ABSTRACT
Neurosarcoidosis is one of the most relevant involvements in systemic sarcoidosis and can be the initial presentation. Its diagnosis is often considered difficult because of unusual clinical manifestations or diagnostic mimics. The peripheral nervous system is less frequently involved than the central nervous system, although it may also lead to irreversible neurologic impairment. Lumbosacral plexopathy in sarcoidosis is a rare presentation and has been scarcely described in anecdotal case reports and small case series. We describe the case of a 61-year-old female who presented with right inguinal pain, right thigh weakness, and gait limitation, with imaging evidence of bilateral lumbosacral plexopathy as the initial manifestation of systemic sarcoidosis and subsequently developed joint and pulmonary involvement. This case report aims to bring awareness of this involvement as a possible initial manifestation of systemic sarcoidosis and mention key features of the differential diagnosis. Prompt recognition and treatment may prevent neurologic impairment.
ABSTRACT
Hydroxychloroquine (HCQ) induced cardiotoxicity is a rare diagnosis and is often associated with chronic use of the medication. It has been shown that chronic HCQ use is associated with a drug-induced cardiomyopathy mainly driven by acquired lysosomal storage defects leading to hypertrophy and conduction abnormalities. As the only proven treatment is the discontinuation of the offending agent, prompt recognition is required to avoid further exposure to the drug and potential progression of disease. History, physical examination and advanced imaging modalities are useful diagnostic tools, but more invasive testing with an endomyocardial biopsy is required for definitive diagnosis. We present a descriptive case series of ten patients that were diagnosed with biopsy proven HCQ cardiotoxicity.
Subject(s)
Antirheumatic Agents , Cardiotoxicity , Hydroxychloroquine , Adult , Aged , Female , Humans , Male , Middle Aged , Antirheumatic Agents/adverse effects , Biopsy , Cardiomyopathies/chemically induced , Cardiotoxicity/etiology , Hydroxychloroquine/adverse effectsABSTRACT
Scleroderma is a chronic, progressive autoimmune disease that often presents with multiorgan involvement. Cardiac manifestations are common and include microvascular coronary artery disease, conduction abnormalities, autonomic insufficiency, and pericardial effusions. Although rare, pericardial effusions may progress and lead to cardiac tamponade. Patients diagnosed with scleroderma can be further prognosticated based on the presence of serologic scleroderma-specific antibodies. The anti-RNA polymerase III autoantibody (anti-RNAP3) is associated with an aggressive subtype of scleroderma. Looking at the current literature, no association has been reported between anti-RNAP3 and the development of cardiac tamponade in patients with underlying scleroderma. We discuss a unique case of a patient with scleroderma who was found to be anti-RNAP3 positive and signs of cardiac tamponade. This case illustrates the importance of an expeditious diagnosis and timely interventions to treat cardiac tamponade. Additionally, we share a rare but important association between anti-RNAP3 and the formation of tamponade physiology in scleroderma.
ABSTRACT
PURPOSE: Increased prostate cancer risk has been reported for BRCA mutation carriers, but BRCA-associated clinicopathologic features have not been clearly defined. EXPERIMENTAL DESIGN: We determined BRCA mutation prevalence in 832 Ashkenazi Jewish men diagnosed with localized prostate cancer between 1988 and 2007 and 454 Ashkenazi Jewish controls and compared clinical outcome measures among 26 BRCA mutation carriers and 806 noncarriers. Kruskal-Wallis tests were used to compare age of diagnosis and Gleason score, and logistic regression models were used to determine associations between carrier status, prostate cancer risk, and Gleason score. Hazard ratios (HR) for clinical end points were estimated using Cox proportional hazards models. RESULTS: BRCA2 mutations were associated with a 3-fold risk of prostate cancer [odds ratio, 3.18; 95% confidence interval (95% CI), 1.52-6.66; P = 0.002] and presented with more poorly differentiated (Gleason score > or =7) tumors (85% versus 57%; P = 0.0002) compared with non-BRCA-associated prostate cancer. BRCA1 mutations conferred no increased risk. After 7,254 person-years of follow-up, and adjusting for clinical stage, prostate-specific antigen, Gleason score, and treatment, BRCA2 and BRCA1 mutation carriers had a higher risk of recurrence [HR (95% CI), 2.41 (1.23-4.75) and 4.32 (1.31-13.62), respectively] and prostate cancer-specific death [HR (95% CI), 5.48 (2.03-14.79) and 5.16 (1.09-24.53), respectively] than noncarriers. CONCLUSIONS: BRCA2 mutation carriers had an increased risk of prostate cancer and a higher histologic grade, and BRCA1 or BRCA2 mutations were associated with a more aggressive clinical course. These results may have implications for tailoring clinical management of this subset of hereditary prostate cancer.
Subject(s)
Adenocarcinoma/genetics , Genes, BRCA1 , Genes, BRCA2 , Germ-Line Mutation , Prostatic Neoplasms/genetics , Adenocarcinoma/classification , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Gene Frequency , Genetic Carrier Screening , Genetic Predisposition to Disease , Germ-Line Mutation/physiology , Humans , Male , Middle Aged , Odds Ratio , Prostatic Neoplasms/classification , Prostatic Neoplasms/pathology , Risk FactorsABSTRACT
DNA polymerase X (pol X) from the African swine fever virus is a 174-amino-acid repair polymerase that likely participates in a viral base excision repair mechanism, characterized by low fidelity. Surprisingly, pol X's insertion rate of the G*G mispair is comparable to that of the four Watson-Crick base pairs. This behavior is in contrast with another X-family polymerase, DNA polymerase beta (pol beta), which inserts G*G mismatches poorly, and has higher DNA repair fidelity. Using molecular dynamics simulations, we previously provided support for an induced-fit mechanism for pol X in the presence of the correct incoming nucleotide. Here, we perform molecular dynamics simulations of pol X/DNA complexes with different incoming incorrect nucleotides in various orientations [C*C, A*G, and G*G (anti) and A*G and G*G (syn)] and compare the results to available kinetic data and prior modeling. Intriguingly, the simulations reveal that the G*G mispair with the incoming nucleotide in the syn configuration undergoes large-scale conformational changes similar to that observed in the presence of correct base pair (G*C). The base pairing in the G*G mispair is achieved via Hoogsteen hydrogen bonding with an overall geometry that is well poised for catalysis. Simulations for other mismatched base pairs show that an intermediate closed state is achieved for the A*G and G*G mispair with the incoming dGTP in anti conformation, while the protein remains near the open conformation for the C*C and the A*G syn mismatches. In addition, catalytic site geometry and base pairing at the nascent template-incoming nucleotide interaction reveal distortions and misalignments that range from moderate for A*G anti to worst for the C*C complex. These results agree well with kinetic data for pol X and provide a structural/dynamic basis to explain, at atomic level, the fidelity of this polymerase compared with other members of the X family. In particular, the more open and pliant active site of pol X, compared to pol beta, allows pol X to accommodate bulkier mismatches such as guanine opposite guanine, while the more structured and organized pol beta active site imposes higher discrimination, which results in higher fidelity. The possibility of syn conformers resonates with other low-fidelity enzymes such as Dpo4 (from the Y family), which readily accommodate oxidative lesions.
Subject(s)
African Swine Fever Virus/enzymology , Base Pair Mismatch , Base Pairing , Computer Simulation , DNA, Viral/chemistry , DNA-Directed DNA Polymerase/chemistry , Catalysis , Catalytic Domain , DNA Polymerase beta/chemistry , Kinetics , Magnesium/metabolism , Models, Molecular , Protein Structure, Secondary , Sequence Homology, Amino Acid , Templates, Genetic , Time FactorsABSTRACT
This article focuses on the role of advanced practice nurses as leaders on a health care team committed to providing a collaborative approach to a unique patient population. It describes the process of implementing a clinical trial for treatment of patients with neuroblastoma with the radioisotope 131I-MIBG. As new clinical trials emerge, staff nurses face challenges in providing care to complex patients and their families. Nurses are often required to acquire new knowledge, interact with other disciplines and departments, and develop new skills in order to provide care for these patients. Advanced practice nurses can provide a critical link between the principal investigator and staff members to meet these challenges. The process used to implement this trial can serve as a model for many other interdisciplinary projects.