A randomized controlled study comparing pain experience between a newly designed needle with a thin tip and a standard needle for oocyte aspiration.

UNLABELLED: BACKGROUND; Ultrasound-guided transvaginal oocyte retrieval is often performed under local anaesthesia on an outpatient basis. The objective of this study was to compare the overall pain experience of a newly designed reduced needle (RN) compared with a thicker standard needle (SN). METHODS: A prospective, randomized, multi-centre study was performed at four different clinics from June to December 2009. The oocyte aspiration was performed under local anaesthesia, either with a needle with a reduced diameter (0.9 mm) for the last 50 mm from the tip (RN) or with a SN (1.4 mm). A total of 257 patients were randomized (RN: n = 129; SN: n = 128). The primary endpoint was the overall pain experience self-assessed and registered by the patient on a visual analogue scale (VAS 0 mm = no pain to 100 mm = unbearable pain) immediately after the oocyte retrieval. Secondary end-points such as vaginal bleeding and several embryological parameters were also registered. RESULTS: The overall pain during the oocyte retrieval procedure was significantly lower in the RN group than in the SN group (mean 21.0 mm, SD 17.5 mm and median 19.0 mm versus mean 26.0 mm, SD 19.9 mm and median 24.0 mm; P = 0.040, difference between groups mean-5.0 mm, 95% CI: 9.7 to-0.4). This was also true when adjusting for baseline characteristics such as number of follicles, number of previous oocyte pick-up, body mass index and age, by a multiple linear regression analysis. Significantly more patients (40 of 126) had less than expected vaginal bleeding in the RN group when compared with the SN group (24 of 124; 32 versus 19%; P = 0.03 and 95% CI 1.7-23.0%). No differences were found between the two needles with regard to additional i.v. analgesia, aspiration time, oocyte recovery, fertilization, cleavage rate, number of good quality embryos, number of embryos for freezing and pregnancy rate. CONCLUSIONS: Oocyte aspiration performed with the newly designed thinner-tipped needle resulted in significantly less overall pain and less vaginal bleeding, without prolonging the retrieval procedure or influence the oocyte recovery rate, when compared with a SN. Clinicaltrials.gov: NCT00924885.

Change in heart rate variability in relation to a significant ST-event associates with newborn metabolic acidosis.

OBJECTIVE: To find whether low-to-high frequency (LF/HF) ratio of fetal heart rate (FHR) variability changes in relation to a significant ST-event during delivery, and if the change is predictive of metabolic acidosis of the newborn. DESIGN: A case-control study. SETTING: Data from a multicentre project. SUBJECTS: Acidotic and control fetuses with abnormal cardiotocography together with a ST-event in fetal electrocardiogram (ECG). METHODS: We studied intrapartum FHR variability with spectral analysis from 34 fetuses with a significant ST-event in the fetal ECG. LF/HF ratio of FHR variability was measured within a period of 1 hour before and 1 hour after a significant ST-event. Sensitivity and specificity of the change in LF/HF ratio of FHR variability in prediction of metabolic acidosis (pH < or = 7.05 and base deficit value > 12.0 mmol/l) of the newborn were described by means of the receiver operating characteristic curve. MAIN OUTCOME MEASURES: Change in LF/HF ratio of FHR in relation to a significant ST-event. RESULTS: We found that a relative change in LF/HF ratio greater than 30% in relation to a significant ST-event predicted cord arterial metabolic acidosis with a sensitivity of 89% (95% CI 68-100%) and specificity of 80% (95% CI 64-96%). CONCLUSIONS: Relative changes in LF/HF ratio of FHR variability in relation to a significant ST-event are more pronounced in fetuses born with metabolic acidosis.

Low external pH induces HOG1-dependent changes in the organization of the Saccharomyces cerevisiae cell wall.

Low environmental pH strongly affected the organization of the Saccharomyces cerevisiae cell wall, resulting in rapidly induced resistance to beta1,3-glucanase. At a molecular level, we found that a considerable amount of Cwp1p became anchored through a novel type of linkage for glycosylphosphatidylinositol (GPI)-dependent cell wall proteins, namely an alkali-labile linkage to beta1,3-glucan. This novel type of modification for Cwp1p did not require the presence of a GPI-derived structure connecting the protein with beta1,6-glucan. In addition, we found high levels of Cwp1p, which was double-anchored through both the novel alkali-sensitive bond to beta1,3-glucan and the alkali-resistant GPI-derived linkage to beta1,6-glucan. Further cell wall analyses demonstrated that Pir2p/Hsp150 and possibly other Pir cell wall proteins, which were already known to be linked to the beta1,3-glucan framework by an alkali-sensitive linkage, were also more efficiently retained in the cell wall at pH 3.5 than at pH 5.5. Consequently, the alkali-sensitive type of linkage of cell wall proteins to beta1,3-glucan was induced by low pH. The low pH-induced alterations in yeast cell wall architecture were demonstrated to be dependent on a functional HOG1 gene, but not on the Slt2p-mediated MAP kinase pathway. Consistent with this observation, DNA microarray studies revealed transcriptional induction of many known high-osmolarity glycerol (HOG) pathway-dependent genes, including four cell wall-related genes, namely CWP1, HOR7, SPI1 and YGP1.