED implantation during their index hospitalization; nearly 2/3rd during the first 48 h postprocedure. Private hospital ownership independently predicted CIED placement. More data are needed to better understand the unexpectedly high rates of CIED placement, earlier than anticipated timing of implantation and differential rates by hospital ownership.

The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is highly infectious, carries significant morbidity and mortality, and has rapidly resulted in strained health care system and hospital resources. In addition to patient-related care concerns in infected individuals, focus must also relate to diminishing community spread, protection of staff, case selection, and concentration of resources. The current document based on available data and consensus opinion addresses appropriate catheterization laboratory preparedness for treating these patients, including procedure-room readiness to minimize external contamination, safe donning and doffing of personal protective equipment (PPE) to eliminate risk to staff, and staffing algorithms to minimize exposure and maximize team availability. Case selection and management of both emergent and urgent procedures are discussed in detail, including procedures that may be safely deferred or performed bedside.

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The aim of this article is to discuss the poor outcomes associated with critical limb ischemia (CLI) and the required knowledge needed for optimal care. There is an opportunity for the Society for Cardiovascular Angiography and Interventions (SCAI) to assist interventional cardiologists in enhancing CLI care through creation of training standards and development of educational content.

Background Diabetes patients undergoing percutaneous coronary intervention (PCI) have more complications than nondiabetes patients, including increased long-term mortality. Use of bivalirudin versus heparin and glycoprotein IIb/IIIa inhibitors (GPI) in diabetes patients undergoing PCI and its effect on long-term mortality were evaluated in few randomized trials, but with conflicting results. Methods We searched the literature for randomized controlled trials that compared heparin and GPI therapy with bivalirudin in diabetes patients undergoing PCI. The incidence of major adverse cardiovascular events (MACE), death from any cause, myocardial infarction (MI), urgent revascularization, major and minor bleeding (at 30 days), as well as all-cause mortality at 1 year were included, and meta-analysis was performed. Results A total of 5,137 patients with diabetes were included in four randomized trials. At 30 days, bivalirudin, compared with heparin and GPI, caused less major bleeding (odds ratio (OR), 0.68; 95% confidence interval (CI), 0.52–0.89; P = 0.005) and less minor bleeding (OR, 0.48; 95% CI, 0.41–0.57; P

The Appropriate Use Criteria for Coronary Revascularization (AUC) were created in 2009 [1,2] and updated in 2012 [3] through a rigorous process and then endorsed by major cardiovascular societies. The AUC were developed from a limited set of carefully defined clinical scenarios; they were not envisioned as covering every clinical situation, but rather, descriptive of common ones. The AUC have become widely accepted as one component of decision making, along with published clinical guidelines, physician experience, and patient preference. Regrettably, they have also come to be seen as an instrument for directing insurance coverage policy. While the original AUC document [1,2] noted “it is hoped that payors would use these criteria as the basis for the development of rational payment management strategies to ensure that their members receive necessary, beneficial, and costeffective cardiovascular care,” denial of coverage in individual cases based on the AUC category was not an intended purpose. In addition, the 2012 update [3] explicitly states that some inappropriate indications should be reimbursed and that the uncertain rating does not justify denial of payment. Policymakers and payors must be good stewards of the insurance system, and are increasingly challenged to find innovative ways to curb expenditures. Thus, it is tempting for them to view the AUC as a professionally mandated tool for “cost-cutting” [4]. SCAI and its members recognize the essential need for prudent cost management but are very concerned with this unanticipated and detrimental approach to coverage determinations. This SCAI position statement addresses our members’ apprehension that the application of AUC by many payors without consideration of other features of the patient’s medical condition is far beyond the intent of the AUC, and has the potential for significant unintended consequences for patients and hospitals. Accordingly, this position statement outlines SCAI’s recommendations regarding the use of AUC in making coverage determinations for percutaneous coronary intervention (PCI) procedures. SCAI and its members have several concerns. First, although the AUC may be useful in helping to guide insurance coverage, the AUC classification should not be the solitary reason used to deny coverage. Such unjustifiable application of AUC might be harmful to patients, and could be contrary to shared decision

Objectives To evaluate the periprocedural characteristics and outcomes of patients supported with Impella 2.5 prior to percutaneous coronary intervention (pre-PCI) versus those who received it after PCI (post-PCI) in the setting of cardiogenic shock (CS) complicating an acute myocardial infarction (AMI). Background Early mechanical circulatory support may improve outcome in the setting of CS complicating an AMI. However, the optimal timing to initiate hemodynamic support has not been well characterized. Methods Data from 154 consecutive patients who underwent PCI and Impella 2.5 support from 38 US hospitals participating in the USpella Registry were included in our study. The primary end-point was survival to discharge. Secondary end-points included assessment of patients’ hemodynamics and in-hospital complications. A multivariate regression model was used to identify independent predictors for mortality. Results Both groups were comparable except for diabetes (P = 0.02), peripheral vascular disease (P = 0.008), chronic obstructive pulmonary disease (P = 0.05), and prior stroke (P = 0.04), all of which were more prevalent in the pre-PCI group. Patients in the pre-PCI group had more lesions (P = 0.006) and vessels (P = 0.01) treated. These patients had also significantly better survival to discharge compared to patients in the post-PCI group (65.1% vs.40.7%, P = 0.003). Survival remained favorable for the pre-PCI group after adjusting for potential confounding variables. Initiation of support prior to PCI with Impella 2.5 was an independent predictor of in-hospital survival (Odds ratio 0.37, 95% confidence interval: 0.17–0.79, P = 0.01) in multivariate analysis. The incidence of in-hospital complications included in the secondary end-point was similar between the 2 groups. Conclusions The results of our study suggest that early initiation of hemodynamic support prior to PCI with Impella 2.5 is associated with more complete revascularization and improved survival in the setting of refractory CS complicating an AMI.

Objective To study rotational atherectomy (RA) outcomes in patients undergoing high-risk PCI randomized to receive hemodynamic support using either IABP or Impella 2.5 in the PROTECT II trial. Background RA of heavily calcified lesions is often necessary for complex PCI but can be associated with slow-flow, hypotension, and higher risk of periprocedural MI. Methods We compared baseline, angiographic, procedural characteristics, and outcomes of patients treated with and without RA. We examined also RA technique and outcomes. Results RA was used in 52 of 448 patients (32 with Impella vs 20 with IABP, P = 0.08). RA patients were older (72 vs. 67 yo, P = 0.0009), more likely to have prior CABG (48 vs. 32%, P = 0.017), higher STS (8.1 vs. 5.7, P = 0.012) and higher SYNTAX scores (37 vs. 29, P

Chronic kidney disease (CKD) is a known prognostic indicator of poor outcomes following percutaneous coronary intervention (PCI) for coronary artery disease. However, it is unclear whether other predictors of mortality differ among patients with varying degrees of renal impairment. Thus, we aimed to identify determinants of in-hospital mortality which are specific to patients with preserved renal function, moderate CKD, or end stage renal disease (ESRD) on dialysis, undergoing PCI.The study population included 25,018 patients who underwent PCI between January 1, 2004, and December 31, 2007, at four New York State hospitals. The primary endpoint of the study was in-hospital mortality.A total of 474 (1.9%) patients had ESRD on dialysis, 6,596 (26.4%) had moderate CKD (GFR60 ml/min/1.73 m(2) ), and 17,948 (71.7%) had preserved renal function (GFR60 ml/min/1.73 m(2) ). Patients with ESRD and moderate CKD were older, more often male, and had higher rates of prior coronary revascularization, peripheral vascular disease, congestive heart failure, prior stroke, and diabetes than those with preserved function. All-cause in-hospital mortality rates were significantly higher in patients with ESRD and moderate CKD compared to patients with GFR60 ml/min/1.73 m(2) (2.1% and 1.3%, respectively vs. 0.3%, p0.001). In multivariable analysis, ESRD (OR: 3.68, 95% CI 1.62-8.36) and moderate CKD (OR: 2.92, 95% CI 1.91-4.46) were independently associated with higher rates of in-hospital mortality. Independent predictors of mortality were markedly distinct in each group and included female gender and myocardial infarction within the past 72 hr in the ESRD group, versus left ventricular ejection fraction, peripheral vascular disease, congestive heart failure, emergency PCI, and absence of prior PCI in the moderate CKD group and age, prior bypass graft surgery, congestive heart failure, emergency PCI, and absence of prior myocardial infarction in patients with preserved renal function.Patients with moderate CKD or ESRD undergoing PCI have an approximately threefold increase in the risk of in-hospital mortality compared with patients with preserved renal function, with radically different mortality predictors existing for varying levels of renal function.

Objectives: We report on the real-world, multicenter experience of the Impella 2.5 circulatory support system during high-risk PCI, a subset of the larger USpella Registry. Background: Standard of care for most patients with compromised ventricular function with multivessel or high-risk coronary lesions has been coronary artery bypass grafting. In poor operative candidates, high-risk PCI is increasingly considered, despite an increased risk for periprocedural hemodynamic compromise. Methods: 175 consecutive patients who underwent high-risk PCI with prophylactic support of the Impella 2.5 were evaluated. The primary safety endpoint was the incidence of major adverse cardiac events (MACE) at 30 days. Secondary endpoints included safety and efficacy related to the device and patient outcomes, including survival at 12 months. Results: Overall angiographic revascularization was successful in 99% of patients and in 90% of those with multivessel revascularization, resulting in a reduction of the mean SYNTAX score post-PCI from 36 ± 15 to 18 ± 15 (P < 0.0001) and an improvement of the ejection fraction (from 31 ± 15% to 36 ± 14%, P < 0.0001). In 51% of patients, the functional status improved by one or more NYHA class (P < 0.001). At 30-day follow-up, the rate of MACE was 8%, and survival was 96%, 91%, and 88% at 30 days, 6 months, and 12 months, respectively. Conclusions: The use of Impella 2.5 in high-risk PCI appeared feasible and safe in the real-world setting. The utilization of the Impella 2.5 was successful, resulting in favorable short- and midterm angiographic, procedural and clinical outcomes. © 2012 Wiley Periodicals, Inc.

GaPO4 nanoparticles having hexagonal structure with different amounts of Eu3+ ions were prepared at 130°C based on precipitation method in glycerol medium. The interaction between GaPO4 nanoparticles and Eu3+ ions has been investigated using Eu3+ luminescence and 31P magic angle spinning nuclear magnetic resonance (MAS NMR) techniques. Based on these studies, it is established that Eu3+ ions up to 2.5 at.% replace the protons of the hydroxyl groups attached on Ga3+ ions present on the surface of the nanoparticles and above 2.5 at.%, a separate EuPO4 phase is formed. The anisotropy parameters derived from the side band intensities of the 31P MAS NMR patterns from these samples confirmed the surface ion exchange at low Eu3+ concentration (2.5 at.%) and EuPO4 phase formation at high Eu3+ concentration (5 at.% and more). The increase in anisotropy at high Eu3+ contents has been attributed to the presence of paramagnetic EuPO4 phase.

Background: Timely and successful treatment of myocardial infarction (MI) requires accurate recognition by the patient of the signs and symptoms. As patients who have undergone percutaneous coronary intervention (PCI) remain at risk for cardiac events, it is important that they have a basic understanding of their cardiac status. Methods: We surveyed 80 consecutive patients following elective PCI using a simple multiple-choice questionnaire. Type of stent (bare metal or drug-eluting), how they perceive the procedure would affect their cardiovascular health, their perceived risk of a future MI, and whether they recalled specific education on how to recognize symptoms of an MI were queried. Results: 45% (n = 36) of patients were unaware of stent type. 10% stated PCI was performed to relieve symptoms of angina, 30% (n = 24) stated it would prevent MI, 56.3% (n = 45) stated that it would both prevent MI and reduce symptoms of angina, while 3.8% stated it would do neither. 86.3% (n = 69) stated they remained at risk for MI despite the procedure. However, 42.5% (n = 34) of patients did not perceive to have received specific education on the signs and symptoms of MI during their hospital stay. Conclusions: Patient understanding of stent type, expected cardiovascular outcomes, and recognition of MI post-PCI appears low in the real-world setting. A systematic approach to post-PCI education should be incorporated into routine care, in order to capitalize on the educational opportunity afforded by this high risk population. (J Interven Cardiol 2011;24:144–148)

Relative efficacy of two substrates commonly employed for procuring scallop spat is described. Monofilament gillnetting was superior to flexible polyethylene insofar as collecting greater numbers of sea scallops was concerned. Overlapping in sheet polyethylene resulted in rapid substrate saturation thus reducing substrate surface for larval attachment.

The open-loop optimal control of a linear, shift-invariant, singularly perturbed discrete system is considered. The resulting two-point boundary value problem (TPBVP) is cast in the singularly perturbed form. It is found that in the process of degeneration, the original system loses some of the initial and final conditions. A singular perturbation method is developed to obtain approximate solutions composed of outer series, initial correction series and final correction series to recover the lost boundary conditions. The method is given for zeroth, first and any order of approximation. An example is provided to illustrate the proposed method.

Objective: To investigate if women with recurrent urinary tract infection (UTI) warrant cystoscopy to exclude an abnormality of the lower urinary tract. This is particularly relevant given that non-invasive imaging has often been performed to exclude abnormality. Our further aims were to correlate imaging and risk factors with cystoscopic findings to determine their predictive value in finding pathology. Patients and methods: A database of women undergoing cystoscopy with recurrent UTI has been maintained at our institution for 10 years. We retrospectively examined this and patient records for patient demographics, and investigative and operative data. Results: A total of 118 patients (mean 55 years) having recurrent UTI (mean 4.7 infections/year) were available. There were nine patients (8%) with significant abnormalities at cystoscopy: urethral stricture (six), bladder calculus (one), bladder diverticulum (one) and colovesical fistula (one). The negative predictive value (NPV) of imaging was 99% and significant (P 0.05). The positive predictive value was low for imaging and risk factors in predicting cystoscopy findings. Conclusions: In our study, 8% of women had significant abnormalities detected during cystoscopy with most over 50 years. Women without risk factors for recurrent UTI and with normal imaging could have a cystoscopy omitted. Younger women are less likely to have pathology and this must be factored into decisions to perform cystoscopy.

1. Epilepsy is one of the major neurological disorders of the brain, affecting approximately 0.5-1.0% of the population worldwide. Various neurotransmitter abnormalities, especially of GABA and glutamate, have been reported to play a key role in the pathophysiology of epilepsy. 2. Cyclo-oxygenase (COX) is the rate-limiting enzyme in the production of prostaglandins and, as such, is a key target for many anti-inflammatory drugs. Cyclo-oxygenase has been reported to play a significant role in neurodegeneration. Recent studies have reported that COX plays a significant role in the pathophysiology of epilepsy. 3. The aim of the present study was to explore the possible role of COX and the effect of COX inhibitors in epilepsy. 4. Kindling is a chronic model of epilepsy. In the present study, kindling was induced in mice by chronic administration of a subconvulsive dose of pentylenetetrazole (PTZ; 40 mg/kg) on every other day for a period of 15 days. Naproxen was administered daily 45 min before PTZ or vehicle. The kindling score was recorded after PTZ administration. Seizure severity was measured according to a prevalidated scoring scale. Biochemical estimations were performed immediately after recording behavioural parameters on the 16th day of PTZ treatment. 5. Chronic treatment with PTZ significantly induced kindling in mice. Pretreatment with the non-selective COX inhibitor naproxen (7 and 14 mg/kg, i.p.) showed significant protection against PTZ-induced kindling in mice. Biochemical analysis revealed that chronic treatment with PTZ significantly increased lipid peroxidation and nitrite levels (NO levels), but decreased reduced glutathione (GSH) levels in brain homogenates. 6. In conclusion, the results of the present study strongly suggest that COX plays an important role in the pathophysiology of PTZ-induced kindling in mice and that COX inhibitors could be a useful neuroprotective strategy for the treatment of epilepsy.

Purpose: To study effect of scan length on magnitude of imaging dose deposition in Varian kV CBCT for head & neck and pelvis CBCT. Methods: To study effect of scan length we measured imaging dose at depth of 8 cm for head and neck Cone Beam Computed Tomography (CBCT) acquisition (X ray beam energy is used 100kV and 200 degree of gantry rotation) and at 16 cm depth for pelvis CBCT acquisition (X ray beam energy used is 125 kV and 360 degree of gantry rotation) in specially designed phantom. We used farmer chamber which was calibrated in kV X ray range for measurements .Dose was measured with default field size, and reducing field size along y direction to 10 cm and 5 cm. Results: As the energy of the beam decreases the scattered radiation increases and this contributes significantly to the dose deposited in the patient. By reducing the scan length to 10 Cm from default 20.6 cm we found a dose reduction of 14% for head and neck CBCT protocol and a reduction of 26% for pelvis CBCT protocol. Similarly for a scan length of 5cm compared to default the dose reduction in head and neck CBCT protocol is 36% while in the pelvis CBCT protocol the dose reduction is 50%. Conclusion: By limiting the scan length we can control the scatter radiation generated and hence the dose to the patient. However the variation in dose reduction for same length used in two protocols is because of the scan geometry. The pelvis CBCT protocol uses a full rotation and head and neck CBCT protocol uses partial rotation.

In an earlier study, we reported the ability of quercetin to reverse the development of morphine tolerance and dependence in mice. In the present study we have attempted to explore the possible involvement of nitric oxide (NO) system in quercetin reversal of morphine tolerance and dependence in mice. Co-administration of L-N(G)-nitro arginine methyl ester (L-NAME) or quercetin with morphine during the induction phase (days 1-9) delayed the development of tolerance to the antinociceptive action of morphine and also reversed naloxone precipitated withdrawal jumps. L-Arginine administration during the induction phase enhanced the development of tolerance to the antinociceptive effect of morphine but had no effect on the naloxone-precipitated withdrawal jumps. During the expression phase (day 10) acute administration of quercetin or L-NAME reversed, whereas L-arginine facilitated naloxone- precipitated withdrawal jumps in morphine-tolerant mice, but none of these drugs affected the nociceptive threshold in morphine-tolerant mice. Further, co-administration of quercetin or L-NAME with L-arginine during the induction phase antagonized the latter effects on the development of morphine tolerance. Also, prior administration of quercetin or L-NAME reversed the L-arginine potentiation of nalaxone-precipitated withdrawal jumps in morphine-tolerant mice. The results of the present study suggest that quercetin reversal of morphine tolerance and dependence may involve its ability to suppress nitric oxide synthase (NOS) activity.

Quercetin, a bioflavonoid (25 and 50 mg/kg), when chronically administered for 9 days, failed to produce any significant change in tail flick latency as compared to control mice. However, repeated administration of quercetin (25 and 50 mg/kg) for 9 days attenuated the development of tolerance to the analgesic effect of morphine (10 mg/kg). Quercetin (25 and 50 mg/kg) also suppressed naloxone (2 mg/kg)-precipitated withdrawal jumps on day 10 in morphine-tolerant mice. Pretreatment of mice with quercetin (10–50, ip) significantly reversed the morphine (5 mg/kg)-induced delay in gastric transit, whereas a higher dose of quercetin (100 mg/kg) did not have any significant effect on morphine-induced delay in gastric transit. Quercetin per se had no effect on gastric transit. In conclusion, the results of the present study suggest potential use of quercetin in alleviating the adverse effects of opioid treatment. Drug Dev. Res. 57:167–172, 2002. © 2003 Wiley-Liss, Inc.

1. Tardive dyskinesia (TD), a syndrome of potentially irreversible, involuntary hyperkinetic disorder occurring in 20 - 40% of the patient population undergoing chronic neuroleptic treatment is a major limitation of neuroleptic therapy. 2. Oxidative stress and products of lipid peroxidation are implicated in the pathophysiology of various neurological disorders including tardive dyskinesia. 3. Chronic treatment with neuroleptics leads to the development of abnormal oral movements in rats known as vacuous chewing movements (VCMs). Vacuous chewing movements in rats are widely accepted as an animal model of tardive dyskinesia. 4. All the antipsychotics were administered i.p. once daily for 21 days, whereas carvedilol (also i.p.) was administered twice daily. Rats chronically treated with haloperidol (1.0 mg kg(-1)) or chlorpromazine (5 mg kg(-1)) but not clozapine (2 mg kg(-1)) significantly developed vacuous chewing movements and tongue protrusions. Carvedilol dose dependently (0.5 - 2 mg kg(-1)) reduced the haloperidol or chlorpromazine-induced vacuous chewing movements and tongue protrusions. 5. Biochemical analysis revealed that chronic haloperidol or chlorpromazine but not clozapine treatment significantly induced lipid peroxidation and decreased the glutathione (GSH) levels in the forebrains of rats. Chronic haloperidol or chlorpromazine but not clozapine treated rats showed decreased forebrain levels of antioxidant defence enzymes, superoxide dismutase (SOD) and catalase. 6. Co-administration of carvedilol (0.5-2 mg kg(-1)) significantly reduced the lipid peroxidation and restored the decreased glutathione levels by chronic haloperidol or chlorpromazine treatment. Co-administration of carvedilol (1-2 mg kg(-1)) significantly reversed the haloperidol or chlorpromazine-induced decrease in forebrain SOD and catalase levels in rats. However, lower dose of carvedilol (0.5 mg kg(-1)) failed to reverse chronic haloperidol or chlorpromazine-induced decrease in forebrain SOD and catalase levels. 7. The major findings of the present study suggest that oxidative stress might play a significant role in neuroleptic-induced orofacial dyskinesia. In conclusion, carvedilol could be a useful drug for the treatment of neuroleptic-induced orofacial dyskinesia.

The degrees of human lactoferrin (HLf) and bovine lactoferrin (BLf) binding in 169 Escherichia coli strains isolated from human intestinal infections, and in an additional 68 strains isolated from healthy individuals, were examined in a 125I-labelled protein binding assay. The binding was expressed as a percentage calculated from the total labelled ligand added to bacteria. The HLf and BLf binding to E. coli was in the range 3.7 to 73.4% and 4.8 to 61.6%, respectively. Enterotoxigenic strains demonstrated a significantly higher HLf binding (median = 19%) than enteropathogenic, enteroinvasive, enterohaemorrhagic strains or normal intestinal E. coli isolates (medians 6 to 9). Enteropathogenic strains belonging to serotypes O44 and O127 demonstrated significantly higher HLf binding compared to O26, O55, O111, O119 and O126. No significant differences in the degree of HLf or BLf binding were found between aerobactin-producing and non-producing strains. The interaction was further characterized in a high Lf-binding EPEC strain, E34663 (serotype O127). The binding was stable in the pH range 4.0 to 7.5, did not dissociate in the presence of 2M NaCl or 2M urea, and reached saturation within two h. Unlabelled HLf and BLf displaced the 125I-HLf binding to E34663 in a dose-dependent manner. Apo- and iron-saturated forms of Lf demonstrated similar binding to E34663. Among various unlabelled subepithelial matrix proteins and carbohydrates tested (in 10(4)-fold excess) only fibronectin and fibrinogen caused a moderate inhibition of 125I-HLf binding. According to Scatchard plot analysis, 5,400 HLf-binding sites/cell, with an affinity constant (Ka) of 1.4 x 10(-7) M, were estimated in strain E34663. These data establish the presence of a specific Lf-binding mechanism in E. coli.

A lactoferrin-binding protein with an estimated molecular mass of 57 kDa was identified in the cell envelope of Prevotella intermedia by gel electrophoresis and Western-blot analysis. Peroxidase-labeled bovine lactoferrin and human lactoferrin showed similar specific binding to this protein. Whole cells of P. intermedia were also examined for interactions with 5 125I-labeled plasma and subepithelial matrix proteins. A high degree of binding was found with fibronectin, collagen type I and type IV and laminin, whereas a moderate interaction was detected with fibrinogen. The ability of bovine lactoferrin to affect the interactions of the above proteins with P. intermedia was examined. In the presence of unlabeled bovine lactoferrin, a dose-dependent inhibition of binding was observed with all 5 proteins tested. Unlabeled bovine lactoferrin also dissociated the bacterial complexes with these proteins. The complexes with laminin or collagen type I were more effectively dissociated than fibronectin or fibrinogen, whereas the interaction with collagen type IV was affected to a lesser extent. A strain-dependent variation in the effect of bovine lactoferrin was observed. These data establish the presence of a specific lactoferrin-binding protein in the cell envelope of P. intermedia. The ability of lactoferrin to inhibit the binding of some plasma and subepithelial matrix proteins to P. intermedia could be a protective mechanism against the establishment of this pathogen in the periodontal pocket.

Objectives To investigate the efficacy of phenytoin in relation to total and free serum levels in patients with severe pre-eclampsia and eclampsia. Design Prospective descriptive study. Setting Labour Ward, King Edward VIII Hospital, Durban, South Africa. Tertiary referral centre serving an underprivileged community. Subjects Eleven patients admitted with a hypertensive crisis. Four patients had eclampsia and 7 had impending eclampsia. Main outcome measures Free and total phenytoin levels; efficacy of phenytoin as an anticonvulsant and side-effects of therapy. Results Although total phenytoin levels were within the therapeutic range, free phenytoin levels were abnormally high in all patients. Three patients (2 with eclampsia and 1 with imminent eclampsia) each had a seizure after phenytoin treatment had been initiated. Conclusion Neither total nor free phenytoin levels were good predictors of seizure control. It is postulated that the poor performance of phenytoin as an anticonvulsant in severe eclampsia may relate to inadequate distribution of the drug to the brain as a result of cerebral oedema and poor cerebral perfusion rather than paradoxical seizure activity associated with high free phenytoin levels.

The closed-loop optimal control of a linear, time-invariant, singularly perturbed discrete system is considered. The resulting matrix Riccati difference equation is formulated in the singularly perturbed structure. It is observed that the degeneration affects some of the final conditions of the Riccati equation. A singular perturbation method is developed to obtain approximate solutions in terms of an outer series and a final correction series. The outer series takes advantage of the order reduction associated with degeneration and the correction series takes care of the affected final conditions. Two examples are given to illustrate the proposed method.

A study of probability distribution function and spectrum of the Airborne Total Intensity Map for an area of 3000 Squ. miles covered by the Bundelkhand granite in India has revealed a close correlation between the Gaussian or non-Gaussian nature of distribution and the shape of unite value contour on the spectrum plot. Further studies of radial spectrum plots suggest that the surface magnetic sources are mainly responsible for the non-Gaussian character of the distribution function and as well as for irregular spectrum shape. The histogram of depth values for magnetic sources obtained from radial spectrum plots show three horizons, namely (i) surface (ii) 410 m(1400′) and (iii) 1000 m (3400′). Based on these informations blocks with ferromagnetic composition at the surface can be identified from those which are non magnetic at the surface.

An efficient method of computing spectrum and cross-spectrum of large scale aero-magnetic field (or of any other two-dimensional field) has been developed and programmed for a digital computer. The method uses fast Fourier transform techniques. Briefly, the method is as follows: a digitized aeromagnetic map is divided into a number of rectangular blocks. Fourier transforms of these blocks are computed using a two-dimensional fast Fourier transform method. Finally, the amplitude of the Fourier transforms is averaged to give the desired spectrum. Computation of cross-spectrum follows the same lines. In fact, the same programme may be used to a compute the spectrum as well as cross-spectrum. The method has a number of computational advantages, in particular it reduces greatly computational time and storage requirements. The programme has been tested on synthetic data as well as on real aeromagnetic data. It took less than 30 seconds on an IBM 360/50 computer to compute the spectrum of an aeromagnetic map covering an area of approximately 4500 square miles.

A point source or a dipole source of electric current, placed on a randomly layered semi-infinite medium, produces an inhomogeneous random potential field on the surface. The variance of the random potential, normalized with reference to the normal field (that is, a field due to a point source or a dipole source on a homogeneous medium), falls off inversely as the distance from the source. The conductivity of the layers is assumed to vary randomly about a mean value (unity) such that the variations can be represented by a zero mean homogeneous random function. Further the variations are assumed to be small compared to the mean so that the first order perturbation is adequate. The analysis shows that the dipole field is more sensitive than the single pole field to the conductivity variations.