Homocystinuria: Challenges in diagnosis and management

Two patients with homocystinuria are discussed. Both patients presented with behavioural abnormalities and deficits in attention - symptoms that are frequently encountered in paediatric office practice. In both cases, the diagnosis of homocystinuria was not made at initial presentation. Subtle but definite phenotypic features eventually provided the first indication of homocystinuria between the ages of five to seven years. Laboratory screening confirmed homocystine in the urine, and elevated methionine and homocysteine plasma levels in both patients. Patients with inborn errors of metabolism such as homocystinuria are treated first by family physicians and paediatricians. Without a high index of suspicion, physicians can easily overlook a diagnosis of homocystinuria. The management of patients with homocystinuria continues to pose a challenge to physicians and care givers.

In situ observation of size-scale effects on the mechanical properties of ZnO nanowires

In this investigation, the size-scale in mechanical properties of individual [0001] ZnO nanowires and the correlation with atomic-scale arrangements were explored via in situ high-resolution transmission electron microscopy (TEM) equipped with atomic force microscopy (AFM) and nanoindentation (NI) systems. The Young's modulus was determined to be size-scale-dependent for nanowires with diameter, d, in the range of 40 nm ≤ d ≤ 110 nm, and reached the maximum of ∼ 249 GPa for d = 40 nm. However, this phenomenon was not observed for nanowires in the range of 200 nm ≤ d ≤ 400 nm, where an average constant Young's modulus of ∼ 147.3 GPa was detected, close to the modulus value of bulk ZnO. A size-scale dependence in the failure of nanowires was also observed. The thick ZnO nanowires (d ≥ 200 nm) were brittle, while the thin nanowires (d ≤ 110 nm) were highly flexible. The diameter effect and enhanced Young's modulus observed in thin ZnO nanowires are due to the combined effects of surface relaxation and long-range interactions present in ionic crystals, which leads to much stiffer surfaces than bulk wires. The brittle failure in thicker ZnO wires was initiated from the outermost layer, where the maximum tensile stress operates and propagates along the (0001) planes. After a number of loading and unloading cycles, the highly compressed region of the thinner nanowires was transformed from a crystalline to an amorphous phase, and the region near the neutral zone was converted into a mixture of disordered atomic planes and bent lattice fringes as revealed by high-resolution images.

Efficacy, safety and tolerability of duloxetine in idiopathic trigeminal neuralgia

Trigeminal neuralgia (TN) is the most common type of neuralgia affecting facial region and is considered to be one of the most painful conditions. Treatment is often unsatisfactory. Newer treatment modalities are therefore being tried. Duloxetine is FDA approved drug for painful diabetic neuropathy and has been used in painful symptoms of depression as well. Safety and efficacy of duloxetine was evaluated in patients with trigeminal neuralgia; another chronically painful condition, in an open label manner. A total of 15 patients who fulfilled the diagnostic criteria of International Headache Society for Trigeminal Neuralgia were administered duloxetine 40 mg daily. The efficacy of the drug was evaluated by face scale and Likert's numerical scale. Statistically significant pain relief was reported in 9 out of 15 patients of trigeminal neuralgia. The pain relief was reported as early as in one week and was maintained for 16 weeks. The drug was well tolerated and side-effects reported were mild and reversible. No adverse drug reaction requiring hospitalisation or drug discontinuation was reported in the present study. Duloxetine showed statistically significant pain relief in trigeminal neuralgia. Double-blind, placebo-controlled studies are needed to confirm findings at a large scale.

Postoperative pain after cholecystectomy: Conventional laparoscopy versus single-incision laparoscopic surgery

BACKGROUND

This study was undertaken to compare the postoperative pain after cholecystectomy done by single-incision laparoscopic surgery (SILS) versus conventional four-port laparoscopy [conventional laparoscopic surgery (CLS)]. SILS is a feasible and a promising method for cholecystectomy. It is possible to do this procedure without the use of special equipments. While there are cosmetic advantages to SILS, it is not clear whether or not the pain is also reduced.

METHODS

Patients undergoing cholecystectomy for symptomatic gallstones were offered the choice of the two methods and the first 100 consecutive patients from each group were included in this observational study. Only conventional instruments were used to keep the cost of surgery comparable. Pain scores were checked 8 hours after the surgery using visual analogue score. Student's t test was done to check the statistical significance.

RESULTS

We observed no significant difference in the pain score between the CLS and SILS (2.78 versus 2.62). The operative time (OT) was significantly lower in the CLS group (28 versus 67 minutes). Comparing the OTs of the first 50 patients undergoing SILS with the second 50 patients showed a significantly lower OT (79 versus 54 minutes). We also compared the pain score between these three groups. The second half of SILS group had a significantly lower pain score compared to the first half (2.58 versus 2.84). This group also had a lower pain score compared to conventional laparoscopy group but the difference was not statistically significant (2.58 versus 2.78).

CONCLUSION

Although there was no significant difference in the overall postoperative pain as OT decreases with surgeon's experience in single-incision laparoscopic cholecystectomy, postoperative pain at 8 hours appears to favour this method over conventional laparoscopic cholecystectomy.

Hemizygous deletions on chromosome 1p21.3 involving the DPYD gene in individuals with autism spectrum disorder

We describe the identification and clinical presentation of four individuals from three unrelated families with hemizygous deletions involving the DPYD gene at chromosome 1p21.3. DPYD encodes dihydropyrimidine dehydrogenase, which is the initial and rate-limiting enzyme in the catabolism of pyrimidine bases. All four individuals described met diagnostic criteria for autism spectrum disorder with severe speech delay. Patient 1's deletion was originally reported in 2008, and more detailed clinical information is provided. Subsequently, this male individual was found to have a missense mutation in the X-linked PTCHD1 autism susceptibility gene, which may also contribute to the phenotype. Patients 2 and 3 are siblings with a novel deletion encompassing the DPYD gene. In their mother, the genomic region deleted from chromosome 1p21.3 was inserted into chromosome 10. A fourth proband had a novel 10-kb intragenic deletion of exon 6 of the DPYD gene detected on a higher resolution microarray. Our study suggests that hemizygous deletions involving the DPYD locus present with variable phenotypes which can include speech delay and autistic features, and may also be influenced by additional mutations in other genes, issues which need to be considered in genetic counseling.

Multi detector computed tomography (MDCT) evaluation of small bowel obstruction: pictorial review

Small bowel obstruction (SBO) is one of the most perplexing clinical situations encountered by a surgeon in the emergency room. The decision to operate or not depends upon many factors including the probable cause and chances of bowel strangulation/ischemia. The clinical, biochemical and radiological features help the surgeon in making this decision. Plain X-rays have been the mainstay in the radiological diagnosis of SBO and its complications. In the last 20 years, CT scan has ushered in a revolution in establishing the diagnosis of SBO, its causes and complications earlier than the traditional methods and has helped in reducing morbidity and mortality. Here, we have summarised the role of multidetector CT scan in diagnosing various aspects of SBO.

Phase-flip transition in coupled electrochemical cells

Time delay is introduced in the coupling between a pair of electrochemical cells. As coupling parameters are varied, the anodic current in the two cells oscillate in synchrony in regimes of periodic as well as chaotic dynamics. When the time delay is varied a phase-flip transition is observed: the relative phase between the synchronized oscillations changes abruptly by pi . This is accompanied by an experimentally measurable discontinuous change in the frequency of the synchronized oscillators.

Suppression of quadrupolar order on Si doping in YbRu(2)(Ge(1 - x)Si(x))(2)

We have investigated the magnetic properties of polycrystalline Y bRu(2)(Ge(1 - x)Si(x))(2) samples using magnetic susceptibility, electrical resistivity, and specific heat measurements. All the results indicate that the Yb ions in Y bRu(2)(Ge(1 - x)Si(x))(2) are in a stable trivalent state. The antiferromagnetic ordering shifts to lower temperature with increasing Si concentration (x). The weak Kondo-like resistivity minimum observed in the resistivity data for x = 0 shifts toward lower temperature with an increase in the Si content and finally disappears. The most dramatic observation is the complete suppression of the quadrupolar ordering in Y bRu(2)Ge(2) (T(Q) = 10 K) even for 2% Si doping.

A whole genome scan to map QTL for milk production traits and somatic cell score in Canadian Holstein bulls

The detection and mapping of genetic markers linked to quantitative trait loci (QTL) can be utilized to enhance genetic improvement of livestock populations. With the completion of the bovine genome sequence assembly, single nucleotide polymorphisms (SNP) assays spanning the whole bovine genome and research work on large scale identification, validation and analysis of genotypic variation in cattle has become possible. The objective of the present study was to perform a whole genome scan to identify and map QTL affecting milk production traits and somatic cell scores using linkage disequilibrium (LD) regression and 1536 SNP markers. Three and 18 SNP were found to be associated with only milk yield (MY) at a genome and chromosome wise significance (p < 0.05) level respectively. Among the 21 significant SNP, 16 were in a region reported to have QTL for MY in other dairy cattle populations and while the rest five were new QTL finding. Four SNP out of 21 are significant for the milk production traits (MY, fat yield, protein yield (PY), and milk contents) in the present study. Six and nine SNP were associated with PY at a genome and chromosome wise significant (p < 0.05) level respectively. Three and 17 SNP were found to be associated with FY at a genome and chromosome wise significant (p < 0.05) level. Five and seven SNP were mapped with somatic cell score at a genome and chromosome wise significant (p < 0.05) level respectively. The results of this study have revealed QTL for MY, PY, protein percentage, FY, fat percentage, somatic cell score and persistency of milk in the Canadian dairy cattle population. The chromosome regions identified in this study should be further investigated to potentially identify the causative mutations underlying the QTL.

Segmental coronary endothelial dysfunction in patients with minimal atherosclerosis is associated with necrotic core plaques

BACKGROUND/OBJECTIVE

Endothelial dysfunction and atherosclerosis are systemic disorders, but are often characterised by segmental involvement and complications. A potential mechanism for local involvement early in the disease process may be related to plaque composition. This study was designed to test the hypothesis that in patients with minimal coronary atherosclerosis, coronary artery segments with abnormal endothelial function have specific plaque characteristics.

METHODS

Intravascular ultrasound (IVUS) images were obtained from 30 patients who underwent coronary endothelial function assessment. Spectral analysis of the IVUS radiofrequency data was used for assessment of plaque composition. IVUS findings of the coronary sections were compared according to the corresponding endothelial response to acetylcholine.

RESULTS

Sections with a decrease epicardial coronary arterial diameter in response to acetylcholine had smaller baseline lumen (7.5 (2.4) mm(2) vs 8.8 (3.3) mm(2), p = 0.006) but larger plaque burden (37.1% (9.4%) vs 31% (7%), p = 0.003) than sections with normal endothelial response. Sections with endothelial dysfunction had larger necrotic core plaques: 0.13 (0.03-0.33) mm(2) vs 0.0 (0.0-0.07), p<0.001 and more dense calcium: 0.03 (IQR 0.0-0.13) mm(2) vs 0.0 (0.0-0.10) mm(2), p<0.01), than those with normal endothelial response. Only necrotic core area was associated with endothelial dysfunction (p<0.001) after adjusting for other measures.

CONCLUSIONS

This study suggests that local coronary endothelial dysfunction in patients with minimal coronary atherosclerosis is associated with plaque characteristics that are typical of vulnerable plaques.

Stress hormone and circulating biomarker profile of apical ballooning syndrome (Takotsubo cardiomyopathy): insights into the clinical significance of B-type natriuretic peptide and troponin levels

OBJECTIVE

To evaluate the stress neurohumoral and cardiac biomarker profile of patients with apical ballooning syndrome (ABS).

METHODS

Plasma-free metanephrines, B-type natriuretic peptide (BNP), high sensitivity C-reactive protein (hsCRP) and troponin T, as well as 24-hour urine catecholamines, metanephrines and free cortisol were measured in 19 ABS and 10 ST-elevation myocardial infarction (STEMI) patients.

RESULTS

An antecedent stressful event was identified in 15 ABS patients. There were no differences in plasma normetanephrine (median 0.64 (IQ range 0.43-0.97) nmol/l vs 0.53 (0.32-0.77) nmol/l, p = 0.44), metanephrine (0.10 (0.10-0.22) nmol/l vs 0.16 (0.10-0.38) nmol/l, p = 0.29), or cortisol levels (16.0 (7.3-44.0) microg/dl vs 13.0 (10.5-23.5) microg/dl, p = 0.95) between ABS and STEMI patients. The 24-hour urine metanephrines, catecholamines and cortisol levels were normal in the majority of ABS patients. Troponin T levels were lower (0.62 (0.18-0.84) ng/ml vs 3.80 (2.04-6.57) ng/ml, p<0.001), but BNP levels were higher in ABS compared with STEMI (944 (650-2022) pg/ml vs 206 (140-669) pg/ml, p = 0.009). HsCRP was similarly elevated in the two groups (11.0 (5.1-110.8) mg/l and 24.3 (8.1-88.6) mg/l, p = 0.78).

CONCLUSIONS

Catecholamine and cortisol levels were not elevated in our cohort of ABS, suggesting that routine measurement of these stress hormones is unlikely to be of diagnostic value in practice. In contrast to STEMI, ABS is characterised by a greater elevation in BNP and less myonecrosis.

Activity of lenalidomide in a phase II trial for T-cell lymphoma: Report on the first 24 cases

8524

Background: Novel therapies are needed to improve outcomes in T-cell lymphomas. We report the interim results of a prospective multicenter trial evaluating lenalidomide in T-cell lymphomas. Methods: Patients with relapsed and refractory T-cell lymphomas other than mycosis fungoides were prescribed oral lenalidomide (25mg daily) on days 1 to 21 of each 28 day cycle, with standardized dose reductions for toxicity. Treatment continued until disease progression, death or unacceptable toxicity. The primary endpoint was overall response rate, and secondary endpoints were complete and partial response rates, progression-free and overall survival (PFS, OS), and safety. The two-stage design allows for up to 40 patients. Results: At the time of this interim analysis, 24 patients were enrolled in this study and 23 were evaluable for response. The median age was 65 years. ECOG PS was 0–1 (n=15), 2 (n=7), 3 (n=2). The histology was peripheral T-cell unspecified (PTCL-u, n=10), angioimmunoblastic (n=7), anaplastic large cell (n=5), enteropathic T-cell (n=1) and hepatosplenic gamma/delta (n=1). Median number of prior therapies was 1 (range, 0–4), and three had prior autologous stem cell transplant. Four patients were previously untreated and not candidates for combination chemotherapy. Median time from completion of prior therapy to the start of lenalidomide was 8 months (range, 1–48 months). The overall response rate was 7/23 (30%); all were partial responses. Two patients had stable disease (SD) for ≥3 cycles. Responses were seen in anaplastic, angioimmunoblastic, and PTCL-u histologies. Median PFS was 96 days (range, 8–696 days). Median OS was 241 days (range, 8–696+ days). Among the 9 patients with SD or better, median PFS was 168 days and median OS has not yet been reached with 241–696 days of follow-up. The most common grade 4 adverse event was thrombocytopenia (33.3%). The most common grade 3 adverse events were neutropenia (20.8%), febrile neutropenia (16.7%), and pain NOS (16.7%). Conclusions: In relapsed and refractory T-cell lymphomas, oral lenalidomide monotherapy has clinical activity and toxicity is consistent with the known profile of lenalidomide. Further study of lenalidomide in these diseases is warranted.

[Table: see text]

YbNiB(4): a Kondo lattice with low-dimensional antiferromagnetic fluctuations

We have grown single crystals of YbNiB(4) using a Ni(60)B(40) flux and determined the magnetic properties of this compound by means of magnetic susceptibility, specific heat and electrical resistivity measurement. Yb ions in YbNiB(4) are in a trivalent state and present a transition from a paramagnetic state to an antiferromagnetic (AF) state at T(N1) = 5.4 K and a further transition towards a second AF state at T(N2) = 4.0 K. Kondo type behavior in the resistivity and an enhanced Sommerfeld coefficient γ = 100 mJ mol(-1) K(-2) provide evidence for a significant Kondo interaction. A broad maximum in χ(T) at around 8 K, well above T(N1), suggests low-dimensional antiferromagnetic correlations. Both mechanisms lead to strong fluctuation in an extended temperature range above T(N1), up to the characteristic energy of this system, which was estimated to be T(4f) = 16 K from an analysis of the entropy.

Aeromonas caviae septicemia in immunocompetent gastrointestinal carriers

Aeromonas caviae strains have been isolated from blood and stool cultures of three immunocompetent patients, residents of Northern India, who presented with community acquired septicemia without any recent history of diarrhea. Cell culture infectivity test performed on Hep-2 cells have shown substantial degree of invasiveness in the isolated strains. This case unleashes a possibility of asymptomatic gastrointestinal carriage of such strains of A. caviae in a very large population of India, as several areas of India have very high rates of Aeromonas induced acute diarrhea/gastroenteritis (up to 13%). It needs to be appraised further in India as well as other countries having high rates of Aeromonas induced acute diarrhea/gastroenteritis.

Study of the physical properties of a mesogenic mixture showing induced smectic A(d) phase by refractive index, density and x-ray diffraction measurements

The binary mixture of 4-n-pentyl phenyl 4-n'-hexyloxy benzoate (ME6O.5) and p-cyanophenyl trans-4-pentyl cyclohexane carboxylate (CPPCC) shows the presence of an induced smectic A(d) phase in a certain concentration range 0.03<x(CPPCC)<0.6. The results of the differential scanning calorimetry (DSC), refractive indices, densities and x-ray diffraction measurements are reported here. In general, the change in birefringence is continuous at the smectic A(d) to nematic phase transition for mixtures with x>0.33, whereas there is a discontinuity in these values for mixtures with x<0.33, consistent with the density and transition entropy measurements done on this system. The orientational order parameter, measured from x-ray diffraction studies, are somewhat smaller than those obtained from refractive index measurement in the induced smectic phase for all the mixtures. In the smectic phase, the OOP values initially increases with molar concentration up to x = 0.24 and then decreases showing a broad minima around x = 0.4. The variation of layer thickness in the induced smectic phase with composition has been explained by assuming the formation of homo- and heterodimers. We conclude that the possible packing of molecules in the induced smectic A(d) phase stabilizes the layers but increases the orientational free volume, consistent with the lower orientational order parameter.

A bacterial interference strategy for prevention of UTI in persons practicing intermittent catheterization

Study Design

Non-randomized pilot trial

Objectives

Determine whether Escherichia coli 83972-coated urinary catheters in persons with spinal cord injury (SCI) practicing an intermittent catheterization program (ICP) could (1) achieve bladder colonization with this benign organism, and (2) decrease the rate of symptomatic urinary tract infection (UTI).

Setting

Outpatient SCI clinic in a Veterans Affairs hospital (USA)

Methods

Participants had neurogenic bladders secondary to SCI, were practicing ICP, had experienced at least 1 UTI, and had documented bacteruria within the past year. All subjects received a urinary catheter that had been pre-inoculated with E. coli 83972. The catheter was left in place for 3 days then removed. Subjects were followed with urine cultures and telephone calls weekly for 28 days and then monthly until E. coli 83972 was lost from the urine. Outcome measures were (1) the rate of successful bladder colonization, defined as the detection (≥10² cfu/ml) of E. coli 83972 in urine cultures for > 3 days after catheter removal and (2) the rate of symptomatic UTI while colonized with E. coli 83972.

Results

Thirteen subjects underwent 19 insertions of study catheters. Eight subjects (62%) became successfully colonized for > 3 days after catheter removal. In these 8 subjects, the rate of UTI while colonized was 0.77 per patient-year, in comparison to the rate of 2.27 UTI per patient-year prior to enrollment.

Conclusions

E. coli 83972-coated urinary catheters are a viable means to achieve bladder colonization with this potentially protective strain in persons practicing ICP.

Correlation of Disc Damage Likelihood Scale, visual field, and Heidelberg Retina Tomograph II in patients with glaucoma

PURPOSE

To correlate the analysis of the optic nerve head (ONH) obtained with Disc Damage Likelihood Scale (DDLS), Heidelberg Retina Tomograph II (HRT II), and visual field (VF) parameters (Aulhorn scale, mean deviation [MD], and pattern standard deviation [PSD]) in patients with glaucoma.

METHODS

Sixty-five eyes were evaluated using the DDLS classification. Fifty-seven eyes had stable primary open-angle glaucoma (POAG) and eight eyes were normal (control group). Classification of the ONH was performed using the HRT II, with Moorfields Regression Analysis (MRA) and Cup Shape Measure (CSM) indexes. The VF was examined by Full Threshold test (30-2) using the Humphrey Field Analyzer (HFA) perimeter and evaluated by three

METHODS

Aulhorn's scale of 0 to 6, and two global indices, MD and PSD.

RESULTS

The amount of ONH damage as estimated by the DDLS correlated well with topographic damage determined by HRT II (r=0.923 with MRA and r=0.807 with CSM) and with visual field loss as measured by the MD (r=-0.792) and PSD (r=0.718) of the HFA and Aulhorn field staging system (r=0.849).

CONCLUSIONS

This study shows that evaluation of the ONH using the DDLS provides information that correlates well with VF and with data obtained from HRT II.

A whole-genome scan to map quantitative trait loci for conformation and functional traits in Canadian Holstein bulls

Genetic improvement of livestock populations can be achieved through detection and mapping of genetic markers linked to quantitative trait loci (QTL). With the completion of the bovine genome sequence assembly, single nucleotide polymorphism (SNP) assays spanning the whole bovine genome and research work on large-scale identification, validation, and analysis of genotypic variation in cattle has become possible. A total of 462 Canadian Holstein Bulls were used to test the association between SNP and QTL. Single locus linkage disequilibrium regression model was implemented to perform a whole genome scan to identify and map QTL affecting conformation and functional traits. One thousand five hundred thirty-six SNP markers from introns and exons of potential QTL regions for economically important traits across the bovine genome were selected for association analysis. A total of 45 and 151 SNP were found to be associated with 17 conformation and functional traits at a genome- and chromosome-wise significance level, respectively. Among the 196 significant SNP, 169 of them are newly detected in this study, whereas 27 of them have been reported in previous literature and 161 of these were located in genes and are worth further investigating to potentially identify the causative mutations underlying the QTL. The single locus linkage disequilibrium regression method using SNP marker genotypes has proven to be a successful methodology for detecting and mapping QTL in dairy cattle populations.

Linkage disequilibrium and signatures of selection on chromosomes 19 and 29 in beef and dairy cattle

The objective of this study was to quantify the extent of linkage disequilibrium (LD) on bovine chromosomes 19 and 29 and to study the pattern of selection signatures in beef and dairy breeds (Angus and Holstein) of Bos taurus. The extent of LD was estimated for 370 and 186 single nucleotide polymorphism markers on BTA19 and 29 respectively using the square of the correlation coefficient (r(2)) among alleles at pairs of loci. A comparison of the extent of LD found that the decline of LD followed a similar pattern in both breeds. We observed long-range LD and found that LD dissipates to background levels at a locus separation of about 20 Mb on both chromosomes. Along each chromosome, patterns of LD were variable in both breeds. We find that a minimum of 30 000 informative and evenly spaced markers would be required for whole-genome association studies in cattle. In addition, we have identified chromosomal regions that show some evidence of selection for economically important traits in Angus and Holstein cattle. The results of this study are of importance for the design and application of association studies.

Carotid intimomedial thickness in type 2 diabetic patients and its correlation with coronary risk factors

AIMS

To compare the carotid intimal-medial thickness in type 2 diabetics with and without coronary artery disease (CAD), and to correlate the intimal-medial thickness (IMT) with known coronary risk factors.

METHODS

One hundred and eleven patients of type 2 diabetes were recruited for the study. History and physical examination were recorded. Laboratory investigations included fasting and 2-hour post-prandial blood sugar, blood urea, serum creatinine, lipid profile, glycated haemoglobin, and microalbuminuria. Ultrasonographic scanning of the carotid arteries was performed to measure the carotid IMT. For identification of cases of silent ischaemia, treadmill test (TMT) was performed.

RESULTS

The study group was divided into a non-CAD group (n=40), and a CAD group (n=71). The mean carotid IMT of the group as a whole, was 0.840 +/- 0.2 mm. The mean carotid IMT was significantly higher (p<0.0001) in type 2 diabetics with CAD (both overt and silent) than in those without CAD. In diabetics with CAD, the systolic blood pressure, diastolic blood pressure and triglycerides were found to be predictors of high mean carotid IMT. On subgroup analysis of the cases with silent ischaemia, the variables affecting carotid IMT were serum creatinine, total cholesterol, microalbuminuria/proteinuria, serum triglyceride levels, and diastolic blood pressure.

CONCLUSION

A high carotid IMT is a surrogate and reliable marker of higher risk of CAD amongst type 2 diabetic patients, even in those without overt CAD. The study underlines the utility of carotid IMT as a simple, non-invasive, safe, and cheap screening test for the assessment of risk/prognosis of CAD in type 2 diabetics. We have also demonstrated the usefulness of measuring IMT, as a means to detect silent CAD among type 2 diabetics.

Effect of zinc supplementation on respiratory tract infections in children with cystic fibrosis

Zinc (Zn) has significant anti-oxidant and anti-inflammatory activity. Zn deficiency can occur in subsets of patients with cystic fibrosis (CF) especially those with malabsorption and impaired growth. Although supplemental Zn has significantly reduced infections in various disorders, its efficacy has not been thoroughly investigated in CF. We performed a double blind placebo controlled pilot study to investigate the effect of daily 30 mg elemental Zn for 1 year on the rate of respiratory tract infections (RTIs), use of antibiotics and plasma cytokines in 26 children with CF (ages 7-18 years). Plasma Zn, Cu, inflammatory cytokines and ex vivo generation of IL-2 were measured at baseline and at the end of the study. The number of days of oral antibiotics was lower in Zn treated patients compared to placebo (P = 0.05). However, compared to placebo, the effect of Zn was greater in patients who exhibited low plasma Zn at baseline (P = 0.02) than those who had plasma Zn levels identical to normal subjects (P = 0.55). Zn supplementation was marginally effective in reducing percentage increase in plasma IL-6 and IL-8 while increasing the percentage change in ex vivo generation of IL-2 in isolated mononuclear cell. In conclusion, oral intake of 30 mg/day of Zn reduced the number of days of oral antibiotics used to treat RTIs in children with CF. A higher daily Zn dose may be needed to decrease RTIs and modify immune responses.

Recurrence analysis of strange nonchaotic dynamics in driven excitable systems

Numerous studies have shown that strange nonchaotic attractors (SNAs) can be observed generally in quasiperiodically forced systems. These systems could be one- or high-dimensional maps, continuous-time systems, or experimental models. Recently introduced measures of complexity based on recurrence plots can detect the transitions from quasiperiodic to chaotic motion via SNAs in the previously cited systems. We study here the case of continuous-time systems and experimental models. In particular, we show the performance of the recurrence measures in detecting transitions to SNAs in quasiperiodically forced excitable systems and experimental time series.

Analysis of skin-electrode impedance using concentric ring electrode

A significant contributor to artefact generation in surface electromyography (sEMG) and, functional electrical stimulation (FES) intensity is the skin-to-electrode impedance (Z(S/E)). While using electrolytic gels may initially lower Z(S/E), the impedance may not remain stable. It can vary over time due to changes in underlying structures such as sweat glands and physical deformations due to movements. An experiment seeking to identify major factors in the reduction of Z(S/E), and therefore mitigate these artefacts, was performed by varying a series of control factors on the concentric ring electrode (CRE). Unlike conventional disc electrodes, CREs have small surface areas which may exacerbate Z(S/E) changes. The factors tested were electrode material, electrode size, skin preparation, and surface pressure. This work analyzes how these factors in their various combinations effect changes in Z(S/E) and suggests protocols for improving recording or stimulation with CREs via lowered and consistent Z(S/E).

Detection of anti-Haemonchus contortus antibodies in sheep by dot-ELISA with immunoaffinity purified fraction of ES antigen during prepatency

Haemonchosis is a very common disease in small ruminants caused by H. contortus, a blood sucking parasite causing anaemia that may be fatal particularly to young animals. Therefore, detection of the infection during prepatent period is important for early treatment. Excretory-Secretory (ES) protein of H. contortus was purified through immunoaffinity chromatography. Dot -ELISA was performed with crude ES antigen as well as immunoaffinity purified fraction (F-1) with experimental and natural sera of sheep infected with H. contortus. Solid dot formation took place with 4 day, 1, 2 and 3 weeks post infection sera. Dot formation did not take place with negative control serum and uninfected control animal serum. When crude ES antigens was reacted to natural sheep sera having H. contortus infection, 60% sera samples showed solid dot formation whereas in F-1 fraction 75% of the sera samples showed solid dot indicating purified fraction was a more potent antigen. Crude ES and F-1 were also fractionated through SDS-PAGE. ES antigen revealed polypeptides in the range of 10 to 200 kDa of which 26, 32, 60 and 120 kDa were found more prominent. F-1 fraction on SDS-PAGE analysis revealed only four polypeptides of 26, 32, 60, and 120 of which 60 and 120 kDa were found to be most prominent. Results indicate that the purified fraction of ES antigen may be utilized for early diagnosis of haemonchosis. Further studies on cross antigenicity of this fraction with other nematode and trematode needs to be conducted.

In vivo demonstration of neuroinflammatory molecule expression in brain abscess with diffusion tensor imaging

BACKGROUND AND PURPOSE

Neuroinflammatory molecules, including tumor necrosis factor-alpha, interleukin1-beta, lymphocyte function associated molecule-1, and intercellular cell adhesion molecule-1 contribute to the development of brain abscess. We hypothesized that the high fractional anisotropy (FA) in the brain abscess cavity reflects the upregulation of these neuroinflammatory molecules.

MATERIALS AND METHODS

Diffusion tensor imaging (DTI) was performed in 24 patients with brain abscess and Staphylococcus aureus-treated as well as nontreated Jurket cell lines (at 4 time points: 1, 24, 48, and 72 hours). Neuroinflammatory molecules were quantified from the brain abscess cavity aspirate of the patients as well as from the heat-killed S aureus-treated and nontreated cell lines and correlated with DTI measures.

RESULTS

The DTI-derived FA strongly correlated with the presence of neuroinflammatory molecules in the pus as well as in S aureus-treated cell lines; no such correlation was observed in nontreated cell lines.

CONCLUSIONS

These data indicate that neuroinflammatory molecules confer high diffusion anisotropy inside the brain abscess cavity. We propose that increased FA reflects upregulated inflammatory response in brain abscess.

Characterization of adsorbed silane on fillers used in dental composite restoratives and its effect on composite properties

The purpose was to study the effect of silane treatment of fillers on viscosity, flexural strength, and hydrolytic degradation of experimental dental composite resins fabricated with these fillers. The fillers consisted of a mixture of barium glass and amorphous silica. The resin was mainly based on ethoxylated bisphenol A dimethacrylate and polycarbonate dimethacrylate. The adsorption of silane on the filler surface was characterized by FTIR. There was significant correlation between the adsorbed silane on filler surface and the silane concentration in silane/methanol solution used for filler treatment. The silane concentration varied from 0.75 to 14% by weight. An increase in silane concentration led to a decrease in viscosities of the corresponding composite resins. The flexural strengths of composites with silanated fillers were greater than that of composites with unsilanated fillers: however, no significant difference was found between the flexural strengths of various silanated groups. The resistance to hydrolytic degradation of different composites increased when the fillers were treated with silane and was the highest at 1.1% silane.

A kinematic description of the trajectories of Listeria monocytogenes propelled by actin comet tails

The bacterial pathogen Listeria monocytogenes propels itself in the cytoplasm of the infected cells by forming a filamentous comet tail assembled by the polymerization of the cytoskeletal protein actin. Although a great deal is known about the molecular processes that lead to actin-based movement, most macroscale aspects of motion, including the nature of the trajectories traced out by the motile bacteria, are not well understood. Here, we present 2D trajectories of Listeria moving between a glass-slide and coverslip in a Xenopus frog egg extract motility assay. We observe that the bacteria move in a number of fascinating geometrical trajectories, including winding S curves, translating figure eights, small- and large-amplitude sine curves, serpentine shapes, circles, and a variety of spirals. We then develop a dynamic model that provides a unified description of these seemingly unrelated trajectories. A key ingredient of the model is a torque (not included in any microscopic models of which we are aware) that arises from the rotation of the propulsive force about the body axis of the bacterium. We show that a large variety of trajectories with a rich mathematical structure are obtained by varying the rate at which the propulsive force moves about the long axis. The trajectories of bacteria executing both steady and saltatory motion are found to be in excellent agreement with the predictions of our dynamic model. When the constraints that lead to planar motion are removed, our model predicts motion along regular helical trajectories, observed in recent experiments.

Serum prostate-specific antigen levels in Middle Eastern men with subclinical prostatitis

OBJECTIVE

To investigate the influence of subclinical or histologically diagnosed prostatitis on serum prostate-specific antigen (PSA) in patients investigated for prostatic disease in Kuwait.

MATERIALS AND METHODS

Serum PSA was assayed in patients investigated for prostatic disease in Mubarak Al-Kabeer Hospital, Kuwait, between December 2002 and December 2004. These included patients undergoing transrectal ultrasound with needle biopsy of the prostate gland and those who were treated with transurethral resection of the prostate or retropubic prostatectomy. The tissue was evaluated for prostatitis as well as the underlying disease, and the type and severity of prostatitis were compared with levels of serum PSA.

RESULTS

Of the 331 tissue specimens, 18 (5.4%) did not show prostatitis, while 233 (70.4%) with benign prostate and 80 (24.2%) with malignant prostate disease showed prostatitis. Of 270 men with known serum PSA levels, 198 and 72 had benign and malignant prostate disease, respectively. Of the 198, 77 (41%) with benign prostate disease and prostatitis and of the 72, 52 (76%) with malignant prostate disease and prostatitis had serum PSA levels >10 ng/ml.

CONCLUSION

The data showed that although raised serum PSA is more commonly associated with prostate cancer, subclinical prostatitis is a significant source of high serum PSA in over 40% of men in Kuwait. That local factors may obscure the usefulness of serum PSA as a screening tool suggests the need for a locally applicable paradigm to identify prostate cancer.