A massive rock and ice avalanche caused the 2021 disaster at Chamoli, Indian Himalaya

On 7 February 2021, a catastrophic mass flow descended the Ronti Gad, Rishiganga, and Dhauliganga valleys in Chamoli, Uttarakhand, India, causing widespread devastation and severely damaging two hydropower projects. More than 200 people were killed or are missing. Our analysis of satellite imagery, seismic records, numerical model results, and eyewitness videos reveals that ~27 × 10⁶ cubic meters of rock and glacier ice collapsed from the steep north face of Ronti Peak. The rock and ice avalanche rapidly transformed into an extraordinarily large and mobile debris flow that transported boulders greater than 20 meters in diameter and scoured the valley walls up to 220 meters above the valley floor. The intersection of the hazard cascade with downvalley infrastructure resulted in a disaster, which highlights key questions about adequate monitoring and sustainable development in the Himalaya as well as other remote, high-mountain environments.

Biallelic mutations in FLNB cause a skeletal dysplasia with 46,XY gonadal dysgenesis by activating β-catenin

Filamin B (FLNB) functions as a switch that can affect chrondrocyte development and endochondral bone formation through a series of signaling molecules and transcription factors that also affect Sertoli cell development. Here, we report a subject with a novel skeletal dysplasia and co-existing 46,XY gonadal dysgenesis and biallelic mutations in FLNB. Whole exome sequencing was performed to identify mutations. Quantitative polymerase chain reaction (qPCR) and flow variant assays were performed to quantify RNA, proteins and phosphorylated proteins. The TOPFLASH reporter was performed to quantify β-catenin activity. Mutations were identified in the FLNB gene (FLNB:p.F964L, FLNB:p.A1577V). These mutations increased binding of FLNB protein to the MAP3K1 and RAC1 signal transduction complex and activated β-catenin and had different effects on phosphorylation of MAP kinase pathway intermediates and SOX9 expression. Direct activation of β-catenin through the FLNB-MAP3K1-RAC1 complex by FLNB mutations is a novel mechanism for causing 46,XY gonadal dysgenesis. The mechanism of action varies from those reported previously for loss of function mutations in SOX9 and gain-of-function mutations in MAP3K1.

Development and characterization of phyto-vesicles of wedelolactone for hepatoprotective activity

Wedelolactone is isolated from the dried leaves of Eclipta alba (L.) and reported to be effective as a potential hepatoprotective, antibacterial and anti hemorrhagic. Pharmacokinetic studies of wedelolactone reveal its poor absorption through the intestine. The objective of the present study is to enhance bioavailability of wedelolactone by its complexation with phosphatidyl choline and then formulating it as phyto-vesicles for hepatoprotective activity. The complex of wedelolactone rich fraction was prepared with phosphatidyl choline and characterized on the basis of solubility, melting point, thin layer chromatography (TLC), UV, IR and NMR spectroscopy. The complex was further converted into phyto-vesicles and characterized. The hepatoprotective potential of phyto-vesicles was compared with complex, wedelolactone rich fraction and physical mixture of wedelolactone rich fraction and phosphatidyl choline by in vitro method. The results revealed that hepatoprotective activity is better in case of phyto-vesicles as compared to the complex, physical mixture and the wedelolactone itself. Enhanced bioavailability of the wedelolactone complex may be due to the amphiphillic nature of the complex, which greatly enhance the water and lipid solubility of the compound. The present study clearly indicates the superiority of phyto-vesicles over the complex and wedelolactone, in terms of better absorption and improved hepatoprotective activity.

Congenital Myotonic Dystrophy

We describe a case of severe congenital myotonic dystrophy (CDM). A 38-year-old primigravida, who was known to suffer from mild myotonic dystrophy (DM), conceived spontaneously and booked for confinement at 11 weeks in our unit. The couple had been fully counseled about the risks of transmission of this condition to their offspring before embarking on this pregnancy. Despite being fully aware of the risks, they declined prenatal diagnosis. The pregnancy was monitored by serial ultrasound scans. The diagnosis of CDM was suspected by ultrasound markers of borderline ventriculomegaly, polyhydramnios, and reduced fetal movements. The pregnancy ended prematurely at 33 weeks in an emergency caesarean section because of severe fetal compromise. The neonate died almost immediately after birth. The genetic analysis of cord blood confirmed severe DM. This case highlights the importance of ultrasound markers for the diagnosis of CDM in the absence of definitive prenatal diagnosis.