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BACKGROUND Cortical lesions are common in multiple sclerosis (MS). T2*-weighted (T2*w) imaging at 7 T is relatively sensitive for cortical lesions, but quality is often compromised by motion and main magnetic field (B0) fluctuations. PURPOSE The aim of this study was to determine whether motion and B0 correction with a navigator-guided gradient-recalled echo sequence can improve cortical lesion detection in T2*w magnetic resonance imaging. MATERIALS AND METHODS In this prospective study, a gradient-recalled echo sequence incorporating a navigator allowing for motion and B0 field correction was applied to collect T2*w images at 7 T from adults with MS between August 2019 and March 2020. T2*-weighted images were acquired in 1 to 3 partially overlapping scans per individual and were reconstructed using global average B0 correction ("uncorrected") or motion correction and spatially linear B0 correction ("corrected"). Image quality rating and manual segmentation of cortical lesions were performed on uncorrected and corrected images. Lesions seen on a single scan were retrospectively evaluated on the complementary scan. The association of cortical lesions with clinical disability was assessed. Mixed models were used to determine the effect of correction on lesion detection as well as on the relationship between disability and lesion count. RESULTS A total of 22 T2*w scans were performed on 11 adults with MS (mean [SD] age, 49 [11] years; 8 women). Quality improved for 20 of 22 scans (91%) after correction. A total of 69 cortical lesions were identified on uncorrected images (median per scan, 2; range, 0-11) versus 148 on corrected images (median per scan, 4.5; range, 0-25; rate ratio [RR], 2.1; P < 0.0001). For low-quality uncorrected scans with moderate to severe motion artifact (18/22, 82%), there was an improvement in cortical lesion detection with correction (RR, 2.5; P < 0.0001), whereas there was no significant change in cortical lesion detection for high-quality scans (RR, 1.3; P = 0.43). CONCLUSIONS Navigator-guided motion and B0 correction substantially improves the overall image quality of T2*w magnetic resonance imaging at 7 T and increases its sensitivity for cortical lesions.

Purposes To develop and evaluate a boundary informed electrical properties tomography (BIEPT) technique for high-resolution imaging of tumor electrical properties (EPs) heterogeneity on a rodent tumor xenograft model. Methods Tumor EP distributions were inferred from a reference area external to the tumor, as well as internal EP spatial variations derived from a plurality of relative transmit B1 measurements at 7T. Edge sparsity constraint was enforced to enhance numerical stability. Phantom experiments were performed to determine the imaging accuracy and sensitivity for structures of various EP values, as well as geometrical sizes down to 1.5 mm. Numerical simulation of a realistic rodent model was used to quantify the algorithm performance in the presence of noise. Eleven athymic rats with human breast cancer xenograft were imaged in vivo, and representative pathological samples were acquired for comparison. Results Reconstructed EPs of the phantoms correspond well to the ground truth acquired from dielectric probe measurements, with the smallest structure reliably detectable being 3 mm. EPs heterogeneity inside a tumor is successfully retrieved in both simulated and experimental cases. In vivo tumor imaging results demonstrate similar local features and spatial patterns to anatomical MRI and pathological slides. The imaged conductivity of necrotic tissue is higher than that of viable tissues, which agrees with our expectation. Conclusion BIEPT enables robust detection of tumor EPs heterogeneity with high accuracy and sensitivity to small structures. The retrieved quantitative EPs reflect tumor pathological features (e.g., necrosis). These results provide strong rationale to further expand BIEPT studies toward pathological conditions where EPs may yield valuable, non-invasive biomarkers.

Purpose To identify and characterize the sources of B0 field changes due to head motion, to reduce motion sensitivity in human brain MRI. Methods B0 fields were measured in 5 healthy human volunteers at various head poses. After measurement of the total field, the field originating from the subject was calculated by subtracting the external field generated by the magnet and shims. A subject-specific susceptibility model was created to quantify the contribution of the head and torso. The spatial complexity of the field changes was analyzed using spherical harmonic expansion. Results Minor head pose changes can cause substantial and spatially complex field changes in the brain. For rotations and translations of approximately 5 o and 5 mm, respectively, at 7 T, the field change that is associated with the subject's magnetization generates a standard deviation (SD) of about 10 Hz over the brain. The stationary torso contributes to this subject-associated field change significantly with a SD of about 5 Hz. The subject-associated change leads to image-corrupting phase errors in multi-shot T 2 * -weighted acquisitions. Conclusion The B0 field changes arising from head motion are problematic for multishot T 2 * -weighted imaging. Characterization of the underlying sources provides new insights into mitigation strategies, which may benefit from individualized predictive field models in addition to real-time field monitoring and correction strategies.

Objective: The purpose is to provide a comprehensive review of the electrical properties tomography (EPT) technique, which was introduced to image the electrical properties (EPs) of tissue noninvasively by exploiting the measured B1 field data of MRI. Methods: We reviewed the principle of EPT, reconstruction methods, biomedical applications such as tumor imaging, and existing challenges. As a key application of EPT, the estimation of specific absorption rate (SAR) due to MRI was discussed in the background of elevated risk of tissue heating at high field. Results and Conclusion: Since the originally proposed local, homogeneous Helmholtz equation-based reconstruction algorithm, advanced EPT algorithms have emerged to address the challenges of EPT, including reconstruction error near tissue boundaries, noise sensitivity, inaccurate B 1 phase estimation, and elimination of the unmeasurable Bz component, along with demonstrations of in vivo experiments. EPT techniques have been applied to investigate EPs of both healthy and pathological tissues in vivo and factors contributing to various EP value, including sodium, water content, etc. More studies are anticipated to consolidate the current findings. EPT-based subject-specific SAR estimation has led to in vivo demonstration of its feasibility and prediction of temperature increase of phantom during MRI scans merely using measured B 1 data. Significance: EPT has the advantage of high resolution and practical feasibility in a clinical setup for imaging the biomedically interesting EPs of tissue in the radiofrequency range. EPT-based SAR estimation is another promising topic for predicting tissue heating of individual subjects during a specific MRI scan.

Long non-coding RNA (lncRNA) ASB16 antisense RNA 1 (ASB16-AS1) is recognized as an oncogene in several cancer types, but its relation to GC is unknown. Tripartite motif containing 37 (TRIM37) has been proven to accelerate the development of gastric cancer (GC), whereas the molecular mechanism assisted ASB16-AS1 and TRIM37 in regulating GC progression remains unclear. Differentially expressed lncRNAs in GC samples were analyzed based on Gene Expression Omnibus (GEO) data. CCK-8 and colony formation assays were applied to determine the proliferative ability of GC cells. Stem cell-like phenotype of GC cells was assessed by sphere formation assay and flow cytometry analysis. Luciferase reporter assay, RNA immunoprecipitation (RIP), pulldown, and co-immunoprecipitation (Co-IP) were performed to verify the interplay of RNA molecules. ASB16-AS1 was upregulated in GC samples according to GEO data and qRT-PCR analysis. ASB16-AS1 strengthened the proliferative ability and stem cell-like characteristics in GC cells. More importantly, ASB16-AS1 encouraged GC cell growth in vivo. Mechanistically, ASB16-AS1 strengthened TRIM37 expression by sequestering miR-3918 and miR-4676-3p. ASB16-AS1 activated NF-kappa B (NF-κB) pathway by cooperating with ATM serine/threonine kinase (ATM) to induce TRIM37 phosphorylation. In summary, ASB16-AS1 exerted oncogenic functions in GC through modulating TRIM37 expression at both mRNA and protein levels.

T(2)*-weighted gradient echo (GRE) MRI at high field is uniquely sensitive to the magnetic properties of tissue and allows the study of brain and vascular anatomy at high spatial resolution. However, it is also sensitive to B(0) field changes induced by head motion and physiological processes such as the respiratory cycle. Conventional motion correction techniques do not take these field changes into account, and consequently do not fully recover image quality in T(2)*-weighted MRI. Here, a novel approach was developed to address this by monitoring the B(0) field with a volumetric EPI phase navigator. The navigator was acquired at a shorter echo time than that of the (higher resolution) T(2)*-weighted GRE imaging data and accelerated with parallel imaging for high temporal resolution. At 4 mm isotropic spatial resolution and 0.54 s temporal resolution, the accuracy for estimation of rotation and translation was better than 0.2° and 0.1 mm, respectively. The 10% and 90% percentiles of B(0) measurement error using the navigator were −1.8 and 1.5 Hz at 7 T, respectively. A fast retrospective reconstruction algorithm correcting for both motion and nonlinear B(0) changes was also developed. The navigator and reconstruction algorithm were evaluated in correcting motion-corrupted high-resolution T(2)*-weighted GRE MRI on healthy human subjects at 7 T. Excellent image quality was demonstrated with the proposed correction method.

MR-based electrical properties tomography converts the MRI transmit/receive RF field measurements to tissue electrical property maps through dedicated reconstruction algorithms. Recent reports showed that despite limitations, electrical properties tomography holds promise for generating additional contrast for tumor detection and patient-specific modeling of tissue-RF field interactions. This review summarizes the available tissue electrical property contrasts and compares them with the capabilities of the most commonly used electrical properties tomography reconstruction method. Future directions and prospects of clinical translation are discussed.

PURPOSE: To identify and characterize the sources of B(0) field changes due to head motion to reduce motion sensitivity in human brain MRI. METHODS: B(0) fields were measured in five healthy human volunteers at various head poses. After measurement of the total field (TF), the field originating from the subject (SF) was calculated by subtracting the external field (EF) generated by the magnet and shims. A subject-specific susceptibility model was created to quantify the contribution of the head and torso. The spatial complexity of the field changes was analyzed using spherical harmonic expansion. RESULTS: Minor head pose changes can cause substantial and spatially complex field changes in the brain. For rotations and translations of about 5° and 5 mm respectively at 7 T, the SF component alone generates a resonance frequency shift over the brain with a standard deviation of about 10 Hz. The stationary torso contributes to the SF significantly with a standard deviation of about 5 Hz. These SF change leads to image-corrupting phase errors in multi-shot T(2)*-weighted acquisitions. CONCLUSION: The B(0) field changes arising from head motion are problematic for multi-shot T(2)*-weighted imaging. Characterization of the underlying sources provides new insights into mitigation strategies, which may benefit from individualized predictive field models in addition to real-time field monitoring and correction strategies.

Frequency-dependent electrical properties (EPs; conductivity and permittivity) of biological tissues provide important diagnostic information (e.g. tumor characterization), and also play an important role in quantifying radiofrequency (RF) coil induced Specific Absorption Rate (SAR) which is a major safety concern in high- and ultrahigh-field Magnetic Resonance Imaging (MRI) applications. Cross-sectional imaging of EPs has been pursued for decades. Recently introduced Electrical Properties Tomography (EPT) approaches utilize the measurable RF magnetic field induced by the RF coil in an MRI system to quantitatively reconstruct the EP distribution in vivo and non-invasively with a spatial resolution of a few millimeters or less. This paper reviews the Electrical Properties Tomography approach from its basic theory in electromagnetism to the state of the art research outcomes. Emphasizing on the imaging reconstruction methods rather than experimentation techniques, we review the developed imaging algorithms, validation results in physical phantoms and biological tissues, as well as their applications in in vivo tumor detection and subject-specific SAR prediction. Challenges for future research are also discussed.

Electrical Property Tomography (EPT) is a recently developed noninvasive technology to image the electrical conductivity and permittivity of biological tissues at Larmor frequency in Magnetic Resonance (MR) scanners. The absolute phase of the complex radio-frequency (RF) magnetic field (B1) is necessary for electrical property calculation. However, due to the lack of practical methods to directly measure the absolute B1 phases, current EPT techniques have been achieved with B1 phase estimation based on certain assumptions on object anatomy, coil structure and/or electromagnetic wave behavior associated with the main magnetic field, limiting EPT from a larger variety of applications. In this study, using a multi-channel transmit/receive coil, the framework of a new general approach for EPT has been introduced, which is independent on the assumptions utilized in previous studies. Using a human head model with realistic geometry, a series of computer simulations at 7T were conducted to evaluate the proposed method under different noise levels. Results showed that the proposed method can be used to reconstruct the conductivity and permittivity images with noticeable accuracy and stability. The feasibility of this approach was further evaluated in a phantom experiment at 7T.

Elevated specific absorption rate (SAR) associated with increased main magnetic field strength remains a major safety concern in ultra-high-field (UHF) magnetic resonance imaging (MRI) applications. The calculation of local SAR requires the knowledge of the electric field induced by radio-frequency (RF) excitation, and the local electrical properties of tissues. Since electric field distribution cannot be directly mapped in conventional MR measurements, SAR estimation is usually performed using numerical model-based electromagnetic simulations which, however, are highly time consuming and cannot account for the specific anatomy and tissue properties of the subject undergoing a scan. In the present study, starting from the measurable RF magnetic fields (B1) in MRI, we conducted a series of mathematical deduction to estimate the local, voxel-wise and subject-specific SAR for each single coil element using a multi-channel transceiver array coil. We first evaluated the feasibility of this approach in numerical simulations including two different human head models. We further conducted experimental study in a physical phantom and in two human subjects at 7T using a multi-channel transceiver head coil. Accuracy of the results is discussed in the context of predicting local SAR in the human brain at UHF MRI using multi-channel RF transmission.

Background Recent advances in next-generation sequencing (NGS) have provided new methods for preimplantation genetic screening (PGS) of human embryos from in vitro fertilization (IVF) cycles. However, there is still limited information about clinical applications of NGS in IVF and PGS (IVF-PGS) treatments. The present study aimed to investigate the effects of NGS screening on clinical pregnancy and implantation outcomes for PGS patients in comparison to array comparative genomic hybridization (aCGH) screening. Methods This study was performed in two phases. Phase I study evaluated the accuracy of NGS for aneuploidy screening in comparison to aCGH. Whole-genome amplification (WGA) products (n = 164) derived from previous IVF-PGS cycles (n = 38) were retrospectively analyzed with NGS. The NGS results were then compared with those of aCGH. Phase II study further compared clinical pregnancy and implantation outcomes between NGS and aCGH for IVF-PGS patients. A total of 172 patients at mean age 35.2 ± 3.5 years were randomized into two groups: 1) NGS (Group A): patients (n = 86) had embryos screened with NGS and 2) aCGH (Group B): patients (n = 86) had embryos screened with aCGH. For both groups, blastocysts were vitrified after trophectoderm biopsy. One to two euploid blastocysts were thawed and transferred to individual patients primarily based on the PGS results. Ongoing pregnancy and implantation rates were compared between the two study groups. Results NGS detected all types of aneuploidies of human blastocysts accurately and provided a 100 % 24-chromosome diagnosis consistency with the highly validated aCGH method. Moreover, NGS screening identified euploid blastocysts for transfer and resulted in similarly high ongoing pregnancy rates for PGS patients compared to aCGH screening (74.7 % vs. 69.2 %, respectively, p >0.05). The observed implantation rates were also comparable between the NGS and aCGH groups (70.5 % vs. 66.2 %, respectively, p >0.05). Conclusions While NGS screening has been recently introduced to assist IVF patients, this is the first randomized clinical study on the efficiency of NGS for preimplantation genetic screening in comparison to aCGH. With the observed high accuracy of 24-chromosome diagnosis and the resulting high ongoing pregnancy and implantation rates, NGS has demonstrated an efficient, robust high-throughput technology for PGS.

Electrical properties tomography (EPT) holds promise for noninvasively mapping at high spatial resolution the electrical conductivity and permittivity of biological tissues in vivo using a magnetic resonance imaging (MRI) scanner. In the present study, we have developed a novel gradient-based EPT approach with greatly improved tissue boundary reconstruction and largely elevated robustness against measurement noise compared to existing techniques. Using a 7 Tesla MRI system, we report, for the first time, high-quality in vivo human brain electrical property images with refined structural details, which can potentially merit clinical diagnosis (such as cancer detection) and high-field MRI applications (quantification of local specific absorption rate) in the future.

Electrical Properties Tomography (EPT) technique utilizes measurable radio frequency (RF) coil induced magnetic fields (B1 fields) in a Magnetic Resonance Imaging (MRI) system to quantitatively reconstruct the local electrical properties (EP) of biological tissues. Information derived from the same data set, e.g., complex numbers of B1 distribution towards electric field calculation, can be used to estimate, on a subject-specific basis, local Specific Absorption Rate (SAR). SAR plays a significant role in RF pulse design for high-field MRI applications, where maximum local tissue heating remains one of the most constraining limits. The purpose of the present work is to investigate the feasibility of such B1-based local SAR estimation, expanding on previously proposed EPT approaches. To this end, B1 calibration was obtained in a gelatin phantom at 7 T with a multi-channel transmit coil, under a particular multi-channel B1-shim setting (B1-shim I). Using this unique set of B1 calibration, local SAR distribution was subsequently predicted for B1-shim I, as well as for another B1-shim setting (B1-shim II), considering a specific set of parameter for a heating MRI protocol consisting of RF pulses plaid at 1% duty cycle. Local SAR results, which could not be directly measured with MRI, were subsequently converted into temperature change which in turn were validated against temperature changes measured by MRI Thermometry based on the proton chemical shift.

It has been shown that Electrical Properties d(EPs) of biological tissues can be derived from MR-based B1 measurement. A strong appeal for these `Electrical Property Tomography' (EPT) methods is to estimate real-time and subject-specific local specific absorption rate (SAR) induced by RF transmission. In order to investigate the feasibility of EPT-based local SAR estimation, following previously proposed EPT protocols, induced local SAR has been firstly estimated under one B1 shim setting for a heating sequence at 7T; whereas with the same acquired B1 information, induced local SAR under a different B1 shim setting has been further predicted. Both of the SAR results have been compared to measured temperature changes using MRI Thermometry based on the proton chemical shift.

Objective: To assess the technique of injecting a single sperm and cytoplasm obtained from tripronucleate zygotes into metaphase II oocytes for the treatment of patients with repeated implantation failure after intracytoplasmic sperm injection or IVF. Design: Clinical study. Setting: Private infertility clinic. Patient(s): Patients with repeated implantation failure after intracytoplasmic sperm injection or IVF. Intervention(s): The metaphase II oocytes of recipients were injected with their husbands' spermatozoa and cytoplasm aspirated from the tripronucleate zygotes of donors. Main Outcome Measure(s): Fertilization after cytoplasm and sperm injection, embryo development, and successful pregnancy. Result(s): In total, 62 metaphase II oocytes from nine recipients were injected. Of the 62 injected oocytes, 3 (5%) degenerated and 43 (69%) had two pronuclei 18 hours after injection. Thirty-nine oocytes with two pronuclei cleaved to the two-cell to six-cell stage after another 24 hours of culture. All cleaved embryos were transferred into the uteruses of recipients. Four clinical pregnancies occurred in four recipients. No abnormal chromosomes were observed after amniocentesis and karyotyping in all pregnancies. Five healthy infants were born. Conclusion(s): Injection of the cytoplasm of tripronucleate zygotes may enhance the clinical pregnancy rate in patients with repeated implantation failure after intracytoplasmic sperm injection or IVF.

Objective: To assess the ultrarapid fluorescence in situ hybridization (FISH) procedure with a 1-minute hybridization time for gender determination. Design: Fluorescence in situ hybridization with direct label fluorescence DNA probes for chromosomes X and Y were tested with the use of different hybridization times and different cell types. Setting: Hospital-based IVF program. Intervention(s): The efficiency of the FISH procedure with different hybridization times was compared with the use of male lymphocytes. The same FISH procedure, but with only 1-minute hybridization, was carried out in human blastomeres, spermatozoa, uncultured amniocytes, male lymphocytes, and female lymphocytes. Main Outcome Measure(s): Percentages of nuclei with positive signals. Result(s): The percentages of nuclei with positive signals in lymphocytes with hybridization times of 1, 3, 4, 10, 30, and 45 minutes were 97%, 97%, 98%, 98%, 98%, and 98%, respectively. The percentages of nuclei with positive signals after FISH with a 1-minute hybridization time in single blastomeres, spermatozoa, amniocytes, male lymphocytes, and female lymphocytes were 94%, 96%, 96%, 98%, and 97%, respectively. Conclusion(s): Chromosomes X and Y of human blastomeres, spermatozoa, uncultured amniocytes, and lymphocytes can be detected rapidly with the use of this ultrarapid FISH procedure with a 1-minute hybridization time.

In order to increase the number of chromosomes examined in each blastomere, we have developed a repeated fluorescent in-situ hybridization (FISH) procedure by which six or more chromosomes can be analysed per blastomere of a human embryo. Three consecutive FISH procedures with directly-labelled fluorescent Vysis DNA probes were carried out for examination of chromosomes X, Y, 11, 13, 18 and 21 in the same blastomeres (n = 126) and lymphocytes (n = 164). Based on the initial number of nuclei, the percentages of nuclear loss and presence of signals were 3 and 92% respectively in blastomeres; 6 and 91% respectively in lymphocytes after the first FISH; 7 and 87% respectively in blastomeres and 10 and 86% respectively in lymphocytes, after the second FISH. These percentages were 13 and 78% respectively in blastomeres and 14 and 81% respectively in lymphocytes after the third FISH. The FISH procedure was repeated successfully in a couple for preimplantation genetic diagnosis of chromosomal aneuploidies in biopsied blastomeres of their embryos in our clinic. In conclusion, it is feasible to carry out repeated FISH procedures in the same blastomeres. Six or more chromosomes of a single blastomere may be examined using this procedure.

The effect of in-vitro culture on the motility and morphology of fresh and frozen-thawed human testicular spermatozoa obtained from obstructive azoospermic patients and on the motility of testicular spermatozoa obtained from non-obstructive azoospermic patients was evaluated. The outcome of intracytoplasmic sperm injection (ICSI) with fresh and frozen-thawed human testicular spermatozoa was studied. The results showed that significant improvement of sperm morphology and motility was observed in culture of fresh (n = 17) and frozen-thawed (n = 15) testicular sperm samples obtained from patients with obstructive azoospermia. The motility of cultured testicular spermatozoa reached a peak at 72 h without the need for special media. In six of 20 samples obtained from patients with non-obstructive azoospermia, improvement of sperm motility was observed. When only non-motile testicular spermatozoa were cultured, they all remained non-motile (n = 9). In patients with obstructive azoospermia, fertilization rates of 80 and 81% were obtained using ICSI with fresh and frozen-thawed testicular spermatozoa respectively. Clinical pregnancies were observed in four out of nine patients with fresh testicular spermatozoa and two out of five patients after using frozen-thawed spermatozoa. When fresh testicular spermatozoa obtained from patients with non-obstructive azoospermia were used for ICSI, the fertilization rate was 68% and two out of seven patients achieved clinical pregnancies. In conclusion, the morphology and motility of fresh and frozen-thawed testicular spermatozoa in patients with obstructive azoospermia can be significantly improved after in-vitro culture. The outcome of in-vitro culture of testicular spermatozoa in patients with non-obstructive azoospermia is unpredictable. In-vitro culture of non-motile testicular spermatozoa is not successful so far. The outcome of ICSI with fresh and with frozen-thawed testicular spermatozoa was similar.

Background Recent advances in time-lapse monitoring in IVF treatment have provided new morphokinetic markers for embryonic competence. However, there is still very limited information about the relationship between morphokinetic parameters, chromosomal compositions and implantation potential. Accordingly, this study aimed at investigating the effects of selecting competent blastocysts for transfer by combining time-lapse monitoring and array CGH testing on pregnancy and implantation outcomes for patients undergoing preimplantation genetic screening (PGS). Methods A total of 1163 metaphase II (MII) oocytes were retrieved from 138 PGS patients at a mean age of 36.6 ± 2.4 years. These sibling MII oocytes were then randomized into two groups after ICSI: 1) Group A, oocytes (n = 582) were cultured in the time-lapse system and 2) Group B, oocytes (n = 581) were cultured in the conventional incubator. For both groups, whole genomic amplification and array CGH testing were performed after trophectoderm biopsy on day 5. One to two euploid blastocysts within the most predictive morphokinetic parameters (Group A) or with the best morphological grade available (Group B) were selected for transfer to individual patients on day 6. Ongoing pregnancy and implantation rates were compared between the two groups. Results There were significant differences in clinical pregnancy rates between Group A and Group B (71.1% vs. 45.9%, respectively, p = 0.037). The observed implantation rate per embryo transfer significantly increased in Group A compared to Group B (66.2% vs. 42.4%, respectively, p = 0.011). Moreover, a significant increase in ongoing pregnancy rates was also observed in Group A compared to Group B (68.9% vs. 40.5%. respectively, p = 0.019). However, there was no significant difference in miscarriage rate between the time-lapse system and the conventional incubator (3.1% vs. 11.8%, respectively, p = 0.273). Conclusions This is the first prospective investigation using sibling oocytes to evaluate the efficiency of selecting competent blastocysts for transfer by combining time-lapse monitoring and array CGH testing for PGS patients. Our data clearly demonstrate that the combination of these two advanced technologies to select competent blastocysts for transfer results in improved implantation and ongoing pregnancy rates for PGS patients.

A comprehensive study is presented of a series of 124 infertile men undergoing testicular sperm retrieval for intracytoplasmic sperm injection (ICSI). In this study we correlated the histological changes observed in the testicular tissue with the results of the wet preparation and the outcome after ICSI using testicular spermatozoa. In all patients with normal spermatogenesis and hypospermatogenesis spermatozoa were recovered from the wet preparation. The sperm recovery rate as 84% in patients with incomplete germ-cell-aplasia and maturation arrest, while in patients with complete germ-cell aplasia or maturation arrest this figure was 76%. In these patients more specimens were sampled and fewer spermatozoa were recovered. Since no spermatozoa were recovered in only 10 patients, ICSI with testicular sperm was performed in the remaining 114 couples (91.9%). The normal fertilization rate was 57. 8%. The fertilization rate was significantly lower in couples among whom the husband showed germ-cell aplasia and maturation arrest. Overall, 55.2% of normally fertilized oocytes developed into embryos showing

In seven patients who did not become pregnant following microsurgical epididymal sperm aspiration (MESA) and intracytoplasmic sperm injection (ICSI), a subsequent ICSI was performed using previously cryopreserved super-numerary epididymal spermatozoa without re-operating on the husband. During the original MESA procedure a mean sperm concentration of 12.3 x 10(6)/ml was achieved. The supernumerary spermatozoa were cryopreserved for later use. After thawing frozen epididymal spermatozoa a mean concentration of 1.9 x 10(6) spermatozoa/ml was obtained in straws containing a total volume of sperm suspension of 250 microliters. From 68 intact oocytes injected with frozen-thawed epididymal spermatozoa, a two pronuclear fertilization rate of 45% and a cleavage rate of 82% were obtained. A total of 17 embryos were replaced in the seven patients, resulting in two ongoing singleton pregnancies and one twin delivery. Six embryos were cryopreserved. In conclusion, it would appear mandatory to cryopreserve supernumerary spermatozoa during a MESA in order to avoid subsequent further scrotal surgery.

Knowledge of the timing of the stages of fertilization in humans is still limited because the time of gamete fusion is not known when pre-ovulatory or in-vitro matured cumulus-enclosed oocytes are inseminated. We therefore studied the morphological nuclear changes in 14 patients' oocytes by means of light microscopic observation at 2, 4, 6, 8, 16, 18 and at 20 h after intracytoplasmic single sperm injection (ICSI). A total of 144 metaphase II oocytes were injected with the spermatozoa of the patients' partners. Out of the 134 oocytes that survived the injection, 93 displayed two pronuclei in the course of the observation period (69%). Out of the 93 normally fertilized oocytes, 21 extruded the second polar body at 2 h after micro-injection (23%) and 63 oocytes at 4 h (68%). Pronuclei appeared as early as 6 h after ICSI in 16 normally fertilized oocytes (17%). At 8 h, 75 (80%) oocytes had two visible pronuclei, at 16 h 92 (99%), at 18 h 76 (82%) and at 20 h 63 (68%). In 24 oocytes (26%) the appearance of pronuclei was asynchronous, while the disappearance of the pronuclei was always synchronous, except in one oocyte. Nine of the 134 successfully injected oocytes showed three equal-sized pronuclei (6.7%). Four of the nine multi-pronucleated oocytes did not extrude the second polar body at all, while the time sequence of appearance of pronuclei was similar to that of the normally fertilized oocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to assess whether specific treatment of spermatozoa is required prior to intracytoplasmic sperm injection (ICSI), three methods of sperm preparation were compared in this study. These three methods were (A) incubation of spermatozoa with pentoxifylline (PTX) and 2-deoxyadenosine (DOA), (B) electroporation followed by incubation in medium with PTX, and (C) no further treatment with the Percoll gradient. Controlled comparisons were carried out between method A and method B in 21 patients, and between method A and method C in 32 patients. There was no difference in the rates of fertilization and embryo cleavage when ICSI was done with spermatozoa treated by procedures A, B or C. Furthermore, the sperm selection procedure prior to ICSI was done in two different media: T6 medium containing 1.78 mM CaCl2.2H2O and a final washing step after the Percoll gradient in T6 medium containing 5.0 mM CaCl2.2H2O, and Earle's medium containing 1.78 mM CaCl2.2H2O. The results of ICSI on sibling oocytes from 12 patients revealed no difference in the fertilization and embryo cleavage rates between the two different media used during the sperm selection procedures. In conclusion, it appears that high fertilization and pregnancy rates can be obtained in couples with severe male-factor infertility by ICSI and that no special treatment of the spermatozoa prior to ICSI is required.

Being noninvasive, low-risk and inexpensive, EEG is a promising methodology in the application of human Brain Computer Interface (BCI) to help those with motor dysfunctions. Here we employed a center-out task paradigm to study the decoding of hand velocity in the EEG recording. We tested the hypothesis using a linear regression model and found a significant correlation between velocity and the low-pass filtered EEG signal (

The efficiency of the polymerase chain reaction (PCR) in detecting the cystic fibrosis (CF) delta F508 mutation (which is the most common mutation of CF) was assessed in single human blastomeres. Twenty-one human immature oocytes (germinal-vesicle-stage oocytes) that had been donated for research were matured in vitro and a single spermatozoon from a carrier of the CF delta F508 mutation was injected into the ooplasm. Fourteen embryos were obtained after intracytoplasmic sperm injection (ICSI). PCR analysis was carried out on 70 single blastomeres isolated from these 14 embryos. The results showed that the efficiency of DNA amplification by PCR in single nucleate blastomeres was 94 per cent (59/63). There were no false-positive results since none of the blank samples or the blastomeres without a nucleus showed an amplified signal. We found that nine embryos were homozygous for the unaffected genotype and that four embryos were heterozygous since they contained both the unaffected and the delta F508 genotype. In a four-cell embryo, we observed the homozygous unaffected genotype in one blastomere and a heterozygous delta F508/unaffected genotype in the other three blastomeres.

We investigated the in-vitro and in-vivo development of cryopreserved and non-cryopreserved biopsied 8-cell mouse embryos, from which one to seven blastomeres were removed by micromanipulation. The results clearly indicate that the in-vitro and in-vivo development of biopsied 8-cell mouse embryos depended on the number of blastomeres removed: the more blastomeres removed, the greater the effect. When five, six, or seven blastomeres were removed, fewer blastocysts were formed. Furthermore, when these blastocysts were transferred to pseudopregnant females, no living young were formed, indicating the abnormality of these blastocysts. When up to three blastomeres were removed, there was no significant effect on the rate of in-vitro blastocyst formation. Living young were found even after the biopsy of four blastomeres, and after biopsy of only one or two blastomeres, the same percentage of living young was obtained as in the non-biopsied control embryos. Biopsied 8-cell mouse embryos were frozen and thawed in straws with 1,2-propanediol (1.5 M) and sucrose (0.1 M) with slow-freezing and rapid-thawing protocols. The survival after cryopreservation, defined as the percentage of embryos with the same number of blastomeres intact as the number of blastomeres before freezing, was excellent and no different from non-biopsied embryos, independent of the number of blastomeres biopsied. Furthermore, cryopreservation had no further impact on the in-vitro and in-vivo development of the biopsied embryos.

Previously reported better fertilization rate after intracytoplasmic single sperm injection (ICSI) than after subzonal insemination of several spermatozoa was confirmed in a controlled comparison of the two procedures in 11 patients. Intracytoplasmic sperm injection was carried out in 150 consecutive treatment cycles of 150 infertile couples, who had failed to have fertilized oocytes after standard in-vitro fertilization (IVF) procedures or who were not accepted for IVF because not enough motile spermatozoa were present in the ejaculate. A single spermatozoon was injected into the ooplasm of 1409 metaphase II oocytes. Only 117 oocytes (8.3%) were damaged by the procedure and 830 oocytes (64.2% of the successfully injected oocytes) had two distinct pronuclei the morning after the injection procedure. The fertilization rate was not influenced by semen characteristics. After 24 h of further in-vitro culture, 71.2% of these oocytes developed into embryos, which were transferred or cryopreserved. Only 15 patients did not have embryos replaced. Three-quarters of the transfers were triple-embryo transfers. High pregnancy rates were noticed since 67 pregnancies were achieved, of which 53 were clinical, i.e. a total and clinical pregnancy rate of 44.7% and 35.3% per started cycle and 49.6% and 39.2% per embryo transfer. A total of 237 supernumerary embryos were cryopreserved in 71 treatment cycles.

Objective : To determine the effect of hydrosalpinx fluid-containing medium on murine embryo development and implantation. Design : The development of one-, two-, and four-cell mouse embryos in medium containing 5%, 10%, and 20% of human hydrosalpinx fluid was observed. Implantation rates of mouse embryos transferred into the uterine horn with hydrosalpinx fluid-containing media were determined. Setting : Private hospital-based fertility center and IVF program. Main Outcome Measure(s) : Percentage of embryos continuing cell division and implantation rates after ET. Result(s) : Hydrosalpinx fluid in culture medium affected embryo development in a dosedependent fashion. The injection of hydrosalpinx fluid-containing medium into the uterine horn did not affect embryo implantation. Conclusion(s) : Hydrosalpinx fluid negatively affects murine embryo development, but its presence in the uterine horn at ET did not affect implantation.

Objective: To assess the feasibility of repeated fluorescence in situ hybridization (FISH) procedures in the same nucleus of a human blastomere. Design: Three consecutive FISH procedures were performed in the same human blastomere by using direct label fluorescence CEP and WCP probes (Vysis). Setting: Hospital-based private IVF program. Patient(s): Twenty-eight infertile couples who underwent conventional IVF in our center. Intervention(s): Embryos from oocytes with three pronuclei after in vitro insemination were used in this study. Main Outcome Measure(s): The rates of nuclear loss, present signals, and absent signal were examined. Result(s): In group 1, the rates of presence of signals were 94% after the first FISH, 92% after the second FISH, and 88% after the third FISH. In group 2, the rates of presence of signals were 96% after the first FISH, 93% after the second FISH, and 87% after the third FISH. There was no statistically significant difference in the rates of nuclear loss, present signals, and absent signal between three consecutive FISH procedures and between CEP and WCP probes. Conclusion(s): Six or more chromosomes of a single blastomere may be examined with use of this repeated FISH procedure, which may be important for preimplantation genetic diagnosis.

Objective: To report a high fertilization rate after intracytoplasmic sperm injection (ICSI) in patients with 100% nonmotile spermatozoa selected by a simple modified hypo-osmotic swelling test. Design: Clinical study. Setting: Hospital-based IVF center. Patient(s); Three couples with infertility due to asthenospermia. Intervention(s): The hypo-osmotic swelling test with 150-mOsm NaC1 solution was used to select viable spermatozoa before ICSI. Three patients provided semen samples and one of these three also had a testicular biopsy. Main Outcome Measure(s): Selection of viable spermatozoa using the hypo-osmotic swelling test with 150-mOsm NaC1 solution for ICSI. Result(s): No motile spermatozoa were found in three ejaculated semen samples and one testicular biopsy. Fifty-seven metaphase-II oocytes were injected with hypo-osmotic swelling test-positive ejaculated or testicular spermatozoa. Fifty-five (96.5%) of these oocytes were intact after injection. Forty-two (76.4%) of 55 oocytes showed two pronuclei, and 40 of the 42 fertilized oocytes cleaved. One patient had all embryos cryopreserved because of the risk of hyperstimulation; two other patients had embryos transferred. One ongoing pregnancy resulted. Conclusion: This hypo-osmotic swelling test with 150-mOsm NaC1 solution is a simple and efficient method for selection of viable spermatozoa. A high fertilization rate can be obtained using ICSI with viable spermatozoa selected by using this hypo-osmotic swelling test.

In order to find an optimal hypo-osmotic swelling test (HOST) and to identify viable sperm cells from patients with asthenozoospermia for intracytoplasmic sperm injection (ICSI), we tested single motile and non-motile spermatozoa in four hypo-osmotic solutions by micromanipulation. The four solutions were: A, H2O; B, 50 mOsm NaCl; C, 150 mOsm NaCl and D, 150 mOsm sodium citrate and fructose. Eosin Y staining was then carried out for evaluation of viability of the spermatozoa after HOST. Using motile spermatozoa, no statistical difference was found in HOST-positive spermatozoa between these four solutions. There were more viable sperm cells after HOST in solutions C and D, as noted by Eosin Y staining. After non-motile spermatozoa were incubated for 1 min in the four solutions, HOST with solution C gave the best results for identification of viable sperm cells compared to the other three solutions. When motile spermatozoa were incubated in solution C or solution D for 30 min, the result of HOST with solution C (10.8% dead spermatozoa) was superior to that of solution D (49.1% dead spermatozoa). In conclusion, the HOST protocol using 150 mOsm NaCl (solution C) for 1 min yielded the best results for selection of viable spermatozoa. This procedure should be used for selection of viable spermatozoa for ICSI in patients with 100% non-motile spermatozoa.

Objective To see whether testicular sperm extraction could be used to perform intracytoplasmic sperm injection (ICSI) for men with nonobstructive azoospermia caused by maturation arrest. Design Uncontrolled prospective trial of an attempt to find occasional elongated spermatids or spermatozoa in testes of azoospermic patients with maturation arrest and to use these haploid cells for ICSI. Setting European university-based center for reproductive medicine and private American community hospital. Patients Thirty-eight azoospermic males without obstruction and with biopsy-documented maturation arrest, seven of whom elected, with their wives, to undergo scrotal exploration and testicular sperm extraction with ICSI in an attempt to become pregnant. Interventions Histologic evaluation of spermatid development in 38 patients with azoospermic maturation arrest. Testicular sperm extraction with ICSI in seven random volunteers from this group. Main Outcome Measures Presence or absence of mature spermatids in the testis biopsy specimen of patients with azoospermic maturation arrest. Fertilization, cleavage, and pregnancy after testicular sperm extraction and ICSI in patients with azoospermic maturation arrest. Results All seven patients with azoospermic maturation arrest had occasional sperm found with testicular sperm extraction. Five had sufficient numbers (between 6 and 30) for ICSI, and those five had ETs. In four, the partners became pregnant. In all 38 patients examined, the maturation defect was in meiosis rather than in spermiogenesis. Conclusion Nonobstructive azoospermia caused by maturation arrest may be treated with testicular sperm extraction with ICSI apparently as successfully as Sertoli cell only.

Globozoospermia or round-headed spermatozoa is a rare type of teratozoospermia where the acrosome is absent resulting in male infertility with no known therapy. A few studies have shown that round-headed spermatozoa cannot bind to or penetrate the zona pellucida, and no normal fertilization has been observed in in-vitro fertilization (IVF) after insemination of human oocytes with round-headed spermatozoa. In this study, the fertilization capacity of round-headed spermatozoa after intracytoplasmic sperm injection (ICSI) into human oocytes has been examined. In pre-clinical experiments, 45 oocytes were injected; 41 oocytes were intact after injection, 15 oocytes were fertilized normally, and 13 of these 15 oocytes developed further in vitro. ICSI was carried out in 11 treatment cycles of seven infertile couples with globozoospermia. Normal fertilization and embryo transfer occurred in four cycles (three patients). Positive serum human chorionic gonadotrophin was observed in three cycles (two patients); one patient had a pre-clinical abortion and the other patient became pregnant twice; the first pregnancy was ectopic and the second pregnancy is a twin pregnancy which is currently at 16 weeks of gestation.

Objective To present and assess the efficacy of a new approach for the treatment of infertility due to congenital bilateral absence of the vas deferens. Design A retrospective study of consecutive trials. Setting Centre for Reproductive Medicine, which is a tertiary referral institution. Patients Twelve couples suffering from infertility because of congenital bilateral absence of the vas deferens. Interventions A microsurgical epididymal sperm aspiration procedure was performed in the husbands, followed by intracytoplasmic sperm injection of oocytes recovered from the wives. Cleaving embryos were transferred to the uterine cavity 48 hours after the intracytoplasmic sperm injection procedure. Main Outcome Measures Sperm parameters after microsurgical epididymal sperm aspiration, fertilization, cleavage, and pregnancy rates. Results In all 14 microsurgical epididymal sperm aspiration procedures, sperm was retrieved. Notwithstanding the poor quality of this epididymal sperm, a fertilization rate of 58% was achieved after intracytoplasmic sperm injection. On 10 occasions, embryos were transferred and five patients became pregnant, i.e., an overall pregnancy rate of 35.7% per started trial and 50.0% per transfer. Another two patients became pregnant after replacement of frozen-thawed embryos, which increases the pregnancy rate to 50.0% per microsurgical epididymal sperm aspiration procedure. Early pregnancy wastage was 57%, limiting the ongoing pregnancy rate to 21.4% per microsurgical epididymal sperm aspiration procedure. Conclusion This study shows the combined microsurgical epididymal sperm aspiration-intracytoplasmic sperm injection procedure to be highly efficient in achieving fertilization in vitro, even after recovery of grossly impaired epididymal sperm.

Men with congenital bilateral absence of the vas deferens (CBAVD) have been regarded as presenting a mild form of cystic fibrosis (CF). In this article, we report a case of male-factor infertility, in which both partners are carriers of the △F508 mutation and the male partner has CBAVD. Microsurgical epididymal sperm aspiration (MESA) was performed to obtain spermatozoa; intracytoplasmic sperm injection (ICSI) was carried out on the oocytes since the motility of the spermatozoa was severely impaired; and embryo biopsy and a polymerase chain reaction (PCR) were carried out for preimplantation diagnosis of the CF △F508 mutation. Single-blastomere analysis was performed and indicated that two embryos were affected (homozygous △F508) and three embryos were carriers. After transfer of the latter three embryos, a singleton pregnancy was established. At amniocentesis, the △F508 carrier status of the fetus with a 46, XY karyotype was confirmed. A healthy boy was born and the presence of vasa deferentia, bilaterally, was confirmed. The CF sweat test was also normal. Successful fertilization can be obtained by combination of MESA and ICSI in patients with CBAVD. Preimplantation diagnosis of CF is indicated. Pregnancy and birth of normal children can ensue in such patients. (JAMA. 1994;272:1858-1860)

The results of 600 consecutive treatment cycles of subzonal insemination (SUZI) and intracytoplasmic sperm injection (ICSI) are described in couples with failed fertilization after standard IVF or insufficient spermatozoa in the ejaculate for IVF. More oocytes were damaged by ICSI (16.3%) than by SUZI (8.5%) and the normal fertilization rate was substantially higher after ICSI (49.1% v. 16.6%). Subsequent development of two-pronuclear oocytes in vitro was 80% after SUZI and 73.9% after ICSI. Significantly more triple embryo replacements were carried out after ICSI than after SUZI. Embryo transfers were possible in 421 of the 600 cycles. There were 63 pregnancies after ICSI (215 transfers) and 23 after SUZI (156 transfers); 10 additional pregnancies were achieved after 50 transfers of a mixture of SUZI and ICSI embryos. The results of fetal karyotypes and follow-up of the children do not indicate an increase in congenital malformations.

Small, even vanishing neutrino masses are consistent with large CP violation effects in the leptonic sector. As an example, and a proof of existence of this situation, we present a model based on the SU(2)L × SU(2)R × U(1) gauge symmetry, where the fermion content has been Extended to include a gauge singlet lepton SL. Interesting features of this model (which should be seen as a mere example) are: (1) neutrino masses can either vanish or be in the range where the Mikheyev-Smirnov-Wolfenstein (MSW) mechanism for the solar neutrino puzzle is operative, and (2) CP violation effects in the lepton sector are manifestly large and therefore accessible to current experiments. In particular, it is found that the electron electric dipole moment, drme, can be of order 10−24e·cm; if generation mixing is negligible, the μ longitudinal polarization, PrmL, in the decay KL → μμ can be in the range 10−10−10−3.

In seven patients who did not become pregnant following microsurgical epididymal sperm aspiration (MESA) and intracytoplasmic sperm injection (ICSI), a subsequent ICSI was performed using previously cryopreserved super-numerary epididymal spermatozoa without re-operating on the husband. During the original MESA procedure a mean sperm concentration of 12.3 x 10(6)/ml was achieved. The supernumerary spermatozoa were cryopreserved for later use. After thawing frozen epididymal spermatozoa a mean concentration of 1.9 x 10(6) spermatozoa/ml was obtained in straws containing a total volume of sperm suspension of 250 microliters. From 68 intact oocytes injected with frozen-thawed epididymal spermatozoa, a two pronuclear fertilization rate of 45% and a cleavage rate of 82% were obtained. A total of 17 embryos were replaced in the seven patients, resulting in two ongoing singleton pregnancies and one twin delivery. Six embryos were cryopreserved. In conclusion, it would appear mandatory to cryopreserve supernumerary spermatozoa during a MESA in order to avoid subsequent further scrotal surgery.

Testicular biopsy has been widely used for the diagnosis of male infertility. Since the introduction of intracytoplasmic sperm injection (ICSI), spermatozoa recovered from a testicular biopsy specimen can be successfully used for establishing pregnancies. A few spermatozoa may be recovered from a wet preparation of a testicular biopsy, not only in obstructive azoospermic patients, but also in many patients with non-obstructive azoospermia. In 36 out of 38 non-obstructive azoospermic patients sperm cells were recovered from a testicular biopsy specimen. However in two patients, spermatozoa could not be found after further preparation of the biopsy specimens for ICSI. In the remaining 32 patients, a normal fertilization rate of 56.8% per successfully injected oocyte was obtained after ICSI of testicular spermatozoa. In 84% of patients, embryos were replaced with an overall pregnancy rate of 28.9% per testicular biopsy or 34.3% per embryo transfer. The results clearly indicate that at present an excisional testicular biopsy should be offered to all azoospermic patient, irrespective of concentration of follicle stimulating hormone, testicular size or medical history.