The Wellcome Trust population initiative

This paper describes what the Wellcome Trust has done and aims to do through its population initiative. The Trust is required to spend its funds to improve the physical welfare of mankind, and in this context there can be no more important issue than the rapid changes that are occurring in the human population. The Trust's first involvement was to help fund the New Delhi population summit covered by the world's scientific academics in 1993 and, following discussions with authorities in the field, initiated its funding programme in 1995. Through this programme, the Trust hopes to bring about improved understanding of the relationship between reproductive health, population growth, and sustainable development and create cadres of high quality research scientists in relevant disciplines. Uniquely, funding is available under this programme to suitably qualified applicants from any country other than the USA.      

Dopaminergic behaviour in chicken retina and the effect of form deprivation

Purpose: Dopamine (DA)is cinsidered to be a neurotransmitter involved in light-adaptive responses in the retina and has been implicated in the control of the eye growth include by form deprivation vitreal DOPAC was shown to be a good indicator of retinal dopaminergic activity. Methods/Results: Dopaminergic activity was highest during the light, with vitreal DOPAC levels rising within in 3 hof light exposure. Form deperivation attenuated dopaminergic activity, as the rise in vitreal DOPAC levels on light exposure was rediced in form-depeived eyes, compared with control eyes. Conclusion: The lack sustained activation of DA release may explain the role of DA in the control of eye-growth.     

Interictal 99mTc-HMPAO SPECT in temporal lobe epilepsy: relation to clinical variables

PURPOSE: Factors affecting blood flow observed by interictal single-photon emission computed tomography (SPECT) images in temporal lobe epilepsy (TLE) have not been systematically studied or consistently demonstrated. We evaluated interictal SPECT results with respect to many clinical variables in a large population of TLE patients, all of whom underwent temporal lobectomy. METHODS: Interictal 99mTc-HMPAO SPECT scans from 61 TLE patients were obtained before an anterior temporal lobectomy. SPECT was analyzed using a region of interest analysis (ROI) in the cerebellum, anterior temporal lobe, lateral temporal lobe, mesial temporal lobe, whole temporal lobe, and inferior frontal lobe. Asymmetry indices (AIs) were calculated. Correlative analysis of AIs and clinical variables was performed. RESULTS: The AIs from TLE patients differed significantly from those of controls in the anterior temporal (p < 0.01), lateral temporal (p < 0.001), and whole temporal (p < 0.01) regions. No consistent overall correlation between the AIs and clinical variables existed. In right TLE (RTLE) only, AIs in the lateral and whole temporal lobe were positively correlated with age of onset (r = 0.470, p < 0.05; r = 0.548, p < 0.01, respectively). Similarly, in RTLE only, duration of epilepsy was negatively correlated with the anterior (r = -0.395, p < 0.05) and mesial (r = -0.45, p < 0.05) temporal lobe AI. No correlations were found between clinical variables and AIs in left TLE (LTLE) patients. CONCLUSIONS: Significant correlation of age at onset and duration of epilepsy with AIs in RTLE but not LTLE suggests physiologic processes may be determined in part by laterality of TLE. Clinical applications are problematic.     

Static balance improvement in elderly after dorsiflexors electrostimulation training

The purpose of the present study was to determine the effect of dorsiflexors ElectroStimulation (ES) training, on postural tasks of increasing difficulty in the elderly. Twenty-one elderly adults were randomly assigned into one of two groups: a Training (TG) and a Control Group (CG). The TG (n=10) performed (4 weeks, 4 s/week, 40 min/session) superimposed (electrically evoked and voluntary activation) isometric dorsiflexions (ankle 100°) while seated. Biphasic, rectangular symmetrical pulses (300 ms, 70 Hz, 20–60 mA) were used to provoke maximal muscle activation. Participants performed three static balance tasks (Normal Quiet Stance, Sharpened Romberg, and One-Legged Stance) during which postural sway was quantified using maximum range and standard deviation of Centre of Pressure displacement (Kistler 9281C, 1,000 Hz). Bipolar surface electrodes were used to record the Electromyographic activity (EMG) of Tibialis Anterior, Medial Gastrocnemius, Rectus Femoris and Semi-Tendineous. Two-dimensional kinematic data were collected (60 Hz) and analyzed using the APAS Motion Analysis software. The body was modeled as a five-segment rigid link system. Isometric dorsiflexion moment/angular position relationship was also established using a Cybex dynamometer. ES training resulted in decreased postural sway (P<0.05), greater ankle muscles EMG activity (P<0.001), greater stability of the ankle joint (P<0.05) and significant changes in mean position of all three joints of the lower limb. In addition, dorsiflexion moment significantly (P<0.001) increased as a result of ES training. It is concluded that dorsiflexors ES training, could reduce postural sway and the use of ankle muscles, more characteristic of young adults, might appear in the elderly as well.     

Immunohistochemical evaluation of TGF-β and extracellular matrix proteins expression in rat squamous cell carcinomas

OBJECTIVE: The aim of this study was to establish a possible association between the degree of differentiation of squamous cell carcinomas (SCC) derived from rat oral tissues treated in vivo with the carcinogen 4NQO, and the expression of TGF-β on epithelial cells and the distribution of extracellular matrix proteins (laminin-collagen type IV).
MATERIALS AND METHODS: A parent tumour showing a spectrum of differentiation was used to establish clonal subpopulations that formed differentiated SCC and undifferentiated (spindle cell phenotype) tumours following transplantation to athymic mice.
RESULTS tmmunohistological findings revealed the absence of TGF-β staining on epithelial cells and extracellular matrix proteins in spindle cell tumours. In contrast, staining of SCC revealed a significant number of TGF-β positive cells and the presence of extracellular matrix proteins.
CONCLUSIONS: The findings suggested that there is a positive correlation between histological differentiation, TGF-β expression and the elaboration of extracellular matrix proteins.     

Distribution of T cells and signs of T-cell activation in the rheumatoid joint: implications for semiquantitative comparative histology

A prerequisite for comparative histology of synovial tissue by means of biopsies is insight into the distribution of a marker under study. This investigation focuses on the variation in the presence of T cells and signs of T-cell activation within the rheumatoid joint. For this purpose, multiple slides from several pieces of synovial tissue from different parts of a joint were stained and scored for the expression of CD3, CD25, HLA-DR, Ki67 and interferon-gamma. The variation in scores for the presence of T cells and markers of activation was more pronounced in slides prepared from different pieces of tissue than in slides from one piece of tissue. Based on multiple analysis of variance, methods are suggested to establish a reliable overall score for the expression of a certain marker within a joint. Following validation, such methods may prove to be useful by allowing semiquantitative histology of synovial tissue for studies on arthritis.