Experiences of the mothers of infants hospitalized in the neonatal intensive care unit (NICU).

BACKGROUND: The mother-newborn relationship is more important in neonates hospitalized in the NICU than in healthy neonates. This study was conducted to explore the experiences of the mothers of infants hospitalized in the NICU. MATERIALS AND METHODS: This qualitative study was done in 2016 by adopting a conventional content analysis approach. Thirty-five mothers in the NICUs, Imam Hossein Hospital and Fatemieh Hospital were selected. Their experiences were assessed using in-depth individual semi-structured interviews. Sampling was purposive and was continued until reaching data saturation. RESULTS: Two hundred and nine primary codes were extracted. After removing duplicates and overlaps, 95 primary codes were categorized in 8 subcategories, 2 accessory categories and 1 main category based on their appropriateness, agreement, and similarity. The accessory categories of "mothers' worries" and "mothers' hopes" were merged into a more general, abstract category named "dual feelings about the baby". CONCLUSIONS: The nurses' awareness of the mothers' experiences can help design interventions to promote the quality of care for mothers and infants in the critical period of the NICU admission.

A Comparative Study on Micro Hardness and Structural Changes of Dentin Floor Cavity Prepared by Er: YAG Laser Irradiation and Mechanical Bur.

STATEMENT OF PROBLEM: Laser irradiation makes structural and chemical changes on the dental hard tissues. These changes alter the level of solubility and permeability of dentin. PURPOSE: The aim of this study was to compare the microhardness and the structural changes in the dentin cavity floor prepared with Er: YAG laser and bur. MATERIAL AND METHODS: In this experimental study, fifteen intact human molars were selected. Two square cavities were prepared on the buccal and lingual surfaces of each tooth. One side was randomly prepared by Er:YAG laser and the other side by bur. The specimens were divided into two halves. Consequently, there were 30 samples in every group. One half was assigned for the Vickers's hardness test and the other one, for determination of Ca and P percentage and atomic elements analysis. The data were analyzed by Paired T-tests through SPSS16 (α≤o.o5). RESULTS: The means and the standard deviation of the microhardness were 69.77±25.62 and 51.33±9.31 Kg/mm(2) in the laser and bur groups, respectively. Statistical analysis showed significant differences between the two groups (p=0.017). Weight percentage of calcium in the laser cavity (65.5) was less than the bur cavities (68.21) and the difference was significant (p= 0.037). CONCLUSION: The hardness of dentin in laser group was higher than the bur group because of the higher mineral content of the dentin. The hardness and the mineral content of dentin are important factors in the bonding effectiveness of the dental materials so with laser cavity preparation, good mineral substrate are available for a better bonding.

The effect of co-spray drying with polyethylene glycol 4000 on the crystallinity and physical form of lactose.

The effect of spray drying lactose alone and in the presence of polyethylene glycol 4000 was investigated. Lactose was added to distilled water to give concentrations of 10, 20, 30 and 40g/100ml at room temperature and each spray dried in turn. Identical samples were prepared to which polyethylene glycol (PEG) 4000 was added (12% by weight of lactose) prior to spray drying. Microcalorimetric and X-ray diffraction studies showed that spray drying lactose solutions produced completely amorphous material due to rapid solidification during the spray drying process, whereas lactose suspensions yielded partially crystalline products due to crystalline material that remained in suspension. However, all the PEG/lactose (12%w/w) co-spray dried products were found to be crystalline. It can be inferred that the solidification rates of the lactose in the presence of PEG must have been slower than that of lactose alone which allowed PEG and lactose to crystallize. The PEG/lactose products that were spray dried from solution consisted of alpha-anhydrous, alpha-monohydrate, beta-lactose and PEG extended chain polymorph, whereas those formed from suspension PEG/lactose samples consisted of only alpha-anhydrous, alpha-monohydrate and extended chain PEG crystals. PEG probably caused the more concentrated lactose suspensions to crystallize slowly due to the strong hydrogen bonding between PEG and water, which allowed growth on the alpha-lactose seed crystals.

Physicochemical properties of parenteral fat emulsions containing 20% triglyceride; Intralipid and Ivelip.

The paper describes an in-depth study of the parenteral fat emulsions, Intralipid 20% and Ivelip 20%. A large number of emulsion samples from separate containers and batches was sampled. The parameters measured were droplet size (both by photon correlation and laser diffraction), pH and zeta potential. These parameters were re-measured after the emulsions were subjected to a number of accelerated stability tests (freeze-thaw cycling, autoclaving and shaking). The results demonstrate that although the Intralipid is stable, it can show some variability between separate batches. The stability of Ivelip is high, and the variability between separate batches is extremely low.

Polyhydroxybutyrate as a drug carrier.

Polyhydroxybutyrate (PHB) can be used as an alternative polymer to polylactide-glycolides for drug carrier production. It is a linear homopolymer biosynthesized by various strains of bacteria by condensation of D(-)-B-hydroxybutyric acid and used as an energy and carbon source. PHB can be obtained by extraction from bacteria or by chemical synthesis. To be suitable as drug carrier the polymer has to be biocompatible, biodegradable in certain applications, and nontoxic. PHB seems to be biocompatible and biodegrades readily to carbon dioxide in bacteria; however, in humans, the reports are few and contradictory. The polymer is nontoxic and its monomer seems to be tolerated well in relatively high concentrations. Possible applications include implants and i.m.-administered particulates for controlled release and i.v.-injected colloidal carriers for drug targeting.