Routine Preparation Research Articles

Improved extraction efficiency of radioactive copper produced via accelerator neutrons method through phosphate buffer-enhanced column pre-treatment

We report a straightforward and robust method for isolating medical copper radioisotopes 64Cu and 67Cu, generated by an accelerator neutrons technique from natZn(n, x). This study reveals the key role of a phosphate buffer pre-treatment of the cation exchange column in the separation process. Incorporating the phosphate buffer into the column pre-treatment markedly enhances the retention of copper isotopes within the column throughout the separation procedure. This approach yields a remarkably high-purity radioactive copper sample with a high extraction efficiency of 94.4 (1.5) % of the initially produced copper, all within a relatively short experimental timeframe of approximately 5 h for 100 g of starting material. This single-step separation scheme is reproducible across a range of starting material target sizes, from small (10 g) to large (100 g). The copper radioisotopes obtained are suitable for use in pre-clinical studies. Thus, this approach offers a more effective means for routine preparation of copper radioisotopes.

Profiles of differential expression of miRNAs in the late stage of red blood cell preservation and their potential roles

ObjectiveTo detect the differentially expressed regulatory miRNAs in the late stage of red blood cell (RBC) preservation and predict their roles. MethodsSuspended RBCs with different storage periods of 35 day, 42 day, and 50 day were collected for routine blood tests, RNA extraction, and preparation of small RNA sequencing libraries. The constructed libraries were sequenced and the biological functions of differential miRNAs in RBCs in the late storage were analyzed by bioinformatics. ResultsRoutine indicators of RBCs in the late stage were not significantly affected by preservation time. The Pearson correlation analysis performing on RBC miRNAs with different storage days revealed that RBC miRNAs changed with the increase of storage days. RBC miRNAs from day 35 (D35), day 42 (D42) and day 50 (D50) showed significant differences (P < 0.05). Compared RBC miRNAs from D42 with these from D35, there were 690 up-regulated miRNAs and 82 down-regulated miRNAs; compared RBC miRNAs from D50 with these from D35, there were 638 up-regulated miRNAs and 123 down-regulated miRNAs; compared RBC miRNAs from D42 with these from D50, there were 271 up-regulated miRNAs and 515 down-regulated miRNAs. GO enrichment analysis of target genes of differential miRNAs were mainly involved in cell metabolism, biosynthesis, protein modification, gene expression and transcriptional regulation of biological processes. KEGG pathway enrichment analysis of miRNA target genes showed that differential miRNA target genes were closely related to pathways in cancer. ConclusionMiRNAs were differentially expressed in the late stage of RBC preservation, and may be involved in various biological processes, especially cancer.

Risk factor stratification for urgent and nonurgent transfusion in patients giving birth

BackgroundA common approach to attempt to reduce maternal morbidity from hemorrhage is to recognize patients at increased risk, and to make advance preparations for possible blood transfusion in these patients. Preparation may consist of a hold clot, type, and screen, or crossmatch. Most hospitals, including ours, have pathways or guidelines that lay out which of these preparations should be made at the time a patient is admitted to labor and delivery. These are often based on risk factors for hemorrhage but do not take into account the probability that transfusion will be needed. The cost-effectiveness of performing a type and screen or routine crossmatch on patients admitted for delivery has been questioned. Several studies have shown that the chance of transfusions in individuals giving birth is very low. In terms of the need for routine blood preparation, the need for urgent transfusion is most relevant. This has not been included in studies of transfusion rates. ObjectiveThe purpose of this study was to quantify the relative importance of risk factors present on admission for needing a blood transfusion and to develop a formula to define each individual's risk. This could then be used to decide an appropriate level of initial blood preparation for patients at different risk levels. Study DesignRisk factors for hemorrhage and the level of transfusion preparation were extracted from the medical records of a cohort of 89,881 patients delivering in an 18-hospital healthcare system over 40 months. We tabulated the number who required at least one RBC transfusion and the number needing an urgent transfusion-defined as receiving blood during labor or within 4 hours after delivery. Odds ratios for requiring a transfusion were calculated for each risk factor. We then calculated the probability of needing a transfusion for each patient based on their risk factor profile. ResultsA total of 643 patients had any transfusion during their hospitalization (0.72% of deliveries), and 311 had an urgent transfusion (0.35% of deliveries). The calculated probability of needing a transfusion was less than 1% in 87.8% of patients and was greater than 5% in 1.2% of patients. The chance of needing a transfusion was highest for placenta accreta spectrum, admission Hgb <8.0, and placenta previa. A second tier of risk factors included abruption, bleeding with no specific diagnosis, and Hgb between 8.0 and 10.0. ConclusionIn our cohort, very few patients received a transfusion. Applying a formula derived from patient-specific risk factors, we found that almost all patients have a very low probability of needing a transfusion, especially an urgent transfusion. Based on these results, we suggest that a hold clot be used except for the highest-risk patients or in settings with barriers to procuring blood in the rare case of urgent transfusion need. Making this change would greatly reduce hospital blood bank charges.

Automation of Copper-Mediated 18F-Fluorination of Aryl Pinacol Boronates Using 4-Dimethylaminopyridinium Triflate.

Currently, the copper-mediated radiofluorination of aryl pinacol boronates (arylBPin) using the commercially available, air-stable Cu(OTf)2Py4 catalyst is one of the most efficient synthesis approaches, greatly facilitating access to a range of radiotracers, including drug-like molecules with nonactivated aryl scaffolds. Further adjustment of this methodology, in particular, the [18F]fluoride recovery step for the routine preparation of radiotracers, has been the focus of recent research. In our recent study, an organic solution of 4-dimethylaminopyridinium trifluoromethanesulfonate (DMAPOTf) was found to be an efficient PTC for eluting radionuclides retained on the weak anion exchange cartridge, Oasis WAX 1cc, employing the inverse sorption-elution protocol. Notably, the following Cu-mediated radiofluorination of arylBPin precursors in the presence of the Cu(OTf)2(Py)4 catalyst can be performed with high efficiency in the same solvent, bypassing not only the conventional azeotropic drying procedure but any solvent replacement. In the current study, we aimed to translate this methodology, originally developed for remote-controlled operation with manual interventions, into the automated synthesis module on the TRACERlab automation platform. The adjustment of the reagent amounts and solvents allowed for high efficiency in the radiofluorination of a series of model arylBPin substrates on the TRACERlab FXFE Pro synthesis module, which was adapted for nucleophilic radiofluorinations. The practical applicability of the developed radiofluorination approach with DMAPOTf elution was demonstrated in the automated synthesis of 6-L-[18F]FDOPA. The radiotracer was obtained with an activity yield (AY; isolated, not decay-corrected) of 5.2 ± 0.5% (n = 3), with a synthesis time of ca. 70 min on the TRACERlab FX N Pro automation platform. The obtained AY was comparable with one reported by others (6 ± 1%) using the same boronate precursor, while a slightly higher AY of 6-L-[18F]FDOPA (14.5 ± 0.5%) was achieved in our previous work using commercially available Bu4NOTf as the PTC.

Auricular point acupressure for managing postoperative pain and reducing anxiety in patients with perianal abscesses

ObjectiveThe objective of this study is to assess the efficacy of auricular point acupressure in relieving postoperative pain and reducing anxiety among patients with perianal abscesses. MethodsWe included 61 patients with perianal abscesses who were admitted to the Nantong First People's Hospital between July 2019 and June 2020 and were scheduled to undergo one-stage radical surgery. We divided them into the treatment group (n = 31), where patients were administered preoperative auricular acupressure targeting the bilateral Shenmen, subcortical, and other points. They were instructed to apply pressure five to six times per day, each time for about 3–5 min. Patients in the control group (n = 30) received routine preoperative preparation. The treatment duration for both groups was one week. We compared the two groups using the pain visual analog scale (VAS) scores, the use of additional postoperative analgesics, and scores on the Hamilton anxiety and depression scales pre- and post-surgery at 6 h, 24 h, 48 h, 72 h, and 1 week after surgery, as well as at the time of the first bowel movement. ResultsPatients in the treatment group reported lower VAS scores than those of the control group at 48 h, 72 h, 1 week, and at the first defecation post-surgery, and the differences were statistically significant (all P < 0.05). Additional postoperative analgesics were used in seven patients in the treatment group (22.58 %) and in 10 patients in the control group (33.33 %). The difference between the two groups was not statistically significant (χ2 = 0.88, P = 0.35). Postoperative scores for the Hamilton Anxiety Rating Scale (HAM-A) and the Hamilton Depression Rating Scale (HAM-D) in the treatment group were significantly lower than those in the control group (P < 0.05). ConclusionThe results of this study demonstrated that auricular point acupressure was effective in alleviating postoperative pain in patients with perianal abscesses and simultaneously reduced their postoperative psychological stress reactions. This dual effect provided both pain relief and a reduction of anxiety with fewer adverse reactions, making it a safe and effective treatment option.

Scanning Electron Microscopy.

Scanning electron microscopy (SEM) remains distinct in its ability to allow topographical visualization of structures. Key elements to consider for successful examination of biological specimens include appropriate preparative and imaging techniques. Chemical processing induces structural artifacts during specimen preparation, and several factors need to be considered when selecting fixation protocols to reduce these effects while retaining structures of interest. Particular care for proper dehydration of specimens is essential to minimize shrinkage and is necessary for placement under the high-vacuum environment required for routine operation of standard SEMs. Choice of substrate for mounting and coating specimens can reduce artifacts known as charging, and a basic understanding of microscope settings can optimize parameters to achieve desired results. This article describes fundamental techniques and tips for routine specimen preparation for a variety of biological specimens, preservation of labile or fragile structures, immune-labeling strategies, and microscope imaging parameters for optimal examination by SEM. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Chemical preparative techniques for preservation of biological specimens for examination by SEM Alternate Protocol 1: Practical considerations for the preparation of soft tissues Alternate Protocol 2: Removal of debris from the exoskeleton of invertebrates Alternate Protocol 3: Fixation of colonies grown on agar plates Alternate Protocol 4: Stabilization of polysaccharide structures with alcian blue and lysine Alternate Protocol 5: Preparation of non-adherent particulates in solution for SEM Support Protocol 1: Application of thin layer of adhesive on substrate to improve adherence Support Protocol 2: Poly-L-lysine coating specimen substrates for improved adherence Support Protocol 3: Microwave processing of biological specimens for examination by SEM Basic Protocol 2: Critical point drying of specimens Alternate Protocol 6: Chemical alternative to critical point drying Basic Protocol 3: Sputter coating Alternate Protocol 7: Improved bulk conductivity through "OTOTO" Basic Protocol 4: Immune-labeling strategies Alternate Protocol 8: Immune-labeling internal antigens with small gold probes Alternate protocol 9: Quantum dot or fluoronanogold preparations for correlative techniques Basic Protocol 5: Exposure of internal structures by mechanical fracturing Basic Protocol 6: Exposure of internal structures of tissues by fracturing with liquid nitrogen Basic Protocol 7: Anaglyph production from stereo pairs to produce 3D images.

Reliable Method for Estimating Nerve Fiber Density in Epidermis Using Routine Histopathologic Tissue Preparation: A Promising Diagnostic Tool for Small Fiber Neuropathy.

Practical yet reliable diagnostic tools for small-fiber neuropathy are needed. We aimed to establish a histopathologic protocol for estimating intraepidermal nerve fiber density (eIENFD) on formalin-fixed, paraffin-embedded tissue (FFPE), evaluate its reliability through intraobserver and interobserver analyses, and provide normative reference values for clinical use. Sixty-eight healthy participants underwent nerve conduction studies and quantitative sensory testing. Skin biopsies from the distal and proximal leg were taken and processed using routine immunohistochemistry (anti-PGP9.5 antibodies) on thin 5 µm sections. eIENFD was assessed with a modified counting protocol. Interobserver and intraobserver reliabilities were excellent (ICC=0.9). eIENFD was higher in females than males (fibers/mm, 14.3±4.4 vs. 11.6±5.8, P <0.05), decreased with age ( r s =-0.47, P <0.001), and was higher proximally than distally (15.0±5.5 vs. 13.0±5.3, P =0.002). Quantile regression equations for the fifth percentile of distal and proximal eIENFD were presented: 13.125-0.161×age (y)-0.932×sex (male=1; female=0) and 17.204-0.192×age (y)-3.313×sex (male=1; female=0), respectively. This study introduces a reliable and reproducible method for estimating epidermal nerve fiber density through immunostaining on 5-µm thin FFPE tissue samples. Normative data on eIENFD is provided. Regression equations help identify abnormal decreases in small nerve fiber density.

Solar Image Quality Assessment: A Proof of Concept Using Variance of Laplacian Method and its Application to Optical Atmospheric Condition Monitoring

Here we present a proof of concept for the application of the Variance of Laplacian (VL) method in quantifying the sharpness of optical solar images. We conducted a comprehensive study using over 65,000 individual solar images acquired on more than 160 days. Each image underwent processing using a VL image processing algorithm, which assigns a “score” based on the sharpness of the solar disk’s edges. We studied the scores obtained from images acquired at different conditions. Our findings demonstrate that the sharpness of the images exhibits daily trends that are closely linked to the altitude of the Sun at the observation site. We observed a significant degradation in image quality only below a certain altitude threshold. Furthermore, we compared airmass formulae from the literature with our sharpness observations and concluded that the degradation could be modeled as an Image Sharpness Function (ISF), which exhibits similarities to airmass variations. In addition to assessing image quality, our method has the potential to evaluate the optical atmospheric conditions during daytime observations. Moreover, this technique can be easily and cost-effectively applied to archival or real-time images of other celestial bodies, such as the Moon, bright planets and defocused stars. Given that ISF is unique to each location and sensitive to sky conditions, the development of an ISF is not only beneficial for routine observation preparation but also essential for long-term site monitoring.

Formulation of patient dose of [177Lu]Lu-Trastuzumab using in-house developed freeze-dried kit: A path forward for clinical translation.

Trastuzumab is a US-FDA-approved humanized monoclonal antibody used for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. The aim of the present work is to optimize a freeze-dried formulation of DOTA-Trastuzumab conjugate for the preparation of patient doses of [177Lu]Lu-Trastuzumab for radioimmunotherapy of breast cancer. The formulation of [177Lu]Lu-Trastuzumab usually takes a long time, and thus, such a process is not suitable for the routine preparation of this agent in hospital radiopharmacies. To circumvent this, a pre-synthesized DOTA-Trastuzumab conjugate as a freeze-dried formulation is proposed. In the present work, DOTA-Trastuzumab conjugate was subjected to a freeze-drying process after the addition of optimized amounts of radioprotectant and cryoprotectant. [177Lu]Lu-DOTA-Trastuzumab was prepared by incubating the lyophilized powder of the kit vial with medium-specific activity 177LuCl3. The final radiochemical purity of [177Lu]Lu-DOTA-Trastuzumab, prepared using freeze-dried kit, was determined to be >95%. To ascertain the reproducibility of the procedure, six consecutive batches of the freeze-dried formulation were prepared, radiolabeled, and evaluated by carrying out both in vitro and ex vivo studies. The consistency of the results of all the six consecutive batches confirmed the robustness and utility of the in-house optimized freeze-dried formulation for the preparation of patient doses of [177Lu]Lu-Trastuzumab at hospital radiopharmacies.

Non-Contact Electric Field May Induced Higher CD4, CD8, Caspase-8, and Caspase-9 Protein Expression in Breast Tumor Tissue of Rats (Rattus norvegicus Berkenhout, 1769)

Non-contact electric field therapy has been studied as one of less invasive and safe alternative method in cancer therapy. Some studies reported that non-contact electric field therapy with low intensity (50 - 60 V/m) and medium frequency (150 kHz) could slower the rat’s breast tumor growth and did not cause significant damage on the rat's kidney and liver. However, further study needed to evaluate the potency of non-contact electric field to be developed into effective cancer therapy. Thus, we investigated the immune response of non-contact electric field therapy through the detection of CD4 and CD8 protein expression and the mechanism of apoptosis through the detection of caspase-8 and caspase-9 proteins on breast tumor tissue of rats. Twenty four rats were divided into 4 groups: 1. non-induction - non-therapy (NINT), 2. non-induction - therapy (NIT), 3. induction - non-therapy (INT), and 4. induction - therapy (IT). DMBA (7,12-dimethylbenz(α)anthracene) 20 mg/kg body weight was used to induced breast tumor formation. Rats with breast nodules that had reached 1 cm in size were exposed to an ECCT device with 150 kHz and 50 - 60 V/m electric fields. Further, the breast tissues were collected for routine histological and immunohistochemistry preparation for CD4, CD8, caspase 8, as well as caspase 9 detection. The data were statistically analyzed using Mann-Whitney U-Test method, with a significance level of p &lt; 0.05 using the SPSS 16.0 version. The scoring results were compared between the INT and IT groups. Our results showed that non-contact electric field therapy could suppress breast tumor growth and improved its histological structure. Interestingly, the breast tissue of IT group qualitatively had slightly more necrotic and apoptotic cells than that of INT group. Moreover, the IT group showed by higher CD4 and CD8 as well as higher caspase 8 and caspase 9 expression. Collecting all the data together, we concluded that non-contact electric field therapy potent to improve histological structure of breast tumor.

Low-Temperature X-ray Microanalysis Sheds New Light on Mineral Nutrition Aspects of Insect Leaf Galling.

Manipulation of host plant physiology by leaf-galling insects is a multifaceted process. Among fundamental knowledge gaps surrounding this scientifically intriguing phenomenon is the appropriation of plant mineral nutrients and moisture for galling advantage. Small, soluble mineral ions and watery cell contents in dense gall tissues risk disruption during routine sample preparations. In this study, an X-ray microanalysis was applied to investigate gall mineral nutrition. Morphologically diverse leaf galls were sampled from three Australian rainforest tree species. Using cryo-analytical scanning electron microscopy, real-time X-ray analytical maps of cellular mineral nutrients and water were integrated with anatomical images of gall and leaf cross-sectional surfaces. A comparison of host-leaf and gall anatomies bore direct evidence of drastic changes to leaf cells through the galling process. Distinct "wet" and "dry" regions within galls were anatomically and/or chemically differentiated, suggesting specific functionality. "Wet" regions comprising hydrated cells including soft gall-cavity linings where larvae are known to feed contained soluble plant mineral nutrients, while C-rich "dry" tissues largely devoid of mineral nutrients likely contribute structural support. Mapping immobile nutrients such as Mn may provide a means of "matching" specific gall cell types to those in ungalled host-leaf tissues. The findings here provided otherwise inaccessible insights into leaf-gall mineral nutrition.

#8 : The Effect of IVF-ET Electro-Ultrasound Therapy on the Outcome of Frozen Embryo Transfer in Patients with Thin Endometrium

Background and Aims: This study are to investigate the clinical indicators of the infertile population of IVF-ET thin endometrium patients after electro-ultrasound treatment, record the observational data and analyze the clinical effectiveness of this treatment method. Method: Patients undergoing IVF-ET freeze-thaw embryo transfer from March 2022 to November 2022 were screened, and those who met the entry criteria were randomly grouped by random number table method. Treatment group (n=32): patients who received electro-ultrasound therapy; patients treated with electro-ultrasound (MLD-C7000) once a day for 30 minutes for 7 days for 1-3 sessions in the context of conventional FET preparation of the endothelium. Control group (n=69): Routine FET preparation of the endometrium without. Results: There were no significant differences in basic data (P &gt; 0.05). The endometrial thickness on the day of conversion 7.75±2.00 mm was significantly higher in the treatment group than the endometrial thickness on the day of conversion 6.39±0.67 mm in the control group (P&lt;0.05). The biochemical pregnancy rate and clinical pregnancy rate in the treatment group were higher than those in the control group, but the differences were not statistically significant (P &gt; 0.05). Conclusion: In IVF-ET patients with thin endometrium, electro-ultrasound therapy device can effectively improve the endometrial thickness of patients with a trend of beneficial effects on clinical outcomes and can be one of the methods to improve the success rate in patients with thin endometrium. However, further increase in sample size is needed in the future to improve the accuracy of the results.

Evaluation of the efficacy of the Lentulo spiral filler operated at four different speeds and with two different techniques in cadaveric canine teeth of dogs.

This study evaluated the effect of filling technique and rotational speed on the efficacy of sealer cement placement using the Lentulo spiral filler. Cadaveric maxillary and mandibular canine teeth (n = 74) from age and breed matched fresh-frozen adult canine cadaver heads were utilized. Following routine mechano-chemical preparation, teeth were randomly divided into 8 treatment groups with varying rotational speeds [250-2,000 revolutions per minute (RPM)] and fill techniques (backfill technique versus pumping technique). The quality of the sealer cement fill was evaluated radiographically before and after master gutta percha cone placement. Percentage of voids present in the apical, midbody, and coronal portions of the tooth were subjectively scored as: no voids present, voids present in less than 25% of the area, voids present in 25-50% of the area, voids present in greater than 50% of the area. The apex was also scored as underfilled, adequately filled, or overfilled. Operating the Lentulo spiral filler at 2,000 RPM resulted in the best quality fill regardless of filling technique. The pumping technique with placement of the master gutta percha cone had a higher probability of success as compared to the backfill technique, but this finding lacked significance. Regardless of speed or technique, the apical region had the highest quality of fill. The addition of the master gutta percha cone improved the quality of fill. Therefore, we recommend using the Lentulo spiral filler at higher speeds with a pumping technique (followed by addition of a master gutta percha cone) to improve the quality of epoxy resin-based sealer cement placement.

Letrozole-stimulated endometrial preparation protocol is a superior alternative to hormone replacement treatment for frozen embryo transfer in women with polycystic ovary syndrome, a cohort study

BackgroundThe current routine endometrial preparation protocol for women with polycystic ovary syndrome (PCOS) is hormone replacement treatment (HRT). Letrozole is rarely used in frozen embryo cycles. Evidence confirming whether letrozole-stimulated (LS) protocol is suitable for frozen embryo transfer in patients with PCOS and for whom is suitable remains lacking.MethodsThis was a retrospective cohort study involving all frozen embryo transfer cycles with LS and HRT for PCOS during the period from Jan 2019 to December 2020 at a tertiary care center. Multivariate Logistic regression was used to analyze the differences in clinical pregnancy rate, live birth rate, miscarriage rate, the incidence of other pregnancy and obstetric outcomes between LS and HRT protocols after adjusting for possible confounding factors. Subgroup analysis was used to explore the population for which LS protocol was suitable.ResultsThe results of multivariate logistic regression showed that LS was significantly associated with a higher clinical pregnancy rate (70.9% vs. 64.4%;aOR:1.41, 95%CI: 1.18,1.68), live birth rate (60.5% vs. 51.4% aOR:1.49, 95%CI: 1.27,1.76), and a lower risk of miscarriage (14.7% vs. 20.1% aOR: 0.68, 95%CI: 0.53,0.89), hypertensive disorders of pregnancy (6.7% vs. 8.9% aOR: 0.63, 95%CI: 0.42,0.95), and gestational diabetes mellitus (16.7% vs. 20.7% aOR:0.71, 95%CI: 0.53,0.93) than HRT. There were no significant differences in other outcomes such as preterm birth, cesarean delivery, small for gestational age, or large for gestational age between the two endometrial preparation protocols. Subgroup analysis showed that LS had higher live birth rates than HRT in most of the subgroups; in the three subgroups of maternal age ≥ 35 years, menstrual cycle < 35 days, and no insulin resistance, the live birth rates of the two endometrial preparation protocols were comparable.ConclusionsLS protocol could improve the live birth rate and reduce the incidence of miscarriage, hypertensive disorders of pregnancy and gestational diabetes mellitus in patients with PCOS. LS protocol is suitable for all types of patients with PCOS. LS should be considered the preferred endometrial preparation protocol for women with PCOS.

Letrozole use in vitrified single-blastocyst transfer cycles is associated with lower risk of large for gestational age infants in patients with polycystic ovary syndrome.

To evaluate the obstetric and perinatal outcomes of three routine endometrial preparation protocols in women with PCOS who underwent frozen embryo transfer (FET). This was a retrospective study in women with PCOS who underwent FET in an academic reproductive medical center. A total of 2710 cycles were enrolled and classified into three groups according to different endometrial preparation protocols; human menopausal gonadotropin (HMG), letrozole + HMG, or hormone replacement therapy (HRT). The stimulation groups had reduced risks of hypertensive disorders of pregnancy (HDP), large for gestational age (LGA) infants, and cesarean delivery than the HRT group. After adjustment for different confounder combinations in the two models, the frequencies of LGA and HDP in the letrozole + HMG group and the HMG group were still significantly lower than those in the HRT group. The letrozole + HMG group exhibited a reduced risk of LGA than HMG group after adjustment of confounders. A trend toward risk reductions in HDP and LGA was observe in turns of HRT, HMG, and letrozole + HMG groups, and the trends were statistically significant (Ptrend = 0.031 and 0.001). In patients with PCOS, ovarian stimulation protocols for endometrial preparation are associated with reduced risks of HDP and LGA compared to HRT cycles. The use of letrozole could further reduce risk of LGA compared to HMG only protocol. We propose that ovarian stimulation protocols can be used widely for endometrial preparation in FET cycles in women with PCOS, especially with the use of letrozole.

Expert consensus on routine preparation of endoscopic submucosal dissection/endoscopic mucosal resection specimens

Expert consensus on routine preparation of endoscopic submucosal dissection/endoscopic mucosal resection specimens

Effects of Sample Dilution on Nuclear Magnetic Resonance-Derived Metabolic Profiles of Human Urine.

Traditionally, a relatively big urine volume (e.g., 500 μL) is used in nuclear magnetic resonance (NMR)-based human metabolomics, which is not feasible for studies with limited/precious samples. Although urine may be diluted before conventional high-throughput metabolomics analysis, the comprehensive effect of urine dilution on metabolic profiles is unknown. Here, for the first time, we systematically investigated the effect of urine dilution on 1H NMR metabolic profiles, by evaluating signal detectability, integration, signal-to-noise ratio (SNR), chemical shift (δ) and its variation, and signal overlapping of 47 metabolites in 10 volunteers. We observed significant linear changes along with increased dilution, including decreased integration and SNR, altered δ, decreased intersample variation of δ, and increased separation between overlapped signals, e.g., lactate and threonine, β-d-glucose and an unassigned signal, and histidine and 3-methylhistidine. We further tested the 40% dilution level (i.e., employing 300 μL urine) in an epidemiological study containing 1018 pregnant women from the Tongji-Shuangliu Birth Cohort, showing acceptable detectability and chemical shift variability for most of the 47 metabolites profiled. It indicated that mild (e.g., 40%) dilution of human urine can largely preserve the high-abundance metabolites profiled, reduce intersample chemical shift variations, and increase separations of overlapped signals, which is an improvement of routine sample preparation methods in NMR-based metabolomics and is applicable for studies with limited urine volumes, including large-scale epidemiological studies.

Hyperbaric oxygen therapy: a possible choice for patients with resistant thin endometrium during frozen embryo transfer treatments

BackgroundThin endometrium is considered suboptimal for embryo implantation, leading to compromised pregnancy rates without effective therapies. While some studies have reported promoted endometrial growth after a period of hyperbaric oxygen therapy (HBOT) in patients with intrauterine adhesion, there have been no reports in patients with resistant thin endometrium. The purpose of this study was to investigate the impact of HBOT on endometrium growth and pregnancy outcomes in patients with resistant thin endometrium during frozen embryo transfer (FET) treatments.MethodsThis prospective pre-post cohort study was conducted at a university-affiliated assisted reproductive medical center between October 2021 and December 2022. Patients who had experienced at least one canceled transfer cycle due to a thin endometrium(< 7 mm) on the endometrium transformation day, despite the use of standard therapies as well as adjuvant therapies, were enrolled in the study. Patients were assigned voluntarily to either the HBOT group or the concurrent control group. The HBOT group received daily HBOT for at least 10 days during the proliferative phase, in addition to the routine endometrium preparation methods and the concurrent control group underwent cycles without HBOT. Propensity score matching (PSM) was used to ensure comparability between the groups. Both self-control and case-control comparisons were conducted. The primary outcome measured was endometrial thickness (ET) on the day of endometrium transformation. Secondary outcomes included intrauterine pregnancy rate (IPR), embryo implantation rate (IR), miscarriage rate, and others.ResultsPatients in the HBOT group demonstrated a significantly thicker endometrial thickness on the day of endometrium transformation after undergoing therapy (5.76 ± 1.66 vs. 6.57 ± 1.23, P = 0.002). This improvement was accompanied by a decreased rate of cycle cancellations. Baseline parameters and endometrial thickness were comparable between the HBOT group and the concurrent control group during the cycle. The IPR was similar in patients who received cleavage-stage embryos (0.0% vs. 6.7%, P = 1.00), but significantly higher in patients in the HBOT group who received blastocysts (53.8% vs. 18.2%, P = 0.017).ConclusionsA period of HBOT prior to endometrium transformation contributes to increased endometrial thickness and facilitates blastocyst implantation in patients with resistant thin endometrium during FET treatments.Trial registrationThe trial was registered on the Chinese Clinical Trial Registry (registration no. ChiCTR2300072831, retrospectively registered).

Coordination chemistry applied to anti-doping analysis: Cobalt quantification as its diethyldithiocarbamate complex by liquid chromatography coupled to high resolution tandem mass spectrometry.

Cobalt was included on the World Anti-Doping Agency Prohibited List in 2015 due to its effect on stimulus of erythropoiesis via stabilization of hypoxia-inducible factor. Although it has proven benefits for performance enhancement, the unavailability of inductively coupled plasma-mass spectrometry on routine of the accredited laboratories is a factor that reduces its applicability in anti-doping analysis. Therefore, an analytical method for quantification of urinary cobalt as its diethyldithiocarbamate complex by liquid chromatography coupled with high-resolution tandem mass spectrometry was developed and validated. Palladium was proposed as internal standard and rhodium as a complexation control. A microwave-assisted acid digestion of the urine samples was essential, not only to eliminate the matrix effect but mainly to avoid the non-specific bond of cobalt to endogenous molecules. A linear method was obtained over the studied range from a negative urine control to a spiked concentration of 25 ng/mL, with an estimated limit of quantification of 2.5ng/mL, and an adequate combined standard uncertainty of 11.4%. Considering that all reagents are commercially available, the proposed strategy is feasible to be included on routine sample preparation. Monitoring urinary cobalt concentrations globally opens the perspective to support the anti-doping system to define a suitable threshold value and to understand its potential misuse by athletes seeking for performance improvement.

On a Novel Approach to Correcting Temperature Dependencies in Magnetic Observatory Data

High-quality geomagnetic measurements are widely used in both fundamental research of the magnetic field and numerous industrial applications. However, vector data measured by fluxgate sensors show a dependency on temperature due to sensitive coil core material and components of the sensor electronics. Here, we propose a new method for detecting and eliminating temperature dependence in magnetic observatory data. The method is designed to correct temperature drifts in variation vector magnetometer measurements when preparing quasi-definitive data according to an INTERMAGNET standard. A special feature of the method is the semi-automatic adjustment of localization intervals for temperature correction, which prevents boundary jumps and discontinuities in the course of sequential data processing over long intervals. The conservative nature of the approach implies the minimization of the original data amount subjected to correction. The described method is successfully applied in the routine monthly preparation of quasi-definitive data of the Saint Petersburg Observatory (IAGA-code SPG) and can be efficiently introduced at other magnetic observatories worldwide.