The cerebrovascular effects of PRP-1

More than 50 years ago we demonstrated that the neurosecretory NSO and NPV cells of the hypothalamus can produce not only releasing hormones, such as vasopressin and oxytocin, but also hormones that are able to regulate cardiac activity and coronary circulation. Moreover, we showed that 5?C6 min after intravenous administration (1 mg/kg) to a cat of a coronarydilatory protein of the hypothalamus that we isolated the blood pressure in the vertebral artery gradually decreased, reaching 20?C30 ml of Hg following two or more administrations, thus indicating the reduction of cerebral vessel tonus. These results indicate that the protein we isolated is able to dilate the blood vessels of both the heart and the brain. Later, we isolated these proteins from animal neurohypophysis, which indicates the hormonal nature of these proteins and polypeptides. Moreover, the proline-rich polypeptides PRP-1 (Galarmin) that we isolated and chemically characterized as consisting of 15 amino-acid residues, has coronarydilatory properties. It was of great interest to investigate the activity of Galarmin on normal and damaged cerebral blood flow. Our experimental results demonstrated the ability of PRP-1 to repair damaged cerebral blood flow caused by common carotid artery occlusion.     

Visual capabilities and cortical maps in BALB/c mice

By combining behavioural analyses with intrinsic signal optical imaging, we analysed visual performance and visual cortical activity in the albino mouse strain BALB/c, which is increasingly being used as an animal model of neuropsychological disorders. Visual acuity, as measured by a virtual‐reality optomotor system, was 0.12 cycles per degree (cyc/deg) in BALB/c mice and 0.39 cyc/deg in pigmented C57BL/6 mice. Surprisingly, BALB/c mice showed reflexive head movements against the direction of the rotating stimulus. Contrast sensitivity was significantly lower in BALB/c mice (45% contrast at 0.064 cyc/deg) than in C57BL/6 mice (6% contrast). In the visual water task, visual acuity was 0.3 cyc/deg in BALB/c mice and 0.59 cyc/deg in C57BL/6 mice. Thus, the visual performance of BALB/c mice was significantly impaired in both behavioural tests – visual acuity was ～ 0.3 cyc/deg lower than in C57BL/6 mice, and contrast sensitivity was reduced by a factor of ～ 8. In BALB/c mice, visual cortical maps induced by stimulation of the contralateral eye were normal in both activation strength and retinotopic map quality. In contrast, maps induced by ipsilateral eye stimulation differed significantly between the strains – activity in a region representing 15° to 19° elevation in the visual field was significantly weaker in BALB/c mice than in C57BL/6 mice. Taken together, our observations show that BALB/c mice, like the albino animals of other species, have a significantly lower visual performance than C57BL/6 mice and a modified cortical representation of the ipsilateral eye that may impair stereopsis. Thus, our results caution against disregarding vision as a confounding factor in behavioural tests of neuropsychological disorders.     

Anhedonic-like traits and lack of affective deficits in 18-month-old C57BL/6 mice: Implications for modeling elderly depression

The prevalence of depression increases with aging. We hypothesized that like humans, old animals exhibit anhedonic-like behavior, along with signs of behavioral despair. In rodents, anhedonia, a reduced sensitivity to reward, which is listed as a core feature of major depression in the DSM-IVR, can be measured by a decrease in intake of and preference for sweet solutions. Here, sucrose intake, forced swimming, immobility in the modified tail suspension test, novelty exploration, grooming, anxiety and locomotor activity were compared in naïve 3- and 18-month-old male C57BL/6 mice. The absolute amounts and the ratio of consumed 1% sucrose solution to water intake was significantly smaller in 18-month-old mice than in 3-month-old mice. The consumption of 5%-sucrose solution requiring high levels of drinking effort, novelty exploration in two setups and grooming behavior in the splash test were reduced in older animals. Analysis of other behaviors suggested that the above-mentioned signs of anhedonic-like traits were unlikely to be attributable to the potential effect of aging on metabolic needs for water, taste perception, motor capabilities or the induction of essential anxiety and neophobia. A 4-week treatment with the antidepressant imipramine (7 mg/kg/day) or dimebon, a compound with suggested neuroprotective proneurogenic properties (1 mg/kg/day) restored sucrose intake and preference in 18-month-old mice. Meanwhile, young and old mice showed no differences in the parameters of behavioral despair evaluated in the forced swim and modified tail suspension tests. Thus, the behavioral profile of aged mice parallels that of humans with elderly depression, in whom the symptoms of hedonic deficits typically outweigh affective disturbances. The assessment of anhedonic-like traits with the sucrose preference test in 18-month-old mice will be useful in preclinical studies of elderly depression.     

Sociodemographic factors associated with cervical cancer screening and follow-up of abnormal results

Objective

To determine the sociodemographic factors associated with cervical cancer screening and follow-up of abnormal results.

Design

Population cohort study.

Setting

Ontario.

Participants

Women between the ages of 18 and 70 years who were eligible for Papanicolaou testing.

Main outcome measures

Rates of cervical cancer screening and follow-up of abnormal and inadequate Pap test results, and associated sociodemographic factors such as age, neighbourhood income level, and health region. Multivariate logistic regression was used to identify independent factors associated with screening and follow-up.

Results

Of the 3.7 million women eligible for screening, 69% had had Pap tests in the past 3 years. These rates varied by age, income, and region (P < .001). Women residing in the lowest-income neighbourhoods were half as likely to be screened (odds ratio 0.56, 95% CI 0.55 to 0.56). Only 44% of those whose Pap test results revealed atypical squamous cells of uncertain significance or low-grade squamous intraepithelial lesions had repeat Pap tests or colposcopy within 6 months, and this varied by age, income, and region (P < .001). Among women with unsatisfactory Pap test results, only 35% were retested within 4 months, and this varied by age (P < .001).

Conclusion

Despite universal health coverage, cervical cancer screening rates are suboptimal among low-income women at greatest risk. Follow-up among women with inadequate or abnormal test results is often poor. Novel models of cervical cancer screening are needed to address these inadequacies.     

Automated Bone Tumor Segmentation and Classification as Benign or Malignant Using Computed Tomographic Imaging

Journal of Digital Imaging - The purpose of this study was to pair computed tomography (CT) imaging and machine learning for automated bone tumor segmentation and classification to aid clinicians...