Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae.

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Implementation and impact of a post-exposure prophylaxis helpline.

BACKGROUND: Despite a 2007 national and regional training programme, there was poor implementation of a post-exposure prophylaxis (PEP) programme to prevent occupational transmission of HIV in health care workers (HCWs) in Delhi. A new initiative was therefore launched by the Delhi State AIDS Control Society in 2010 to improve uptake of PEP in HCWs. AIMS: To assess the implementation and efficacy of the PEP programme in Delhi. METHODS: The initiative included a PEP poster and a telephone helpline together with a workshop for senior doctors of 46 public hospitals nominated as PEP supervisors. Data concerning use of the PEP help line and number of HCWs enrolling for PEP between January 2011 and May 2014 were analysed. RESULTS: Until September 2010, only 61% (28) of Delhi hospitals had PEP drugs and medical supervisors to manage the programme and reports concerning the programme were not sent. After roll-out of the PEP helpline, 4057 HCWs accessed the helpline, all public hospitals started implementing the programme and sent monthly reports. During the same period, 1450 HCWs suffered from occupational exposures, 15% were started on PEP drugs of who 98% completed the full course of prophylaxis. CONCLUSIONS: The PEP helpline is probably the first in a developing country and has been helpful for the effective implementation of the national PEP programme in Delhi.

Safety and effectiveness of sacroplasty: a large single-center experience.

BACKGROUND AND PURPOSE: Sacral insufficiency fractures are a common cause of severe low back pain and immobilization in patients with osteoporosis or cancer. Current practice guideline recommendations range from analgesia and physical therapy to resection with surgical fixation. We sought to assess the safety and effectiveness of sacroplasty, an emerging minimally invasive treatment. MATERIALS AND METHODS: We performed a retrospective review of institutional databases for percutaneous sacroplasty performed between January 2004 and September 2013. Demographic and procedural data and pre- and posttreatment Visual Analog Scale, Functional Mobility Scale, and Analgesic Scale scores were reviewed. Overall response was rated by using a 4-point scale (1, complete resolution of pain; 2, improvement of pain; 3, no change; 4, worsened pain) assessed at short-term follow-up. RESULTS: Fifty-three patients were included; most (83%) were female. Fracture etiology was cancer-related (55%), osteoporotic insufficiency (30%), and minor trauma (15%). No major complication or procedure-related morbidity occurred. There were statistically significant decreases in the Visual Analog Scale (P < .001), Functional Mobility Scale (P < .001), and Analgesic Scale scores (P < .01) in 27 patients with recorded data: pretreatment Visual Analog Scale (median [interquartile range], 9.0 [8.0-10.0]); Functional Mobility Scale, 3.0 (2.0-3.0); and Analgesic Scale scores, 3.0 (3.0-4.0) were reduced to 3.0 (0.0-5.8), 1.0 (0.25-2.8), and 3.0 (2.0-3.8) posttreatment. When we used the overall 4-point score at a mean of 27 days, 93% (n = 45) reported complete resolution or improvement in overall pain. CONCLUSIONS: In this single-center cohort, sacroplasty was a safe and effective procedure. There were significant short-term gains in pain relief, increased mobility, and decreased dependence on pain medication.

Interobserver reliability of baseline noncontrast CT Alberta Stroke Program Early CT Score for intra-arterial stroke treatment selection.

BACKGROUND AND PURPOSE: Early ischemic changes on pretreatment NCCT quantified using ASPECTS have been demonstrated to predict outcomes after IAT. We sought to determine the interobserver reliability of ASPECTS for patients with AIS with PAO and to determine whether pretreatment ASPECTS dichotomized at 7 would demonstrate at least substantial κ agreement. MATERIALS AND METHODS: From our prospective IAT data base, we identified consecutive patients with anterior circulation PAO who underwent IAT over a 6-year period. Only those with an evaluable pretreatment NCCT were included. ASPECTS was graded independently by 2 experienced readers. Interrater agreement was assessed for total ASPECTS, dichotomized ASPECTS (≤ 7 versus >7), and each ASPECTS region. Statistical analysis included determination of Cohen κ coefficients and concordance correlation coefficients. PABAK coefficients were also calculated. RESULTS: One hundred fifty-five patients met our study criteria. Median pretreatment ASPECTS was 8 (interquartile range 7-9). Interrater agreement for total ASPECTS was substantial (concordance correlation coefficient = 0.77). The mean ASPECTS difference between readers was 0.2 (95% confidence interval, -2.8 to 2.4). For dichotomized ASPECTS, there was a 76.8% (119/155) observed rate of agreement, with a moderate κ = 0.53 (PABAK = 0.54). By region, agreement was worst in the internal capsule and the cortical areas, ranging from fair to moderate. After adjusting for prevalence and bias, agreement improved to substantial or near perfect in most regions. CONCLUSIONS: Interobserver reliability is substantial for total ASPECTS but is only moderate for ASPECTS dichotomized at 7. This may limit the utility of dichotomized ASPECTS for IAT selection.

Peroxisome proliferators-activated receptor γ2 Pro12Ala variant is associated with body mass index in non-alcoholic fatty liver disease patients.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease globally and commonly associated with insulin resistance and metabolic syndrome (MS). Peroxisome proliferator-activated receptor-γ (PPARγ) is a transcription factor abundantly expressed in adipocytes and plays a key role in the regulation of adipocyte differentiation, lipid and glucose homeostasis. Pro12Ala variant has been earlier associated with obesity, type 2 diabetes and MS. AIM: The present study aimed to determine the genotype frequencies of the Pro12Ala variant in NAFLD patients and any further association with other phenotype in the patients. PATIENTS AND METHODS: Ninety-eight NAFLD patients and 280 matched controls were genotyped for presence of the Pro12Ala variant. Genomic DNA was extracted and polymerase chain reaction-restriction fragment length polymorphism using Bst-UI was performed for the detection of C-G change at codon 12 position of PPAR γ2 gene. Genotype and allele frequencies were compared between patients and controls. The Hardy-Weinberg equilibrium was tested by comparing expected/observed genotype frequencies by χ(2) test. RESULTS: The frequencies of Pro/Ala genotype were comparable between NAFLD patients and controls. In the controls, 213 (75.7%) were homozygous for the wild-type (Pro/Pro) genotype and 67 (23.9%) were heterozygous (Pro/Ala). In NAFLD patients, genotypic distribution of wild type, heterozygous and homozygous were 63 (64.3%), 34 (34.7%) and 1 (1%), respectively. Heterozygous genotype was found to be significantly higher in the patients (P = 0.01). We also analyzed related phenotypic association of the patients with Pro12Ala genotype. We observed that the Pro12Ala (heterozygous) genotype was significantly higher in the patients who had body mass index >25 kg/m(2) (P = 0.025). CONCLUSIONS: Pro12Ala variation of the PPAR γ2 gene is associated with NAFLD and might play a role in the pathogenesis of NAFLD.

Intracranial juvenile nasopharyngeal angiofibroma.

Eight cases of intracranial extensions of juvenile nasopharyngeal angiofibromas (JNA) are presented. These form 33% of the cases of JNA treated during a 5-year period (1988-93). A high incidence of visual complications in this stage of tumour is observed and the basis of this is discussed. Death results from serious complications of severe haemorrhage and cerebro-spinal fluid leak. The intradural intracranial extensions of the tumour warrant careful approach in terms of surgery, because of their greater risk for complications during the dissection.

Hearing loss in Papua New Guinea: a study of outpatients attending Port Moresby General Hospital.

Hearing loss, with its cause, type and degree, was studied in patients who attended the Ear, Nose and Throat (ENT) Outpatient Clinic at the Port Moresby General Hospital for a period of 5 years from 1987 to 1992. It was found that 1150 (18%) of the patient population attending the ENT Clinic had hearing loss. Audiological evaluation was performed in 583 patients. More males presented to the clinic with hearing loss than females. Otitis media was the most common identified cause of hearing loss followed by ear trauma and meningitis/cerebral malaria. Assaults were the major cause of traumatic hearing loss. Lack of awareness on the part of both professionals and parents affected early identification of hearing loss, especially in children, whose development of speech and language was seriously impaired. The need for implementation of suitable rehabilitation measures by the health services is emphasized.

Nasal cartilaginous tumour.

A cartilaginous tumour of nasal region in a 6-year-old child is described. The problems of histological interpretation and treatment are discussed.

Comparative in situ hybridisation study of juvenile laryngeal papillomatosis in Papua New Guinea and Australia.

A comparative study of cases of juvenile laryngeal papillomatosis from Papua New Guinea (n = 3) and Brisbane, Australia (n = 9) was carried out. In situ hybridisation reactions for human papillomavirus (HPV) types 6 and 11 occurred in 11 cases. All three cases from Papua New Guinea and eight from Australia gave positive signals. A negative reaction was observed in one Australian case. The intensity of the reaction was strong in seven cases, moderate in one, and weak in three. An equivocal reaction was also noted with probes for types 16 and 18, and types 31, 33, and 35 in two cases from Australia and one from Papua New Guinea. It is concluded that as similar staining patterns and intensities occurred in cases from both areas, the aetiology is the same. The equivocal reactions noted in three cases were probably due to cross hybridisation rather than multiple infection.

An uncommon cause of death from upper respiratory tract obstruction.

The death of a 45-year-old man from obstruction of the inlet of the larynx by a cyst causing acute upper respiratory obstruction is described. The pathological features of the cyst are suggestive of a saccular (laryngeal) cyst.

Unusual type of foreign body in the maxillary sinus.

A broken end of the spear presenting as a foreign body in the nasopharynx and right maxillary sinus in a 19-year-old Papua New Guinean is described. The types of foreign bodies and their mechanisms of introduction into this site are summarized.

Juvenile laryngeal papillomatosis: report of five cases from Papua New Guinea.

Five cases of juvenile laryngeal papillomatosis encountered in Papua New Guinea during the period from December 1987 to May 1989 are described in detail. They were seen in the age-range of 1 year 7 months-5 years. The common clinical features were change of voice and dyspnoea. They were treated by microlaryngoscopic excision with cupped forceps. One of the cases followed-up for 15 months showed multiple recurrences. This condition of juvenile laryngeal papillomatosis, though not common, is certainly not rare in this country and should be considered as a differential diagnosis in the case of a child presenting with progressive dyspnoea.