Hysteroscopic Metroplasty Using Holmium: YAG Laser for Treatment of Septate Uterus.

STUDY OBJECTIVE: To demonstrate the safety, efficacy, and ease of hysteroscopic metroplasty using holmium:YAG (Ho:YAG) laser for treatment of septate uterus. DESIGN: Stepwise demonstration of surgical technique with narrated video footage. SETTING: Septate uterus is the most common type of uterine anomaly. The incidence of uterine septum in women presenting with infertility and recurrent abortions is 15.4% [1,2]. Hysteroscopic septal incision is associated with improvement in live-birth rate in these women [3]. Hysteroscopic metroplasty for septate uterus can be done with the use of scissors and energy sources such as monopolar and bipolar electrosurgery and lasers. Ho:YAG laser is commonly used by urologists for various surgeries because of its "Swiss Army Knife" action of cutting, coagulation, and vaporization [4]. Ho:YAG laser is known for its precision. It causes lesser depth of tissue injury and necrosis and minimal collateral thermal damage compared with the electrosurgical devices and other lasers used for hysteroscopic surgery [5-8]. This is advantageous in hysteroscopic metroplasty given that it reduces the risk of uterine perforation during surgery and hence uterine rupture in the subsequent pregnancy. Reduced collateral damage to the surrounding endometrium helps promote early endometrial healing and prevent postoperative intrauterine adhesions. A 28-year-old patient with history of 2 spontaneous abortions came to our hospital for investigations. 3D transvaginal sonography of the patient showed presence of partial septate uterus with a fundal indentation of 1.5 cm (Supplemental video 1). INTERVENTION: Diagnostic hysteroscopy followed by septal incision using Ho: YAG laser was planned. We used a 2.9 mm BETTOCCHI Hysteroscope (Karl Storz SE & Co.) with a 5 mm operative sheath. Normal saline was used as the distending medium and the intrauterine pressure was maintained at 80 to 100 mm Hg. The procedure was done under total intravenous anesthesia using propofol injection. Vaginoscopic entry into the uterus (without any cervical dilatation) showed evidence of a partial uterine septum with tubal ostia on either side of the septum. A 400 micron quartz fiber was passed through a laser guide into the 5-Fr working channel of the operative hysteroscope. Ho:YAG laser (Auriga XL 50-Watt, Boston Scientific) with power settings of 15 watts (1500 mJ energy at 10 Hz) was used. Incision of the septum was started at the apex of the septum in the midline and continued in a horizontal manner from side to side toward the base (Supplemental video 2). Incision of the septum is continued till the tip of the hysteroscope can move freely from one ostium to the other (Supplemental video 3). The operative time was 12 minutes. There were no intra- or postoperative complications. Postoperative estrogen therapy was given for 2 months in the form of estradiol valerate 2 mg (tablet, Progynova, Zydus Cadila) 12 hourly orally for 25 days and medroxyprogesterone acetate 10 mg (tablet, Meprate, Serum Institute of India, Ltd) 12 hourly orally added in the last 5 days [9]. 3D transvaginal ultrasound was done on day 8 of menses. It showed a triangular uterine cavity with a very small fundal indentation of 0.37 cm. A second look hysteroscopy that was done on day 9 of menses showed an uterine cavity of good shape and size [10]. Few fundal adhesions were seen and they were incised using Ho:YAG laser. The patient conceived 5 months after the primary surgery and delivered by cesarean section at 38 weeks, giving birth to a healthy baby of 2860 grams. There were no complications during her pregnancy and delivery. A comparative study is essential to prove its advantages over other energy sources for this surgery. CONCLUSION: Hysteroscopic metroplasty using Ho:YAG laser for treatment of septate uterus is a simple, precise, safe, and effective procedure. VIDEO ABSTRACT.

Modulation of LPA receptor expression in the human brain following neurotrauma.

Lysophosphatidic acid (LPA) is involved in physiological and pathological states, including in neural development and inflammation. We assessed the expression pattern of the LPA receptors 1-3 and of LPA-producing enzyme autotaxin in post-mortem human brain tissue, both in normal individuals and in individuals who died following traumatic brain injury. We found that LPA receptors and autotaxin are weakly expressed in the normal control adult brain. Quantitative PCR for the LPA receptors and autotaxin mRNA showed an increase of LPAR(2) and a decrease of autotaxin mRNA expression in the cortex following brain injury. Immunohistochemical analysis showed that LPAR(1) colocalized with astrocytes and that LPAR(2) is present on the ependymal cells lining the lateral ventricle in the brain samples from individuals who died following severe head injury. This work shows for the first time that key components of the LPA pathway are modulated following TBI in humans.

Single cell RNA sequencing of stem cell-derived retinal ganglion cells.

We used single cell sequencing technology to characterize the transcriptomes of 1,174 human embryonic stem cell-derived retinal ganglion cells (RGCs) at the single cell level. The human embryonic stem cell line BRN3B-mCherry (A81-H7), was differentiated to RGCs using a guided differentiation approach. Cells were harvested at day 36 and prepared for single cell RNA sequencing. Our data indicates the presence of three distinct subpopulations of cells, with various degrees of maturity. One cluster of 288 cells showed increased expression of genes involved in axon guidance together with semaphorin interactions, cell-extracellular matrix interactions and ECM proteoglycans, suggestive of a more mature RGC phenotype.

Single-Cell Profiling Identifies Key Pathways Expressed by iPSCs Cultured in Different Commercial Media.

We assessed the pluripotency of human induced pluripotent stem cells (iPSCs) maintained on an automated platform using StemFlex and TeSR-E8 media. Analysis of transcriptome of single cells revealed similar expression of core pluripotency genes, as well as genes associated with naive and primed states of pluripotency. Analysis of individual cells from four samples consisting of two different iPSC lines each grown in the two culture media revealed a shared subpopulation structure with three main subpopulations different in pluripotency states. By implementing a machine learning approach, we estimated that most cells within each subpopulation are very similar between all four samples. The single-cell RNA sequencing analysis of iPSC lines grown in both media reports the molecular signature in StemFlex medium and how it compares to that observed in the TeSR-E8 medium.

Friedreich's ataxia induced pluripotent stem cell-derived cardiomyocytes display electrophysiological abnormalities and calcium handling deficiency.

We sought to identify the impacts of Friedreich's ataxia (FRDA) on cardiomyocytes. FRDA is an autosomal recessive degenerative condition with neuronal and non-neuronal manifestations, the latter including progressive cardiomyopathy of the left ventricle, the leading cause of death in FRDA. Little is known about the cellular pathogenesis of FRDA in cardiomyocytes. Induced pluripotent stem cells (iPSCs) were derived from three FRDA individuals with characterized GAA repeats. The cells were differentiated into cardiomyocytes to assess phenotypes. FRDA iPSC- cardiomyocytes retained low levels of FRATAXIN (FXN) mRNA and protein. Electrophysiology revealed an increased variation of FRDA- cardiomyocyte beating rates which was prevented by addition of nifedipine, suggestive of a calcium handling deficiency. Finally, calcium imaging was performed and we identified small amplitude, diastolic and systolic calcium transients confirming a deficiency in calcium handling. We defined a robust FRDA cardiac-specific electrophysiological profile in patient-derived iPSCs which could be used for high throughput compound screening. This cell-specific signature will contribute to the identification and screening of novel treatments for this life-threatening disease.

Development of a Modular Automated System for Maintenance and Differentiation of Adherent Human Pluripotent Stem Cells.

Patient-specific induced pluripotent stem cells (iPSCs) have tremendous potential for development of regenerative medicine, disease modeling, and drug discovery. However, the processes of reprogramming, maintenance, and differentiation are labor intensive and subject to intertechnician variability. To address these issues, we established and optimized protocols to allow for the automated maintenance of reprogrammed somatic cells into iPSCs to enable the large-scale culture and passaging of human pluripotent stem cells (PSCs) using a customized TECAN Freedom EVO. Generation of iPSCs was performed offline by nucleofection followed by selection of TRA-1-60-positive cells using a Miltenyi MultiMACS24 Separator. Pluripotency markers were assessed to confirm pluripotency of the generated iPSCs. Passaging was performed using an enzyme-free dissociation method. Proof of concept of differentiation was obtained by differentiating human PSCs into cells of the retinal lineage. Key advantages of this automated approach are the ability to increase sample size, reduce variability during reprogramming or differentiation, and enable medium- to high-throughput analysis of human PSCs and derivatives. These techniques will become increasingly important with the emergence of clinical trials using stem cells.

Characterization of the retinal pigment epithelium in Friedreich ataxia.

We assessed structural elements of the retina in individuals with Friedreich ataxia (FRDA) and in mouse models of FRDA, as well as functions of the retinal pigment epithelium (RPE) in FRDA using induced pluripotent stem cells (iPSCs). We analyzed the retina of the FRDA mouse models YG22R and YG8R containing a human FRATAXIN (FXN) transgene by histology. We complemented this work with post-mortem evaluation of eyes from FRDA patients. Finally, we derived RPE cells from patient FRDA-iPSCs to assess oxidative phosphorylation (OXPHOS) and phagocytosis. We showed that whilst the YG22R and YG8R mouse models display elements of retinal degeneration, they do not recapitulate the loss of retinal ganglion cells (RGCs) found in the human disease. Further, RPE cells differentiated from human FRDA-iPSCs showed normal OXPHOS and we did not observe functional impairment of the RPE in Humans.

The effects of CYP3A4, CYP3A5, ABCB1, ABCC2, ABCG2 and SLCO1B3 single nucleotide polymorphisms on the pharmacokinetics and pharmacodynamics of docetaxel in nasopharyngeal carcinoma patients.

PURPOSE: This exploratory study aimed to explain the interindividual variabilities of docetaxel pharmacokinetics and pharmacodynamics in Asian nasopharyngeal carcinoma patients (n = 54) through the genotyping of CYP3A4, CYP3A5, ABCB1, ABCC2, ABCG2 and SLCO1B3 genes. METHODS: Docetaxel was administered over 1 h on days 1, 8, and 15 every 28 days at 30 mg/m(2)/dose. Genomic DNA was isolated from peripheral blood and genotyped for the selected polymorphisms in the candidate genes. Docetaxel pharmacokinetic parameters were estimated by non-compartmental modelling. RESULTS: Patients homozygous for the variant allele (GG) of SLCO1B3 rs11045585 (IVS12-5676A > G) had significantly higher area under the plasma concentration-time curve of docetaxel (P = 0.026) and lower clearance (P = 0.036) compared to patients with AA/AG genotypes. Patients harbouring the heterozygous genotype (GA + GT + TA) for ABCB1 rs2032582 (2677G > T/A) had the highest percentage decrease in nadir haemoglobin from cycle 1 baseline compared to those with GG/TT genotypes (P = 0.006). Similar trend was observed for ABCB1 rs1045642 (3435C > T) with heterozygotes (CT) having the highest percentage decrease in nadir haemoglobin from cycle 1 baseline compared to those with CC/TT genotypes (P = 0.066). CONCLUSIONS: This study suggests that the cooperative influence of functional polymorphisms in SLCO1B3 and ABCB1 genes may be responsible for the interindividual variability in docetaxel disposition in Asian nasopharyngeal cancer patients.