Assessment of genome mutation analysis for tumor-informed detection of circulating tumor DNA in patients with breast cancer.

INTRODUCTION: Breast cancer, one of the most aggressive types of cancer, poses significant challenges for diagnosis and treatment. Emerging as a promising biomarker, circulating tumor DNA (ctDNA) can be used to identify and monitor disease risk. This study sought to examine the impact of mutations in various genes on the progression of breast cancer. Genetic variants associated with breast cancer have been examined in individuals diagnosed with the disease worldwide. METHODS: Fifty female participants underwent breast cancer testing. Sanger sequencing was used to analyze peripheral blood DNA from these individuals to detect disease-causing mutations in the BRCA1, BRCA2, PTEN, TP53, and ATM genes. Genetic alterations linked to breast cancer were screened and the findings were compared with those of tumor genes. RESULTS: The development of hereditary/early onset breast cancer in this study was significantly associated with mutations in ATM, PTEN, TP53, and BRCA1/BRCA2, according to the analysis of sequencing data. CONCLUSION: This study demonstrates the feasibility of analyzing ctDNA in patients with breast cancer (BC) undergoing palliative treatment using an SS-based technique.

Chaos and localized phases in a two-body linear kicked rotor system.

Despite the periodic kicks, a linear kicked rotor (LKR) is an integrable and exactly solvable model in which the kinetic energy term is linear in momentum. It was recently shown that spatially interacting LKRs are also integrable, and results in dynamical localization in the corresponding quantum regime. Similar localized phases exist in other nonintegrable models such as the coupled relativistic kicked rotors. This work, using a two-body LKR, demonstrates two main results; first, it is shown that chaos can be induced in the integrable linear kicked rotor through interactions between the momenta of rotors. An analytical estimate of its Lyapunov exponent is obtained. Second, the quantum dynamics of this chaotic model, upon variation of kicking and interaction strengths, is shown to exhibit a variety of phases: classically induced localization, dynamical localization, subdiffusive, and diffusive phases. We point out the signatures of these phases from the perspective of entanglement production in this system. By defining an effective Hilbert space dimension, the entanglement growth rate can be understood using appropriate random matrix averages.

Interaction-induced directed transport in quantum chaotic subsystems.

Quantum directed transport can be realized in noninteracting, deterministic, chaotic systems by appropriately breaking the spatiotemporal symmetries in the potential. In this work, the focus is on the class of interacting two-body quantum systems whose classical limit is chaotic. It is shown that one subsystem effectively acts as a source of "noise" to the other leading to intrinsic temporal symmetry breaking. Then, the quantum directed currents, even if prohibited by symmetries in the composite system, can be realized in the subsystems. This current is of quantum origin and does not arise from semiclassical effects. This protocol provides a minimal framework-broken spatial symmetry in the potential and presence of interactions-for realizing directed transport in interacting chaotic systems. It is also shown that the magnitude of directed current undergoes multiple current reversals upon varying the interaction strength and this allows for controlling the currents. It is explicitly demonstrated in the two-body interacting kicked rotor model. The interaction-induced mechanism for subsystem directed currents would be applicable to other interacting quantum systems as well.

Interplay between quantum diffusion and localization in the atom-optics kicked rotor.

Atom-optics kicked rotor represents an experimentally reliable version of the paradigmatic quantum kicked rotor system. In this system, a periodic sequence of kicks are imparted to the cold atomic cloud. After a short initial diffusive phase the cloud settles down to a stationary state due to the onset of dynamical localization. In this paper, to explore the interplay between localized and diffusive phases, we experimentally implement a modification to this system in which the sign of the kick sequence is flipped after every M kicks. This is achieved in our experiment by allowing free evolution for half the Talbot time after every M kicks. Depending on the value of M, this modified system displays a combination of enhanced diffusion followed by asymptotic localization. This is explained as resulting from two competing processes-localization induced by standard kicked rotor type kicks, and diffusion induced by the half Talbot time evolution. The experimental and numerical simulations agree with one another. The evolving states display localized but nonexponential wave function profiles. This provides another route to quantum control in the kicked rotor class of systems.

Late perforation of Durata ICD lead--a case report.

Late ICD lead perforation is an uncommon but clinically significant complication. The pathophysiology, predictors, clinical presentations and management although have been described earlier but still remain inconclusive. Our case highlights the challenges involved in clinical recognition, the value of CT scan in its diagnosis and need for careful management of this potentially life threatening condition. It is the first report on Durata lead perforation to the best of our knowledge.

Thymic seminoma.

Thymic seminoma is a rare clinical entity. We report a case of an 18-year-old male patient who presented with chest pain, dyspnea, dysphagia of 1-month duration. Contrast-enhanced computer tomogram of chest showed an anterior mediastinal mass. He was subjected to thoracotomy and excision of the mass. Histopathology examination revealed seminoma of thymus. He failed to follow up for a period of 8 months post-surgery as he was asymptomatic. He then presented with a recurrence of the tumor locally, along with metastases to the lung, para-aortic and peri-aortic lymph nodes. He was kept on cisplatin, bleomycin and etoposide.