bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring prostate thermal therapy with diffusion‐weighted MRI
Authors: Chen Jing , Daniel Bruce L. , Diederich Chris J. , Bouley Donna M. , van den Bosch Maurice A.A.J. , Kinsey Adam M. , Sommer Graham , Pauly Kim Butts
Published: May 2008

For MR‐guided minimally invasive therapies, it is important to have a repeatable and reliable tissue viability evaluation method. The use of diffusion‐weighted MRI (DWI) to evaluate tissue damage was assessed in 19 canine prostates with cryoablation or high‐intensity ultrasound (HIU) ablation. The apparent diffusion coefficient (ADC) trace value was measured in the treated tissue immediately upon the procedure and on the posttreatment follow‐up. For the acute lesions, the ADC value decreased to (1.05 ± 0.25) × 10–3 mm2/s, as compared to (1.64 ± 0.24) × 10–3 mm2/s before the treatment. There was no statistical difference between previously frozen or previously ultrasound‐heated lesions in terms of the 36% ADC reduction (P = 0.66). The ADC decrease occurred early during the course of the treatment, which appears to complicate DWI‐based thermometry. Over time, the ADC value increased as the tissue recovered and regenerated. This study shows that DWI could be a promising method to monitor prostate thermal therapies and to provide insight on tissue damage and tissue remodeling after injury. Magn Reson Med 59:1365–1372, 2008. © 2008 Wiley‐Liss, Inc.
Water spin dynamics during apoptotic cell death in glioma gene therapy probed by T1ρ and T2ρ
Authors: Sierra A. , Michaeli S. , Niskanen J.‐P. , Valonen P.K. , Gröhn H.I. , Ylä‐Herttuala S. , Garwood M. , Gröhn O.H.
Published: May 2008

Longitudinal and transverse relaxations in the rotating frame, with characteristic time constants T1ρ and T2ρ, respectively, have potential to provide unique MRI contrast in vivo. On‐resonance spin‐lock T1ρ with different spin‐lock field strengths and adiabatic T2ρ with different radiofrequency‐modulation functions were measured in BT4C gliomas treated with Herpes Simplex Virus thymidine kinase (HVS‐tk) gene therapy causing apoptotic cell death. These NMR tools were able to discriminate different treatment responses in tumor tissue from day 4 onward. An equilibrium two‐site exchange model was used to calculate intrinsic parameters describing changes in water dynamics. Observed changes included increased correlation time of water associated with macromolecules and a decreased fractional population of this pool. These results are consistent with destructive intracellular processes associated with cell death and the increase of extracellular space during the treatment. Furthermore, association between longer exchange correlation time and decreased pH during apoptosis is discussed. In this study, we demonstrated that T1ρ and T2ρ MR imaging are useful tools to quantify early changes in water dynamics reflecting treatment response during gene therapy. Magn Reson Med 59:1311–1319, 2008. © 2008 Wiley‐Liss, Inc.
Resolution of creatine and phosphocreatine 1H signals in isolated human skeletal muscle using HR‐MAS 1H NMR
Authors: Chen Jin‐Hong , Wu Yuhsin V. , DeCarolis Penelope , O'Connor Rachael , Somberg C. Joy , Singer Samuel
Published: May 2008

Proton NMR spectra of freshly isolated human skeletal muscle samples contain creatine and phosphocreatine resonances with distinct chemical shifts that are easily visualized with magic angle spinning (MAS, spinning the sample rapidly at 54.7° with respect to the magnetic field) methods. The identification of the phosphocreatine resonance was based on two findings: that (i) the possible small dipolar coupling does not contribute to line splitting under rapid MAS, and (ii) the 1H signal decreases concurrently with the phosphocreatine resonance observed in 31P NMR experiments. In the MAS 1H spectra, the phosphocreatine resonance remains a singlet with a linewidth of less than 3 Hz. The creatine resonances are split into two peaks with linewidths at half height of approximately 2 and 6 Hz, respectively. The resonance with the broader linewidth represents creatine that is significantly motion‐restricted and suggests that a creatine pool in muscle tissue is highly compartmentalized. Magn Reson Med 59:1221–1224, 2008. © 2008 Wiley‐Liss, Inc.
1H MR spectroscopic imaging of phospholipase‐mediated membrane lipid release in apoptotic rat glioma in vivo
Authors: Liimatainen Timo J. , Erkkilä Arja T. , Valonen Piia , Vidgren Helvi , Lakso Merja , Wong Garry , Gröhn Olli H.J. , Ylä‐Herttuala Seppo , Hakumäki Juhana M.
Published: May 2008

The purpose of the current study was to determine regional spatiotemporal differences and to gain insight on the mechanisms responsible for lipid accumulation during apoptotic cell death using in vivo MR spectroscopic imaging in combination with histology and biochemical membrane lipid analyses. Rats bearing BT4C gliomas were treated with ganciclovir (GCV) for 14 days, and combined in vivo quantitative MR spectroscopic imaging (MRSI) of gliomas with histology and a biochemical analysis of major cell membrane constituents. By using 1H MRSI in vivo in combination with histology, we were able to demonstrate previously unattainable regional lipid concentration differences in tumors during GCV‐induced apoptosis, with 5‐μL tissue volume resolution. Our results also show that, during treatment, phospholipase A2 (PLA2) expression is significantly elevated by 37 ± 13% (P < 0.05) and tumor cell membranes loose a significant proportion of unsaturated fatty acyl moieties (56 ± 6 mmol/kg, P < 0.05). These changes are reflected in both histology and significant MR‐visible lipid accumulation, demonstrating that phospholipid hydrolysis in tissue undergoing apoptosis can be imaged with MRSI. Our work demonstrates the versatility of 1H MRSI in studying apoptosis in vivo, which is likely to pave way for the use of MRSI in both experimental and clinical anticancer trials. Magn Reson Med 59:1232–1238, 2008. © 2008 Wiley‐Liss, Inc.
Respiratory self‐gated four‐dimensional coronary MR angiography: A feasibility study
Authors: Lai Peng , Larson Andrew C. , Park Jaeseok , Carr James C. , Li Debiao
Published: May 2008

The four‐dimensional (4D) coronary MR angiography (MRA) approach has been developed to eliminate the need for accurate determination of the acquisition window and trigger delay time. Diaphragm navigator (NAV) has been the conventional respiratory gating method for free‐breathing coronary MRA. However, NAV echo acquisition interrupts the continuous radiofrequency pulse application required for 4D steady‐state free precession coronary MRA. The objective of this work was to investigate the feasibility of a respiratory self‐gating (RSG) technique for 4D coronary MRA and its effectiveness by comparing with retrospective NAV gating. Data were acquired continuously throughout the cardiac cycle and retrospectively remapped to cardiac phases based on the electrocardiogram signal simultaneously recorded. An RSG signal extracted from a direct measurement of the heart position was used for retrospective respiratory gating and motion correction. In seven healthy volunteers, 4D MRA images were reconstructed, allowing retrospective assessment of the cardiac motion of the coronary artery and selection of the images with the best vessel delineation. Statistical analysis shows that 4D RSG provides coronary artery delineation comparable to mid‐diastole images acquired using NAV. Respiratory self‐gating is an effective method for eliminating respiratory motion artifacts and allows 4D coronary MRA during free breathing. Magn Reson Med 59:1378–1385, 2008. © 2008 Wiley‐Liss, Inc.
B1‐insensitive fast spin echo using adiabatic square wave enabling of the echo train (SWEET) excitation
Authors: Madhuranthakam Ananth J. , Busse Reed F. , Brittain Jean H. , Rofsky Neil M. , Alsop David C.
Published: May 2008

Abdominal images at 3T acquired with fast spin echo (FSE) sequences often exhibit signal voids due to RF transmit field inhomogeneities. Theory suggests, however, that the repeated refocusing pulses of FSE are capable of maintaining signal even at reduced RF amplitudes if the magnetization is suitably prepared. Here we propose a modified excitation strategy for FSE that is more robust to transmit field inhomogeneities than conventional FSE. The new excitation approach replaces the standard 90° excitation pulse with a discretely sampled hyperbolic secant pulse that creates a square wave longitudinal magnetization as a function of gradient and off‐resonance induced phase shifts between the subsequent echoes of the FSE sequence. This pulse is followed by the conventional train of refocusing pulses except that the first few pulses increase from near zero to the desired refocusing amplitude. Simulations and in vivo results at 3T indicate preserved image quality and much greater robustness of this new sequence to nonuniform RF fields. This robustness comes at the cost of 20% reduction in signal when the RF field is uniform and increased motion sensitivity. This RF field‐insensitive sequence may overcome challenges of body imaging at high field and in patients with ascites. Magn Reson Med 59:1386–1393, 2008. © 2008 Wiley‐Liss, Inc.
Glial fibrillary acidic protein: A marker of axonal Guillain–Barrè syndrome and outcome
Authors: Notturno Francesca , Caporale Christina M. , De Lauretis Angelo , Uncini Antonino
Published: May 2008

Glial fibrillary acid protein (GFAP) is increased in serum and cerebrospinal fluid of patients with dementia, traumatic brain injury, stroke, and multiple sclerosis. To determine whether GFAP is increased in Guillain–Barré syndrome (GBS) we evaluated serum GFAP in 30 controls, 20 patients with acute inflammatory demyelinating neuropathy (AIDP), and 17 with primary axonal GBS. Serum GFAP levels were increased in axonal GBS (median, 0.74) compared with controls (median, 0.41; P < 0.0001) and AIDP (median, 0.58; P = 0.0015). GFAP levels correlated with Hughes grades (serum r = 0.74; P < 0.0001) 6 months after neuropathy onset. Applying the cutoff value in serum of 0.63 to the diagnosis of axonal GBS, we obtained a sensitivity of 76.5% and a specificity of 86%. Thus, serum GFAP levels may be used in GBS as a diagnostic marker of the axonal variant and to predict outcome. Muscle Nerve, 2008
Obturator mononeuropathy caused by lipomatosis of the nerve: A case report
Authors: Nardone Raffaele , Venturi Alessandro , Ladurner Gunther , Golaszewski Stefan , Psenner Konrad , Tezzon Frediano
Published: May 2008

We report a patient who presented with the clinical features of obturator mononeuropathy. Abdomino‐pelvic computed tomography revealed a fusiform mass in the right perivesical space; magnetic resonance imaging (MRI) showed characteristic “coaxial‐cable‐like” appearance in cross‐section and “spaghetti‐like” appearance in longitudinal section, pathognomonic of lipomatosis of the nerve. Nerve lipomatosis as the cause of obturator neuropathy has not been previously reported. MRI provides definite and graphic proof of the diagnosis. Muscle Nerve, 2008
Effect of small motor unit potentials on the motor unit number estimate
Authors: van Dijk Johannes P. , Zwarts Machiel J. , Schelhaas Helenius J. , Stegeman Dick F.
Published: May 2008

Small surface motor unit potentials (S‐MUPs) may have a negative influence on the variability of the motor unit number estimate (MUNE). According to published consensus criteria S‐MUPs with a negative peak amplitude smaller than 10 μV should be omitted. The effect of omitting small S‐MUPs on the MUNE was evaluated using a simulation model. The model incorporated a healthy and amyotrophic lateral sclerosis (ALS) distribution formed with real S‐MUPs. Using a random drawing process the MUNE was calculated with and without small S‐MUPs. In the healthy population 27% of all S‐MUPs were small. MUNE determined without these S‐MUPs was marginally less variable. However, MUNE values dropped about 24% at a sample size of 20. In ALS, only 12% of the total population of 130 S‐MUPs were small. MUNE dropped about 12% without the small S‐MUPs. By omitting small S‐MUPs the differences between the healthy and ALS distributions become smaller. Therefore, incorporating small S‐MUPs in the estimate is suggested. © 2008 Wiley Periodicals, Inc. Muscle Nerve, 2008
Nine‐year case history of monofocal motor neuropathy
Authors: Manganelli Fiore , Pisciotta Chiara , Iodice Rosa , Calandro Sara , Santoro Lucio
Published: May 2008

A 36‐year‐old man had a 6‐year history of progressive left hand and finger extension weakness. Extensive electrophysiological studies showed only a partial motor conduction block along the left radial nerve at the mid‐arm. Several intravenous immunoglobulin treatments were clinically successful. A 3‐year follow‐up did not show any clinical or electrophysiological involvement of other nerves. A monofocal motor neuropathy, as a variant of multifocal motor neuropathy, was diagnosed. Muscle Nerve, 2008
PAX3/7 expression coincides with myod during chronic skeletal muscle overload
Authors: Hyatt Jon‐Philippe K. , McCall Gary E. , Kander Elizabeth M. , Zhong Hui , Roy Roland R. , Huey Kimberly A.
Published: May 2008

Paired box (Pax) proteins 3 and 7 are key determinants for embryonic skeletal muscle development by initiating myogenic regulatory factor (MRF) gene expression. We show that Pax3 and 7 participate in adult skeletal muscle plasticity during the initial responses to chronic overload (≤7 days) and appear to coordinate MyoD expression, a member of the MRF family of genes. Pax3 and 7 mRNA were higher than control within 12 h after initiation of overload, preceded the increase in MyoD mRNA on day 1, and peaked on day 2. On days 3 and 7, Pax7 mRNA remained higher than control, suggesting that satellite cell self‐renewal was occurring. Pax3 and 7 and MyoD protein levels were higher than control on days 2 and 3. These data indicate that Pax3 and 7 coordinate the recapitulation of developmental‐like regulatory mechanisms in response to growth‐inducing stimuli in adult skeletal muscle, presumably through activation of satellite cells. Muscle Nerve, 2008
Hormonal and nutritional control of L‐carnitine uptake in myoblastic C2C12 cells
Authors: Borgne Françoise Le , Rigault Caroline , Georges Béatrice , Demarquoy Jean
Published: May 2008

L‐Carnitine plays an important role in skeletal muscle bioenergetics, and its bioavailability and thus its import may be crucial for muscle function. We studied the effect of thyroid hormone, insulin, and iron overload, hormones and nutrients known to alter muscle metabolism, on L‐carnitine import into C2C12 cells. We report here L‐carnitine uptake is increased by thyroid hormones and decreased by iron. Insulin was found to be ineffective in altering the L‐carnitine uptake. Muscle Nerve, 2008
Chronic inflammatory demyelinating polyneuropathy–like disorder associated with amyotrophic lateral sclerosis
Authors: Rajabally Yusuf A. , Jacob Saiju
Published: May 2008

The association between demyelinating neuropathy and amyotrophic lateral sclerosis (ALS) has been reported rarely. We report four patients who presented with clinical features and investigations suggestive of a neuropathy but who later progressed and received a final diagnosis of ALS according to the original El Escorial criteria. Three patients met the European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) 2006 definition for “definite” chronic inflammatory demyelinating polyneuropathy (CIDP), as well as the American Academy of Neurology (AAN) 1991 and Nicolas et al. [2002] electrodiagnostic criteria for CIDP. Two of them showed segmental demyelination on teased‐fiber preparations and one had a raised cerebrospinal fluid protein level. Another patient met the Nicolas et al. CIDP criteria and presented with brachial plexus hyperintensity on T2‐weighted magnetic resonance imaging, indicative of an inflammatory process. No significant objective response to immunomodulatory treatment was observed in any of these patients who all subsequently progressed unfavorably. Muscle Nerve, 2008
Adolescent spinal muscular atrophy with calf hypertrophy and a deletion in the SMN gene
Authors: Yiu Eppie M. , Ravat Sangeeta , Ryan Monique M. , Shield Lloyd K. , Smith Lindsay J. , Kornberg Andrew J.
Published: May 2008

Spinal muscular atrophy (SMA) is generally associated with proximal weakness and muscle wasting. An X‐linked variant with calf hypertrophy has been reported. We describe a young man with SMA type 4 with prominent calf hypertrophy in whom DNA analysis showed a homozygous deletion of exons 7 and 8 in the telomeric copy of the survival motor neuron gene. Calf hypertrophy may be seen uncommonly in autosomally inherited SMA. Muscle Nerve, 2008
Frequency of cyclic lumbar loading is a risk factor for cumulative trauma disorder
Authors: Lu Dawei , Le Peter , Davidson Bradley , Zhou Bing He , Lu Yun , Patel Vikas , Solomonow Moshe
Published: May 2008

Epidemiologic studies indicate that repetitive (cyclic) occupational activities lead to a cumulative trauma disorder (CTD), and the frequency or velocity of the movement is one of the risk factors. Experimental neurophysiological evidence to confirm the epidemiology is not available. The response of the multifidus muscles to cyclic loading in anterior lumbar flexion–extension was assessed to test the hypothesis that high‐frequency loading may induce an acute neuromuscular disorder leading to CTD. Two groups of feline preparations were subjected to cyclic loading with a peak of 20 N: one at 0.25 HZ and the second at 0.5 HZ, with an equal number of cycles. Electromyogram (EMG), lumbar displacement and load were recorded throughout the loading periods and during single‐cycle tests over a 7‐hour rest period following the load–rest sessions. A model was developed to quantify the creep and neuromuscular responses, and analysis of variance (ANOVA) was applied to assess significance of the results. The group exposed to 0.5 HZ exhibited spontaneous spasms followed by sustained spasms during the loading periods. During the 7‐hour recovery period, a significant (P < 0.001) delayed hyperexcitability as well as sustained spasms of the multifidi were present in the last 5 hours, confirming a significant (P < 0.024 to P < 0.042) acute neuromuscular disorder. High‐frequency cyclic loading of the lumbar spine may trigger a severe acute neuromuscular disorder, as evidenced by the sustained spasms and delayed hyperexcitability, and should be considered as a risk factor. We suggest that workers avoid high‐frequency exposure to cyclic activity in order to prevent the development of cumulative trauma disorder. Muscle Nerve, 2008
Neurogenic detrusor overactivity: Comparison between complete and incomplete spinal cord injury patients
Authors: Moslavac S. , Dzidic I. , Kejla Z.
Published: May 2008

Aims

To compare leak‐point intravesical pressure and cystometric capacity in complete and incomplete spinal cord injury (SCI) patients with neurogenic detrusor overactivity (NDO).

Methods

Retrospective study of filling cystometry at non‐physiological filling rate in 80 SCI patients at rehabilitation or annual check‐up using Dantec Etude urodynamic machine.

Results

Fifty neurologically complete (ASIA (American Spinal Injury Association) A) and 30 incomplete (ASIA B–E) were diagnosed with neurogenic detrusor overactivity, all with suprasacral level of injury. Mean Pves leak‐point pressure (Pves LPP) at cystometric capacity for ASIA A group was 79 ± 30 cmH2O (range 26–140) and mean Pves LPP for ASIA B–E group was 70 ± 29 cmH2O (range 25–130). There was no significant difference between groups (P = 0.234). Mean CC (cystometric capacity) for ASIA A group was 239 ± 107 ml (range 47–526) and mean CC for ASIA B–E group was 227 ± 125 ml (range 42–500). Again, no significant difference was found (P = 0.655).

Conclusions

No difference in cystometric capacity and intravesical leak point pressure at terminal detrusor overactivity was shown between complete and incomplete spinal cord injury patients in our survey, that is, represented findings are equally unfavorable for both groups. Incomplete SCI patients with NDO should be tested with cystometry and observed with same caution as we proceed in complete SCI patients. Neurourol. Urodynam. 27:504–506, 2008. © 2008 Wiley‐Liss, Inc.
Modeling the clinical assessment of men with suspected obstructed voiding using Bayes' Theorem
Authors: Caffarel Jennifer , Griffiths Clive , Pickard Robert , Robson Wendy , Drinnan Michael
Published: May 2008

Aims

Pressure‐flow studies (PFS) are the only reliable way to diagnose bladder outlet obstruction (BOO) in men with lower urinary tract symptoms (LUTS). However, in routine clinical practice, BOO is usually inferred by any of a number of tests (symptoms, flow rate, prostate size…). Bayes' Theorem provides a mathematical method, which may be similar to the process used by clinicians, for combining the results of multiple tests to reach a diagnosis. We have applied Bayes' Theorem to the results of several tests known weakly to predict BOO in men with LUTS to assess if they improve the diagnostic accuracy of a flow rate test which alone is known to predict obstruction moderately well.

Methods

We applied Bayes' Theorem to data from 50 patients using Qmax alone and with the inclusion of additional variables (IPSS, PSA, and residual urine), to establish individual probabilities of BOO. The chi‐squared statistic (with trend) was used to compare the relative diagnostic values, against the BOO index calculated from the results of subsequent PFS.

Results

The diagnostic value of Qmax alone (chi‐squared = 9.2, P = 0.002), was superior than that for the Bayesian model using the combination of tests available (chi‐squared = 4.9, P = 0.026).

Conclusions

Although in our sample relevant additional tests do not improve the diagnostic power of Qmax as a predictor of BOO, we believe the Bayesian approach is conceptually suited to modeling clinical decision making but may be better tested for a more clinically relevant outcome such as treatment response. Neurourol. Urodynam. 27:797–801, 2008, © 2008 Wiley‐Liss, Inc.
Numerical studies of a nonlinear heat equation with square root reaction term
Authors: Buckmire Ron , McMurtry Karl , Mickens Ronald E.
Published: May 2008

Interest in calculating numerical solutions of a highly nonlinear parabolic partial differential equation with fractional power diffusion and dissipative terms motivated our investigation of a heat equation having a square root nonlinear reaction term. The original equation occurs in the study of plasma behavior in fusion physics. We begin by examining the numerical behavior of the ordinary differential equation obtained by dropping the diffusion term. The results from this simpler case are then used to construct nonstandard finite difference schemes for the partial differential equation. A variety of numerical results are obtained and analyzed, along with a comparison to the numerics of both standard and several nonstandard schemes. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009
Thermal and mechanical properties of electron beam irradiated poly(vinyl chloride)/polystyrene blends
Authors: Senna Magdy M.H. , Hussein Yousry A. , Abdel‐Moneam Yasser K.
Published: May 2008

The effect of electron beam irradiation on the thermal and mechanical properties of poly(vinyl chloride)/polystyrene (PVC/PS) blends and PVC/PS blends containing epoxidized natural rubber (ENR) was studied. The thermogravimetric analysis study showed that the thermal decomposition of the plasticized PVC individual polymer goes through two stages, whereas PS decomposes through one stage. However, the temperature of the maximum rate of reaction (Tmax) of PS is much higher than that for PVC and their blends. Meanwhile, the Tmax was found to increase with increasing PS ratios in the blend. The thermal stability of PVC/PS blends was greatly increased after electron beam irradiation in comparison with unirradiated blends. Moreover, the addition of ENR to PVC/PS increased the thermal stability. On the other hand, the mechanical properties in terms of tensile strength and elongation at break of PVC/PS blends are lower than pure PVC polymer because of the immiscibility. However, the addition of ENR to the PVC/PS (80/20) blend increased the elongation at break from 114 to 321% associated with a small effect on the tensile properties. These behaviors were supported by structure morphology studies observations, which indicate an improvement in the interfacial adhesion between the phases. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
The effect of gestational age on the outcome of second‐trimester termination of pregnancies for foetal abnormalities
Authors: Lo T. K. , Lau W. L. , Lai F. K. , Lam H. , Tse H. Y. , Leung W. C. , Chin R. K. H.
Published: May 2008

Objective

To explore the effect of gestational age on the outcome of second‐trimester termination of pregnancies for foetal abnormalities.

Method

A retrospective study was conducted on 280 pregnancies terminated for foetal abnormalities in the second trimester using vaginal misoprostol. The gestational age at termination was divided into three groups: 13–16 weeks, 17–20 weeks and 21–23 weeks. The likelihood of (1) abortion within 24 h of commencement of misoprostol, (2) incomplete abortion and (3) experiencing significant side effects was compared among these three gestational groups after adjusting for maternal age, parity and body mass index (BMI).

Results

Compared to termination after 20 weeks, pregnancy termination for foetal abnormality before 17 weeks of gestation was associated with higher chance of incomplete abortion (OR 2.2, 95% CI 1.07–4.61, p = 0.032) and lower chance of experiencing significant side effects (OR 0.11, 95% CI 0.01–0.91, p = 0.041).

Conclusion

Women undergoing pregnancy termination for foetal abnormalities in the early second trimester should be informed of possible higher chance of incomplete abortion. Copyright © 2008 John Wiley & Sons, Ltd.
Regression of fetal cerebral abnormalities by primary cytomegalovirus infection following hyperimmunoglobulin therapy
Authors: Nigro Giovanni , Torre Renato La , Pentimalli Henny , Taverna Paola , Lituania Mario , de Tejada Begoňa Martinez , Adler Stuart P.
Published: May 2008

Objective

To assess the effects of maternal and intra‐amniotic hyperimmunoglobulin (HIG) infusions among cytomegalovirus (CMV) infected fetuses with ultrasound abnormalities following a primary CMV infection.

Patients and Methods

The subjects were fetuses with CMV‐associated cerebral and other ultrasound abnormalities. Three mothers were treated with HIG infusions during pregnancy and two were untreated. Fetal ventricle size, organ echodensity and placental thickness were measured by ultrasound before and after HIG infusions. The children were evaluated between 3 and 7 years of age.

Results

The ventriculomegaly of all three fetuses of HIG‐treated mothers regressed and the ascites, hepatic echodensities, periventricular echodensities, and intestinal echodensities disappeared. Their sensorial, mental and motor development was normal at 4, 4.7, and 7 years of age. In contrast, both infants born of untreated mothers had signs and symptoms of severe CMV cerebropathy.

Conclusion

The outcomes of the infants born to HIG‐treated mothers support the efficacy of HIG as a treatment for CMV‐infected fetuses with ultrasound cerebral abnormalities. Copyright © 2008 John Wiley & Sons, Ltd.
The best approach for early prediction of fetal gender by using free fetal DNA from maternal plasma
Authors: Picchiassi Elena , Coata Giuliana , Fanetti Alessia , Centra Michela , Pennacchi Luana , Di Renzo Gian Carlo
Published: May 2008

Objectives

Detection of free fetal DNA (ffDNA) in maternal blood during pregnancy has given rise to the possibility of developing new noninvasive approaches for early prenatal diagnosis.

On a large‐scale study, two protocols of real‐time polymerase chain reaction (PCR) were compared in order to establish which Y‐specific locus, either multicopy DYS14 or single copy SRY sequence, was the most suitable for developing a test with high diagnostic efficiency for early fetal gender assessment. The second aim was to assess whether the combination of the two detection systems could increase the performance of the prenatal test.

Methods

We analyzed 145 plasma samples from healthy pregnant women between 11 and 12 weeks of singleton gestation. For each sample, fetal gender was determined by using both protocols (DYS14 and SRY) during the same real‐time PCR run.

Results

The data obtained by the DYS14 and SRY assays showed an efficiency in fetal gender prediction of 97.9 and 80%, respectively. It is not advisable to combine the two protocols because this association does not help in further improvements in fetal gender prediction.

Conclusions

DYS14 assay is the best approach for early fetal gender assessment because it is more sensitive, accurate, and efficient than the SRY assay. Copyright © 2008 John Wiley & Sons, Ltd.
Interstitial laser therapy for fetal reduction in monochorionic multiple pregnancy: loss rate and association with aplasia cutis congenita
Authors: O'Donoghue Keelin , Barigye Olivia , Pasquini Lucia , Chappell Lucy , Wimalasundera Ruwan C. , Fisk Nicholas M.
Published: May 2008

Objective

To evaluate experience with interstitial laser therapy for intrafetal vascular ablation in monochorionic (MC) multiple pregnancy.

Methods

MC pregnancies that underwent fetal reduction between 1998 and 2007 by interstitial laser therapy were reviewed. Indications were twin reversed arterial perfusion sequence (TRAP) (n = 10), twin‐to‐twin transfusion (6), discordant abnormality (7) or growth (1) and high‐order multiples (6).

Results

Thirty pregnancies treated at 15 weeks (median, range: 11 weeks–20 weeks, 5 days) had no technical failures but four manifested procedure‐related amniorrhexis. Four of 38 remaining fetuses suffered intrauterine death (IUFD) within 24 h, giving an early procedure‐related fetal loss rate of 10% per pregnancy and 11% per fetus. A further five IUFDs occurred within 2 weeks, giving a maximum procedure‐related loss rate of 27% per pregnancy and 24% per fetus. Median gestation at delivery was 37 weeks (18 weeks, 1 day–41 weeks, 3 days) for pregnancies continuing > 2 weeks. Perinatal survival was 26 of 38 (68%) in nonreduced fetuses. Two of 26 neonates (8%) were diagnosed with aplasia cutis congenita (ACC).

Conclusion

Interstitial laser therapy in complicated MC pregnancies carries significant risks of unintended fetal loss and may be associated with ACC. Copyright © 2008 John Wiley & Sons, Ltd.
Diffusion of interferon beta in Iran and its utilization in Tehran
Authors: Palesh Mohammad , Jonsson Pia Maria , Jamshidi Hamidreza , Wettermark Björn , Tomson Göran , Fredrikson Sten
Published: May 2008

Purpose

There are few studies on the diffusion of expensive new therapies in low‐ or middle‐income countries. The objectives of this study were to describe the diffusion of interferon beta for the treatment of patients with multiple sclerosis (MS) in Iran and to analyze its use in a cohort of 890 patients in Tehran registered in the Iranian MS Society (IMSS) registry.

Methods

Data on the diffusion of interferon beta drugs from 2000 to 2004 in Iran were obtained from the Ministry of Health (MOH). Data on the utilization of interferon beta in selected patient groups were collected from routine clinical data of the IMSS in a sample of population in Tehran province from 2003 to 2005.

Results

Interferon beta had a rapid diffusion in Iran during the study period, and it was used in all 28 provinces in 2004, however, much less in the poor provinces. Interestingly, interferon beta was prescribed to 68% of the patients in Tehran registered in the IMSS registry during 2003–2005. The usage of interferon beta as registered in the IMSS was higher (p < 0.0001) among insured than uninsured patients.

Conclusion

The use of interferon beta treatment has grown considerably in Iran. In Tehran, interferon beta seems to be mainly used by young ambulatory patients with relapsing–remitting MS, indicating a rational drug use. Copyright © 2008 John Wiley & Sons, Ltd.
Material characterization of components and assembled behavior of a composite liner for rehabilitation of cast iron pressure pipes
Authors: Brown Michael , Fam Amir , Moore Ian D.
Published: May 2008

Work is underway to determine the stability limit states for a cast in place composite liner system used to repair cast iron pressure water pipes. To establish its performance in bridging ring fractures, perforations, and other failures in the cast iron “host” pipe, it is important that the material characteristics of this composite liner be determined. This study characterizes the mechanical properties of this liner in both the longitudinal and circumferential directions, and develops a method to achieve this goal. A technique is developed to form the liner from its individual components and prepare coupons with end tabs. Test results for coupons oriented parallel to the axis of the pipe (i.e., in the longitudinal direction) agree well with those obtained from coupons cut from a liner exhumed from an actual field installation. Since the coupons formed in the laboratory are flat, the same technique is used to test the liner in the hoop (or circumferential) direction. Tensile strength and stiffness in the hoop direction are 45% higher than that in the longitudinal direction. Tests performed on the individual components of the liner are also reported, and these explain the bilinear stress–strain response. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Nonisothermal crystallization of high density polyethylene and nanoscale calcium carbonate composites
Authors: Huang Jiann‐Wen , Wen Ya‐Lan , Kang Chiun‐Chia , Tseng Wei‐Jen , Yeh Mou‐Yung
Published: May 2008

Nonisothermal crystallization of high density polyethylene (HDPE)/maleic anhydride‐modified HDPE(manPE)/nanoscale calcium carbonate (CaCO3) nanocomposite was investigated by means of wide angle X‐ray diffraction (WAXD), polarized optical microscopy (POM), and differential scanning calorimetry (DSC). WAXD indicated that the crystallinity was reduced with the addition of CaCO3. The spherulite size of HDPE increased in the presence of manPE, but decreased when CaCO3 was added from observation of POM. A modified Avrami analysis, Ozawa analysis, and Liu analysis were applied to the nonisothermal crystallization process. Crystallizability followed the order: HDPE/manPE/CaCO3 > HDPE/CaCO3 > HDPE/manPE > HDPE when undercooling was taken into account. Dependence of the effective activation energy on the relative crystallinity was estimated by the Friedman equation, and the results were used to calculate the parameters (Kg and U*) of Lauritzen‐Hoffman's equation by Vyazovkin's method. These results indicate that the addition of maleic anhydride groups and CaCO3 tend to promote the nucleation of spherulites on their surfaces and lead to epitaxial growth of the crystallites. But at the same time, manPE and CaCO3 particles may hinder the transport of the molecule chains resulting in a decrease of the crystallization growth rate. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
A new method for producing high melt strength polypropylene with reactive extrusion
Authors: Tang Hongxia , Dai Wenli , Chen Baiquan
Published: May 2008

A high‐melt‐strength polypropylene (HMSPP) was prepared using a twin‐screw reactive extruder from a commercial isotactic polypropylene through two stages, first, maleic anhydride is grafted to polypropylene to obtain a maleic anhydride‐grafted polypropylene (PP‐g‐MA), and then the grafted polymer is reacted with epoxy to extend the branched chain. Fourier transformed infrared spectroscopy indicated that maleic anhydride was grafted on polypropylene and reacted with epoxy. Melt flow rate and sag resistance test showed that the melt strength of the HMSPP improved considerably. Differential scanning calorimetry test showed that the long chain branches (LCBs) act as a nucleating agent in the crystallization of the HMSPP, which leads to a high crystallization temperature and crystallinity. Furthermore, the LCB efficiency of the HMSPP can also be calculated by analyzing its rheological property. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Temperature dependence of electrical resistivity in carbon nanofiber/unsaturated polyester nanocomposites
Authors: Natsuki Toshiaki , Ni Qing‐Qing , Wu Shi‐Hong
Published: May 2008

This article described the temperature dependence of electrical resistivity for carbon nanofiber (CNF)/unsaturated polyester resin (UPR) nanocomposites prepared by a solvent evaporation method. It was found that the CNF/UPR nanocomposites had quite low electrical percolation threshold due to CNFs having a large aspect ratio and being well dispersed into the UPR matrix. A sharp decrease in the electrical resistivity was observed at about 1 wt% CNF content. The influence of CNF content on the electrical resistivity was investigated as a function of temperature in detail. The nanocomposites showed a positive temperature coefficient effect for the resistivity, and had a strong temperature dependence near the percolation threshold. When the number of thermal cycles was increased, the electrical resistivity decreased and had a weak temperature dependence, especially in the case of melting temperature. Moreover, the size influences of CNFs on the electrical properties of nanocomposites were analyzed and discussed. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
A novel fabrication route for auxetic polyethylene, part 2: Mechanical properties
Authors: Webber R.S. , Alderson K.L. , Evans K.E.
Published: May 2008

Auxetic ultra high molecular weight polyethylene (UHMWPE) has been fabricated by omitting the extrusion stage usually required to form the characteristic nodule‐fibril microstructure of this material. This new route consists of compaction followed by multiple sintering treatments, with the best results using two successive sintering treatments. This article examines the mechanical properties of cylindrical compacts subjected to between one and four successive sintering treatments. The indentation resistance of the double‐sintered material was found to be 2.5 times that of conventionally processed UHMWPE and similar to that found in the extruded form of auxetic polyethylene. The flexural strength and strain to failure increase dramatically with the first sintering treatment and then remain almost constant. This processing route has potential for the production of more complex, useful shapes than can currently be produced since it removes the limitations imposed by the geometry of the barrel required for the extrusion stage. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Influence of polydispersity of crystallizable segments on the properties of segmented block copolymers
Authors: Biemond G.J.E. , Feijen J. , Gaymans R.J.
Published: May 2008

Poly(ether‐ester‐amide)s (PEEAs) based on poly(tetramethylene oxide) and tetra‐amide segments were synthesized by a solution/melt polymerization. The tetra‐amide segments (T6A6T) were based on adipic acid (A), terephthalic acid (T), and hexamethylene diamine (6), and were synthesized prior to the polymerization. Monodisperse tetra‐amide segments, i.e. T6A6T, as well as polydisperse segments, consisting of a mixture of uniform segments of diamide (T6T), tetra‐amide (T6A6T), and hexa‐amide (T6A6A6T), were utilized in the preparation of the PEEAs. In this way, a polydispersity index ranging from 1.0 to 1.09 could be obtained. In addition, a random copolymer, synthesized by a one‐pot polymerization, was also studied and the copolymer had a polydispersity of 1.2. The low polydispersity of the one‐pot synthesis amide segments was mainly due to the uneven reactivity of the terephthalic ester groups. The properties of copolymers were studied by DSC, FTIR, DMTA, compression set, and tensile set measurements. When the polydispersity of the amide segments was increased, the copolymers displayed a slower crystallization, a lower final crystallinity, a broader melting transition, a decreased storage modulus at room temperature, as well as a decreased yield strength and inferior elastic properties. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Effect of intercalating agents on clay dispersion and thermal properties in polyethylene/montmorillonite nanocomposites
Authors: Stoeffler Karen , Lafleur Pierre G. , Denault Johanne
Published: May 2008

Alkyl pyridinium, 1‐vinyl alkyl imidazolium, 1,3‐dialkyl imidazolium, and tetraalkyl phosphonium bromides were successfully used as intercalants for the preparation of highly thermally stable organophilic montmorillonites. Nanocomposites of linear low density polyethylene (LLDPE) and linear low density polyethylene grafted with maleic anhydride (LLDPE/LLDPE‐g‐MAH) were prepared from those organoclays. The micro‐ and nano‐dispersions were analyzed through X‐ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM): intercalation and/or partial exfoliation were found to occur only for formulations based on organoclays having an initial basal distance higher than 20 Å, suggesting the existence of a critical interfoliar distance for the delamination of silicate layers in a noninteracting polymer matrix. The properties of the nanocomposites were analyzed through differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and oscillatory rheometry. The dynamic crystallization of LLDPE was not significantly affected by the presence of clay. TGA in oxidative atmosphere proved to be very sensitive to the dispersion state of the organoclay: the thermal stability was drastically enhanced for intercalated and partially exfoliated formulations. However, the inherent thermal stability of the organoclay did not appear to influence significantly the overall thermal stability of the composite in the range of temperatures investigated (160–230°C). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers.
Synthesis of novel bis(β‐cyclodextrin)s linked with aromatic diamine and their molecular recognition with model substrates
Authors: Zhao Yan , Liu Xiao‐Qing , Gu Juan , Wang Li‐Qin , Zhu Hong‐You , Huang Rong , Wang Yu‐Fei , Yang Zi‐Ming
Published: May 2008

Novel β‐cyclodextrin (β‐CD) dimers with aromatic diamine linkers, 1,3‐(aminomethyl)‐benzylamine‐bridged bis(6‐amino‐6‐deoxy‐β‐CD) (2), 4,4′‐diaminodiphenylmethano‐bridged bis(6‐amino‐6‐deoxy‐β‐CD) (3), and 4,4′‐ ethylenedianiline‐bridged bis(6‐amino‐6‐deoxy‐β‐CD) (4), were synthesized. The inclusion complexation behaviors of these compounds, together with 4,4′‐aminophenyl ethyl‐bridged bis(6‐amino‐6‐deoxy‐β‐CD) (5), with substrates such as acridine red (AR), neutral red (NR), ammonium 8‐anilino‐1‐naphthalenesulfonate (ANS), sodium 2‐(p‐toluidinyl) naphthalenesulfonate (TNS), rhodamine B (RhB), and brilliant green (BG), were investigated by ultraviolet, fluorescence, circular dichroism, and 2D NMR spectroscopy. The results indicated that the two linked CD units cooperatively bound to a guest, and the molecular binding affinity toward substrates, especially curved guest ANS and linear guests such as NR and AR, was increased. The linker length between two CD units played a crucial role in the molecular recognition of the hosts with guest dyes. The binding constants of the hosts for AR, TNS, ANS, and RhB decreased with increasing linker length in hosts 2‐4. Moreover, structurally similar hosts 3 and 5 exhibited very different binding behavior for the guests. Host 5 showed much higher Ks values toward positively charged guests and lower Ks toward negatively charged guests than host 3. The 2D NMR spectra of hosts 3 and 5 with RhB were acquired to understand the binding difference between 3 and 5. The molecular binding ability and selectivity of model substrates by these hosts were sufficiently investigated to reveal not only the cooperative contributions of the linker group and CD cavities upon inclusion complexation with dye guest molecules, but also the controlling factors for the molecular selective binding. Copyright © 2008 John Wiley & Sons, Ltd.
Proximity effects of oxygen atoms on the enthalpies of formation of simple diethers: a computational G3(MP2)//B3 study
Authors: Taskinen Esko , Taskinen Antti
Published: May 2008

The enthalpies of formation of a number of acyclic, straight‐chain ethers and diethers were determined by G3(MP2)//B3 calculations. The principal aim of the work was to study the magnitude of the O…O proximity effect on the enthalpy contents of diethers as a function of the distance (number of bonds) between the O atoms. 1,4‐Diethers and 1,5‐diethers were computed to be destabilized byca. 4.5 (±0.5) and 3.2 (±0.4) kJ mol−1, respectively, by the O…O proximity effect. The effect was calculated to be negligible in diethers with the O atoms in positions more remote than 1,5 from each other, whereas 1,3‐diethers (acetals) are stabilized byca. 22 kJ mol−1, likely on account of the anomeric effect. Calculations on simple monoethers show that the contributions to$\Delta_{\rm f} H^{\circ}_m$of CH2groups in theβandγpositions (relative to O) are reduced byca. 0.8 and 0.3 kJ mol−1, respectively, relative to those of CH2groups more remote from the O atom. The computational enthalpies of formation of the studied monoethers and diethers, both cyclic and acyclic, are generally in good agreement with experimental data, another important result of the present work. Copyright © 2008 John Wiley & Sons, Ltd.
A combined experimental and theoretical study of the alkylation of 3,5‐dithioxo‐[1,2,4]triazepines
Authors: Esseffar M. , El Messaoudi M. , Jalal R. , Domingo L. R. , Aurell M. J.
Published: May 2008

The chemo‐ and regioselective alkylation reactions of 3,5‐dithioxo[1,2,4]triazepine 1 in a basic medium with α,ω‐dibromoalkanes 2a–c, Br(CH2)nBr (n = 1–3), are studied experimentally and theoretically. These alkylations, which occur at the thioxo sulfur atom in position 5, afford mainly 5‐bromomethylthio‐2,7‐dimethyl‐ 2,3‐dihydro‐ 4H[1,2,4]triazepin‐3‐one 3 for n = 1, 6,8‐dimethyl‐5‐thioxo‐2,3,4,5‐tetrahydro‐6H[1,3]thiazolo[4,5‐d][1,2,4]triazepine 4 for n = 2 and 7,9‐dimethyl‐6‐thioxo‐2,3,4,5,6,7‐hexahydro[1,3]thiazino [4,5‐d][1,2,4]triazepine 5 for n = 3. Theoretical calculations have been carried out at the B3LYP/6‐31G* and B3LYP(benzene)/6‐311+G*//B3LYP/6‐31G* levels, in order to rationalize the experimental observations. Both chemo‐ and regio‐selectivities of the alkylation reactions are analyzed. Copyright © 2008 John Wiley & Sons, Ltd.
Thioenols and thioamides substituted by two β‐EWGs. Comparison with analogous amides and enols
Authors: Basheer Ahmad , Rappoport Zvi
Published: May 2008

Condensation of organic isothiocyanates with active methylene compounds gave nine thioamides RNHCSCHYY′ or their isomeric thioenols RNHC(SH) = CYY′ for substrates in which Y and Y′ are electron‐withdrawing groups (EWG). These included derivatives of Meldrum's acid (MA) which showed 100% thioenol in all solvents. For other compounds the percentages of thioenol in CDCl3 when R = Ph are 100% when Y = CN and Y′ = CO2Me or Y′ = CO2CH2CCl3, 6% when Y = Y′ = CO2CH2CF3, and 0% when Y = Y′ = CO2Me. The chemical shift of SH (highest values 12.0–16.0 ppm) served as a probe for the thioenol structures and also for the extent of hydrogen bonding to the SH group. In contrast to simple ketones and thioketones in which thioenolization is favored over enolization by factors as large as 106, for intramolecular competition KThioenol/KEnol ratios are much lower than for systems not substituted by β‐EWGs. X‐ray crystallography of the 5‐anilido‐MA derivative shows a hydrogen‐bonded thioenol structure. δ(OH), δ(NH), KEnol, and crystallographic data for analogous thioenol and enol systems are compared. Copyright © 2008 John Wiley & Sons, Ltd.