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(1/92) Kinetic analysis of oral tolerance: memory lymphocytes are refractory to oral tolerance.

Oral administration of soluble Ag before immunization induces peripheral tolerance and is effective in suppressing animal models of autoimmune diseases. Although tolerance induction in primed animals is more clinically relevant, it is not well studied. Therefore, this study was designed to examine the feeding effects on different phases of the immune response. We observed that feeding a single high dose (250 mg) of OVA to OVA-primed BALB/c mice could induce OVA-specific suppression in the Ab production and T cell proliferation only at the naive and the activation phases of the immune response, whereas multiple high doses (100 mg/feed for 10 days) were effective at the effector phase. OVA-specific IL-4 production in culture supernatant was also suppressed in the tolerized groups. However, when the mice had resting memory lymphocytes, even multiple feeding regimens were not effective in tolerance induction, although multiple low doses (1 mg/feed for 10 days) partially suppressed Ab production. This phenomenon was confirmed by adoptive transfer study. Nevertheless, the reactivated memory response was suppressed partially by multiple high doses. Our findings have an important implication for understanding the mechanism of oral tolerance and for the therapeutic applications of oral tolerance to autoimmune diseases.  (+info)

(2/92) Reflex secretion of proteins into submandibular saliva in conscious rats, before and after preganglionic sympathectomy.

1. An indwelling catheter was placed in the left submandibular duct of rats, under pentobarbitone anaesthesia, and connected to an outflow cannula that emerged above the skull. 2. Saliva was collected from the outflow cannula in conscious rats, the same day after recovery from anaesthesia, under four different reflex conditions: grooming, heat exposure, rejection of a bitter tasting substance and feeding on softened chow, repeated in different orders. 3. Saliva flow was greatest for grooming and least for rejection. Protein concentrations were least with heat but much greater and similar for the other stimulations. Acinar peroxidase activity was high for feeding, intermediate for grooming and rejection, and again lowest with heat. Tubular tissue kallikrein activities were moderately low, being greatest with feeding and least with grooming. Secretory immunoglobulin A (SIgA) concentration was least with heat and similar for the other stimulations. 4. The next day, under pentobarbitone anaesthesia, the left preganglionic sympathetic trunk was sectioned (sympathetic decentralization) and, after recovery, the preceding stimulations were repeated. Flow of saliva showed little change, but protein and peroxidase concentrations and outputs decreased dramatically with grooming, rejection and feeding to levels similar to those with heat, which showed little change. Tissue kallikrein was lowered less dramatically, but the reductions in output were significant except with heat. Patterns of proteins resolved by electrophoresis changed for grooming, rejection and feeding and became similar to saliva from heat, which showed little change. No significant effects on SIgA concentrations occurred. 5. Gland weights from the sympathetically decentralized side were greater than from the intact side at the end of the experiments and histologically showed retention of acinar mucin. 6. Thus reflex sympathetic drive varied with the different stimulations; it was least during heat, but it had pronounced effects on acinar secretion of proteins during the other stimulations. At the same time this sympathetic drive had less impact on tissue kallikrein secretion from tubules and had little influence on flow or the concentration of SIgA secreted.  (+info)

(3/92) Secretion of trophic gut peptides is not different in bolus- and continuously fed piglets.

In neonates, bolus feeding is associated with greater rates of intestinal growth than is continuous feeding. We tested whether the concentrations and secretion rates of trophic gut peptides are higher in bolus-fed than in continuously fed piglets. Five 21-d-old piglets were surgically implanted with gastric, arterial and portal catheters and a portal blood flow probe. At postnatal d 30 and 31, pigs received an equal amount of primed continuous or bolus feeding of a cow's milk formula in a randomized, crossover design. During a 6-h period, portal blood flow and arterial and portal concentrations of glucagon-like peptide-2 (GLP-2), peptide YY (PYY) and gastric inhibitory polypeptide (GIP) were measured. All hormone levels were significantly increased within 1 h of the start of the experiment, independent of the feeding modality. There were no differences between bolus and continuous feeding in either the arterial concentrations or secretion rates of GLP-2, PYY and GIP. In both treatment groups, the increases in the plasma concentrations of GLP-2 and GIP after feeding were substantially greater than those for PYY. We conclude that the production or circulating concentrations of GLP-2, PYY and GIP are not significantly different in bolus- and primed continuously fed piglets.  (+info)

(4/92) Morphological diversity in digital skin microstructure of didelphid marsupials.

The purpose of this study was to investigate how didelphid marsupials have diversified in morphology of their claws and digital pads as they evolved different foraging preferences such as terrestrial, aquatic, and arboreal feeding behaviours. Both arboreal and more terrestrial didelphids have papillary ridges on the digital pads of the fore and hindfoot. In contrast, the papillary ridges on the pedal digital skin of the water opossum Chironectes minimus have been replaced by nonoverlapping, thickened epidermal scales. Chironectes also differs from the other didelphids studied in having finger tips with reduced claws and digital pads that are covered with raised epidermal scales having projecting, finger-like cones arranged radially around the perimeter of each scale. The reduced claws and unusual digit skin microstructure of Chironectes likely improve this animal's ability to recognise and identify live animal prey under water using only its sense of touch.  (+info)

(5/92) A comparison of the safety of cupfeedings and bottlefeedings in premature infants whose mothers intend to breastfeed.

OBJECTIVE: To compare the safety of cupfeeding, an alternative feeding method, to bottlefeeding, the current standard of artificial feeding in the United States, in preterm infants whose mothers intend to breastfeed. STUDY DESIGN: In a prospective, randomized crossover study, 56 infants or=34 weeks' corrected gestational age, the order of the first two non-breast oral feedings was randomized by coin toss to one cupfeeding and one bottlefeeding. Trained Neonatal Intensive Care Unit nurses provided the feedings. Heart rate, respiratory rate, and oxygen saturation were recorded at 1-minute intervals for 10 minutes before and during the feeding. Volume taken, time required to complete the feed, and any apnea, bradycardia, choking, or spitting episodes were recorded. RESULTS: Heart rate (p<0.0001) and respiratory rate (p<0.0001) increased and oxygen saturation decreased (p=0.0002) during both cup and bottlefeedings compared to pre-feeding baselines. The amount of change in these three parameters from baseline to feeding period was similar for both feeding methods. The fraction of O(2) saturation <90% during baseline compared to the study period was different between these two feeding methods (p=0.02). There was a 10-fold increase in desaturations <90% during bottlefeeds compared to no change during cupfeeds. When comparing cupfeeding periods to bottlefeeding periods, heart rates were higher (p=0.009) and oxygen saturations lower (p=0.02) during bottlefeeds. There were no differences between methods in respiratory rate, choking, spitting or apnea, and bradycardia. Volumes taken were lower (p=0.001) and duration of feeds longer (p=0.002) during cupfeedings. CONCLUSION: During cupfeedings, premature infants are more physiologically stable, with lower heart rates, higher oxygen saturations, and less desaturations, than during bottlefeedings. However, cupfed infants took less volume, over more time, than bottlefed for these initial feedings. Based on better physiologic stability and no difference in untoward effects, cupfeeding is at least as safe, if not safer, than bottlefeeding in this population. This study supports the use of cupfeeding as a safe alternative feeding method for premature infants learning to breastfeed.  (+info)

(6/92) Refeeding syndrome: effective and safe treatment with Phosphates Polyfusor.

BACKGROUND: Severe hypophosphataemia associated with refeeding syndrome requires treatment with intravenous phosphate to prevent potentially life-threatening complications. However, evidence for replacement regimens is limited and current regimens are complex and replace phosphate inadequately. AIM: To assess the effectiveness and safety of 50 mmol intravenous phosphate infusion, given as a 'Phosphates Polyfusor', for the treatment of severe hypophosphataemia in refeeding syndrome. METHODS: Patients with refeeding syndrome and normal renal function received a Phosphates Polyfusor infusion for the treatment of severe hypophosphataemia (< 0.50 mmol/L). The outcome measures were serial serum phosphate, creatinine and calcium concentrations for 4 days following phosphate infusion and adverse events. RESULTS: Over 2 years, 30 patients were treated. Following treatment, 37% of cases had a normal serum phosphate concentration and 73% had a serum phosphate concentration of > 0.5 mmol/L within 24 h. Ten patients required more than one Phosphates Polyfusor infusion. Within 72 h, 93% of cases had achieved a serum phosphate concentration of > or = 0.50 mmol/L. No patient developed renal failure. Three episodes of transient mild hyperphosphataemia were recorded. Four patients developed mild hypocalcaemia. CONCLUSIONS: This is the largest published series of the use of intravenous phosphate for the treatment of severe hypophosphataemia (< 0.50 mmol/L), and is the most effective regimen described. All patients had refeeding syndrome and were managed on general wards.  (+info)

(7/92) Functional analysis of inappropriate mealtime behaviors.

The purpose of the current investigation was to apply the functional analysis described by Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994) to the inappropriate mealtime behaviors of 15 children who had been referred to an intensive program for the assessment and treatment of severe feeding disorders. During Study 1, we conducted descriptive assessments of children and parents during meals. The results of Study 1 showed that parents used the following consequences for inappropriate mealtime behaviors: coaxing and reprimanding, allowing the child to periodically take a break from or avoid eating, and giving the child preferred food or toys following inappropriate behavior. The effects of these consequences were tested systematically in Study 2 when we conducted analogue functional analyses with the children. During alternating meals, one of the consequences typically used by parents consistently followed inappropriate child behavior. Results indicated that these consequences actually worsened behavior for 10 of the 15 children (67%). These results suggested that the analogue functional analysis described by Iwata et al. may be useful in identifying the environmental events that play a role in feeding disorders.  (+info)

(8/92) Medicare and Medicaid programs; requirements for paid feeding assistants in long term care facilities. Final rule.

This final rule permits a long term care facility to use paid feeding assistants to supplement the services of certified nurse aides under certain conditions. States must approve training programs for feeding assistants using Federal requirements as minimum standards. Feeding assistants must successfully complete a State-approved training program and work under the supervision of a registered nurse or licensed practical nurse. The intent is to provide more residents with help in eating and drinking and reduce the incidence of unplanned weight loss and dehydration.  (+info)