Effects of Non-Cavity-Distorting Intramural Fibroids on IVF Outcomes in Patients with Recurrent IVF Failure: Does Myomectomy Change IVF Outcomes ?

Background

Uterine fibroids are the most common benign smooth muscle tumors of the uterus. However, there is no consensus on whether myomectomy improves IVF success in women with non-cavity-distorting intramural fibroids. The aim of this study was to compare the IVF and pregnancy outcomes of women who had non-cavity-distorting intramural fibroids and underwent myomectomy vs women who had intramural fibroids, but did not undergo myomectomy.

Methods

A retrospective cohort study at Acibadem Maslak Hospital, IVF Center, between 2019 and 2020. Data of 128 women aged between 25 and 43 years who have at least 2 intramural non-cavity-distorting fibroids of 2-6 cm in size were used. All patients had at least two IVF failure. The intervention group comprised women who decided to proceed to myomectomy before IVF (Group 1, n = 56). The control group was established women with intramural fibroids who reject myomectomy (Group 2, n = 71).

Results

In regard to IVF result parameters and perinatal outcomes, there was no statistically significant difference between the two groups. Between study groups, there were no statistically significant differences in the perinatal outcomes. Myomectomy surgery did not increase miscarriage and biochemical pregnancy rate (odds ratio (OR) 0.9; 95% confidence interval (CI) 2.8-3.7).

Conclusion

Myomectomy does not impact on pregnancy or live birth rates substantially, according to the results of this study.

Alterations of the thioredoxin system during subarachnoid hemorrhage-induced cerebral vasospasm

BACKGROUND

The exact underlying pathogenic mechanisms and effective preventive or therapeutic interventions for cerebral vasospasm remain obscure. The thioredoxin (Trx) system performs important functions in the central nervous system including neurotrophic and neuroprotective actions. There is no study directly investigating the effects of subarachnoid hemorrhage (SAH) induced cerebral vasospasm on the Trx system in the literature.

METHODS

Sixteen male New Zealand rabbits were randomly divided into two groups of eight rabbits each: a control group and a SAH group. The control group, (n = 8) was a sham surgery group in which SAH was not induced. In the SAH group, (n = 8), the SAH protocol was used to induce cerebral vasospasm. The brain and brainstem were removed and each brainstem was cut coronally into two pieces: an anterior part that contains basilar artery and a dorsal part that contains brainstem tissue. The brainstem tissue thioredoxin-1(Trx1), thioredoxin-2 (Trx2), thioredoxin reductase (TrxR), thioredoxin reductase-1 (TrxR1), thioredoxin-interacting protein (TXNIP) levels were investigated. Total oxidant status (TOS), total antioxidant status (TAS), malondialdehyde levels (MDA) and tumor necrosis factor alpha (TNF-alpha) levels were investigated for determining the oxidative-antioxidative status of the related brain tissues. Basilar artery segments were investigated for cross-sectional area and wall thickness measurements.

RESULTS

SAH statistically significantly reduced the tissue levels of Trx1 (p < 0.01) and TrxR (p < 0.01). Trx2 levels were not significantly altered after SAH (p > 0.05). SAH significantly reduced the expression of TrxR1 (p < 0.01) and significantly increased the expression of TXNIP (p < 0.01) when compared with controls. TOS levels and MDA levels significantly increased after SAH (p < 0.01) and TAS levels significantly reduced after SAH (p < 0.01). TNF-alpha levels significantly increased after SAH (p < 0.01). SAH-induced cerebral vasospasm significantly (p < 0.05) increased the wall thickness and reduced the mean cross-sectional area of the basilar artery (p < 0.05).

CONCLUSIONS

The Trx system seems to be negatively affected by the simultaneously interrelated enzymatic alterations during cerebral vasospasm.

The effect of Ba2+ on the nitrergic mechanism in the isolated frog lung preparation

1. The present study was undertaken to investigate effects of Ba2+ on the isolated frog lung strips depolarized by 20 mM K+ in Ca2+ free Ringer solution. 2. Ba2+ produced monophasic relaxant response, whereas Ca2+ induced biphasic response consisting of a transient relaxation and a marked contraction. Both kinds of relaxation were inhibited completely by L-NOARG. L-arginine reversed the action of L-NOARG. 3. Ferrous sulfate, pyrogallol, hydroquinone, and vanadate reduced the Ba(2+)-induced relaxation in a concentration-dependent manner. 4. These findings suggest that Ba(+)-induced relaxation may fully be mediated by the nitrergic mechanism and the effect of Ba2+ on the nitric oxide synthase may be more selective than Ca2+.

Distinction of structural reorganisation and ligand binding in the T<==>R transition of insulin on the basis of allosteric models

Two allosteric models are presented for the T<==>R transition of insulin hexamers in the presence of phenolic ligands which are based on existing experimental information. The transition mainly involves residues 1-8 of the B-chain, i.e. 15% of the molecule, which are extended in the T- and helical in the R-state. The main facts to be accounted for are: 1) the transition is undergone trimer-wise; 2) the transition of the second trimer is disadvantaged compared to the first one; 3) the subunits of a trimer undergo transition in a cooperative process; 4) binding sites for phenolic ligands only exist in R3 trimers; 5) ligands shift the equilibrium by arresting the R-state; 6) the ligand is accommodated in a pocket made up between two adjacent subunits; 7) binding one ligand molecule extends the lifetime of the two other binding sites of a trimer; 8) only ligand-free trimers can undergo transitions. The two models allowed for CD spectroscopic titrations of zinc and cobalt insulin with phenol and m-cresol to be assessed in terms of structural reorganisation and ligand binding, and for the respective standard free energy differences to be calculated. delta G degrees for the reorganisation of the first timer in zinc-insulin is about 8 kJ/mol, and for that of the second trimer, 21kJ/mol. The corresponding values for cobalt-insulin are 12 and 24 kJ/mol, respectively. For both zinc- and cobalt-insulin, the delta G degrees for phenol and m-cresol binding is about -18 kJ/mol. Both models are equally compatible with the titration data.