3 research outputs found
The cartilaginous nasal dorsum and the postnatal growth of the nose
Until now the numerous articles about nasal surgery in children and the associated
eweriments have paid little or no attention to the cartilaginous nasal dorsum. Yet the
importance of the upper lateral cartilages for the shape of the nose is well known to all
who do nasal surgery in adult patients. Inadequate correction of asymmetries of these
thin, cartilaginous, plate-like structures leads inevitably to external deviations of the
nose.
Moreover, there is no detailed description of the upper lateral cartilages in children to
be found in the literature. It has apparently been assumed that the anatomy of a child's
nose is identical to that of an adult.
Consequently, with respect to nasal surgery in children the following questions have to
be considered:
1. What is the anatomy of the cartilaginous nasal skeleton and, in particular, the
cartilaginous nasal dorsum in children?
2. What is the role of the cartilaginous nasal dorsum (upper lateral cartilages) in the
postnatal growth of the nose?
The first question is dealt with in the chapters 2 and 3, the second in the chapters 10, 11,
12 and 14. A general discussion will follow in chapter 15
Indices from flow-volume curves in relation to cephalometric, ENT- and sleep-O2 saturation variables in snorers with and without obstructive sleep-apnoea
In a group of 37 heavy snorers with obstructive sleep apnoea (OSA, Group
1) and a group of 23 heavy snorers without OSA (Group 2) cephalometric
indices, ENT indices related to upper airway collapsibility, and nocturnal
O2 desaturation indices were related to variables from maximal expiratory
and inspiratory flow-volume (MEFV and MIFV) curves. The cephalometric
indices used were the length and diameter of the soft palate (spl and
spd), the shortest distance between the mandibular plane and the hyoid
bone (mph) and the posterior airway space (pas). Collapsibility of the
upper airways was observed at the level of the tongue base and soft palate
by fibroscopy during a Muller manoeuvre (mtb and msp) and ranked on a five
point scale. Sleep indices measured were the mean number of oxygen
desaturations of more than 3% per hour preceded by an apnoea or hypopnoea
of more than 10 s (desaturation index), maximal sleep oxygen desaturation,
baseline arterial oxygen saturation (Sa,O2) and, in the OSA group,
percentage of sleep time with Sa,O2 < 90%. The variables obtained from the
flow-volume curves were the forced vital capacity (FVC), forced expiratory
and inspiratory volume in 1 s (FEV1 and FIV1), peak expiratory and peak
inspiratory flows (PEF and PIF), and maximal flow after expiring 50% of
the FVC (MEF50). The mean of the flow-volume variables, influenced by
upper airway aperture (PEF, FIV1) was significantly greater than
predicted.(ABSTRACT TRUNCATED AT 250 WORDS
The in vitro and in vivo capacity of culture-expanded human cells from several sources encapsulated in alginate to form cartilage
Abstract
Cartilage has limited self-regenerative capacity. Tissue engineering can offer promising solutions for reconstruction of missing or damaged cartilage. A major challenge herein is to define an appropriate cell source that is capable of generating a stable and functional matrix. This study evaluated the performance of culture-expanded human chondrocytes from ear (EC), nose (NC) and articular joint (AC), as well as bone-marrow-derived and adipose-tissue-derived mesenchymal stem cells both in vitro and in vivo. All cells (≥ 3 donors per source) were culture-expanded, encapsulated in alginate and cultured for 5 weeks. Subsequently, constructs were implanted subcutaneously for 8 additional weeks. Before and after implantation, glycosaminoglycan (GAG) and collagen content were measured using biochemical assays. Mechanical properties were determined using stress-strain-indentation tests. Hypertrophic differentiation was evaluated with qRT-PCR and subsequent endochondral ossification with histology. ACs had higher chondrogenic potential in vitro than the other cell sources, as assessed by gene expression and GAG content (p < 0.001). However, after implantation, ACs did not further increase their matrix. In contrast, ECs and NCs continued producing matrix in vivo leading to higher GAG content (p < 0.001) and elastic modulus. For NC-constructs, matrix-deposition was associated with the elastic modulus (R² = 0.477, p = 0.039). Although all cells--except ACs--expressed markers for hypertrophic differentiation in vitro, there was no bone formed in vivo. Our work shows that cartilage formation and functionality depends on the cell source used. ACs possess the highest chondrogenic capacity in vitro, while ECs and NCs are most potent in vivo, making them attractive cell sources for cartilage repair