Effect of a lifestyle intervention on change in cardiorespiratory fitness in adults with type 2 diabetes: results from the Look AHEAD Study.

OBJECTIVE: To examine the effect of an intensive lifestyle weight loss intervention (ILI) compared to diabetes support and education (DSE) on changes in fitness and physical activity in the Look AHEAD trial. DESIGN: Randomized clinical trial to compare a lifestyle intervention for weight loss with a DSE condition in individuals with type 2 diabetes. SUBJECTS: Data from 4376 overweight or obese adults with type 2 diabetes (age=58.7+/-6.8 years, body mass index (BMI)=35.8+/-5.8 kg/m(2)) who completed 1 year of the Look AHEAD trial and had available fitness data were analyzed. INTERVENTION: Subjects were randomly assigned to DSE or ILI. DSE received standard care plus three education sessions over the 1-year period. ILI included individual and group contact throughout the year, restriction in energy intake and 175 min per week of prescribed physical activity. MEASUREMENTS: Fitness was assessed using a submaximal graded exercise test. Physical activity was assessed by questionnaire in a subset of 2221 subjects. RESULTS: Change in fitness was statistically greater in ILI vs DSE after adjustment for baseline fitness (20.9 vs 5.7%; P<0.0001). Multivariate analysis showed that change in fitness was greater in overweight vs obese Class II and III (P<0.05). Physical activity increased by 892+/-1694 kcal per week in ILI vs 108+/-1254 kcal per week in DSE (P<0.01). Changes in fitness (r=0.41) and physical activity (r=0.42) were significantly correlated with weight loss (P<0.0001). CONCLUSIONS: The ILI was effective in increasing physical activity and improving cardiorespiratory fitness in overweight and obese individuals with type 2 diabetes. This effect may add to weight loss in improving metabolic control in patients in lifestyle intervention programs.

A review of assigned protection factors of various types and classes of respiratory protective equipment with reference to their measured breathing resistances.

The British Standards Institution 'Guide to implementing an effective respiratory protective device programme' (BS 4275) lists assigned protection factors (APFs) for various types of respiratory protective equipment (RPE). The APFs were allocated either on the basis of available workplace studies data which met set criteria or on the basis of professional judgement that there is equivalence between its operation and that of a device for which an APF is derived from workplace data. However, in many cases no workplace study information exists to support this professional judgement. As an interim measure, pending information based on workplace measurements, the breathing resistance of a range of tight-fitting RPE from negative pressure filtering devices through to self-contained positive pressure breathing apparatus was measured at various breathing rates. The relative inhalation resistances were then compared on the assumption that similar breathing resistance performance is likely to give similar inward leakage on a facepiece and hence similar protection if all other factors, such as fit, etc., are equal. This work indicates that for most devices the allocation of APFs by analogy to other devices seems to be acceptable. However, there appears to be no justification for the allocation of an APF value of 100 to continuous flow compressed air line breathing apparatus. It is recommended that it should be lowered to 40 until there is valid workplace study data to support the current APF of 100. The work provides an informative insight into the relative performance of devices.

Intraorbital anatomy of the koala (Phascolarctos cinereus).

This is the first documented study of the anatomical details of the contents of the normal koala orbit, excluding the bulbus oculi. Baseline data were established which are necessary for understanding and treating ocular disease in the koala (Phascolarctos cinereus). The anatomy of the orbital contents of the koala were examined and described from animals that presented dead or were euthanized for humane reasons. Dissections of the orbital cavity were performed under magnification. Polymethyl methacrylate (PMMA) casts of the nasolacrimal system and the vascular supply of the orbit were also made in order to study these systems. The superficial lymphatic drainage of the conjunctival tissues was studied by subcutaneous injection of Evan's Blue into the palpebral conjunctiva of a freshly deceased animal, and by Microfil casts of the efferent lymphatics. In general, the orbital contents of the koala are consistent with those of other carnivorous polyprotodont and herbivorous diprotodont marsupials.

The cytomorphology of ocular surface squamous neoplasia by using impression cytology.

BACKGROUND: The term ocular surface squamous neoplasia (OSSN) encompasses conjunctival and corneal intraepithelial neoplasia through to invasive squamous cell carcinoma of the ocular surface. The disease is related to prolonged exposure to solar ultraviolet light and has been proposed as an acquired immune deficiency syndrome-associated tumor. To the authors' knowledge, very few reports describing the cytology of these lesions have been published. METHODS: Impression cytology (IC) samples collected from the eyes of patients with a range of ocular surface diseases were available for study. From these, 267 sets of impressions had subsequent histopathology that had been collected within 6 months of the IC, and which indicated the presence of OSSN. The IC from these cases was used to describe the cytomorphology of intraepithelial and invasive OSSN. RESULTS: Within the intraepithelial group, keratinized dysplastic cells that often were accompanied by hyperkeratosis, syncytial-like groupings, and nonkeratinized dysplastic cells were described. Within the invasive group, cases with significant keratinization and an additional group of cases with little keratinization and sometimes also prominent macronucleoli were described. Keratinized cases were the most numerous in both the intraepithelial and invasive groups. A description also was given of a low number of cases with cytology and also subsequent histopathology indicating the presence of intraepithelial OSSN, in the absence of a clinically detectable lesion. CONCLUSIONS: This detailed description of the cytomorphology of a high number of cases of OSSN with confirmation by histopathology should assist others with little experience of the cytology of these lesions to examine them with increased confidence. Cancer (Cancer Cytopathol)

Efficacy of a training programme designed to teach cervical smear screeners to identify ocular surface squamous neoplasia using conjunctival impression cytology.

Ocular surface squamous neoplasia (OSSN) is a recently proposed term introduced to encompass both intraepithelial neoplasia and invasive squamous cell carcinoma of the conjunctiva and cornea. A teaching programme incorporating a manual, slide sets, and an evaluation test was developed. The aim was to teach experienced cervical smear screeners to evaluate ocular surface specimens collected by conjunctival impression cytology, with a minimum of individual tuition. The use of the manual was well accepted and half of the original six candidates were able to master the new skill adequately within 8 h. It was considered that the differences between the cytology of OSSN and the equivalent lesions of the uterine cervix are sufficient to prevent some experienced screeners acquiring these skills rapidly.

Immunology simplified.

An understanding of the inflammatory and immune response is necessary to recognize conditions that alter these responses. Because normal inflammatory and immune responses are necessary for postoperative healing, the nurse needs to recognize patients at high risk for complications in the postoperative period. The first line of defense, comprised of anatomical barriers such as the skin and mucous membranes, is easily disrupted by instrumentation such as the surgeon's scalpel or any insertion of a tube, such as a central line. This provides easy access to multitudes of pathogens in the surgical patient. The second line of defense, the nonspecific inflammatory response, assists in the elimination of pathogens and the repair of damaged tissues. The cells crucial to the nonspecific inflammatory response may be impaired by drugs such as prednisone or by certain disease states, such as diabetes. The third line of defense, the specific immune response, uses the lymphocytes as effector cells. Patients with impaired immune systems, such as cancer patients, human immunodeficiency virus-positive patients, and severely malnourished patients, are at high risk for problems with postoperative healing because of their impaired immune status. High levels of anxiety and stress can also impair the ability to fight pathogens and to repair damaged tissues. Adequate preoperative teaching programs are beneficial in reducing the stress response and therefore are important in promoting the healing process.

Application of impression cytology to the diagnosis of conjunctival neoplasms.

Conjunctival impression cytology using cellulose acetate filter paper was employed to obtain multiple samples of conjunctival epithelium from 192 normal and abnormal eyes. Modifications of an established technique were used and the impressions were stained by the Papanicolaou method and mounted on glass slides. The impressions were examined for their effectiveness in demonstrating the morphological characteristics of normal epithelium and the features of the more common conjunctival neoplasms. The technique was found to be successful at both removing cells and preserving cytologic features. It also had several advantages over other collection techniques. Overlapping cells were not a detrimental feature of the preparations from this study.

Inadvertent corneal button inversion during penetrating keratoplasty.

Inadvertent inversion of a corneal button during corneal transplantation for pseudophakic bullous keratopathy occurred with subsequent intense intraocular inflammation but a relatively compact graft. The diagnosis was made by a superficial corneal biopsy of Descemet's membrane, and a repeat corneal transplantation resulted in a clear graft and no evidence of epithelial downgrowth. Histology revealed the persistence of the donor epithelium on the inverted donor button but no residual endothelium on the externalized surface. Although laboratory attempts to duplicate an inversion of a corneal graft revealed that this occurs only with considerable difficulty, this operative complication may explain some of the unexpected primary graft failures reported in the literature.

Effects of noise and salicylate on auditory evoked-response thresholds in the chinchilla.

The combined effects of noise and sodium salicylate on auditory sensitivity were examined in the chinchilla. Sensitivity was monitored by recording the evoked response recorded with an electrode implanted in the inferior colliculus. Sodium salicylate (300 mg/kg/day), an octave band of noise centered at 500 Hz (80 or 105 dB SPL), or both of these agents were delivered for 15 days. Threshold testing was performed at 7 frequencies before, during, and after exposure to the ototraumatic agent(s). The salicylate alone caused an average temporary threshold shift of less than 10 dB and essentially no permanent shift. Animals exposed to noise alone had temporary and permanent threshold shifts which were not significantly different from those observed in animals exposed to noise plus salicylate. The data suggest that a single daily injection of sodium salicylate, resulting in peak serum salicylate concentrations of 28 to 34 mg% 2 to 4 hours after delivery, does not exacerbate the temporary or permanent threshold shifts induced by 15-day, 24-hour-per day exposure to either a moderate- or high-level, low-frequency noise. A second series of experiments utilizing a higher dose of salicylate (450 mg/kg/day) was not completed due to a high mortality rate among subjects that received salicylate and were exposed to noise. This result was consistent with other recent examinations of the interaction of these agents.

Concentration of salicylate in serum and perilymph of the chinchilla.

The concentration of salicylate in serum and perilymph was measured in chinchillas after intraperitoneal administration of sodium salicylate. Serum salicylate concentration peaked 2 to 4 hours after a single injection. Clearance was approximately complete after 16 hours. The within-subject variability of serum concentration 4 hours after injection was very low. Subject weight significantly affected serum salicylate concentration, with heavier animals showing higher serum levels. The relationship of perilymph to serum salicylate concentration was approximately linear, with a high correlation between measures.

Effects of sodium salicylate on evoked-response measures of hearing.

The effects of sodium salicylate on auditory sensitivity, frequency selectivity, and temporal resolution were monitored in chinchillas using evoked responses recorded from the inferior colliculus. Administration of sodium salicylate (450 mg/kg/day for 5-15 days) resulted in serum salicylate levels of 25-50 mg/100 ml. The salicylate administration caused elevation of evoked response thresholds (up to 30 dB), mainly at the high frequencies. Frequency selectivity, as estimated by the Q10 dB value of evoked-response tuning curves, was poorer at 4 kHz during drug administration than during the no drug (control) condition. Temporal resolution, as estimated by recovery from forward masking was not significantly poorer during salicylate administration than before administration. However, there was a trend toward longer recovery in animals with large threshold shifts. These results are consistent with models suggesting that salicylate affects the auditory system at the level of the organ of Corti. They also suggest that while the changes in hearing that occur after salicylate administration are consistent with those seen in sensorineural hearing loss, the changes in hearing in the chinchilla are small enough to preclude the use of the drug as a practical model for sensorineural loss.

The effects of different anesthetics on blood steroid concentrations in domestic tom-cats.

Testosterone and androstenedione were measured in the plasma of mature tom-cats before, during and after anesthesia with thiopentone, ketamine, xylazine and alphaxolone/alphadolone. Samples were collected via an indwelling jugular catheter at 30 min intervals before anesthesia (5 samples) and during the recovery phase (8 samples), and at intervals of 15 min during anesthesia (7 samples). Thiopentone and ketamine anesthesia significantly depressed testosterone and androstenedione concentrations during and after anesthesia. Xylazine significantly increased testosterone concentrations during anesthesia but they returned to pre-anesthetic concentrations during recovery. Androstenedione concentrations were significantly depressed during the recovery phase from xylazine anesthesia. Alphaxolone/alphadolone anesthesia had no significant effect of testosterone concentrations but significantly increased and androstenedione concentrations during anesthesia and recovery. Testosterone and androstenedione concentrations in cats were significantly altered by these 4 commonly used anesthetics and this must be taken into account if hormone concentrations are measured while cats are anesthetised.

Fetal and material ovine placental lactogen during hyperglycaemia, hypoglycaemia and fasting.

Hyperglycaemia was produced in chronically catheterized fetal lambs and pregnant-ewes by the infusion of glucose into the fetus. Plasma concentration of placenta lactogen did not change significantly in either fetal or maternal circulation. Fetal and maternal hypoglycaemia was induced by administration of insulin to the fetus and ewe separately. Plasma concentrations of placental lactogen in the fetus did not change significantly but maternal plasma concentrations fell slightly after hypoglycaemia in either fetus or ewe. Plasma concentrations of placental lactogen rose in both the ewe and fetus during prolonged fasting of the ewe. These results neither confirm nor refute a role for placental lactogen in intermediary metabolism of the pregnant ewe and fetus but glucose concentration alone is unlikely to be a significant factor in the control of secretion of this hormone.

Increase in placental lactogen and somatomedins after nephrectomy.

To investigate the relationship between renal agenesis and fetal growth retardation, 6 fetal sheep underwent bilateral nephrectomy and carotid artery catheterization between 105 and 125 days of gestation. Five fetal sheep were catheterized at a similar age as controls and all but one were delivered between 134 days and 147 days gestation. The weights of the fetuses did not differ significantly but the nephrectomized fetuses were shorter than their controls (P less than 0.01). Hydranencephaly was observed in two nephrectomized animals and the mean brain weight was reduced in this group (P less than 0.01). Fetal lung weights were likewise reduced (P less than 0.01). The mean plasma concentrations of maternal and fetal immunoreactive insulin and prolactin did not differ significantly in the two groups, nor did fetal ovine growth hormone and maternal ovine placental lactogen, also measured by radioimmunoassay. However, there were greater concentrations of ovine placental lactogen in the plasma of the nephrectomized lambs than in the controls (P less than 0.005). Somatomedin-like receptor activity was measured by receptor assay using [125I] multiplication-stimulating activity. The mean activity in unextracted serum from nephrectomized lambs was greater than that of the controls (p less than 0.05). When the fetal serum was chromatographed on Sephadex G-150 and the eluted fractions assayed for somatomedin-like activity three peaks of activity were observed. Two, with indicated molecular sizes of approximately 100,000 and 10,000 were greater in serum from nephrectomized animals than from the controls (P less than 0.01). The increased concentrations of placental lactogen and somatomedins after nephrectomy suggest that the kidney has a role in clearance of these hormones in the fetus. The growth retardation after fetal nephrectomy may be due to increased binding of somatomedin peptides by serum proteins or to an inhibition of somatomedin action by an unidentified serum component.