Diagnostic accuracy of hysterosalpingo-foam sonography for assessment of fallopian tube patency in infertile women.

RESEARCH QUESTION: What is the diagnostic accuracy of hysterosalpingo-foam sonography (HyFoSy), using two-dimensional ultrasound in tubal patency assessment in infertile women compared with laparoscopy with dye chromotubation? DESIGN: This prospective study was conducted at My Duc Hospital, Vietnam. Infertile women aged 18 years or older, who were scheduled for laparoscopy, were included. Visual Analogue Scale (VAS) score for perception of pain during HyFoSy was used. Laparoscopy was carried out on the same day. Clinicians undertaking laparoscopy were blinded to HyFoSy results. Sensitivity, specificity, negative and positive predictive value, and 95% confidence intervals were calculated. A sample size of 455 women (n = 910 fallopian tubes) was needed to demonstrate a fluctuation hypothesis, not exceeding 6%, for sensitivity and specificity (power 0.80, two-sided alpha 5%, loss to follow-up 5%). RESULTS: Between 2019 and 2022, 455 participants were recruited. Hysterosalpingo-foam sonography was unsuccessfully carried out in six participants. Two withdrew their consent. Data analysis was conducted on the remaining 447 participants (n = 868 fallopian tubes). The sensitivity and specificity of hysterosalpingo-foam sonography compared with laparoscopy were 0.75 (95% CI 0.71 to 0.79) and 0.70 (95% CI 0.65 to 0.74), respectively. Hysterosalpingo-foam sonography gave a positive predictive value of 0.76 (95% CI 0.73 to 0.80) and negative predictive value of 0.68 (95% CI 0.64 to 0.73). A total of 42.8% of women reported a VAS score of no pain. No adverse event was reported. CONCLUSION: Compared with laparoscopy with dye chromotubation, two-dimensional HyFoSy is a well-tolerated, reliable technique for assessing tubal patency.

Cervical pessary versus vaginal progesterone in individuals with a singleton pregnancy and a short cervix: a randomized controlled trial.

BACKGROUND: For asymptomatic individuals with a singleton pregnancy and a short cervix, vaginal progesterone significantly decreases the risk of PTB and improves perinatal outcomes. Cervical pessary is another option that has been evaluated with inconclusive results. There is; however, a lack of head-to-head comparisons between pessary and vaginal progesterone in this high risk population. OBJECTIVE: This randomized controlled trial (RCT) aims to compare the effectiveness of pessary and vaginal progesterone for the prevention of PTB in individuals with a singleton pregnancy and a CL ≤25 mm. STUDY DESIGN: We conducted an open-label, multi-center, RCT (NCT04300322) at three hospitals in Vietnam. Asymptomatic individuals with a singleton pregnancy and a CL ≤25mm (at 16 to 22 weeks) were randomized (1:1 ratio) to receive either an Arabin® cervical pessary or 200-mg vaginal progesterone daily. Primary outcome was PTB <37 weeks of any cause. Secondary outcomes were maternal and neonatal complications. We planned to recruit 804 women to assess a 10% absolute risk reduction in PTB <37 weeks (alpha-error 0.05, power 80%, 5% lost to follow-up). In view of the potential harm of pessary on perinatal mortality and PTB <28 weeks reported recently in two recent trials, our study was halted on June 2023. Analysis was by intention-to-treat. RESULTS: Between May 2020 and May 2023, we randomized 301 participants to pessary (N=150) or vaginal progesterone (N=151). Seven participants withdrew consent and 13 were lost to follow-up, resulting in 281 participants available for analysis (pessary group N=139; vaginal progesterone group N=142). The primary outcome, any PTB <37 weeks rate, occurred in 15.1% in the pessary group versus 14.1% in the vaginal progesterone group (RR 1.07; 95% CI, 0.61 to 1.9). PTB <28 weeks and perinatal death rates were higher in the pessary group, although these differences did not reach statistical significance (7.9% versus 4.2%, RR 1.87; 95% CI, 0.71 to 4.9 and 4.3% versus 2.8%, RR 1.5; 95% CI, 0.34 to 9.2; respectively). Vaginal discharge was significantly more frequent in the pessary group. CONCLUSION: In this prematurely halted RCT involving individuals with a singleton pregnancy and a CL ≤25 mm, neither cervical pessary nor vaginal progesterone was found to be superior in the prevention of PTB <37 weeks. However, vaginal progesterone was associated with non-significantly lower rates of PTB <34, <28 weeks and perinatal death.

A Mn-sensing riboswitch activates expression of a Mn2+/Ca2+ ATPase transporter in Streptococcus.

Maintaining manganese (Mn) homeostasis is important for the virulence of numerous bacteria. In the human respiratory pathogen Streptococcus pneumoniae, the Mn-specific importer PsaBCA, exporter MntE, and transcriptional regulator PsaR establish Mn homeostasis. In other bacteria, Mn homeostasis is controlled by yybP-ykoY family riboswitches. Here, we characterize a yybP-ykoY family riboswitch upstream of the mgtA gene encoding a PII-type ATPase in S. pneumoniae, suggested previously to function in Ca2+ efflux. We show that the mgtA riboswitch aptamer domain adopts a canonical yybP-ykoY structure containing a three-way junction that is compacted in the presence of Ca2+ or Mn2+ at a physiological Mg2+ concentration. Although Ca2+ binds to the RNA aptamer with higher affinity than Mn2+, in vitro activation of transcription read-through of mgtA by Mn2+ is much greater than by Ca2+. Consistent with this result, mgtA mRNA and protein levels increase ≈5-fold during cellular Mn stress, but only in genetic backgrounds of S. pneumoniae and Bacillus subtilis that exhibit Mn2+ sensitivity, revealing that this riboswitch functions as a failsafe 'on' signal to prevent Mn2+ toxicity in the presence of high cellular Mn2+. In addition, our results suggest that the S. pneumoniae yybP-ykoY riboswitch functions to regulate Ca2+ efflux under these conditions.

Phospholipase A2 from krait Bungarus fasciatus venom induces human cancer cell death in vitro.

BACKGROUND: Snake venoms are the complex mixtures of different compounds manifesting a wide array of biological activities. The venoms of kraits (genus Bungarus, family Elapidae) induce mainly neurological symptoms; however, these venoms show a cytotoxicity against cancer cells as well. This study was conducted to identify in Bungarus fasciatus venom an active compound(s) exerting cytotoxic effects toward MCF7 human breast cancer cells and A549 human lung cancer cells. METHODS: The crude venom of B. fasciatus was separated by gel-filtration on Superdex HR 75 column and reversed phase HPLC on C18 column. The fractions obtained were screened for cytotoxic effect against MCF7, A549, and HK2 cell lines using colorimetric assay with the tetrazolium dye MTT- 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide. The primary structure of active protein was established by ultra high resolution LC-MS/MS. The molecular mechanism of the isolated protein action on MCF7 cells was elucidated by flow cytometry. RESULTS: MTT cell viability assays of cancer cells incubated with fractions isolated from B. fasciatus venom revealed a protein with molecular mass of about 13 kDa possessing significant cytotoxicity. This protein manifested the dose and time dependent cytotoxicity for MCF7 and A549 cell lines while showed no toxic effect on human normal kidney HK2 cells. In MCF7, flow cytometry analysis revealed a decrease in the proportion of Ki-67 positive cells. As Ki-67 protein is a cellular marker for proliferation, its decline indicates the reduction in the proliferation of MCF7 cells treated with the protein. Flow cytometry analysis of MCF7 cells stained with propidium iodide and Annexin V conjugated with allophycocyanin showed that a probable mechanism of cell death is apoptosis. Mass spectrometric studies showed that the cytotoxic protein was phospholipase A2. The amino acid sequence of this enzyme earlier was deduced from cloned cDNA, and in this work it was isolated from the venom as a protein for the first time. It is also the first krait phospholipase A2 manifesting the cytotoxicity for cancer cells.

In vivo, large-scale preparation of uniformly (15)N- and site-specifically (13)C-labeled homogeneous, recombinant RNA for NMR studies.

Knowledge of how ribonucleic acid (RNA) structures fold to form intricate, three-dimensional structures has provided fundamental insights into understanding the biological functions of RNA. Nuclear magnetic resonance (NMR) spectroscopy is a particularly useful high-resolution technique to investigate the dynamic structure of RNA. Effective study of RNA by NMR requires enrichment with isotopes of (13)C or (15)N or both. Here, we present a method to produce milligram quantities of uniformly (15)N- and site-specifically (13)C-labeled RNAs using wild-type K12 and mutant tktA Escherichia coli in combination with a tRNA-scaffold approach. The method includes a double selection protocol to obtain an E. coli clone with consistently high expression of the recombinant tRNA-scaffold. We also present protocols for the purification of the tRNA-scaffold from a total cellular RNA extract and the excision of the RNA of interest from the tRNA-scaffold using DNAzymes. Finally, we showcase NMR applications to demonstrate the benefit of using in vivo site-specifically (13)C-labeled RNA.