[Molecular epidemiological study on rubella virus circulating in Yunnan Province during 2011-2021].

Objective: To understand the genotype distribution and transmission pattern of rubella virus (RuV) circulating in Yunnan Province. Methods: Throat swab samples were collected from rubella outbreaks and sporadic cases in nine prefectures/cities of Yunnan Province from 2011 to 2021. Virus isolation, amplification of target genes and sequence determination were performed on the RuV-positive samples. The genotypes and lineages of Yunnan strains were determined by comparing them with the reference strains, and further phylogenetic analysis was performed with Yunnan strains and strains circulating in other provinces of China during the same period. Results: RuV circulating in Yunnan province during 2011-2021 showed significant genetic diversity, and three lineages, 1E-L1, 2B-L1 and 1E-L2, were detected. Two lineage-switches were also identified, including the conversion of 1E-L1 to 2B-L1 between 2012 and 2013, and the replacement of 2B-L1 to 1E-L2 after 2018. The time of the switches was basically consistent with the outbreak in Yunnan province in 2012 and the time of the rubella reemergence and epidemic between 2018 and 2019. The amino acid sequence of RuV virus strains in Yunnan province was highly conserved, and no important functional regions were changed. Conclusions: The transmission pattern of RuV in Yunnan province is generally consistent with the epidemic trend of RuV in other provinces of China.

[Expression of glycolytic genes in immune cells and changes of related immune cells in experimental autoimmune neuritis].

Objective: To investigate the expression of glycolytic genes in immune cells and the changes of related immune cells in experimental autoimmune neuritis (EAN), and deepen the understanding of pathogenesis of EAN. Methods: Twenty-four male C57BL/6 mice (6-8 weeks old, 18-20 g) were divided into four groups according to the random number table method: control group (P0180-199 was replaced by PBS during modeling and mice were sacrificed on the 16th day), EAN mice were sacrificed on the 8th day after the end of modeling (EAN 8 d), EAN mice were sacrificed on the 16th day after the end of modeling (EAN 16 d), and EAN mice received drug intervention and were sacrificed on the 16th day after the end of modeling (2-DG was intraperitoneally injected since the day of the first immunization, 550 mg/kg; EAN 16 d+2-DG), with 6 rats in each group. The clinical symptoms and clinical scores were observed and recorded daily. At the end of the experiment, the mice were sacrificed under chloral hydrate anesthesia, and the serum, spleen, sciatic nerve and other tissues of each group were collected. The degree of inflammatory cell infiltration and demyelination of sciatic nerve were observed by hematoxylin and eosin (HE) staining and luxol fast blue (LFB) staining. Flow cytometry was used to detect the proportion of M1 macrophages, Th17 cells and Tregs cells. The mRNA expression levels of glycolysis-related genes (mTORC1, HIF1α, GLUT1 and LDHA) were detected by RT-PCR. Western blotting was used to detect the level of pan-lysine lactate in macrophages and sciatic nerve tissue. Results: The expression of glycolysis-related genes (mTORC1, HIF1α, GLUT1 and LDHA) in spleen M1 macrophages and sciatic nerve was significantly up-regulated in EAN 16 d group, compared with control, EAN 8 d and EAN 16 d+2-DG groups (all P<0.05). The relative pan-lysine lactate (pankla) expression level of spleen M1 macrophages (1.25±0.02) and sciatic nerve tissue (1.23±0.26) significantly increased in EAN 16 d group, compared with control, EAN 8 d and EAN 16 d+2-DG groups (M1 macrophages: 0.12±0.10, 1.07±0.12 and 0.42±0.07; sciatic nerve: 0.10±0.12, 0.87±0.20 and 0.36±0.05) (all P<0.05). The expression of glycolytic genes in splenic CD4+T cells showed an increasing trend, but there were no statistically significant differences among the groups, and the expression of glycolytic genes did not decrease significantly after 2-DG treatment (all P>0.05). The proportion of spleen M1 macrophages in the control group, EAN 8 d group, EAN 16 d group and EAN 16 d+2-DG group was 4.28±0.13, 7.54±0.25, 13.16±0.33 and 4.13±0.38 respectively, which was significantly higher in the EAN 16 d group (all P<0.05). The proportion of spleen Th17 cells in the four groups was 3.78±0.03, 8.24±0.55, 12.30±1.34 and 4.83±0.01, respectively, which was significantly higher in the EAN 16 d group (all P<0.05). The proportion of spleen Tregs cells in the four groups was 10.01±1.05, 7.54±0.70, 3.82±0.47 and 8.22±1.21, respectively, which was significantly lower in the EAN 16 d group (all P<0.05). Conclusions: The expression of glycolytic genes in splenic macrophages significantly increases during EAN, but not in CD4+T cells. The proportion of M1 macrophages and Th17 cells in spleen gradually increases, while the proportion of Tregs cells gradually decreases.

Altered neural activation pattern during teeth clenching in temporomandibular disorders.

OBJECTIVE: The aim was to explore the neural activations during teeth clenching in TMDs patients pre- and post-treatment. SUBJECTS AND METHODS: Thirty TMDs patients and 20 controls underwent clinical evaluations and functional magnetic resonance imaging with a teeth clenching task. Eleven patients received repeat evaluation and imaging after wearing a stabilization splint for 3 months. RESULTS: During teeth clench, the TMDs patients showed decreased positive activity in the left precentral gyrus, right and left inferior temporal gyrus, and left cerebellum and increased negative activations in the right medial prefrontal cortex (P < 0.05 after AlphaSim correction). The 11 TMDs patients after treatment showed a return to normal neural activity in these areas. No brain areas in TMDs patients showed differences in activation after treatment compared with the controls, except for an increase in activation in the right cerebellum in the 11 TMDs patients (P < 0.05 after AlphaSim correction). CONCLUSION: Decreased activations in cerebral areas associated with motor and cognitive functions in TMDs patients during teeth clenching were observed. Normalized activations of these areas happened in patients after routine treatment. These findings may facilitate the understanding of TMDs pathogenesis and the therapeutic mechanisms of the stabilization splint.

A quantitative analysis of (1)H-MR spectroscopy at 3.0 T of three brain regions from childhood to middle age.

OBJECTIVE: To study age-related metabolic changes in different brain regions. METHODS: Point-resolved spectroscopy (repetition time/echo time = 2000 ms/30 ms) was performed in the left and right hippocampus, the left thalamus and the left centrum semiovale of 80 healthy subjects (37 females and 43 males aged 7-64 years). Analysis of covariance and linear regression were used for statistical analysis. Both metabolite concentration ratios with respect to total creatine (tCr) and absolute metabolite concentrations were included for analysis. RESULTS: Ins (myo-inositol)/tCr (p < 0.001) and absolute Ins concentration (p = 0.031) were significantly increased with age after adolescence. NAA (N-acetylaspartic acid)/tCr (p < 0.001) and absolute NAA concentration (p = 0.010) significantly declined with age after adolescence. CONCLUSION: Age-related increase of Ins and decline of NAA are found in all three regions, especially at the hippocampus, indicating possible gliosis in the ageing brain. ADVANCES IN KNOWLEDGE: We could use NAA/tCr and Ins/tCr as an indicator to estimate the neurons-to-glial cells ratio at the thalamus. This may be an index to distinguish normal tissues from gliosis.

Development and validation of a Chinese outpatient satisfaction questionnaire: evidence from 46 public general hospitals and 5151 outpatients.

OBJECTIVE: To develop and test a reliable and practical self-administrated questionnaire in Chinese to evaluate outpatient satisfaction in China. DESIGN: In order to ensure content validity, the 19 items of this questionnaire were generated based on literature review, interview and group discussion. Acceptability was tested by the percentage of missing item responses and the time and operability of administration. Construct validity was evaluated using principal component exploratory factor analysis and item-total correlations. The reliability of the questionnaire was assessed using Cronbach's alpha coefficient and inter-subscale correlation. SETTING: This study was conducted in 46 public general hospitals that report directly to the Provincial Health Department in Hunan Province, China. SUBJECTS: In total, 5151 outpatients were selected at random and asked to complete the questionnaire after they finished their medical procedures in the outpatient area. RESULTS: The extremely low rate of missing data (0-0.04%) suggested good acceptability of the questionnaire. Factor analysis generated six dimensions, and all item-total coefficients were >0.8. Cronbach's alpha exceeded 0.7 for all dimensions, and the inter-subscale correlation coefficients were all lower than the Cronbach's alpha coefficients of the corresponding scale. According to the results, outpatients were least satisfied with waiting time (86.8%) and most satisfied with the quality of medical care (90.1%). CONCLUSION: The Chinese outpatient satisfaction questionnaire has good acceptability, validity and reliability. It was effective and efficient for measuring outpatient satisfaction in a Chinese population.

Spontaneous neural activity alterations in temporomandibular disorders: a cross-sectional and longitudinal resting-state functional magnetic resonance imaging study.

The involvement of the central nervous system in the pathophysiology of temporomandibular disorders (TMD) has been noticed. TMD patients have been shown dysfunction of motor performance and reduced cognitive ability in neuropsychological tests. The aim of this study is to explore the spontaneous neural activity in TMD patients with centric relation (CR)-maximum intercuspation (MI) discrepancy before and after stabilization splint treatment. Twenty-three patients and twenty controls underwent clinical evaluations, including CR-MI discrepancy, Helkimo indices and chronic pain, and resting state functional magnetic resonance imaging scans at baseline. Eleven patients repeated the evaluations and scanning after the initial wearing (T1) and 3months of wearing (T2) of the stabilization splint. The fractional amplitude of low-frequency fluctuation (fALFF) was calculated to compare the neural functions. At baseline, the patients showed decreased fALFF in the left precentral gyrus, supplementary motor area, middle frontal gyrus and right orbitofrontal cortex compared with the controls (P<0.05, AlphaSim corrected). Negative correlations were found between the fALFF in the left precentral gyrus and vertical CR-MI discrepancy of bilateral temporomandibular joints of patients (P<0.05, two-tailed). At T2, the symptoms and signs of the patients were improved, and a stable condylar position on the CR was recovered, with increased fALFF in the left precentral gyrus and left posterior insula compared with pretreatment. The fALFF decrease in the patients before treatment was no longer evident at T2 compared with the controls. The results suggested that TMD patients with CR-MI discrepancy showed significantly decreased brain activity in their frontal cortexes. The stabilization splint elicited functional recovery in these cortical areas. These findings provided insight into the cortical neuroplastic processes underlying TMD with CR-MI discrepancy and the therapeutic mechanisms of stabilization splint.

Brain grey matter abnormalities in medication-free patients with major depressive disorder: a meta-analysis.

BACKGROUND: Because cerebral morphological abnormalities in major depressive disorder (MDD) may be modulated by antidepressant treatment, inclusion of medicated patients may have biased previous meta-analyses of voxel-based morphometry (VBM) studies. A meta-analysis of VBM studies on medication-free MDD patients should be able to distinguish the morphological features of the disease itself from those of treatment. METHOD: A systematic search was conducted for the relevant studies. Effect-size signed differential mapping was applied to analyse the grey matter differences between all medication-free MDD patients and healthy controls. Meta-regression was used to explore the effects of demographics and clinical characteristics. RESULTS: A total of 14 datasets comprising 400 medication-free MDD patients and 424 healthy controls met the inclusion criteria. The pooled meta-analysis and subgroup meta-analyses showed robustly reduced grey matter in prefrontal and limbic regions in MDD. Increased right thalamus volume was only seen in first-episode medication-naive patients, and increased grey matter in the bilateral anterior cingulate cortex only in medication wash-out patients. In meta-regression analyses the percentage of female patients in each study was negatively correlated with reduced grey matter in the right hippocampus. CONCLUSIONS: By excluding interference from medication effects, the present study identified grey matter reduction in the prefrontal-limbic network in MDD. The subgroup meta-analysis results suggest that an increased right thalamus volume might be a trait directly related to MDD, while an increased anterior cingulate cortex volume might be an effect of medication. The meta-regression results perhaps reveal the structural underpinning of the sex differences in epidemiological and clinical aspects of MDD.

Can diffusion-weighted imaging be used to differentiate brain abscess from other ring-enhancing brain lesions? A meta-analysis.

AIM: To explore the role of diffusion-weighted imaging (DWI) in the discrimination of brain abscess from other ring-enhancing brain lesions through meta-analysis. MATERIALS AND METHODS: The PUMBED, OVID, and China National Knowledge Infrastructure (CNKI) databases, from January 1995 to March 2013, were searched for studies evaluating the diagnostic performance of DWI in the discrimination of brain abscess lesions. Using the data collected, pooled sensitivities and specificities across studies were determined, positive and negative likelihood ratios (LR) were calculated, and summary receiver operating characteristic (SROC) curves were constructed. RESULTS: A total of 11 studies fulfilled all of the inclusion criteria and were considered for the analysis. The pooled sensitivity values and pooled specificity values including 95% confidence intervals (CI) were 0.95 (0.87-0.98) and 0.94 (0.88-0.97). The pooled positive LR (95% CI) was 4.13(2.55-6.7); the pooled negative LR (95% CI) was 0.01 (0-1.7); and the area under the curve of the symmetric SROC was 0.98. CONCLUSIONS: DWI has high sensitivity and specificity for the differentiation of brain abscess from other intracranial cystic mass lesions.

Plasmid encoding matrix protein of vesicular stomatitis viruses as an antitumor agent inhibiting rat glioma growth in situ.

AIM: Oncolytic effect of vesicular stomatitis virus (VSV) has been proved previously. Aim of the study is to investigate glioma inhibition effect of Matrix (M) protein of VSV in situ. MATERIALS AND METHODS: A recombinant plasmid encoding VSV M protein (PM) was genetically engineered, and then transfected into cultured C6 gliomas cells in vitro. C6 transfected with Liposome-encapsulated PM (LEPM) was implanted intracranially for tumorigenicity study. In treatment experiment, rats were sequentially established intracranial gliomas with wild-typed C6 cells, and accepted LEPM injection intravenously. Possible mechanism of M protein was studied by using Hoechst staining, PI-stained flow cytometric analysis, TUNEL staining and CD31 staining. RESULTS: M protein can induce generous gliomas lysis in vitro. None of the rats implanted with LEPM-treated cells developed any significant tumors, whereas all rats in control group developed tumors. In treatment experiment, smaller tumor volume and prolonged survival time was found in the LEPM-treated group. Histological studies revealed that possible mechanism were apoptosis and anti-angiogenesis. CONCLUSION: VSV-M protein can inhibit gliomas growth in vitro and in situ, which indicates such a potential novel biotherapeutic strategy for glioma treatment.

Item recognition is less impaired than recall and associative recognition in a patient with selective hippocampal damage.

This article explores the recall, item recognition, and associative recognition memory of patient B.E., whose pattern of retrograde amnesia was reported by Kapur and Brooks (1999; Hippocampus 9:1-8). Structural magnetic resonance imaging (MRI) has shown that B.E. has bilateral damage restricted to the hippocampus. The structural damage he had sustained was accompanied by bilateral hypoperfusion of the temporal lobe, revealed by positron emission tomography (PET), and which single photon emission computed tomography (SPECT) suggested was greater in the left than the right temporal lobe. B.E. showed a global anterograde amnesia for verbal material, but he displayed some sparing of nonverbal item recognition relative to nonverbal recall and associative recognition. His performance on an item recognition task that used the remember/know procedure and another that involved repetition of the test phase, to reduce the difference between the familiarity of the targets and foils, suggested that his relatively spared nonverbal item recognition may have been mainly supported by familiarity. This finding is consistent with the view that the anterior temporal lobe, including the perirhinal cortex, can support familiarity-based memory judgments (Brown and Bashir, 2002; Philos Trans R Soc Lond B 357:1083-1095). B.E.'s data also highlight the importance of functional as well as structural scan information for interpreting the pattern of memory deficits shown by patients with selective hippocampal structural lesions.

Quantification of tumour response to radiotherapy.

In 1979, the World Health Organization (WHO) established criteria based on tumour volume change for classifying response to therapy as (i) progressive disease (PD), (ii) partial recovery (PR), and (iii) no change (NC). Typically, the tumour volume is reported from diameter measurements, using the calliper method. Alternatively, the Cavalieri method provides unbiased volume estimates of any structure without assumptions about its shape. In this study, we applied the Cavalieri method in combination with point counting to investigate the changes in tumour volume in four patients with high grade glioma, using 3D MRI. In particular, the volume of tumour within the enhancement boundary, the enhancing abnormality (EA), was estimated from T(1) weighted images, and the volume of the non-enhancing abnormality, (NEA) enhancing abnormality, was estimated from T(2) relaxation time and magnetic transfer ratio tissue characterization maps. We compared changes in tumour volume estimated by the Cavalieri method with those obtained using the calliper method. Absolute tumour volume differed significantly between the two methods. Analysis of relative change in tumour volume, based on the WHO criteria, provided a different classification using the calliper and Cavalieri methods. The benefit of the Cavalieri method over the calliper method in the estimation of tumour volume is justified by the following factors. First, Cavalieri volume estimates are mathematically unbiased. Second, the Cavalieri method is highly efficient under an appropriate sampling density (i.e. EA volume estimates can be obtained with a coefficient of error no higher than 5% in 2-3 min). Third, the source of variation of the volume estimates due to disagreements between observers, and within observer, is much greater in the positioning of the calliper diameters than in the identification of the tumour boundaries when applying the Cavalieri method. Additionally, the error prediction formula, available to estimate the coefficient of error of Cavalieri volume estimates from the data, allows us to establish more precise classification criteria against which to identify potentially clinical significant changes in tumour volume.

Remembering and knowing in a patient with preserved recognition and impaired recall.

ROB is a patient who has a severe deficit in recalling recently presented verbal material following rupture and repair of an anterior communicating artery aneurysm [Hanley JR, Davies ADM, Downes J, Mayes A. Cognitive Neuropsychology 1994;11:543-78; Hanley JR, Davies ADM. In: Parkin A, editor. Case Studies in the Neuropsychology of Memory. Hillsdale, NJ: Lawrence Erlbaum, 1997. p. 111-26]. Despite this, her performance on tests of recognition memory is comfortably within the normal range. In the present series of experiments, we investigated whether or not ROB's performance on tests of recognition memory might be associated with a disproportionately large number of correct decisions made on the basis of familiarity rather than contextual retrieval [e.g. Mandler G. Psychological Review 1980;87:252-71]. Contrary to this hypothesis, the results showed that ROB made a high proportion of remember decisions relative to know decisions in recognition [cf. Gardiner JM. Memory & Cognition 1988;16:309-13] and produced a high recollection score when conscious recollection and familiarity were placed in opposition to one another [cf. Jacoby LL, Woloshyn V, Kelley C. Journal of Experimental Psychology: General 1989;118:115-25.]. ROB's recognition memory performance therefore appears to be qualitatively as well as quantitatively similar to that found in the normal population. As ROB has suffered damage to both the fornix and the anterior thalamus, the results of the present study are consistent with the claim that damage to the extended hippocampal system has a much more severe effect on recall than on recognition [Aggleton JP, Shaw C. Neuropsychologia 1996;34:51-62; Aggleton JP, Saunders RC. Memory 1997;5:49-71]. The present results provide no support, however, for the additional suggestion [Aggleton JP, Brown MW. Behavioral and Brain Sciences 1999;22:425-56.] that the extended hippocampal system is necessary for recognition memory decisions that are based on contextual retrieval.

Estimation of body composition in muscular dystrophy by MRI and stereology.

We have applied the Cavalieri method of modern design stereology with magnetic resonance imaging for estimating the volume of whole-body muscle and fat compartments in four patients with muscular dystrophy, a patient with myopathy, five controls, an anorexic subject, and a body builder. Detailed systematic series (ie, 50) of axial MR images (T1-weighted, TR/TE 400/10 msec) were obtained throughout the whole body of each subject. The results showed that 15, 20, and 35 axial sections through the body are sufficient to secure coefficients of error (CEs) on the estimates of total muscle and fat volume of around 10%, 5%, and 3% respectively in muscular dystrophy patients and controls. The mean normalized volumes of muscle in four muscular dystrophy patients were decreased by 27% (t-test: P < 0.05), and those of total fat were increased by 12% (t-test: P > 0.05) relative to controls. The Cavalieri method provides a direct, efficient, and mathematically unbiased approach for studying human body compartments and may have application in assessing treatment efficacy in patients with muscular dystrophy. J. Magn. Reson. Imaging 2000;12:467-475.

Interaction of combined administration of intrathecal morphine with subcutaneous morphine or buprenorphine.

AIM: To analyze the mode of interaction of combined administration of intrathecal morphine with subcutaneous morphine or buprenorphine. METHODS: Different groups of rats were scheduled to undergo administration of intrathecal (ith) morphine, subcutaneous (s.c.) morphine, s.c. buprenorphine, and the combinations of ith morphine with s.c. morphine or buprenorphine in a series of dose ratios. Nociceptive responses of hind paws of each animal were measured by means of "plantar stimulation" test. The test latency was converted to the percent of maximal possible effect (% MPE). RESULT: Morphine ith, morphine s.c., buprenorphine s.c., as well as combinations in all dose ratios increased the % MPE in a dose-dependent manner. Isobolograms showed that the ED50 points determined for the combinations were plotted significantly left to the theoretical additive line. CONCLUSION: The combination of morphine ith with either morphine s.c. or buprenorphine s.c. resulted in a synergistic effect. This interaction might be due to the activation of the synergistic antinociceptive mechanisms between supraspinal and spinal levels.

Effects of catalase and endothelin on anoxia-induced vasoconstriction of porcine basilar artery in vitro.

AIM: To study whether anoxia-induced vasoconstriction was related to the release of endothelin (ET). METHODS: Acute anoxia was induced by gassing the organ chamber with 95% N2 + 5% CO2. Changes in tension of porcine basilar arterial ring was recorded. RESULTS: Anoxia-induced increases in tension were 0.21 g +/- 0.08 g and 0.24 g +/- 0.09 g under basal tension and during ET 3 nmol.L-1-induced contractions, respectively. In the rings tension did not further augment following the increase of ET from 100 to 300 nmol.L-1, acute anoxia did cause further increase in tension of 0.16 g +/- 0.10 g (n = 4). Catalase 800 and 2400 kU.L-1 decreased the anoxia-induced contraction, with inhibitory rate of 33% +/- 7% and 47% +/- 9%, respectively. CONCLUSION: Anoxia-induced vasoconstriction was related to release of hydrogen peroxide from endothelial cells.

Determination of tumour regression rates during radiotherapy for cervical carcinoma by serial MRI: comparison of two measurement techniques and examination of intraobserver and interobserver variability.

Tumour regression rates of 11 patients with cervical carcinoma were estimated during external beam radiotherapy (EBRT) using serial MRI (average time interval 7 days; range 3-15 days). An average of five investigations (range 4-8) was performed per subject. Tumour volume was measured by two observers using the Cavalieri method of modern design stereology in combination with (a) planimetry and (b) point counting. The mean precision of all the volume estimates obtained by manually tracing the outline of the tumour was 6.6%. The mean precision obtained by counting an average of 176 points per investigation on the same transects was 6.7%. The intraobserver repeatability of planimetry, interobserver reproducibility of planimetry and point counting were excellent with no significant difference between the volume estimates obtained using either technique. Based on the planimetry measurements, initial tumour volumes ranged from 6.5 to 222 cm3 (mean 63 cm3, median 44 cm3). Based on the point counting measurements, initial tumour volumes ranged from 7.2 to 235 cm3 (mean 68 cm3, median 46 cm3). Tumour regression began within a few days of commencing EBRT and showed an exponential relationship with time (p < 0.01). There was good agreement between the regression rates obtained by planimetry and those obtained by point counting. No significant correlation was found between initial tumour volume and tumour regression rate for either planimetry or point counting. Planimetry measurements were, on average, obtained in about half the time taken for point counting (i.e. 30 min and 50 min, respectively). Although point counting is generally likely to be the more efficient approach, planimetry may be the preferred approach for estimating tumour volume when a purpose built track ball is available and the tumour morphology is relatively simple. Volume measurement should be obtained using the Cavalieri method to ensure that the estimates are unbiased and that their precision can be predicted. The measured tumour regression rates may have important implications for improving local tumour control, optimum timing of brachytherapy and minimizing the risk of radiation damage.

Infratentorial atrophy on magnetic resonance imaging and disability in multiple sclerosis.

Loss of tissue volume in the central nervous system may provide an index of fixed neurological dysfunction in multiple sclerosis. Recent magnetic resonance studies have shown a modest relationship between clinical disability rating scores and transverse sectional area of the cervical spinal cord. To explore further the relationship between atrophy and disability in multiple sclerosis, we estimated the volumes of infratentorial structures from MRIs in a cross-sectional study of 41 patients, 21 with relapsing-remitting multiple sclerosis and 20 with secondary progressive multiple sclerosis. We used the Cavalieri method of modern design stereology with point counting to estimate the volume of brainstem, cerebellum and upper cervical spinal cord from three-dimensional MRIs acquired with an MPRAGE (Magnetization-prepared Rapid Acquisition Gradient Echo) sequence. The volume of the upper (C1-C3) cervical spinal cord was significantly correlated with a composite spinal cord score derived from the appropriate Functional Scale scores of the Expanded Disability Status Scale (r = -0.50, P < 0.01). The cerebellar (r = 0.49, P < 0.01) and brainstem (r = 0.34, P < 0.05) volumes correlated with the Scripp's Neurological Disability Rating Scale scores. The upper cervical cord volumes (r = -0.39, P < 0.01), but not the brainstem or cerebellar volumes, were significantly associated with disease duration. MRI-estimated structural volumes may provide a simple index of axonal and/or myelin loss, the presumed pathological substrates of irreversible impairment and disability in multiple sclerosis.

Contrast enhanced dynamic MRI of cervical carcinoma during radiotherapy: early prediction of tumour regression rate.

This prospective study investigated the relationship between changes in the MRI dynamic enhancement of cervical carcinoma early during radiotherapy, and tumour regression rate throughout radiotherapy. A total of 36 MRI examinations was performed in seven patients with cervical carcinoma, including a T2 weighted sequence weekly during radiotherapy and also a multislice dynamic Gd-DTPA enhanced sequence before and after the first 2 weeks of radiotherapy. Tumour enhancement was determined on dynamic images using a region of interest and signal-to-noise ratio method. Serial tumour volumes over time on T2 weighted images were estimated using the Cavalieri method of modern design-based stereology to obtain tumour regression rate. It was found that peak and mean enhancement prior to radiotherapy ranged from 3.0 to 13.3, and from 1.9 to 12.2, respectively. After 2 weeks of radiotherapy, peak and mean enhancement ranged from 7.5 to 13.0, and from 6.3 to 10.6, respectively. The change in peak and mean tumour enhancement between dynamic scans ranged, respectively, from -2.0 to 8.4 and from -4.5 to 8.5. Tumour volume decreased exponentially with time (p < 0.01). Tumour regression rates ranged from 2.0% to 15.2% per day, and correlated positively with changes of both peak and mean tumour enhancement (p < 0.01). It is concluded that MRI dynamic enhancement during the first 2 weeks of radiotherapy may provide early prediction of tumour regression rate, and therefore be of value in designing treatment schedules for cervical carcinoma.

Fetal and fetal brain volume estimation in the third trimester of human pregnancy using gradient echo MR imaging.

The Cavalieri method has been applied in combination with gradient echo magnetic resonance imaging (MRI) to investigate the increase in the volume of the fetus and fetal brain in the third trimester of pregnancy. Eighteen women with singleton pregnancies were recruited. Birthweights for the fetuses all lay within the 10-90th centile based on Liverpool data. A regression analysis, weighted using values derived from the coefficient of error predicted for each volume estimate, revealed a linear relationship between total fetal volume and gestational age (R2 = 0.88) and between fetal brain volume and gestational age (R2 = 0.71) during the third trimester. Fetal volume increased by an average of 25.2 ml per day and fetal brain volume increased by an average of 2.3 mL per day. Fetal brain volume is on average a constant proportion (10%, SD = 2%) of total fetal volume throughout the third trimester. Volume data were also obtained for eight fetuses diagnosed as abnormal. The volume of seven of the eight abnormal fetuses fell outside the 95% confidence interval established from the data obtained for the normal fetuses. However, for only three of the eight abnormal fetuses did brain volume fall outside the 95% confidence interval established for normals, possibly due to brain sparing occurring in asymmetrical growth retardation. The volume of the fetus and fetal brain may be readily estimated directly using the Cavalieri method and magnetic resonance imaging. These parameters represent potentially useful information for assessing fetal growth.

Electrophysiological effects of felodipine on guinea pig papillary muscles.

AIM: To determine whether felodipine (Fel) has Ca2+ channel blocking effect in mammalian myocardium in comparison with those of nifedipine (Nif) and verapamil (Ver). METHODS: The action potentials (AP), the slow AP and the inward slow Ca2+ currents of guinea pig papillary muscles were studied using intracellular microelectrodes and voltage-clamp techniques. RESULTS: Fel 1, 3, and 10 mumol.L-1 concentration-dependently shortened APD30, APD50, and APD90 of the AP, while Vmax and APA were not affected. The effect of Fel was not reversible on washout. At 0.1, 1, 3, and 10 mumol.L-1, Fel depressed Vmax, APA, APD30, APD50, and APD90 of the slow AP in a dose-dependent manner. The inward slow Ca2+ currents were reduced by Fel 3 mumol.L-1. APD30, APD50, and APD90 of the first AP after rest were still shortened by Fel. When the stimulation frequency was elevated, the effect of Fel on the AP and slow AP decreased. The effect of Fel 3 mumol.L-1 on the slow AP was abolished in preparation pretreated with trifluoperazine. The threshold concentrations of Nif and Ver for the inhibition of APD50 of the slow AP (P < 0.05) were 0.1 and 1 mumol.L-1, respectively. The effect of Ver 3 mumol.L-1 on the fast AP was not reversible on washout, but that of Nif 3 mumol.L-1 was. When the stimulation frequency was elevated from 0.5 to 2 Hz, the effect of Nif 3 mumol.L-1 on the fast AP was reduced, but that of Ver 3 mumol.L-1 was increased. CONCLUSION: Fel inhibited mainly the resting state of the cardiac Ca2+ channel. The potency of Fel was about the same as that of Nif and about 10 times more potent than that of Ver.