In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

[EX Q]: Context: Enterovirus infections are major etiological factors in myocarditis and dilated cardiomyopathy. Using an experimental murine model of this disease, previous studies have shown that myocarditis susceptibility depends upon activation of T lymphocytes expressing the gamma delta T cell receptor (TcR), and that only mouse strains which accumulate gamma delta T cells in the myocardium show apoptosis of myocytes or evidence of dilated cardiomyopathy-like disease. The objective of the present studies is to demonstrate that gamma delta T cells directly induce greater Fas-dependent apoptosis of cultured myocytes than T cells expressing the alpha beta TcR.', 'Bl.Tg.E alpha mice were infected for 7 days with coxsackievirus B3 (CVB3). Hearts were removed and were either formalin-fixed, sectioned and stained with hematoxylin and eosin for inflammation, and using TdT-TUNEL for apoptosis, or were minced and collagenase digested for isolation of gamma delta+ and alpha beta+ T cells using immunomagnetic bead separation. Neonatal cultures of cardiac myocytes were isolated from mice less than 2 days old by collagenase and pancreatin digestion, and were either untreated or infected with virus. Levels of Fas (CD95) were measured using FITC-conjugated hamster anti-mouse Fas monoclonal antibody and flow cytometry. Susceptibility of myocytes to Fas-dependent killing was measured by 51Cr-release by labeled myocytes incubated for 4 h on either 3T3-mock or 3T3-FasL transfected cell monolayers. Killing by T cells was also measured in a 4 h 51Cr-release assay. Fas-dependent and perforin-dependent cytotoxicity was determined by specific blocking using either Fas-Fc or concanamycin A.', 'Virally infected myocyte cultures showed significantly enhanced Fas expression compared to uninfected cells, with maximal upregulation of Fas occurring 18-24 h after virus infection. Both infected and uninfected myocytes were selectively killed by FasL-transfected 3T3 cells but not by mock control cells. Approximately 38% of CD3+ lymphocytes isolated from the heart express the gamma delta TcR with the remainder expressing the alpha beta TcR. Both gamma delta+ and alpha beta+ T cells lysed myocyte targets. Blocking studies indicate that gamma delta+ T cells induced predominantly Fas-mediated killing, while alpha beta+ cell produced more perforin-mediated death, although these effectors were capable of Fas-dependent killing as well.\Question: Do t cells expressing the gamma delta T cell receptor induce apoptosis in cardiac myocytes?
[EX A]: These studies demonstrate that T cells expressing the gamma delta TcR are more effective mediators of myocyte apoptosis than alpha beta+ T cells in vitro and suggests that these effectors may be primarily responsible for myocardial injury associated with dilated cardiomyopathy-like signs during coxsackievirus B3-induced myocarditis.

[EX Q]: Context: The aim of this study was to evaluate the characteristics of low-energy femoral insufficiency fractures in elderly patients.', 'The study retrospectively evaluated the clinical course of 4 patients with low-energy femoral shaft and subtrochanteric fractures admitted to our department between 2009 and 2011. Three patients had prior long-term alendronate therapy and one had prior glucocorticoid therapy.', 'There were 5 femoral shaft fractures, 2 incomplete shaft fractures, 2 subtrochanteric and 1 intertrochanteric fractures. All femoral shaft fractures had characteristic fracture patterns with thickened lateral cortices at the proximal fragment. Six femurs had excessive medial femoral bowing, which complicated intramedullary nailing. Additional fractures were seen on both femurs of one patient who had been primarily treated with short implants. A bifocal femoral fracture was seen in one femur. Union was achieved in all patients. Two patients were able to walk independently, one with a cane and one with double crutches.\Question: Does femoral insufficiency fractures in the elderly - excessive medial femoral bowing complicate intramedullary nailing?
[EX A]: We suggest the addition of another radiographic pattern of 'excessive medial femoral bowing' in low-energy femoral shaft fractures in elderly patients. This bowing complicates intramedullary nailing. Moreover, these insufficiency fractures should be fixed with long cephalomedullary nails.

[EX Q]: Context: In a previous study, UBiT-100\u2009mg, (Otsuka, Spain), a commercial (13)C-urea breath test omitting citric acid pre-treatment, had a high rate of false-positive results; however, it is possible that UBiT detected low-density 'occult' infection missed by other routine reference tests. We aimed to validate previous results in a new cohort and to rule out the possibility that false-positive UBiT were due to an 'occult' infection missed by reference tests.", "Dyspeptic patients (n = 272) were prospectively enrolled and UBiT was performed, according to the manufacturer's recommendations. Helicobacter pylori infection was determined by combining culture, histology and rapid urease test results. We calculated UBiT sensitivity, specificity, positive and negative predictive values (with 95% CI). In addition, we evaluated 'occult' H. pylori infection using two previously-validated polymerase chain reaction (PCR) methods for urease A (UreA) and 16\u2009S sequences in gastric biopsies. We included 44 patients with a false-positive UBiT, and two control groups of 25 patients each, that were positive and negative for all H. pylori tests.", 'UBiT showed a false-positive rate of 17%, with a specificity of 83%. All the positive controls and 12 of 44 patients (27%) with false-positive UBiT were positive for all two PCR tests; by contrast, none of our negative controls had two positive PCR tests.\Question: Does occult H. pylori infection partially explain 'false-positive ' results of ( 13 ) C-urea breath test?
[EX A]:
UBiT suffers from a high rate of false-positive results and sub-optimal specificity, and the protocol skipping citric acid pre-treatment should be revised; however, low-density 'occult' H. pylori infection that was undetectable by conventional tests accounted for around 25% of the 'false-positive' results.