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Lymphocytic choriomeningitis virus is an underreported cause of miscarriage and neurologic disease. Surveillance remains challenging because of nonspecific symptomatology, inconsistent case reporting, and difficulties with diagnostic testing. We describe a case of acute lymphocytic choriomeningitis virus disease in a person living with HIV in Connecticut, USA, identified by using quantitative reverse transcription PCR.

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BACKGROUND: In June 2019, the Bolivian Ministry of Health reported a cluster of cases of hemorrhagic fever that started in the municipality of Caranavi and expanded to La Paz. The cause of these cases was unknown. METHODS: We obtained samples for next-generation sequencing and virus isolation. Human and rodent specimens were tested by means of virus-specific real-time quantitative reverse-transcriptase-polymerase-chain-reaction assays, next-generation sequencing, and virus isolation. RESULTS: Nine cases of hemorrhagic fever were identified; four of the patients with this illness died. The etiologic agent was identified as Mammarenavirus Chapare mammarenavirus, or Chapare virus (CHAPV), which causes Chapare hemorrhagic fever (CHHF). Probable nosocomial transmission among health care workers was identified. Some patients with CHHF had neurologic manifestations, and those who survived had a prolonged recovery period. CHAPV RNA was detected in a variety of human body fluids (including blood; urine; nasopharyngeal, oropharyngeal, and bronchoalveolar-lavage fluid; conjunctiva; and semen) and in specimens obtained from captured small-eared pygmy rice rats (Oligoryzomys microtis). In survivors of CHHF, viral RNA was detected up to 170 days after symptom onset; CHAPV was isolated from a semen sample obtained 86 days after symptom onset. CONCLUSIONS: M. Chapare mammarenavirus was identified as the etiologic agent of CHHF. Both spillover from a zoonotic reservoir and possible person-to-person transmission were identified. This virus was detected in a rodent species, O. microtis. (Funded by the Bolivian Ministry of Health and others.).

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BACKGROUND: Temporary sympathectomy by injection of bupivacaine at the site of the left stellate ganglion is used in the management of refractory angina at several UK centres. Although patients frequently report significant reduction in symptoms, efficacy has not been established by double-blind, randomised placebo-controlled trial (RCT). OBJECTIVE: To investigate the efficacy of the procedure for the first time by a double-blind RCT. METHODS: Consecutive patients referred to the authors' National Health Service (NHS) angina centre who were candidates for temporary sympathectomy were invited to participate in a trial. A total of 65 patients were randomised to receive either bupivacaine or saline injections. Identical syringes were prepared remotely, blinding patients and staff from randomisation. Cardiac autonomic function was measured 3 hours pre- and post-injection using new heart rate variability (HRV) analyses. Angina episodes were recorded contemporaneously by patients in study diaries in the 7-day periods pre- and post-injection. RESULTS: In 51 patients suitable for analysis, no significant differences between the active and placebo groups were found in patient-recorded frequency or intensity of angina episodes pre- and post-injection. However, across both groups combined, a significant difference was found in the frequency of angina episodes pre- and post-injection. CONCLUSION: The reduction in frequency of angina episodes produced by this procedure may not be due to drug pharmacology. It may be a placebo response or due to the mechanical effects of the injection of fluid. There is a need for further work using a larger patient cohort considering both mechanical and psychological factors.

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Pain related to cardiac disease has been recognised for centuries. However, the precise mechanisms of angina pectoris remain bafflingly obscure. Conventional cardiological angina management concentrates on methods to improve oxygen delivery to cardiac myocytes as our understanding of cardiac muscle cells' response to hypoxia increases. In common with other chronic visceral pain syndromes, little is understood about how pain signals are generated and propagated by visceral nerves. Improved imaging and other physiological assessments have demonstrated important central nervous system (CNS) responses to myocardial ischaemia, including activation of CNS areas known to be 'key players' in chronic pain syndromes. Patients with stable angina usually have an excellent prognosis, especially if left ventricular function is preserved. Educating patients about their condition, teaching simple techniques known to help chronic pain patients and introducing targeted pain treatments specific to angina can be extremely helpful adjuncts to conventional cardiological treatments and will often bring about significant improvements in quality of life.

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Previous atomistic simulations and experiments have attributed size effects in the elastic modulus of Ag nanowires to surface energy effects inherent to metallic surfaces. However, differences in experimental and computational trends analyzed here imply that other factors are controlling experimentally observed modulus changes. This study utilizes atomistic simulations to determine how strongly nanowire geometry and surface structure influence nanowire elastic modulus. The results demonstrate that although these factors do influence the elastic modulus of Ag nanowires to some extent, they alone are insufficient to explain current experimental trends in nanowire modulus with decreasing dimensional scale. Future work needs to be done to determine whether other factors, such as surface contaminants or oxide layers, contribute to the experimentally observed elastic modulus increase.

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Dislocation nucleation is essential to the plastic deformation of small-volume crystalline solids. The free surface may act as an effective source of dislocations to initiate and sustain plastic flow, in conjunction with bulk sources. Here, we develop an atomistic modeling framework to address the probabilistic nature of surface dislocation nucleation. We show the activation volume associated with surface dislocation nucleation is characteristically in the range of 1-10b3, where b is the Burgers vector. Such small activation volume leads to sensitive temperature and strain-rate dependence of the nucleation stress, providing an upper bound to the size-strength relation in nanopillar compression experiments.

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Chronic refractory angina is an increasingly prevalent, complex chronic pain condition, which results in frequent hospitalization for chest pain. We have previously shown that a novel outpatient cognitive-behavioral chronic disease management program (CB-CDMP) improves angina status and quality of life in such patients. In the present study of 271 chronic refractory angina patients enrolled in our CB-CDMP, total hospital admissions were reduced from 2.40 admissions per patient per year to 1.78 admissions per patient per year (P<0.001). The rising trend of total hospital bed day occupancy prior to enrollment fell from 15.48 days per patient per year to a stable 10.34 days per patient per year (P<0.001). There were 32 recorded myocardial infarctions prior to enrollment compared to eight in the year following enrollment (14% vs. 2.3%, P<0.001) and overall mortality was lower that comparable groups treated with surgery. This study shows that educating patients and demystifying angina using a brief outpatient CB-CDMP produces an immediate and sustained reduction in hospital admission costs that represents a major potential health care saving. This benefit accrues in addition to the known effects of CB-CDMP on symptoms and quality of life. These data suggest that a CB-CDMP approach to symptom palliation represents a low cost alternative to palliative revascularization.

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The aim of this study was to investigate the safety and efficacy of the two most commonly practiced temporary sympathectomy techniques in the treatment of chronic refractory angina. Fifty-nine consecutive refractory angina patients commencing outpatient temporary sympathectomy from November 1, 2000 to November 1, 2002, were prospectively audited for duration of pain relief and procedural complications over a two-year period. A total of 227 stellate ganglion blockades (SGB) and 100 paravertebral blockades (PVB) were performed on 59 chronic refractory angina (CRA) patients naïve to sympathectomy. The mean period of pain relief obtained following SGB was 3.48 weeks (SD 3.38) and the mean relief following PVB was 2.80 weeks (SD 2.00). Mild, fully reversible complications occurred in 3% of SGB and 3% of PVB procedures, with one patient requiring overnight hospitalization. This study demonstrates that temporary sympathectomy may provide a safe and effective outpatient procedure in refractory angina patients when applied as part of holistic care.

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Angina pectoris that is refractory to optimal medication and revascularization is becoming an increasingly common clinical problem. Recently the US Food and Drug Administration (FDA) approved transmyocardial laser revascularization (TMLR) for use in this group of patients and a large numbers of patients have already undergone this therapy. Unfortunately TMLR has is associated with an unacceptably high perioperative mortality (Cooley DA, Frazier OH, Kadipasaoglu KA, Lindenmeir MH, Pehlivanoglu S, KoIff JW, Wilansky S, Moore WH. Transmyocardiai laser revascularisation: clinical experience with twelve-month follow-up. J Thorac Cardiovasc Surg 1996;111:791-799; Horvath KA, Cohn LH, Cooley DA, Crew JR, Frazier GH, Griffith BP, Kadipasaoglu K, Lansing A, Mannting F, March R, Mirhoseini MR, Smith C. Transmyocardial laser revascularisation: results of a multi-centre transmyocardial laser revascularisation used as sole therapy for end-stage coronary artery disease. J Thorac Cardiovasc Surg 1997;113:645-654; Schofield PM, Sharples LD, Caine N, Burns S, Tait S, Wistow T, Buxton M, Wallwork J. Transmyocardial laser revascularisation in patients with refractory angina: a randomised controlled trial. Lancet 1999;353:519-524), and recurrent refractory angina is common (Allen KB, Dowling RD, Fudge TL, Schoettle GP, Selinger SL, Gangahar OM, Angell WW, Petracek MR, Shaar CJ, O'Neill WW. Comparison of transmyocardial revascularization with medical therapy in patients with refractory angina. N Engl J Med 1999;341:1021-1028; Frazier OH, March RJ, Horvath KA, for the Transmyocardial Carbon Dioxide Laser Revascularization Study Group. Transmyocardial revascularization with a carbon dioxide laser in patients with end-stage coronary artery disease. N Engl J Med 1999;341:1021-1028). Temporary sympathectomy by stellate ganglion block (SGB) is in widespread use in a variety of chronic pain conditions and has long history of use in the management of angina (Moore DC. Stellate ganglion block. Springfield, IL: CC Thomas, 1954; Wiener L, Cox JW. Influence of stellate ganglion blockade on angina pectoris and the post exercise electrocardiogram. Am J Med Sci 1966;252:289-295). Here we describe a patient with end stage coronary artery disease and chronic refractory angina whose has been successfully treated with repeated unilateral left SGBs following multiple bypass operations, angioplasty procedures and laser therapy. This case report details his progress over a 34 month follow-up period.

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