PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “INCUBATOR”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2000

Radiant warmers versus incubators for regulating body temperature in newborn infants.

BACKGROUND: This section is under preparation and will be included in the next issue. OBJECTIVES: To assess the effects of radiant warmers versus incubators (in the neonatal period) on fluid and electrolyte balance, neonatal morbidity and mortality. SEARCH STRATEGY: The standard strategy of the Cochrane Neonatal Review Group was used. This includes searches of the Oxford Database of Perinatal Trials, Medline, previous reviews including cross references, abstracts, conference and symposia proceedings, expert informants, journal handsearching mainly in the English language. SELECTION CRITERIA: All randomised or quasi-randomised trials in which radiant warmers are compared to incubators in a neonatal population. DATA COLLECTION AND ANALYSIS: Methods used to collect data from the included studies: Each author extracted data separately, then compared and resolved differences. A referee was sought for unresolved differences. Methods used to synthesise the data : Standard method of Neonatal Review Group with the use of weighted mean difference for outcome data measured on a continuous scale. MAIN RESULTS: A statistically significant increase in insensible water loss (IWL) was shown in neonates nursed under radiant warmers (WMD 0.94g/Kg/day, 95% CI 0.48, 1.41). A trend towards increased oxygen consumption which was not statistically significant was shown for the radiant warmer group (WMD 0. 27mL/kg/min, 95% CI -0.10, 0.63). A comparison of the radiant warmers with heat shields vs incubator without heat shields showed a similar trend for increased IWL in the radiant warmer group which was not statistically significant (WMD 1.00g/kg/day, 95% CI -0.10, 2. 10). No difference was shown in the rate of oxygen consumption when radiant warmers with heat shields were compared to incubators (WMD -0.05, 95% CI -0.84, 0.74). REVIEWER'S CONCLUSIONS: Radiant warmers result in increased IWL compared to incubators which needs to be taken into account when calculating daily fluid requirements.The results of this review do not provide sufficient evidence on important outcomes with the use of radiant warmers vs incubators to guide clinical practice. Further randomised controlled trials are required to assess the role of radiant warmers in neonatal care with particular attention to the extremely low birthweight population.

Body Temperature Regulation↗
PubMed2006

Non-ventilation during early incubation in combination with dexamethasone administration during late incubation: 1. Effects on physiological hormone levels, incubation duration and hatching events.

This study investigated the effect of non-ventilation of the incubator during the first 10 days of incubation and its combination with dexamethasone administration at day 16 or 18 of incubation on hatching parameters and embryo and post-hatch chick juvenile physiology. A total of 2400 hatching eggs produced by Cobb broiler breeders were used for the study. Blood samples were collected at day 18 of incubation, at internal pipping stage (IP), at the end of hatch (day-old chick) and at 7-day-post-hatch for T(3), T(4) and corticosterone levels determination. From 448 to 506 h of incubation, the eggs were checked individually in the hatcher every 2h for pipping and hatching. The results indicate that non-ventilation during the first 10-day shortened incubation duration up to IP, external pipping (EP) and hatch, had no effect on hatchability and led to higher T(3) levels at IP but lower corticosterone levels at 7-day-post-hatch. The injection of dexamethasone at days 16 and 18 of incubation affected hatching and blood parameters in both the ventilated and non-ventilated embryos differentially and the effect was dependent on the age of the embryo. Dexamethasone increased T(3) levels and T(3)/T(4) ratios but the effect was greater with early non-ventilation of eggs. Dexamethasone decreased hatchability but the effect was greater when injected at day 16 and especially in ventilated embryos. The effects of incubation protocols and dexamethasone treatments during incubation were still apparent in the hatched chicks until 7 days of age. The changes in T(3), T(4) and corticosterone levels observed in response to the early incubation conditions and late dexamethasone treatments in this study suggest that incubator ventilation or non-ventilation may influence the hypothalamic-pituitary-adrenal axis (HPA) regulation of stress levels (in terms of plasma corticosterone levels) and thyroid function in the embryo with impact on incubation duration, hatching events and early post-hatch life of the chick. Our results also suggest that some stages of development are more sensitive to dexamethasone administration as effects can be influenced by early incubation protocols.

Animals↗
PubMed1997

Modeling incubation temperature: the effects of incubator design, embryonic development, and egg size.

A simple model to describe the relationship between the temperature of the developing embryo, incubator temperature, embryo heat production, and thermal conductivity of the egg and surrounding air is presented. During early incubation, embryo temperature is slightly lower than incubator temperature because of evaporative cooling. However, from midincubation onwards, metabolic heat production from the embryo raises embryo temperature above incubator temperature. The extent of the rise in embryo temperature depends on thermal conductivity, which, in turn, is mainly influenced by the air speed over the egg. The importance of air speed and restrictions to air flow within artificial incubators is discussed. Exact determinations of optimum incubation temperatures from studies reported in the literature are difficult because only incubator temperatures are reported. Embryo temperatures can differ from incubator temperature because of differences in thermal conductivity between different incubation systems and differences between incubators in their ability to control temperatures uniformly. It is suggested that shell surface temperatures are monitored in experiments to investigate temperature effects to allow consistent comparisons between trials. Monitoring shell temperatures would also make it easier to translate optimum temperatures derived in small experimental incubators to the large commercial incubators used by the poultry industry. The relationship between egg temperature, the metabolism of the developing embryo and egg size is discussed.

Animals↗
PubMed2006

Effect of micro-environment maintenance on embryo culture after in-vitro fertilization: comparison of top-load mini incubator and conventional front-load incubator.

PURPOSE: To investigate the effect of microenvironment maintenance on embryo culture and clinical results using two types of incubators. METHODS: Temperature and oxygen concentration in a mini-incubator and a conventional incubator were compared following a 5-s door opening/closing procedure. Embryos of 30 in-vitro fertilization embryo transfer (IVF-ET) cases were randomly allocated to either one of the incubator, cultured, and the early-stage good embryo formation rate and the good blastocyst formation rate were compared, as indicators for micro-environment maintenance ability. RESULTS: Temperature recovery after a 5-s door opening/closing procedure was approximately 5 min for the mini-incubator and 30 min for the conventional incubator. The oxygen concentration return was significantly improved in the mini-incubator (3.0 +/- 0 min) compared with the conventional incubator (7.8 +/- 0.9 min). Both the early-stage good embryo formation rate and the good blastocyst formation rate were significantly higher in the mini-incubator (39.5% and 15.1%) than the conventional incubator (28.4% and 7.8%). CONCLUSION: The microenvironment maintenance ability of incubators appears to significantly influence the formation of good embryos.

Embryo Culture Techniques↗
PubMedDate not supplied

Do T3 levels in incubating eiders reflect the cost of incubation among clutch sizes?

Complete development of avian eggs requires external heat, inducing in most species an energetic cost of incubation for the parents. Triiodothyronine (T(3)) has been implicated in the control of the metabolic rate and is decreased during fasting in most bird species. This raises the question of the regulation of T(3) during reproduction when incubation (thus heat production) is associated with fasting (and energy sparing). In this study, plasma concentrations of T(3) were studied for different clutch sizes in incubating, as well as in nonincubating, fasting female eiders. Our results show that the T(3) levels decrease during fasting in nonincubating birds, whereas they were maintained during the incubation fast. T(3) levels increased in female eiders at hatching. The plasma T(3) level did not vary among natural clutch sizes in eiders but did so when manipulated. T(3) levels increased when eggs were added (to a maximum of six eggs, i.e., the biggest natural clutch size) or removed (to two eggs, i.e., the smallest natural clutch size). Our results suggest that (1) high T(3) levels during incubation may participate to a threshold of heat production and incubation metabolic rate in eiders despite the fact that they are fasting; (2) since T(3) is associated with the energy expenditure in birds, incubating an enlarged or reduced clutch size may lead to a higher energetic cost of incubation in eiders; and (3) the energy demand of the ducklings at hatching is probably important, as the female T(3) concentrations are then at their highest levels. Thus, any modification of the natural clutch size leads to a rise in the T(3) level of the incubating female, suggesting an additional cost of incubation. Knowing that there is no variation of T(3) levels among natural clutch sizes, this study suggests that a female eider produces a number of eggs corresponding to the energy she can invest in incubation.

Analysis of Variance↗
PubMed2001

Effect of extended pre-incubation with chlamydia pneumoniae and extended incubation with antimicrobial on the minimum inhibitory concentrations (MICs) of five antimicrobials.

There is no single standard methodology for in vitro susceptibility testing for Chlamydia pneumoniae, but many investigators pre-incubate this organism with the cell monolayer for 1 h prior to adding antimicrobial and incubating for 72 h. The aim of this study was to determine the effect of extended C. pneumoniae pre-incubation, and extended incubation in the presence of antimicrobial, on the MICs of 5 antimicrobials. MICs were determined for 5 ATCC strains of C. pneumoniae by employing similar methods as those previously described in the literature. MICs were then determined following 1, 4, 6, 20 and 24 h C. pneumoniae pre-incubation. Finally, MICs were determined following 1 and 24 h C. pneumoniae pre-incubation, and 48 and 72 h incubation with antimicrobial and organism. Extending the incubation time in the presence of antimicrobial from 48 to 72 h had little or no effect on MICs. Similarly, pre-incubation periods of less than 20 h had little effect on MICs, but MICs increased significantly with 20 and 24 h pre-incubation.

Anti-Bacterial Agents↗
PubMed2006

Incubation temperature and hemoglobin dielectric of chicken embryos incubated under the influence of electric field.

Eggs from a layer-type breeder flock (Baladi, King Saud University) between 61 and 63 weeks of age were used in 3 trials to study the effects of electric field (EF) during incubation on the internal temperature of incubation, and eggs and hemoglobin (Hb) dielectric of chicken embryos at 18 days of age. Dielectric relative permittivity (epsilon') and conductivity (sigma) of Hb were examined in the range of frequency from 20 to 100 kHz. The values of dielectric increment (Deltaepsilon') and the relaxation times (tau) of Hb molecules were calculated. The internal temperature of eggs was measured in empty (following the removal of egg contents) and fertilized eggs in trials 1 and 2, respectively. The level of the EF was 30 kV/m, 60 Hz. EF incubation of embryos influenced the temperature of incubation and electrical properties of Hb molecules and did not influence the temperature of incubation and internal environment of eggs when empty eggs were incubated. EF incubation of fertilized eggs significantly raised the temperature of incubation, egg air cell, and at the surface of the egg yolk by approximately 0.09, 0.60, and 0.61 degrees F, respectively and Hb epsilon', sigma, Deltaepsilon', and tau as a function of the range of frequency of 20 to 100 kHz when compared with their counterparts of the control group. It was concluded that the exposure of fertilized chicken eggs to EF of 30 kV/m, 60 Hz, during incubation altered dielectric properties of Hb and that probably affected cell to cell communication and created the right environment for enhancing the growing process and heat production of embryos consequently increasing the temperature of the internal environment of the egg, and incubation.

Animals↗
PubMed1991

Hatchability, hematological indices, and growth of turkey embryos incubated at high altitude with supplemented oxygen during the first and fourth weeks of incubation.

Turkey eggs were incubated at high altitude (1,700 m). Hatchability, hematology, and growth data were analyzed for the following treatments: 1) eggs receiving supplemented oxygen (SO) during the 1st wk of incubation (control eggs received no SO during the 1st wk); 2) eggs receiving SO during the 4th wk (control eggs received no SO during the 4th wk); and 3) the interaction effect of oxygen the 1st or 4th wk with SO the 1st and 4th wk or with no SO. Data analysis was carried out using orthogonal contrasts. Exposing incubating turkey embryos to oxygen the 1st wk or the 4th wk of incubation improved hatchability significantly (P less than or equal to .05) compared with the remaining treatments. When SO was given during the 4th wk of incubation, hemoglobin concentration in embryos decreased (p less than or equal to .05) during pipping compared with that of embryos without SO the 4th wk. Hemoglobin was increased (P less than or equal to .05) by increasing red blood cell numbers if SO was not given during Week 4, otherwise, the embryos increased (P less than or equal to .05) in mean cellular hemoglobin to increase hemoglobin. When oxygen was supplemented the 1st wk of incubation, reticulocyte maturation was slowed (P less than or equal to .05) compared with no SO the 1st wk. Oxygen exposure during the 1st wk or 4th wk of incubation reduced (P less than or equal to .05) body weights of embryos during pipping and at hatching compared with those of embryos in the remaining treatments. Oxygen supplementation during Week 4 affected (P less than or equal to .05) heart growth at the prenatal, internal pipping, and postnatal stages of respiration.(ABSTRACT TRUNCATED AT 250 WORDS)

Altitude↗
PubMed2001

Comparative clinical evaluation of a prototype non-electric transport incubator and an electrical infant incubator in a neonatal unit.

A new non-electric transport incubator has been developed for transferring babies between health facilities in developing countries. The temperature performance of this prototype was compared with a commercial electric incubator. The warm-up time for the prototype was 51.8 min, compared with 48.1 min for the electric incubator. Forty-five non-distressed premature babies, aged 24-72 h, with a gestational age of less than 37 weeks, were continuously evaluated for a 2 h period. Twenty-five babies, with a mean weight of 2073 g (range 1500-2500 g), were studied in the prototype, and 20 babies, with a mean weight of 2076g (range 1550-2500 g), were studied in the electrical incubator. The rectal and abdominal skin temperature, heart rate, oxygen saturation and respiratory rate of the babies were recorded. The temperature, oxygen and humidity level of the canopy and the room temperature were also measured. The SaO2, heart rate and respiratory rate were within the normal range (in the prototype: 96.5%, 130.5 beats min(-1) and 43 breaths min(-1), respectively; and, in the electric incubator: 96.5%, 128.5 beats min(-1) and 40 breaths min(-1), respectively). No evidence of carbon dioxide narcosis, hypoxia, acidosis or adverse thermoregulatory behaviour were observed in the two groups. The mean rectal temperature for both groups was within the range 36.5 degrees C-37.5 degrees C. There was no significant difference between the measurements of the two groups. The level of oxygen inside the canopy was 21%, and no decrease was observed. The new nonelectric transport incubator confirmed its safety and efficiency in providing a warm environment for non-distressed premature babies over a 2 h period.

Body Temperature Regulation↗
PubMed1980

Parasitological diagnosis of onchocerciasis: comparisons of incubation media and incubation times for skin snips.

Tissue culture fluid NCTC 135 (Hank's base) was compared to water and to saline as incubation media for the detection of microfilariae of Onchocerca volvulus in skin snips. NCTC 135 allowed detection of significantly more positive persons than did water (P less than 0.001) or saline (P less than 0.05) when two snips per person were incubated for periods of 0.5 or 24 hours. In addition, snips containing microfilariae were incubated in NCTC 135 or in saline and the number of emerged microfilariae was determined at various intervals of time up to 24 hours. After incubation, snips were either fixed in 10% formalin, serially sectioned, and the microfilariae counted, or they were digested in collagenase solution to free unemerged microfilaire. Of the total number of microfilariae present in the snips, 43.9% +/- 18.5, 80.2% +/- 22.2, 83.0% +/- 19.5, and 85.3% +/- 18.0 had emerged by 0.5, 4, 8, and 24 hours of incubation, respectively. Of the microfilariae that remained in the skin after incubation, most were located deep in the dermis.

Adult↗
PubMed1987

Induction of maternal behavior in incubating and non-incubating hens: influence of hormones.

Maternal responses and variations in plasma levels of prolactin and testosterone have been studied in incubating and in non-incubating, non-laying hens during forced adoption experiments. The results demonstrate the ability of incubating hens to display complete maternal behavior as early as the 10th day of incubation after being exposed to stimulation by chicks during one night. Maternal responses also emerged in non-laying hens but more gradually. In both groups, a decline in plasma testosterone occurred after the introduction of the chicks and, in the incubating hens, prolactin levels fell as they abandoned their nests.

Animals↗
PubMed1989

Influence of hematoporphyrin derivative concentration, incubation time, temperature during incubation and laser dose fractionation on photosensitivity of normal hemopoietic progenitors or leukemic cells.

Photodynamic therapy represents a new approach for the local control of cancers. It has recently been claimed that photodynamic therapy mediated by hematoporphyrin derivative (HPD) is selectively more efficient for killing leukemic cells than normal progenitors. To improve this effect, we studied the influence of hematoporphyrin dose, temperature during incubation and/or treatment, hematoporphyrin derivative incubation time, and fractionation of the argon laser light (488-514 nm) used for hematoporphyrin stimulation. Plating efficiency calculated after a 7-day period of growth on collagen gel medium showed a dose-dependent phototoxicity of HPD reaching 0.01% for normal hemopoietic progenitors and 0.001% for leukemic cells (dose = 12.5 micrograms/ml). The 10:1 ratio of normal hemopoietic progenitors to leukemic cells was also found to be the same or increased when temperature was 37 degrees C during incubation and 4 degrees C during laser irradiation. Similar results were also found when incubation time was varied from 75-120 min, or when laser irradiation dose was fractionated into 2 or 3 periods. The ratio of normal progenitors to leukemic cells reached 100:1 when 75 J/cm2 were fractionated into 3 periods after an incubation time of 120 min with 10 micrograms/ml HPD. Selectivity in photodynamic treatment seems to occur between normal hemopoietic progenitors and leukemic cells. The mechanism of this selectivity remains unclear, but experiments with the fractionated irradiation dose suggest that as in radiotherapy, better potentially lethal damage repair in normal cells could be a factor for selectivity in photodynamic therapy. Our results obtained with leukemic cells are fully in agreement with data in the literature concerning similar experimental models.

Animals↗
PubMed1991

Paradoxical shortening of scrapie incubation times by expression of prion protein transgenes derived from long incubation period mice.

Prolonged incubation times for experimental scrapie in I/LnJ mice are dictated by a dominant gene linked to the prion protein gene (Prn-p). Transgenic mice were analyzed to discriminate between an effect of the I/LnJ Prn-pb allele and a distinct incubation time locus designated Prn-i. Paradoxically, 4 independent Prn-pb transgenic mouse lines had scrapie incubation times shorter than nontransgenic controls, instead of the anticipated prolonged incubation periods. Aberrant or overexpression of the Prn-pb transgenes may dictate abbreviated incubation times, masking genuine Prn-p/Prn-i congruence; alternatively, a discrete Prn-i gene lies adjacent to Prn-p.

Animals↗
PubMed1976

The effects of ouabain and ethacrynic acid on the intracellular sodium and potassium concentrations in renal medullary slices incubated in cold potassium-free ringer solution and re-incubated at 37 degrees C in the presence of external potassium.

1. The cells in slices cut from the renal outer medulla of normally hydrated adult rats were loaded with Na and depleted of K by incubation for up to 100 min in cold iso-osmolal K-free Ringer containing 180 mM-Na. There was a continuous net cellular water loss during this time; an inverse linear relationship existed between water content and intracellular Na concentration. 2. The original intracellular Na and K concentration were restored following 60 min re-incubation in warm Ringer (37 degrees C) containing 5-9 mM-K. Restoration of cellular water content was incomplete after re-incubation for up to 120 min. 3. During incubation in cold K-free Ringer the presence of 1 mM ouabain did not affect cellular Na uptake or K and water loss. Ethacrynic acid, 1 mM, completely blocked cellular Na uptake and water loss, without affecting the intracellular K concentration at 100 min. When ouabain and ethacrynic acid were present together water loss was also prevented but intracellular Na concentration rose slightly by 100 min. 4. During re-incubation in warm K-containing Ringer 1 mM ouabain inhibited Na extrusion completely for up to 60 min while only partially preventing K uptake and further depressing the level of cellular hydration. Ouabain in the presence of 1 mM ethacrynic acid had similar effects on intracellular Na and K concentrations, but raised the level of intracellular water above that of cells in control slices. 5. Ethacrynic acid alone, 1 mM, did not interfere with Na extrusion or K uptake, but also raised intracellular water above control values. 6. The results obtained are discussed in relation to (a) the nature of the preparation used, (b) the possible membrane transport processes occurring and their known or suggested sensitivity to ouabain and ethacrynic acid, (c) the mechanisms which may be responsible for cell volume maintenance in the medulla.

Animals↗
PubMed1991

Adaptation of homeostatic thermoregulation: comparison of incubating and non-incubating bantam hens.

Incubating and non-incubating Bantam hens were exposed to identical thoracic skin cooling to study the difference between their physiological responses with regard to thermoregulatory adaptation to incubation. Under resting conditions thoracic skin temperature (Tths) and metabolic heat production (M) were significantly higher in broody than in non-broody hens, indicating a permanently increased conductance of the brood patch. Thoracic skin cooling from 35 to 25 degrees C decreased Tths less in broody than in non-broody hens. In broody hens, these coolings induced a large, immediate increase in M, no constriction of brood patch vasculature, and a decrease in colonic temperature (Tc). This decrease in Tc triggered no further increase in M, but induced vasoconstriction in the feet. The coolings induced a smaller increase in M in the non-broody hens, accompanied by pronounced vasoconstriction, and did not affect Tc and foot temperature, Tf. The effects of more severe thoracic skin cooling (between 25 and 15 degrees C) differed much less between non-broody and broody hens. Vasoconstriction of the brood patch also occurred in the latter. It is concluded that in adaptation to incubation the thoracic skin becomes more sensitive, and its input signal becomes stronger for the control of certain effector systems of thermoregulation, allowing a controlled heat transfer to the eggs.

Adaptation, Biological↗