A prospective study on risk factors associated with the development of isthmocele after caesarean section.

OBJECTIVES: The primary objective was to detect the number of women developing isthmocele following lower segment caesarean section. The secondary objectives included analysing the risk factors associated with developing isthmocele and measuring the agreement between Transvaginal Ultrasonography (TVS) and Saline infusion Sonohysterography (SIS) in diagnosing Isthmocele. METHODS: This study was conducted in the Department of Obstetrics and Gynecology and focused on women who had undergone Lower Segment cesarean Section (LSCS). The study aimed to detect any indentation of at least 2 mm in the scar site, known as isthmocele, using Transvaginal Ultrasound (TVS) and Saline Infusion Sonography (SIS) between 6 weeks and 6 months after delivery. Along with the primary objective, the study also evaluated several secondary outcomes such as maternal comorbidities, closure techniques, and labor details. The evaluation of isthmocele followed the 2019 modified Delphi consensus approach. RESULTS: In our study, we found that 30% of our study population had isthmocele. We also observed that the number of previous caesarean deliveries, maternal BMI, duration of surgery, and characteristics of the previous CD scar were significantly associated with the development of isthmocele. When we compared the diagnostic methods, we found that TVS and SIS had similar limits of agreement for clinically important isthmocele parameters. However, we noticed a difference in the length and distance of isthmocele from the internal os, which we observed through Bland Altman plots. CONCLUSION: Our research has shown that women who have undergone multiple caesarean deliveries, have a higher maternal body mass index (BMI), and experienced longer surgery duration are at a significantly higher risk of developing isthmocele. To prevent its development, it is recommended to promote vaginal birth after caesarean delivery whenever feasible, manage maternal obesity early on, and provide adequate surgical training to medical professionals. Additionally, transvaginal ultrasound (TVS) is an effective method for detecting isthmocele and can be used interchangeably with saline-infused sonography (SIS).

A rare case of squamous cell carcinoma associated with a huge ovarian dermoid cyst in a postmenopausal woman.

Malignant transformation of mature cystic teratoma (MCT) is a well-known but uncommon phenomenon seen mostly in postmenopause women. We report a case of a 65-year-old postmenopausal woman with a malignant transformation of MCT and with a low-grade squamous intraepithelial lesion in her cervix. She was treated surgically by total abdominal hysterectomy with bilateral salpingo-oophorectomy with a preoperative diagnosis of right ovarian teratoma. Her postoperative period was uneventful. On follow-up, the histopathology report revealed a right ovarian dermoid cyst with well-differentiated squamous cell carcinoma; there was no evidence of malignancy elsewhere, including the cervix. Ascitic fluid was also free of malignant cells, and the disease was at stage Ia. The patient did not receive any adjuvant chemotherapy and was followed up with clinical examination postoperatively for 1 year, and there was no evidence of any relapse clinically. Preoperative diagnosis of malignant transformation of squamous cell carcinoma (SCC) is difficult, as there is no specific screening marker and no consensus or standard guidelines available regarding the optimum management of this relatively poorly known entity. Here we emphasize the need for a high index of suspicion of malignant transformation with the presence of factors such as elderly age, the huge size of the tumor, and large solid components in the tumor. Considering the scarcity of case reports and studies about SCC arising from MCT, every experience with malignant transformation of MCT should be reported for a better understanding of the disease presentation and management.

OsRuvBL1a DNA helicase boost salinity and drought tolerance in transgenic indica rice raised by in planta transformation.

RuvBL, is a member of SF6 superfamily of helicases and is conserved among the various model systems. Recently, rice (Oryza sativa L.) homolog of RuvBL has been biochemically characterized for its ATPase and DNA helicase activities; however its involvement in stress has not been studied so far. Present investigation reports the detailed functional characterization of OsRuvBL under abiotic stresses through genetic engineering. An efficient Agrobacterium-mediated in planta transformation protocol was developed in indica rice to generate the transgenic lines and study was focused on optimization of factors to achieve maximum transformation efficiency. Overexpressing OsRuvBL1a transgenic lines showed enhanced tolerance under in vivo salinity stress as compared to WT plants. The physiological and biochemical analysis of the OsRuvBL1a transgenic lines showed better performance under salinity and drought stresses. Several stress responsive interacting partners of OsRuvBL1a were identified using Y2H system revealed to its role in stress tolerance. Functional mechanism for boosting stress tolerance by OsRuvBL1a has been proposed in this study. This integration of OsRuvBL1a gene in rice genome using in planta transformation method helped to achieve the abiotic stress resilient smart crop. This study is the first direct evidence to show the novel function of RuvBL in boosting abiotic stress tolerance in plants.

Rice lectin receptor-like kinase provides salinity tolerance by ion homeostasis.

Sensing stress and activating the downstream signaling pathways is the imperative step for stress response. Lectin receptor-like kinase (LecRLK) is an important family that plays a key role in sensing stress conditions through lectin receptor and activates downstream signaling by kinase domain. We identified the role of OsLecRLK gene for salinity stress tolerance and hypothesized its role in Na+ extrusion from cell. OsLecRLK overexpression and downregulation (through artificial miRNA) transgenic lines were developed and its comparison with wild-type (WT) plants were performed overexpression transgenic lines showed better performance, whereas downregulation showed poor performance than WT. Lower accumulation of reactive oxygen species (ROS), malondialdehyde and toxic ion, and a higher level of proline, RWC, ROS scavengers in overexpression lines lead us to the above conclusion. Based on the relative expression of stress-responsive genes, ionic content and interactome protein, working model highlights the role of OsLecRLK in the extrusion of Na+ ion from the cell. This extrusion is facilitated by a higher expression of salt overly sensitive 1 (Na+ /K+ channel) in overexpression transgenic line. Altered expression of stress-responsive genes and changed biochemical and physiological properties of cell suggests an extensive reprogramming of the stress-responsive metabolic pathways by OsLecRLK under stress condition, which could be responsible for the salt tolerance capability.

Marker-free transgenic rice plant overexpressing pea LecRLK imparts salinity tolerance by inhibiting sodium accumulation.

KEY MESSAGE: PsLecRLK overexpression in rice provides tolerance against salinity stress and cause upregulation of SOS1 pathway genes, which are responsible for extrusion of excess Na+ ion under stress condition. Soil salinity is one of the most devastating factors threatening cultivable land. Rice is a major staple crop and immensely affected by soil salinity. The small genome size of rice relative to wheat and barley, together with its salt sensitivity, makes it an ideal candidate for studies on salt stress response caused by a particular gene. Under stress conditions crosstalk between organelles and cell to cell response is imperative. LecRLK is an important family, which plays a key role under stress conditions and regulates the physiology of the plant. Here we have functionally validated the PsLecRLK gene in rice for salinity stress tolerance and hypothesized the model for its working. Salt stress sensitive rice variety IR64 was used for developing marker-free transgenic with modified binary vector pCAMBIA1300 overexpressing PsLecRLK gene. Comparison of transgenic and wild-type (WT) plants showed better physiological and biochemical results in transgenic lines with a low level of ROS, MDA and ion accumulation and a higher level of proline, relative water content, root/shoot ration, enzymatic activities of ROS scavengers and upregulation of stress-responsive genes. Based on the relative expression of stress-responsive genes and ionic content, the working model highlights the role of PsLecRLK in the extrusion of Na+ ion from the cell. This extrusion of Na+ ion is facilitated by higher expression of SOS1 (Na+/K+ channel) in transgenic plants as compared to WT plants. Altered expression of stress-responsive genes and change in biochemical and physiological properties of the cell suggests an extensive reprogramming of the stress-responsive metabolic pathways by PsLecRLK under stress condition, which could be responsible for the salt tolerance capability.

Stress-induced Oryza sativa RuvBL1a is DNA-independent ATPase and unwinds DNA duplex in 3' to 5' direction.

RuvB, a member of AAA+ (ATPases Associated with diverse cellular Activities) superfamily of proteins, is essential, highly conserved and multifunctional in nature as it is involved in DNA damage repair, mitotic assembly, switching of histone variants and assembly of telomerase core complex. RuvB family is widely studied in various systems such as Escherichia coli, yeast, human, Drosophila, Plasmodium falciparum and mouse, but not well studied in plants. We have studied the transcript level of rice homologue of RuvB gene (OsRuvBL1a) under various abiotic stress conditions, and the results suggest that it is upregulated under salinity, cold and heat stress. Therefore, the OsRuvBL1a protein was characterized using in silico and biochemical approaches. In silico study confirmed the presence of all the four characteristic motifs of AAA+ superfamily-Walker A, Walker B, Sensor I and Sensor II. Structurally, OsRuvBL1a is similar to RuvB1 from Chaetomium thermophilum. The purified recombinant OsRuvBL1a protein shows unique DNA-independent ATPase activity. Using site-directed mutagenesis, the importance of two conserved motifs (Walker B and Sensor I) in ATPase activity has been also reported with mutants D302N and N332H. The OsRuvBL1a protein unwinds the duplex DNA in the 3' to 5' direction. The presence of unique DNA-independent ATPase and DNA unwinding activities of OsRuvBL1a protein and upregulation of its transcript under abiotic stress conditions suggest its involvement in multiple cellular pathways. The first detailed characterization of plant RuvBL1a in this study may provide important contribution in exploiting the role of RuvB for developing the stress tolerant plants of agricultural importance.

Rhodium-Catalyzed Enantioselective Isomerization of meso-Oxabenzonorbornadienes to 1,2-Naphthalene Oxides.

Herein we describe a rhodium-catalyzed enantioselective isomerization of meso-oxabicyclic alkenes to 1,2-naphthalene oxides. These potentially useful building blocks can be accessed in moderate to excellent yields with impressive enantioselectivities. Additionally, experimental findings supported by preliminary computations suggest that ring-opening reactions of bridgehead disubstituted oxabicyclic alkenes proceed through the intermediacy of these epoxides and may point to a kinetically and thermodynamically favored reductive elimination as the origin for the observed enantioselectivities.

Rhodium-Catalyzed Asymmetric Cycloisomerization and Parallel Kinetic Resolution of Racemic Oxabicycles.

While desymmetrizations by intermolecular asymmetric ring-opening reactions of oxabicyclic alkenes with various nucleophiles have been reported over the past two decades, the demonstration of an intramolecular variant is unknown. Reported herein is the first rhodium-catalyzed asymmetric cycloisomerization of meso-oxabicyclic alkenes tethered to bridgehead nucleophiles, thus providing access to tricyclic scaffolds through a myriad of enantioselective C-O, C-N, and C-C bond formations. Moreover, we also demonstrate a unique parallel kinetic resolution, whereby racemic oxabicycles bearing two different bridgehead nucleophiles can be resolved enantioselectively.