Application of 7T MRS to High-Grade Gliomas

MRS, including single-voxel spectroscopy and MR spectroscopic imaging, captures metabolites in high-grade gliomas. Emerging evidence indicates that 7T MRS may be more sensitive to aberrant metabolic activity than lower-field strength MRS. However, the literature on the use of 7T MRS to visualize high-grade gliomas has not been summarized. We aimed to identify metabolic information provided by 7T MRS, optimal spectroscopic sequences, and areas for improvement in and new applications for 7T MRS. Literature was found on PubMed using "high-grade glioma," "malignant glioma," "glioblastoma," "anaplastic astrocytoma," "7T," "MR spectroscopy," and "MR spectroscopic imaging." 7T MRS offers higher SNR, modestly improved spatial resolution, and better resolution of overlapping resonances. 7T MRS also yields reduced Cramér-Rao lower bound values. These features help to quantify D-2-hydroxyglutarate in isocitrate dehydrogenase 1 and 2 gliomas and to isolate variable glutamate, increased glutamine, and increased glycine with higher sensitivity and specificity. 7T MRS may better characterize tumor infiltration and treatment effect in high-grade gliomas, though further study is necessary. 7T MRS will benefit from increased sample size; reductions in field inhomogeneity, specific absorption rate, and acquisition time; and advanced editing techniques. These findings suggest that 7T MRS may advance understanding of high-grade glioma metabolism, with reduced Cramér-Rao lower bound values and better measurement of smaller metabolite signals. Nevertheless, 7T is not widely used clinically, and technical improvements are necessary. 7T MRS isolates metabolites that may be valuable therapeutic targets in high-grade gliomas, potentially resulting in wider ranging neuro-oncologic applications.

Structural MRI at 7T reveals amygdala nuclei and hippocampal subfield volumetric association with Major Depressive Disorder symptom severity

Subcortical volumetric changes in major depressive disorder (MDD) have been purported to underlie depressive symptomology, however, the evidence to date remains inconsistent. Here, we investigated limbic volumes in MDD, utilizing high-resolution structural images to allow segmentation of the hippocampus and amygdala into their constituent substructures. Twenty-four MDD patients and twenty matched controls underwent structural MRI at 7T field strength. All participants completed the Montgomery-Asberg Depression Rating Scale (MADRS) to quantify depressive symptomology. For the MDD group, volumes of the amygdala right lateral nucleus (p = 0.05, r2 = 0.24), left cortical nucleus (p = 0.032, r2 = 0.35), left accessory basal nucleus (p = 0.04, r2 = 0.28) and bilateral corticoamygdaloid transition area (right hemisphere p = 0.032, r2 = 0.38, left hemisphere p = 0.032, r2 = 0.35) each displayed significant negative associations with MDD severity. The bilateral centrocortical (right hemisphere p = 0.032, r2 = 0.31, left hemisphere p = 0.032, r2 = 0.32) and right basolateral complexes (p = 0.05, r2 = 0.24) also displayed significant negative relationships with depressive symptoms. Using high-field strength MRI, we report the novel finding that MDD severity is consistently negatively associated with amygdala nuclei, linking volumetric reductions with worsening depressive symptoms.

Dynamic Contrast-Enhanced MRI-Derived Intracellular Water Lifetime (τ i ): A Prognostic Marker for Patients with Head and Neck Squamous Cell Carcinomas

BACKGROUND AND PURPOSE

Shutter-speed model analysis of dynamic contrast-enhanced MR imaging allows estimation of mean intracellular water molecule lifetime (a measure of cellular energy metabolism) and volume transfer constant (a measure of hemodynamics). The purpose of this study was to investigate the prognostic utility of pretreatment mean intracellular water molecule lifetime and volume transfer constant in predicting overall survival in patients with squamous cell carcinomas of the head and neck and to stratify p16-positive patients based upon survival outcome.

MATERIALS AND METHODS

A cohort of 60 patients underwent dynamic contrast-enhanced MR imaging before treatment. Median, mean intracellular water molecule lifetime and volume transfer constant values from metastatic nodes were computed from each patient. Kaplan-Meier analyses were performed to associate mean intracellular water molecule lifetime and volume transfer constant and their combination with overall survival for the first 2 years, 5 years, and beyond (median duration, >7 years).

RESULTS

By the last date of observation, 18 patients had died, and median follow-up for surviving patients (n = 42) was 8.32 years. Patients with high mean intracellular water molecule lifetime (4 deaths) had significantly (P = .01) prolonged overall survival by 5 years compared with those with low mean intracellular water molecule lifetime (13 deaths). Similarly, patients with high mean intracellular water molecule lifetime (4 deaths) had significantly (P = .006) longer overall survival at long-term duration than those with low mean intracellular water molecule lifetime (14 deaths). However, volume transfer constant was a significant predictor for only the 5-year follow-up period. There was some evidence (P < .10) to suggest that mean intracellular water molecule lifetime and volume transfer constant were associated with overall survival for the first 2 years. Patients with high mean intracellular water molecule lifetime and high volume transfer constant were associated with significantly (P < .01) longer overall survival compared with other groups for all follow-up periods. In addition, p16-positive patients with high mean intracellular water molecule lifetime and high volume transfer constant demonstrated a trend toward the longest overall survival.

CONCLUSIONS

A combined analysis of mean intracellular water molecule lifetime and volume transfer constant provided the best model to predict overall survival in patients with squamous cell carcinomas of the head and neck.

Association and expression of the antigen-processing gene PSMB8, coding for low-molecular-mass protease 7, with vitiligo in North India: case-control study

BACKGROUND

Vitiligo is a multifactorial, autoimmune, depigmenting disorder of the skin where aberrant presentation of autoantigens may have a role.

OBJECTIVES

To study the association of two antigen-processing genes, PSMB8 and PSMB9, with vitiligo.

METHODS

In total 1320 cases of vitiligo (1050 generalized and 270 localized) and 752 healthy controls were studied for the PSMB9 exon 3 G/A single-nucleotide polymorphism (SNP), PSMB8 exon 2 C/A SNP and PSMB8 intron 6 G/T SNP at site 37 360 using polymerase chain reaction (PCR)-restriction fragment length polymorphism. Real-time PCR was used for transcriptional expression of PSMB8 and cytokines. Expression of ubiquitinated proteins and phosphorylated-p38 (P-p38) was studied by Western blotting.

RESULTS

Significant increases in PSMB8 exon 2 allele A (P < 2.07 × 10^-6 , odds ratio 1·93) and genotypes AA (P < 1.03 × 10^-6 , odds ratio 2·51) and AC (P < 1.29 × 10^-6 , odds ratio 1·63) were observed in patients with vitiligo. Interferon-γ stimulation induced lower expression of PSMB8 in peripheral blood mononuclear cells of cases compared with controls, suggesting impaired antigen processing, which was confirmed by accumulation of ubiquitinated proteins in both lesional and nonlesional skin of patients with vitiligo. Expression of proinflammatory cytokines - interleukin (IL)-6, IL-1β and IL-8 - was higher in the lesional skin. P-p38 expression was variable but correlated with the amount of ubiquitinated proteins in the lesional and nonlesional skin, suggesting that the inflammatory cytokine responses in lesional skin could be a result of both P-p38-dependent and -independent pathways.

CONCLUSIONS

The PSMB8 exon 2 SNP is significantly associated with vitiligo. Accumulation of ubiquitinated proteins in skin of cases of vitiligo suggests their aberrant processing, which may promote the development of the disease.

Nasopharyngeal teratoma, congenital diaphragmatic hernia and Dandy-Walker malformation - a yet uncharacterized syndrome

An association of congenital diaphragmatic hernia, dandy walker malformation and nasopharyngeal teratoma is very rare. Here, we report a fourth case with this association where chromosomal microarray and whole exome sequencing (WES) was performed to understand the underlying genetic basis. Findings of few variants especially a novel variation in HIRA provided some insights. An association of congenital diaphragmatic hernia, dandy walker malformation and nasopharyngeal teratoma is very rare. Here, we report a fourth case with this association where chromosomal microarray and whole exome sequencing (WES) was performed to understand the underlying genetic basis. Findings of few variants especially a novel variation in HIRA provided some insights.

Sexual practices, myths and misconceptions among long distance truck drivers in North India

BACKGROUND

Long distance truck drivers and helpers constitute a high risk group for human immunodeficiency virus /acquired immune deficiency syndrome (HIV/AIDS). Despite increasing awareness of HIV/AIDS and safe sex practices, they still have a high incidence of new cases of HIV.

AIMS

This study carried out at an ART (anti-retroviral treatment) centre in North India aimed to evaluate the sexual myths and misconceptions prevalent among long distance drivers and helpers.

DESIGN

This was a retrospective study carried out at apex ART centre.

METHODS

Data were collected retrospectively from ART records of 129 long distance Truck drivers and 68 helpers. Details of socio-demographic characteristics, contact with commercial sex workers (CSW'S), pattern of condom usage with CSW'S and factors influencing it were studied.

RESULTS

We found that a significant number of drivers and helpers had sexual contact with CSW's and out of these, 30% of drivers and 50% of helpers reported not using condoms and instead resorting to methods like washing genitalia after sex with battery water/urine to avoid getting HIV. There was no significant relationship between pattern of condom usage and educational status, marital status and age. We also found that certain myths like sex with young CSW's was less likely to cause sexually transmitted diseases (STD's) and HIV were also widespread.

CONCLUSION

Owing to continuing prevalence of such sexual myths, long distance truck drivers and helpers do not use condoms while having sex with CSW's as they feel that they can enjoy sex with CSW's and still stay protected against STD's/HIV. It is imperative that this battery water/urine antiseptic myth be specifically targeted for better HIV control in this high risk group.

Facial lupus vulgaris of bilateral periorbital skin and conjunctiva: a case report and brief review

A 22-year-old male presented to the Dermatology Department with bilateral plaque lesions distributed symmetrically over malar area, bridge of nose and upper eyelids progressing over 1 year 3 months. Lesion remained unhealed after antibiotic treatment. Microscopy and culture for fungal and mycobacterial infections were negative. The Mantoux test showed an exaggerated response and PCR was positive for Mycobacterium tuberculosis complex. Patient was treated successfully with anti-tubercular therapy.

Tuberculosis screening for long-term care: a cost-effectiveness analysis

SETTING

Long-term care facilities in Canada, a low tuberculosis (TB) incidence country.

OBJECTIVE

To compare the impact and cost-effectiveness of three screening strategies for TB on entry to long-term care: no screening, screening for latent tuberculous infection (LTBI) using the tuberculin skin test (TST) or screening for active disease with a chest X-ray.

DESIGN

Cost effectiveness analysis.

RESULTS

With the LTBI screening strategy, the number needed to screen to prevent one active case was 1410 and the cost per case averted was Canadian $109 913. The number needed to screen to prevent one case using the active screening strategy was 1266, and the cost per case averted was $672 298.

CONCLUSIONS

Our findings suggest that TB screening strategies on entry to long-term care are costly, with large numbers needed to screen. Screening with TST was more cost-effective than chest X-ray screening. Higher risk of reactivation of LTBI is associated with improved cost-effectiveness of screening. Short time horizons and test performance characteristics place limitations on screening programmes in this setting. Future considerations include the changing demographics of the institutionalised elderly.

Internal dynamics in SDS micelles: neutron scattering study

The molecular dynamics of sodium dodecyl sulfate (SDS) micelle has been investigated using high-resolution incoherent quasielastic neutron scattering technique. Data analysis clearly shows presence of two distinct motions: whole micellar motion or global diffusion and faster internal motion of the SDS monomer. The global diffusion associated with the whole micelle is found to be Fickian in nature, and the corresponding diffusion coefficients are found to be consistent with those obtained from dynamic light scattering measurements. The internal motion is described with a model consistent with the structure of the micelle and which accounts for the flexibility of the chains. The SDS monomer consists of a head group, which lies on the surface of the globular micelle, and a tail that hangs from the head toward the center of the globule. Considering various factors like conformational changes of the SDS chains, bending, stretching of the chemical bonds, etc., the dynamics of the SDS molecules is successfully described by a model in which the hydrogen atoms undergo localized translational motion confined within spherical volumes. This volume increases linearly along the SDS chain such that the hydrogen atoms closer to the head group move within smaller spheres with lower diffusion constant than the hydrogen atoms away from the head group. This model is found to be consistent with the data over the whole temperature and concentration range. Diffusivity and the volume of the spheres are also found to increase with temperature. The effect of lowering the SDS concentration is found to be similar to that of increasing the temperature.

Analysis of the mass media coverage of the Gates Foundation grand challenges in global health initiative

The Grand Challenges were launched in 2003 by the Gates Foundation and other collaborators to address the health needs of developing countries. This paper outlines the current problem with health research and development in the context of inequality as conveyed by the 90/10 divide. The paper then looks at the focus and nature of press reporting of global health issues by analysing how press articles have portrayed the Grand Challenges in Global Health initiative. Analysis of the mass media illustrates that the focus of reporting on the Grand Challenges tends to be on utilitarian themes, leaving issues related to justice and equity comparatively under-reported.

Idiopathic right atrial aneurysm

We are describing a rare report of right atrial (RA) aneurysm without any structural heart disease. We are also describing the MRI features of this anomaly. This is first kind of case report in world literature where only isolated RA aneurysm was found without any other structural heart disease.

Presence of ROB-1 beta-lactamase correlates with cefaclor resistance among recent isolates of Haemophilus influenzae

beta-Lactamase production in Canadian isolates of Haemophilus influenzae has remained relatively constant (25-35%) over the last decade despite increasing cefaclor resistance (MIC >/= 32 mg/L). TEM (294/324, 90.7%) and ROB-1 (30/324, 9.3%) prevalence rates among 324 isolates of H. influenzae obtained from across Canada in 1997-1998 were similar (P > 0.05) to previously published reports. However, 66. 7% (26/39) of cefaclor-resistant isolates were ROB-1-positive (P < 0. 001) and the remaining four ROB-1-positive isolates were cefaclor-intermediate (MIC 16 mg/L). Susceptibilities to loracarbef (P < 0.001) and cefprozil were also reduced in the presence of ROB-1 while the activities of cefuroxime, cefotaxime, cefixime and imipenem were similar in both TEM- and ROB-1-positive solates.

Disseminated and atypical molluscum contagiosum in an AIDS patient

A case of disseminated molluscum contagiosum (MC) has been reported in a patient suffering from AIDS. Most of the lesions were erythematous papules and nodules with central unbilication. A few giant lesions and lesions over genitalia were also observed.

Non-cardiac pulmonary oedema in scorpion bite

A 30 year old male presented with non-cardiac pulmonary oedema after scorpion bite. Clinical features, X-ray chest and ECG findings after bite and recovery are discussed.

Static perimetry in the study of amblyopic scotomata

A visual field study of 50 cases of unilateral functional amblyopia revealed a relative central scotoma of 2-10 degrees width and 0.1 to 0.8 LU (log units of neutral density filters) depth in 29 out of 50 cases by static perimetry, while kinetic perimetry revealed a central scotoma in only 3 cases of paramacular fixation. In the majority of cases the eccentric area of fixation lay on the edge of the amblyopic scotoma, and it was identical to the point of peak retinal sensitivity.

Biochemical evaluation of succinic acid therapy in urolithiasis

Reports of Melon et al. [7] and Hodgkinson [4] regarding the efficacy of succinic acid or its derivative (salt) in reducing the endogenous synthesis of oxalate are conflicting. The possible application of succinic acid as a potential inhibitor of oxalate synthesis, and the biochemical alterations resulting therein, has been studied in 10 idiopathic stone-forming patients (6 primary stone-formers and 4 recurrent stone-formers) and in 21 normal adult rats. In rats no significant changes in oxalate excretion were observed during the 4 weeks of succinic acid administration (500 mg/100 g BW/day) and 2 weeks therafter. In the clinical trial of 3 months, where stone-formers were given 20 g/day of succinic acid, the post-therapy values of urinary oxalate excretion showed a singificant drop ( less than 0.001) as compared with those of pretherapy--recurrent stone-formers showing a more marked decrease (63%) than primary stone-formers (49%).