Intra osseous transmigration of mandibular canines – A report of two cases

Background: A canine is classified as "transmigrated" when it crosses the midline. Transmigration of mandibular canines bilaterally is an extremely rare developmental dental ectopia with obscure etiology. Case Description: A 13 year old female and 10 year old male patient reported to the department with the chief complaint of missing teeth in the upper front teeth region and retained deciduous tooth in the lower front teeth region respectively. Panoramic radiographs revealed horizontally impacted permanent mandibular canines crossing the midline and located below the apices of the incisors. Based on the clinical, radiographic and CBCT findings, a diagnosis of transmigration of mandibular canines was established. Conclusion: Dental anomalies and pathologies such as cystic lesions, odontoma and root resorption of the adjacent teeth have been reported to be associated with transmigrated canines. Early diagnosis by radiographic evaluation and correction either by orthodontic intervention or by surgical transplantation is important to protect oral structures and preserve the canines to ensure facial harmony and improved function

Case Reports1. A Late Presentation of Loeys-Dietz Syndrome: Beware of TGFβ Receptor Mutations in Benign Joint Hypermobility

Background: Thoracic aortic aneurysms (TAA) and dissections are not uncommon causes of sudden death in young adults. Loeys-Dietz syndrome (LDS) is a rare, recently described, autosomal dominant, connective tissue disease characterized by aggressive arterial aneurysms, resulting from mutations in the transforming growth factor beta (TGFβ) receptor genes TGFBR1 and TGFBR2. Mean age at death is 26.1 years, most often due to aortic dissection. We report an unusually late presentation of LDS, diagnosed following elective surgery in a female with a long history of joint hypermobility. Methods: A 51-year-old Caucasian lady complained of chest pain and headache following a dural leak from spinal anaesthesia for an elective ankle arthroscopy. CT scan and echocardiography demonstrated a dilated aortic root and significant aortic regurgitation. MRA demonstrated aortic tortuosity, an infrarenal aortic aneurysm and aneurysms in the left renal and right internal mammary arteries. She underwent aortic root repair and aortic valve replacement. She had a background of long-standing joint pains secondary to hypermobility, easy bruising, unusual fracture susceptibility and mild bronchiectasis. She had one healthy child age 32, after which she suffered a uterine prolapse. Examination revealed mild Marfanoid features. Uvula, skin and ophthalmological examination was normal. Results: Fibrillin-1 testing for Marfan syndrome (MFS) was negative. Detection of a c.1270G > C (p.Gly424Arg) TGFBR2 mutation confirmed the diagnosis of LDS. Losartan was started for vascular protection. Conclusions: LDS is a severe inherited vasculopathy that usually presents in childhood. It is characterized by aortic root dilatation and ascending aneurysms. There is a higher risk of aortic dissection compared with MFS. Clinical features overlap with MFS and Ehlers Danlos syndrome Type IV, but differentiating dysmorphogenic features include ocular hypertelorism, bifid uvula and cleft palate. Echocardiography and MRA or CT scanning from head to pelvis is recommended to establish the extent of vascular involvement. Management involves early surgical intervention, including early valve-sparing aortic root replacement, genetic counselling and close monitoring in pregnancy. Despite being caused by loss of function mutations in either TGFβ receptor, paradoxical activation of TGFβ signalling is seen, suggesting that TGFβ antagonism may confer disease modifying effects similar to those observed in MFS. TGFβ antagonism can be achieved with angiotensin antagonists, such as Losartan, which is able to delay aortic aneurysm development in preclinical models and in patients with MFS. Our case emphasizes the importance of timely recognition of vasculopathy syndromes in patients with hypermobility and the need for early surgical intervention. It also highlights their heterogeneity and the potential for late presentation. Disclosures: The authors have declared no conflicts of interes

Marker assisted introgression of bacterial blight resistance in Samba Mahsuri, an elite indica rice variety

Samba Mahsuri (BPT5204) is a medium slender grain indica rice variety that is very popular with farmers and consumers across India because of its high yield and excellent cooking quality. However, the variety is susceptible to several diseases and pests, including bacterial blight (BB). We have used PCR based molecular markers in a backcross-breeding program to introgress three major BB resistance genes (Xa21, xa13 and xa5) into Samba Mahsuri from a donor line (SS1113) in which all the three genes are present in a homozygous condition. At each backcross generation, markers closely linked to the three genes were used to select plants possessing these resistance genes (foreground selection) and microsatellite markers polymorphic between donor and recurrent parent were used to select plants that have maximum contribution from the recurrent parent genome (background selection). A selected BC4F1 plant was selfed to generate homozygous BC4F2 plants with different combinations of BB resistance genes. The three-gene pyramid and two-gene pyramid lines exhibited high levels of resistance against the BB pathogen. Under conditions of BB infection, the three-gene pyramid lines exhibited a significant yield advantage over Samba Mahsuri. Most importantly, these lines retain the excellent grain and cooking qualities of Samba Mahsuri without compromising the yield as determined in multi-location trials. This work demonstrates the successful application of marker-assisted selection for targeted introgression of multiple resistance genes into a premium quality rice variety

Introduction of bacterial blight resistance into Triguna, a high yielding, mid-early duration rice variety

Bacterial blight (BB) is a serious disease of rice in India. We have used molecular marker-assisted selection in a backcross breeding program to introgress three genes (Xa21, xa13, and xa5) for BB resistance into Triguna, a mid-early duration, high yielding rice variety that is susceptible to BB. At each generation in the backcross program, molecular markers were used to select plants possessing these resistance genes and to select plants that have maximum contribution from the Triguna genome. A selected BC3F1 plant was selfed to generate homozygous BC<SUB>3</SUB>F<SUB>2</SUB> plants with different combinations of BB resistance genes. Plants containing the two-gene combination, Xa21 and xa13, were found to exhibit excellent resistance against BB. Single plant selections for superior agronomic characteristics were performed on the progeny of these plants, from BC<SUB>3</SUB>F<SUB>3</SUB> generation onwards. The selected plants were subjected to yield trials at the BC<SUB>3</SUB>F<SUB>8</SUB> generation and were found to have a significant yield advantage over Triguna. The newly developed lines are being entered into national multi-location field trials. This work represents a successful example of the application of molecular marker-assisted selection for BB resistance breeding in rice

Characteristics and Outcomes of Patients With Frailty Admitted to ICU With Coronavirus Disease 2019: An Individual Patient Data Meta-Analysis

: Frailty is often used in clinical decision-making for patients with coronavirus disease 2019, yet studies have found a variable influence of frailty on outcomes in those admitted to the ICU. In this individual patient data meta-analysis, we evaluated the characteristics and outcomes across the range of frailty in patients admitted to ICU with coronavirus disease 2019. Data sources: We contacted the corresponding authors of 16 eligible studies published between December 1, 2019, and February 28, 2021, reporting on patients with confirmed coronavirus disease 2019 admitted to ICU with a documented Clinical Frailty Scale. Study selection: Individual patient data were obtained from seven studies with documented Clinical Frailty Scale were included. We classified patients as nonfrail (Clinical Frailty Scale = 1-4) or frail (Clinical Frailty Scale = 5-8). Data extraction: We collected patient demographics, Clinical Frailty Scale score, ICU organ supports, and clinically relevant outcomes (ICU and hospital mortality, ICU and hospital length of stays, and discharge destination). The primary outcome was hospital mortality. Data synthesis: Of the 2,001 patients admitted to ICU, 388 (19.4%) were frail. Increasing age and Sequential Organ Failure Assessment score, Clinical Frailty Scale score greater than or equal to 4, use of mechanical ventilation, vasopressors, renal replacement therapy, and hyperlactatemia were risk factors for death in a multivariable analysis. Hospital mortality was higher in patients with frailty (65.2% vs 41.8%; p < 0.001), with adjusted mortality increasing with a rising Clinical Frailty Scale score beyond 3. Younger and nonfrail patients were more likely to receive mechanical ventilation. Patients with frailty spent less time on mechanical ventilation (median days [interquartile range], 9 [5-16] vs 11 d [6-18 d]; p = 0.012) and accounted for only 12.3% of total ICU bed days. Conclusions: Patients with frailty with coronavirus disease 2019 were commonly admitted to ICU and had greater hospital mortality but spent relatively fewer days in ICU when compared with nonfrail patients. Patients with frailty receiving mechanical ventilation were at greater risk of death than patients without frailty