Although most patients with obstructive sleep apnea (OSA) are obese, it is not known how obesity contributes to airway collapse during sleep. The purpose of this study was to determine whether the volume of adipose tissue adjacent to the pharyngeal airway in humans is related to the degree of OSA. We studied 30 subjects, nine without OSA and 21 with OSA; two subjects were studied before and after weight loss. Adipose tissue was detected with magnetic resonance imaging using T1-weighted spin echo sequences. The volume of adipose tissue adjacent to the upper airway was determined by measuring the volume of all pixels in the intensity range of adipose tissue within the region bounded by the ramus of the mandible, the spine, the anterior border of the soft palate, and the hard palate. Polysomnography was performed with conventional techniques. All subjects had a collection of adipose tissue adjacent to the upper airway; the volume of this adipose tissue correlated with the number of apneas plus hypopneas per hour of sleep (r = 0.59, p < 0.001). Both patients who lost weight and had fewer apneas and hypopneas had a marked decrease in the pharyngeal adipose tissue volume. We conclude that adipose tissue is deposited adjacent to the pharyngeal airway in patients with OSA and that the volume of this tissue is related to the presence and degree of OSA.
The objective of this study was to assess the impact on pregnancy outcome of excising hydrosalpinx(ges) in patients with repeated in-vitro fertilization (IVF) failures. A group of 15 patients who had previously undergone failed IVF attempts and had unilateral or bilateral hydrosalpinx was subjected to an operative laparoscopy with excision of the affected tube(s). Of these, 10 patients underwent a unilateral salpingectomy and five had a bilateral salpingectomy. Stimulated cycles of IVF and/or cryo-thaw cycles were then carried out post-salpingectomy and the results were compared to those of pre-salpingectomy cycles. There was no statistically significant difference between the number of mature eggs retrieved, peak oestradiol concentrations, number of days to human chorionic gonadotrophin administration, or number of pre-zygotes frozen in the stimulated cycles pre- versus post-salpingectomy. Pre-salpingectomy, 15 patients underwent 38 stimulated cycles and eight patients underwent 14 cycles with cryopreserved-thawed embryos, achieving one pregnancy from a fresh transfer that resulted in a miscarriage. Post-salpingectomy, eight patients underwent 12 stimulated cycles, achieving five clinical pregnancies (two miscarriages and three ongoing pregnancies, i.e. either delivered or a pregnancy > or = 20 weeks), and nine patients underwent 10 cycles with cryopreserved-thawed embryos, achieving four clinical pregnancies (one miscarriage and three ongoing). We conclude that excision of hydrosalpinx(ges) improves the pregnancy potential after IVF, and that new and repeat IVF patients should be counselled accordingly.
Although anatomic lesions and obesity can produce obstructive sleep apnea (OSA), most subjects with OSA have no recognizable anatomic lesion. We hypothesized that the occurrence of OSA is related to the size of the region enclosed by the mandible and the degree of obesity. We studied 30 subjects with a range of OSA and obesity with magnetic resonance imaging (MRI). MRI was performed with T-1 weighted sequences. Nocturnal polysomnography was performed in all subjects. Univariate regression analysis indicated there was a significant correlation between the number of apneas and hypopneas per hour of sleep (AH/h) and (1) the area enclosed by the mandible ramus (AMR1) (r = 0.48, p < 0.01) and (2) the distance from the teeth to the posterior mandible ramus (r = 0.39, p < 0.05). Stepwise multiple regression analysis indicated that weight, AMR1, and height explained 69% of the variance of AH/h (r2 = 0.69). We conclude that the occurrence of OSA in these subjects is related to the size of the region enclosed by the mandible as well as to their weight.
A study was made of early luteal function (up to Day 6) in cyclic and pregnant heifers and also in older, subfertile cows. There were no differences in vivo or in vitro between cyclic and pregnant heifers, indicating no luteotrophic effect of the embryo at this stage, but the increase in postovulatory peripheral progesterone concentrations was delayed (P less than 0.01) and occurred more slowly (P less than 0.001) in the subfertile cows than in the heifers. The corpora lutea of the subfertile cows were heavier (P less than 0.001) than those of the heifers on Day 6. Basal progesterone production by dispersed luteal cells was similar between heifers and subfertile cows, but there was a difference (P less than 0.001) in the pattern of response to exogenous LH and PGE-2. Cells from subfertile cows were less sensitive to the stimulatory effects of PGE-2 and although LH increased (P less than 0.001) progesterone production by all cells, this stimulation by a low dose of LH was inhibited by PGE-2 in luteal cells from subfertile cows. This effect did not occur in the luteal cells from heifers. These results indicate the possibility that luteal inadequacy, due to a diminished response to circulating luteotrophic hormones, may contribute to embryo mortality in subfertile cows.
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