A comparison of rat SPECT images obtained using (99m)Tc derived from 99Mo produced by an electron accelerator with that from a reactor

Recent shortages of molybdenum-99 ((99)Mo) have led to an examination of alternate production methods that could contribute to a more robust supply. An electron accelerator and the photoneutron reaction were used to produce (99)Mo from which technetium-99m ((99m)Tc) is extracted. SPECT images of rat anatomy obtained using the accelerator-produced (99m)Tc with those obtained using (99m)Tc from a commercial generator were compared. Disks of (100)Mo were irradiated with x-rays produced by a 35 MeV electron beam to generate about 1110 MBq (30 mCi) of (99)Mo per disk. After target dissolution, a NorthStar ARSII unit was used to separate the (99m)Tc, which was subsequently used to tag pharmaceuticals suitable for cardiac and bone imaging. SPECT images were acquired for three rats and compared to images for the same three rats obtained using (99m)Tc from a standard reactor (99)Mo generator. The efficiency of (99)Mo-(99m)Tc separation was typically greater than 90%. This study demonstrated the delivery of (99m)Tc from the end of beam to the end user of approximately 30 h. Images obtained using the heart and bone scanning agents using reactor and linac-produced (99m)Tc were comparable. High-power electron accelerators are an attractive option for producing (99)Mo on a national scale.

Self-presentation origins of choking: evidence from separate pressure manipulations

Whether self-presentation is involved in the choking process remains unknown. The purpose of the current study was to determine the role of self-presentation concerns on the frequency of choking within the context of a recently proposed self-presentation model. Experienced field hockey players (N = 45) were randomly assigned to one of five groups (i.e., performance-contingent monetary incentive, video camera placebo, video camera self-presentation, audience, or combined pressure), before taking penalty strokes in low- and high-pressure phases. Results indicated that groups exposed to self-presentation manipulations experienced choking, whereas those receiving motivational pressure treatments decreased anxiety and increased performance under pressure. Furthermore, cognitive state anxiety mediated the relationship between the self-presentation group and performance. These findings provide quantitative support for the proposed self-presentation model of choking, while also holding implications for anxiety manipulations in future sport psychology research.

Does sports club participation contribute to health-related quality of life?

Given the social nature of participation in sport, we hypothesized that club sports participants would have greater well-being and quality of life than participants in other forms of physical activity (PA).

PURPOSE

The purpose of this study was to examine health-related quality of life and life satisfaction in women who participate in three contrasting forms of PA: club sport, gym activities, and walking.

METHODS

This was a cross-sectional study of the relationship between type of PA setting and measures of health-related quality of life (Short-Form Health Survey [SF-36]) and life satisfaction in 818 women living in rural Victoria, Australia, in 2007. Data were also compared with those from a normative sample of 2345 women.

RESULTS

After adjustment for potential confounders (age, education, marital status, children aged <16 yr, perceived financial stress, and level of recreational PA), four of the eight SF-36 subscales, the SF-36 mental health component summary score, and life satisfaction were significantly higher in the club sport group than that in the other groups.

CONCLUSION

Although cross-sectional research cannot establish causal links, the results suggest that participation in club sport may enhance the health benefits of PA.

Transition in participation in sport and unstructured physical activity for rural living adolescent girls

Physical activity (PA) is important for lifelong health; however, participation is lower in rural compared with metropolitan areas and declines during adolescence, particularly for girls. It is likely that this decline is related to the number of life transitions that occur during adolescence. This qualitative study examined the views of active rural living girls regarding the factors affecting their sport and PA participation, using the socioecological model. Twenty-seven girls aged 16-17 from four schools participated in semi-structured focus group discussions. Content and thematic analysis was conducted from verbatim transcripts using NVivo. The girls enjoyed involvement in community club sport with friends and they reported living in communities where participation in sport was a major form of social interaction. However, the desire to succeed educationally was a critical factor affecting their participation in sport and PA and influenced their movement from structured club sport to more flexible, but socially isolated individual activities. It is recommended that future longitudinal research should track rural living adolescent females as they complete secondary school, in order to better understand the influence of educational priorities upon sport and PA participation and to identify practical strategies for both schools and community organizations to foster continuing participation throughout this crucial period of life transition.

Using a socioecological approach to examine participation in sport and physical activity among rural adolescent girls

Adolescence is a critical time for developing lifelong healthy behaviors, including active lifestyles. Participation in sport and physical activity, however, declines during adolescence, and few studies have comprehensively identified why, particularly among rural girls. This article identifies a range of independent and interacting factors that influence sport and physical activity participation of rural adolescent girls. The socioecological model of health was used to guide four focus group discussions with Grade 7 girls (n = 34). The results showed that adolescent girls were positively influenced when sports or physical activities were fun, when they involved being with friends, and when they were supported by families and teachers through role modeling and positive feedback. A range of intrapersonal and organizational factors affected perceived self-competence, particularly the coeducational nature of school physical education classes and peer teasing, which supported social comparisons of skill level. In promoting sport and physical activity to rural adolescent girls, focus must be directed on developmentally appropriate activities that are fun, offering opportunities for single-sex classes, and generating cultural changes that encourage noncompetitive and self-referencing activities.

Effect of a nurse back injury prevention intervention on the rate of injury compensation claims

PROBLEM

This study evaluated the effect of introducing a No Lifting policy on back injuries to nurses, across an entire health care system.

METHODS

Methods included: analysis of the data for all public health agencies in the Australian state of Victoria; compensation data from the Victorian Workcover Authority; data about workforce and program implementation from a retrospective survey of agencies; longitudinal analysis of standardized workers compensation claim rates for back injuries before, during and after the intervention.

RESULTS

A statistically significant decline in back injury claim rates during implementation contrasted with no statistically significant trends within the periods before and after the intervention. A statistically significant reduction occurred in mean quarterly standard back injury claim incidence rates per 1,000 equivalent fulltime nursing staff (EFTNS), representing a 24% reduction in standard back injury claims/1000 EFTNS.

DISCUSSION

Ergonomics principles encourage changing the work environment to suit the worker. This approach delivered a significant improvement in the immediate term.

IMPACT OF INDUSTRY

The substantial decline in back injury rates signifies a major improvement in the safety of a critical aspect of the work environment for nurses.

Effect of a low-resource-intensive lifestyle modification program incorporating gymnasium-based and home-based resistance training on type 2 diabetes risk in Australian adults

OBJECTIVE

The purpose of this study was to assess the effectiveness of a low-resource-intensive lifestyle modification program incorporating resistance training and to compare a gymnasium-based with a home-based resistance training program on diabetes diagnosis status and risk.

RESEARCH DESIGN AND METHODS

A quasi-experimental two-group study was undertaken with 122 participants with diabetes risk factors; 36.9% had impaired glucose tolerance (IGT) or impaired fasting glucose (IFG) at baseline. The intervention included a 6-week group self-management education program, a gymnasium-based or home-based 12-week resistance training program, and a 34-week maintenance program. Fasting plasma glucose (FPG) and 2-h plasma glucose, blood lipids, blood pressure, body composition, physical activity, and diet were assessed at baseline and week 52.

RESULTS

Mean 2-h plasma glucose and FPG fell by 0.34 mmol/l (95% CI -0.60 to -0.08) and 0.15 mmol/l (-0.23 to -0.07), respectively. The proportion of participants with IFG or IGT decreased from 36.9 to 23.0% (P = 0.006). Mean weight loss was 4.07 kg (-4.99 to -3.15). The only significant difference between resistance training groups was a greater reduction in systolic blood pressure for the gymnasium-based group (P = 0.008).

CONCLUSIONS

This intervention significantly improved diabetes diagnostic status and reduced diabetes risk to a degree comparable to that of other low-resource-intensive lifestyle modification programs and more intensive interventions applied to individuals with IGT. The effects of home-based and gymnasium-based resistance training did not differ significantly.

The effects of interval–exercise duration and intensity on oxygen consumption during treadmill running

The magnitude of improvement in peak oxygen uptake (V(o)(2peak))) and performance to an exercise training regime is related to the V(o)(2) of prior accumulated exercise training bouts. However, it is unclear whether constant rate training (CRT) or interval training (INT) preferentially alters the V(o)(2) of running exercise. Therefore, the purpose of this study was to compare the acute V(o)(2) response to constant, and interval training sessions. Consequently, this study compared the mean average V(o)(2) of 17 moderately trained participants to a 20-min CRT and two different 20min INT treadmill runs. Participants completed three treatments (twice) in random order over 3 weeks. In 1min INT participants completed 10x1min efforts at the velocity corresponding to V(o)(2peak) (V(peak)) interspersed with 10x1min efforts at 0.5V(peak). In the 2min INT, participants completed 5x2min efforts at the V(peak) interspersed with 5x2min efforts at 0.5 at V(peak). In CRT participants ran at a velocity equivalent to the mean velocity of INT (75% V(peak)). Mean average V(o)(2) for 2min INT, 1min INT and CRT were, respectively, 3200+/-661; 3076+/-6041; 2909+/-584mlmin(-1). Both INT sessions resulted in a significantly higher mean average V(o)(2) than CRT. Furthermore, 2min INT resulted in 90% of V(o)(2peak) being exceeded more frequently than 1min INT. We conclude that INT serves as a more potent stimulus for improvement in V(o)(2peak) and subsequent endurance performance than CRT.

Making sporting clubs healthy and welcoming environments: a strategy to increase participation

Sporting clubs are an ideal setting to promote community-wide participation in physical activity. Using the principles of the Ottawa Charter as a guide, this study explored the factors affecting the development of supportive environments as a mechanism to increase participation in club sport. The Victorian Health Promotion Foundation (VicHealth) funds State Sporting Associations (SSAs) to develop healthy and welcoming environments (HWE) in their associated clubs. The program focus areas are: welcoming and inclusive environments, sports injury prevention, 'smoke-free' environments, responsible serving of alcohol, sun protection and healthy eating. This paper sought to determine whether or not SSA Executive Officers (EOs) believe that the creation of a supportive environment will facilitate sporting club membership and to identify the factors that affect the development of the HWEs. Forty-two (82.4%) of the 51 funded SSAs completed a general survey and 36 (70.6%) of EOs responded to questions that were specifically addressed to them. EOs from six SSAs also participated in semi-structured interviews. SSA EOs (97.2%) believed that the creation of HWE in clubs would facilitate increases in participant membership. However, the data indicate incomplete development of the HWE focus areas at the club level because of limited club capacity and limited SSA support. Reportedly, the SSAs are at the stage of raising program awareness at the club level. It is suggested that SSAs should plan a structured approach to the development of HWEs that acknowledges the diverse capacity of their clubs, and garner the support of key club volunteers in order to establish HWEs.

Development of body oxygen stores in harbor seals: effects of age, mass, and body composition

Harbor seal pups are highly precocial and can swim and dive at birth. Such behavioral maturity suggests that they may be born with mature body oxygen stores or that stores develop quickly during the nursing period. To test this hypothesis, we compared the blood and muscle oxygen stores of harbor seal pups, yearlings, and adults. We found that pups had smaller oxygen stores than adults (neonates 57%, weaned pups 75%, and yearlings 90% those of adults), largely because neonatal myoglobin concentrations were low (1.6+/-0.2 g% vs. 3.8+/-0.3 g% for adults) and changed little during the nursing period. In contrast, blood oxygen stores were relatively mature, with nursing pups having hematocrit (55%+/-0.2%), hemoglobin (21.7+/-0.4 g%), and blood volume (12.3+/-0.5 mL/kg) only slightly lower than the corresponding values for adults (57%+/-0.2%, 23.8+/-0.3 g %, and 15.0+/-0.5 mL/kg). Because neonatal pups had relatively high metabolic rates (11.0 mL O2/kg min), their calculated aerobic dive limit was less than 50% that of adults. These results suggest that harbor seals' early aquatic activity is primarily supported by rapid development of blood, with immature muscle oxygen stores and elevated use rates limiting aerobic diving ability.

Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California

An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia.

An analysis of the forces required to drag sheep over various surfaces

Some occupational health and safety hazards associated with sheep shearing are related to shearing shed design. One aspect is the floor of the catching pen, from which sheep are caught and dragged to the shearing workstation. Floors can be constructed from various materials, and may be level or gently sloping. An experiment was conducted using eight experienced shearers as participants to measure the force exerted by a shearer when dragging a sheep. Results showed that significant changes in mean dragging force occurred with changes in both surface texture and slope. The mean dragging forces for different floor textures and slopes ranged from 359 N (36.6 kg) to 423N (43.2 kg), and were close to the maximum acceptable limits for pulling forces for the most capable of males. The best floor tested was a floor sloped at 1:10 constructed of timber battens oriented parallel to the path of the drag, which resulted in a mean dragging force 63.6N (15%) lower than the worst combination.

Immunohistochemical evidence for estrogen receptors in meibomian glands

PURPOSE

To look for sex hormone receptor distribution in three structures contributing to the normal human tear film: the conjunctiva, the accessory lacrimal glands, and the meibomian glands.

DESIGN

An immunohistochemical study. TISSUES AND CONTROLS: Forty-one upper eyelid specimens were collected from 15 male and 26 female patients (age range, 1.5-85 years) during blepharoptosis surgery via posterior tarsoconjunctival mullerectomy (Fasanella-Servat or Gavaris). In addition, control sections of histologically normal breast, prostate, and skin tissue were obtained.

METHODS

Immunohistochemical staining using mouse monoclonal antibodies against estrogen, progesterone, and androgen receptors was performed on all tissues and controls. Quantitation of the receptors was performed and expressed as percentage nuclear positivity. Specimens were divided into three groups based on the age of the patient: <12 years (n = 9); 18-55 years (n = 1); >55 years (n = 12).

RESULTS

Forty-one specimens contained conjunctiva. All were negative for estrogen, progesterone, and androgen receptors. Twenty-four specimens contained accessory lacrimal glands of Wolfring. All were negative for the three receptors. Twenty-two specimens contained meibomian glands. All were positive for estrogen receptors; one was positive for progesterone receptors and one for androgen receptors. Using Minitab statistical software (Minitab Inc. State College, PA), analysis of variation revealed no statistical difference between sexes or between age groups studied. The sebaceous glands of skin were uniformly positive for androgen receptors. Sebaceous glands of the face and scalp (3 of the 15 skin samples) were also positive for estrogen receptors.

CONCLUSIONS

Estrogen receptors are present in the meibomian glands of the upper eyelid. Unlike sebaceous glands elsewhere on the skin, the meibomian glands lack androgen receptors. Estrogen receptors may play a role in modulation of the lipid layer of the tear film, and their activity may be linked to meibomian gland dysfunction and dry eye syndrome.

Characterization of adrenergic receptors in the accessory lacrimal glands of the upper eyelid

PURPOSE

To identify the histologic location as well as the exact subtype of adrenergic receptors in the accessory lacrimal glands of the upper eyelid.

METHODS

Upper eyelid specimens were collected from 19 patients undergoing routine blepharoptosis correction via a posterior tarsoconjunctival mullerectomy. Immunohistochemical staining using polyclonal antibodies against human alpha 1, alpha 2, beta 1, and beta 2 receptors was performed on all specimens.

RESULTS

beta 1 receptors were the predominant adrenergic receptor subtype in the glands of Wolfring.

CONCLUSIONS

The presence of beta 1 receptors in the accessory lacrimal glands of the upper eyelid may suggest a possible role for selective beta 1 agonists in the treatment of keratitis sicca.

Distribution of adrenergic receptor subtypes in the retractor muscles of the upper eyelid

PURPOSE

To identify adrenergic receptor subtypes and their relative distribution in the retractor muscles of the upper eyelid, the levator palpebrae superioris, and the Müller muscle. The pattern of distribution of these receptors in the Müller muscle was further compared in patients with dysthyroid eyelid retraction and in normal subjects.

METHODS

Müller muscle specimens were collected from 19 patients undergoing ptosis correction and from 8 patients undergoing repair of dysthyroid eyelid retraction. Immunohistochemical staining for alpha 1-, alpha 2-, beta 1-, and beta 2-adrenergic receptors was performed using antihuman rabbit polyclonal antibodies.

RESULTS

alpha 2-Adrenergic receptors were the predominant subtype in the Müller muscle, and beta 1-adrenergic receptors were the predominant subtype in the levator muscle. There was no significant difference in the staining pattern between specimens collected from patients with dysthyroid eyelid retraction and those from normal subjects.

CONCLUSIONS

The interaction between the alpha 2 and beta 1 receptors in the upper eyelid retractor muscles may be important in the control of the upper eyelid position and may contribute to the development of dysthyroid eyelid retraction. Specific alpha 2 antagonists could be developed and may be effective pharmacologic agents for the treatment of eyelid retraction.

Sensitivity and specificity of the diagnosis of periocular lesions by oculoplastic surgeons

BACKGROUND

A few studies have assessed the sensitivity of ophthalmologists in diagnosing periocular lesions. However, no study has assessed their diagnostic specificity or the degree to which they overdiagnose various lesions. We performed a study to determine the sensitivity and specificity of oculoplastic surgeons' preoperative diagnoses of common and uncommon periocular lesions.

METHODS

Using the patient records of four oculoplastic ophthalmologists, we reviewed all charts documenting periocular surgery in which lesions were excised and sent for biopsy. For each of 358 cases we recorded the preoperative diagnosis as listed by the surgeon and the postoperative diagnosis as reported by the pathologist. Each preoperative diagnosis was then scored as correct or incorrect. The relative number of each type of lesion was determined, and the ophthalmologists' sensitivity and specificity were calculated.

RESULTS

The sensitivity and specificity for the eight most frequently lesions were (in order of frequency) basal cell carcinoma 92.1% and 81.6% respectively, papilloma 81.6% and 66.0%, cyst 66.7% and 69.7%, nevus 53.6% and 75.0%, seborrheic keratosis 27.8% and 71.4%, chalazion 93.3% and 100.0%, squamous cell carcinoma 33.3% and 55.6%, and xanthelasma 100.0% and 76.9%. The values for melanoma were 50.0% and 28.6%, for sebaceous gland carcinoma 0.0% and 100.0%, and for uncommon lesions (nonspecific inflammation, actinic keratosis, granuloma, cavernous hemangioma, folliculitis, benign sweat gland tumour, eccrine hidrocystoma and collagenous tissue) 27.8% and 57.1%. The overall accuracy in lesion identification was 70.0%.

INTERPRETATION

Although ophthalmologists have excellent diagnostic sensitivity and specificity for some types of lesion, such as basal cell carcinoma and chalazion, the identification of other lesion types, such as cyst, squamous cell carcinoma and possibly melanoma and sebaceous gland carcinoma, is less optimal.

Sclerosing sweat-duct carcinoma (malignant syringoma) of the upper eyelid: a patient report with immunohistochemical and ultrastructural analysis

Sclerosing sweat-duct carcinoma or malignant syringoma is a rare eyelid tumor. The authors report the first patient with sclerosing sweat-duct carcinoma involving the upper eyelid and present its immunohistochemical and ultrastructural features. The clinical features and the histopathologic and ultrastructural findings that distinguish this tumor from its benign counterparts are discussed. Sclerosing sweat-duct carcinomas are slow growing but locally invasive neoplasms that have a propensity to recur. Wide and deep surgical excision with frozen section evaluation of margins is recommended.

Transcanalicular removal of silastic nasolacrimal tubes

Removal of nasolacrimal tubes is often an awkward procedure when performed transnasally, especially in children and apprehensive adults. We evaluated in a prospective fashion the transcanalicular route to retrieve nasolacrimal tubes. Overall, this technique was well tolerated by patients and easy to perform. Tube breakage during removal may be a complication.

Blastogenesis and interleukin-2 receptor expression assays in the harbor seal (Phoca vitulina)

Two in vitro functional assays were developed to evaluate mitogen-induced responses of peripheral blood mononuclear leukocytes (PBML) from free-ranging harbor seals, Phoca vitulina. Lymphocyte proliferation was measured by a standard blastogenesis assay following optimization of culture conditions including mitogen concentration, cell density, and incubation time. These optimized parameters, with the exception of incubation time, were subsequently employed to measure lymphocyte activation by analytical flow cytometry using fluorochrome-based identification of cell surface interleukin-2 receptor (IL-2r) expression. Baseline values established for free-ranging harbor seals had extensive animal variability; there was evidence that the samples were derived from a group of animals with a normal distribution. Positive correlations were observed between blastogenesis assays, and between blastogenesis and activation assays, when using pokeweed or concanavalin A as the stimulus. However, no relationship was found in the expression of the IL-2r induced by these mitogens. This result supports the contention that the two mitogens stimulate different lymphocyte subpopulations. This was observed only with the IL-2r expression assay because of its unique ability to measure the number of T lymphocytes initially activated rather than the ultimate number of progeny cells identified by blastogenesis. Both assays, used concurrently, should provide a more comprehensive representation of lymphocyte competence and serve as a measure of animal health.