alpha A-crystallin (alpha A) and alpha B-crystallin (alpha B) are among the predominant proteins of the vertebrate eye lens. In vitro, the alpha-crystallins, which are isolated together as a high molecular mass aggregate, exhibit a number of properties, the most interesting of which is their ability to function as molecular chaperones for other proteins. Here we begin to examine the in vivo functions of alpha-crystallin by generating mice with a targeted disruption of the alpha A gene. Mice that are homozygous for the disrupted allele produce no detectable alpha A in their lenses, based on protein gel electrophoresis and immunoblot analysis. Initially, the alpha A-deficient lenses appear structurally normal, but they are smaller than the lenses of wild-type littermates. alpha A-/- lenses develop an opacification that starts in the nucleus and progresses to a general opacification with age. Light and transmission electron microscopy reveal the presence of dense inclusion bodies in the central lens fiber cells. The inclusions react strongly with antibodies to alpha B but not significantly with antibodies to beta- or gamma-crystallins. In addition, immunoblot analyses demonstrate that a significant portion of the alpha B in alpha A-/- lenses shifts into the insoluble fraction. These studies suggest that alpha A is essential for maintaining lens transparency, possibly by ensuring that alpha B or proteins closely associated with this small heat shock protein remain soluble.

Myostatin, a member of the TGF-beta family, negatively regulates skeletal muscle development. Depression of myostatin activity leads to increased muscle growth and carcass lean yield. In an attempt to down-regulate myostatin, transgenic mice were produced with a ribozyme-based construct or a myostatin pro domain construct. Though the expression of the ribozyme was detected, muscle development was not altered by the ribozyme transgene. However, a dramatic muscling phenotype was observed in transgenic mice carrying the myostatin pro domain gene. Expression of the pro domain transgene at 5% of beta-actin mRNA levels resulted in a 17-30% increase in body weight (P < 0.001). The carcass weight of the transgenic mice showed a 22-44% increase compared with nontransgenic littermates at 9 weeks of age (16.05 +/- 0.67 vs. 11.16 +/- 0.28 g in males; 9.99 +/- 0.38 vs. 8.19 +/- 0.19 g in females, P < 0.001). Extreme muscling was present throughout the whole carcass of transgenic mice as hind and fore limbs and trunk weights, all increased significantly (P < 0.001). Epididymal fat pad weight, an indicator of body fat, was significantly decreased in pro domain transgenic mice (P < 0.001). Analysis of muscle morphology indicated that cross-sectional areas of fast-glycolytic fibers (gastrocnemius) and fast-oxidative glycolytic fibers (tibialis) were larger in pro domain transgenic mice than in their controls (P < 0.01), whereas fiber number (gastrocnemius) was not different (P > 0.05). Thus, the muscular phenotype is attributable to myofiber hypertrophy rather than hyperplasia. The results of this study suggest that the over-expression of myostatin pro domain may provide an alternative to myostatin knockouts as a means of increasing muscle mass in other mammals.

Subjective and physiological manifestations of the narcotic withdrawal syndrome were produced as a conditioned response. Withdrawal reactions precipitated by the narcotic antagonist naloxone in methadone-dependent volunteers were the unconditioned response. These data support clinical anecdotes of withdrawal symptoms occurring in former addicts when they return to their drug-related environment.

Heavy metal pollution of sediments is a growing concern in most parts of the world, and numerous studies focussed on identifying contaminated sediments by using a range of digestion methods and pollution indices to estimate sediment contamination have been described in the literature. The current work provides a critical review of the more commonly used sediment digestion methods and identifies that weak acid digestion is more likely to provide guidance on elements that are likely to be bioavailable than other traditional methods of digestion. This work also reviews common pollution indices and identifies the Nemerow Pollution Index as the most appropriate method for establishing overall sediment quality. Consequently, a modified Pollution Index that can lead to a more reliable understanding of whole sediment quality is proposed. This modified pollution index is then tested against a number of existing studies and demonstrated to give a reliable and rapid estimate of sediment contamination and quality.

Sarcopenia is the loss of muscle size and function during ageing. The aim of this study was to test whether serum concentrations of myostatin and interacting proteins (GASP-1, FLRG, and follistatin) differed between young and elderly sarcopenic men. Isometric knee extensor maximal voluntary contraction and quadriceps cross-sectional area (magnetic resonance imaging measurement) were significantly higher in young (22 ± 2 years; 266 ± 54 N/m; 8,686 ± 1,154 mm(2)) than in mildly sarcopenic (69 ± 3 years; 183 ± 17 N/m; 6,621±718 mm(2)) and severely sarcopenic men (76 ± 6 years; 127 ± 23 N/m; 5,846 ± 591 mm(2)), respectively (p ≤ .01 for all comparisons). There was a trend (p = .06) toward higher FLRG in young (20 ± 8 ng/mL) than in mildly (15 ± 6 ng/mL) and severely sarcopenic men (17 ± 8 ng/mL). Myostatin, follistatin, GASP-1, tumor necrosis factor α, and interleukin-6 did not differ significantly. Insulin-like growth factor-1 and free testosterone were both significantly lower in sarcopenic men (p < .001). This suggests that altered serum concentrations of myostatin and myostatin-interacting proteins are not contributing to sarcopenia with the possible exception of FLRG.

alphaB-crystallin is a member of the small heat shock protein family and can act as a molecular chaperone preventing the in vitro aggregation of other proteins denatured by heat or other stress conditions. Expression of alphaB-crystallin increases in cells exposed to stress and enhanced in tumors of neuroectodermal origin and in many neurodegenerative diseases. In the present study, we examined the properties of lens epithelial cells derived from mice in which the alphaB-crystallin gene had been knocked out. Primary rodent cells immortalize spontaneously in tissue culture with a frequency of 10(-5) to 10(-6). Primary lens epithelial cells derived from alphaB-crystallin-/- mice produced hyperproliferative clones at a frequency of 7.6 x 10(-2), four orders of magnitude greater than predicted by spontaneous immortalization (1). Hyperproliferative alphaB-crystallin-/- cells were shown to be truly immortal since they have been passaged for more than 100 population doublings without any diminution in growth potential. In striking contrast to the wild-type cells, which were diploid, the alphaB-crystallin-/- cultures had a high proportion of tetraploid and higher ploidy cells, indicating that the loss of alphaB-crystallin is associated with an increase in genomic instability. Further evidence of genomic instability of alphaB-crystallin-/- cells was observed when primary cultures were infected with Ad12-SV40 hybrid virus. In striking contrast to wild-type cells, alphaB-crystallin-/- cells expressing SV40 T antigen exhibited a widespread cytocidal response 2 to 3 days after attaining confluence, indicating that SV40 T antigen enhanced the intrinsic genomic instability of alphaB-crystallin-/- lens epithelial cells. These observations suggest that the widely distributed molecular chaperone alphaB-crystallin may play an important nuclear role in maintaining genomic integrity.

Objective: To describe cardiovascular disease (CVD) risk management in Indigenous primary health care. Design, setting and participants: Review of 1165 randomly selected case records of Indigenous Australian adults, aged ≥ 18 years, regularly attending eight health services in diverse settings in New South Wales, Queensland and Central Australia, October 2007 – May 2008. Main outcome measure: Adherence to CVD risk screening and management guidelines, especially with respect to overall or absolute CVD risk. Results: More than half the people in the sample (53%) were not adequately screened for CVD risk according to national recommendations. Underscreening was significantly associated with younger age, less frequent attendance, and lower uptake of the Medicare Health Assessment. Of the sample, 9% had established CVD, and 29% of those aged ≥ 30 years were classified as high risk according to the 2004 National Heart Foundation of Australia (NHFA) adjusted Framingham equation. Of those with CVD, 40% (95% CI, 30%–50%) were not prescribed a combination of blood pressure (BP) medicines, statins and antiplatelet agents, and 56% (95% CI, 49%–62%) of high‐risk individuals without CVD were not prescribed BP medicines and statins. For high‐risk individuals not prescribed BP medicines or statins, 74% (95% CI, 64%–84%) and 30% (95% CI, 23%–39%) respectively, did not meet 2004 NHFA criteria for prescribing of these medications, and of those already prescribed BP medicines or statins, 41% (95% CI, 36%–47%) and 59% (95% CI, 52%–66%) did not meet respective guideline targets. Conclusions: These management gaps are similar to those found in non‐Indigenous health care settings, suggesting deficiencies across the health system. Prescribing guidelines which exclude many high‐risk individuals contribute to suboptimal management. Guideline reform and improved health service capacity could substantially improve Indigenous vascular health.

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