A repeating fast radio burst associated with a persistent radio source.

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately [Formula: see text] parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.

A repeating fast radio burst source in a globular cluster.

Fast radio bursts (FRBs) are flashes of unknown physical origin1. The majority of FRBs have been seen only once, although some are known to generate multiple flashes2,3. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission4,5. Recently, the discovery6 of another repeater (FRB 20200120E) was announced, in the direction of the nearby galaxy M81, with four potential counterparts at other wavelengths6. Here we report observations that localized the FRB to a globular cluster associated with M81, where it is 2 parsecs away from the optical centre of the cluster. Globular clusters host old stellar populations, challenging FRB models that invoke young magnetars formed in a core-collapse supernova. We propose instead that FRB 20200120E originates from a highly magnetized neutron star formed either through the accretion-induced collapse of a white dwarf, or the merger of compact stars in a binary system7. Compact binaries are efficiently formed inside globular clusters, so a model invoking them could also be responsible for the observed bursts.

A repeating fast radio burst source localized to a nearby spiral galaxy.

Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes1,2. Their physical origin remains unknown, but dozens of possible models have been postulated3. Some FRB sources exhibit repeat bursts4-7. Although over a hundred FRB sources have been discovered8, only four have been localized and associated with a host galaxy9-12, and just one of these four is known to emit repeating FRBs9. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source6, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure6 further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.

An extreme magneto-ionic environment associated with the fast radio burst source FRB 121102.

Fast radio bursts are millisecond-duration, extragalactic radio flashes of unknown physical origin. The only known repeating fast radio burst source-FRB 121102-has been localized to a star-forming region in a dwarf galaxy at redshift 0.193 and is spatially coincident with a compact, persistent radio source. The origin of the bursts, the nature of the persistent source and the properties of the local environment are still unclear. Here we report observations of FRB 121102 that show almost 100 per cent linearly polarized emission at a very high and variable Faraday rotation measure in the source frame (varying from +1.46 × 105 radians per square metre to +1.33 × 105 radians per square metre at epochs separated by seven months) and narrow (below 30 microseconds) temporal structure. The large and variable rotation measure demonstrates that FRB 121102 is in an extreme and dynamic magneto-ionic environment, and the short durations of the bursts suggest a neutron star origin. Such large rotation measures have hitherto been observed only in the vicinities of massive black holes (larger than about 10,000 solar masses). Indeed, the properties of the persistent radio source are compatible with those of a low-luminosity, accreting massive black hole. The bursts may therefore come from a neutron star in such an environment or could be explained by other models, such as a highly magnetized wind nebula or supernova remnant surrounding a young neutron star.

A direct localization of a fast radio burst and its host.

Fast radio bursts are astronomical radio flashes of unknown physical nature with durations of milliseconds. Their dispersive arrival times suggest an extragalactic origin and imply radio luminosities that are orders of magnitude larger than those of all known short-duration radio transients. So far all fast radio bursts have been detected with large single-dish telescopes with arcminute localizations, and attempts to identify their counterparts (source or host galaxy) have relied on the contemporaneous variability of field sources or the presence of peculiar field stars or galaxies. These attempts have not resulted in an unambiguous association with a host or multi-wavelength counterpart. Here we report the subarcsecond localization of the fast radio burst FRB 121102, the only known repeating burst source, using high-time-resolution radio interferometric observations that directly image the bursts. Our precise localization reveals that FRB 121102 originates within 100 milliarcseconds of a faint 180-microJansky persistent radio source with a continuum spectrum that is consistent with non-thermal emission, and a faint (twenty-fifth magnitude) optical counterpart. The flux density of the persistent radio source varies by around ten per cent on day timescales, and very long baseline radio interferometry yields an angular size of less than 1.7 milliarcseconds. Our observations are inconsistent with the fast radio burst having a Galactic origin or its source being located within a prominent star-forming galaxy. Instead, the source appears to be co-located with a low-luminosity active galactic nucleus or a previously unknown type of extragalactic source. Localization and identification of a host or counterpart has been essential to understanding the origins and physics of other kinds of transient events, including gamma-ray bursts and tidal disruption events. However, if other fast radio bursts have similarly faint radio and optical counterparts, our findings imply that direct subarcsecond localizations may be the only way to provide reliable associations.

Development of a prediction score (ThyroCOVID) for identifying abnormal thyroid function in COVID-19 patients.

PURPOSE: Thyroid dysfunction in COVID-19 carries clinical and prognostic implications. In this study, we developed a prediction score (ThyroCOVID) for abnormal thyroid function (TFT) on admission amongst COVID-19 patients. METHODS: Consecutive COVID-19 patients admitted to Queen Mary Hospital were prospectively recruited during July 2020-May 2021. Thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were measured on admission. Multivariable logistic regression analysis was performed to identify independent determinants of abnormal TFTs. ThyroCOVID was developed based on a clinical model with the lowest Akaike information criteria. RESULTS: Five hundred and forty six COVID-19 patients were recruited (median age 50 years, 45.4% men, 72.9% mild disease on admission). 84 patients (15.4%) had abnormal TFTs on admission. Patients with abnormal TFTs were more likely to be older, have more comorbidities, symptomatic, have worse COVID-19 severity, higher SARS-CoV-2 viral loads and more adverse profile of acute-phase reactants, haematological and biochemical parameters. ThyroCOVID consisted of five parameters: symptoms (malaise), comorbidities (ischaemic heart disease/congestive heart failure) and laboratory parameters (lymphocyte count, C-reactive protein, and SARS-CoV-2 cycle threshold values). It was able to identify abnormal TFT on admission with an AUROC of 0.73 (95% CI 0.67-0.79). The optimal cut-off of 0.15 had a sensitivity of 75.0%, specificity of 65.2%, negative predictive value of 93.5% and positive predictive value of 28.1% in identifying abnormal TFTs on admission amongst COVID-19 patients. CONCLUSION: ThyroCOVID, a prediction score to identify COVID-19 patients at risk of having abnormal TFT on admission, was developed based on a cohort of predominantly non-severe COVID-19 patients.

Update on the Recommendations on Breast Cancer Screening by the Cancer Expert Working Group on Cancer Prevention and Screening.

Breast cancer (BC) is the most common cancer among women in Hong Kong. The Food and Health Bureau commissioned The University of Hong Kong (HKU) to conduct the Hong Kong Breast Cancer Study (HKBCS) with the aim of identifying relevant risk factors for BC in Hong Kong and developing a locally validated BC risk assessment tool for Hong Kong Chinese women. After consideration of the most recent international and local scientific evidence including findings of the HKBCS, the Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) has reviewed and updated its BC screening recommendations. Existing recommendations were preserved for women at high risk and slightly changed for women at moderate risk. The following major updates have been made concerning recommendations for other women in the general population: Women aged 44 to 69 with certain combinations of personalised risk factors (including presence of history of BC among first-degree relative, a prior diagnosis of benign breast disease, nulliparity and late age of first live birth, early age of menarche, high body mass index and physical inactivity) putting them at increased risk of BC are recommended to consider mammography screening every 2 years. They should discuss with their doctors on the potential benefits and harms before undergoing mammography screening. A risk assessment tool for local women (eg, one developed by HKU) is recommended to be used for estimating the risk of developing BC with regard to the personalised risk factors described above.

Predictors of Post-operative Pain and Opioid Consumption in Patients Undergoing Liver Surgery.

BACKGROUND: Post-operative pain management is a critical component of perioperative care. Patients at risk of poorly controlled post-operative pain may benefit from early measures to optimize pain management. We sought to identify risk factors for post-operative pain and opioid consumption in patients undergoing liver resection. METHODS: This is a multi-institutional prospective nested cohort study of patients undergoing open liver resection. Opioid consumption and pain scores were collected following surgery. To estimate the effects of patient factors on opioid consumption (oral morphine equivalents-OME) and on pain scores (NRS-11), we used generalized linear models and multivariable linear regression model, respectively. RESULTS: One hundred and fifty-three patients who underwent open liver resection between 2013 and 2016 were included in the study. The mean patient age was 62.2 years, and 43.3% were female. Younger patients were significantly more likely to use more opioids in the early post-operative period (16.7 OME/10 years, p < 0.001). Patient factors that were significantly associated with increased NRS-11 pain scores also included younger patient age (difference in pain score of 0.3/10 years with cough and 0.2/10 years at rest, p < 0.01 for both) as well as a history of analgesic use (difference in pain score of 0.9 with cough and 0.6 at rest, p < 0.01 and p = 0.07, respectively). CONCLUSION: Younger patients and those with a history of analgesic use are more likely to report higher post-operative pain and require higher doses of opioids. Early identification of these patients, and measures to better manage their pain, may contribute to optimal perioperative care.

Experience and psychological impact of anal cancer screening in gay, bisexual and other men who have sex with men: a qualitative study.

OBJECTIVE: Human papillomavirus-related anal cancer rates are increasing and are particularly high in gay, bisexual and other men who have sex with men (GBM/MSM), especially HIV-positive individuals. Although screening programs for high-risk populations have been advocated, concerns about possible adverse psychological consequences exist. This study aimed to investigate GBM/MSM's experience, understanding and emotional response to screening techniques for anal cancer to determine how best to minimise psychological distress in future programs. METHODS: In-depth qualitative face-to-face interviews were conducted with 21 GBM/MSM participating in the "Study of the Prevention of Anal Cancer" in Sydney, Australia, between June 2013 and June 2014. Nonrandom, purposive sampling was used to ensure heterogeneity with respect to HIV status and screening test results. Framework analysis method was used to organise the data and identify emerging themes. RESULTS: Knowledge about anal cancer, human papillomavirus and the link between them was limited. Abnormal screening results affected participants' sense of well-being and were associated with anxiety and concern about developing anal cancer. HIV-negative men receiving abnormal results showed higher levels of distress compared to their HIV-positive counterparts. Consultations with general practitioners about abnormal results had an important role in increasing participants' understanding and in moderating their anxiety. CONCLUSION: Anal cancer screening should be accompanied by health education around anal cancer, its aetiology and the meaning of associated test results. Simple and effective communication strategies should be encouraged. Collaboration with general practitioners could assist the process of education and reporting test results.

Recommendations on prevention and screening for colorectal cancer in Hong Kong.

Colorectal cancer is the commonest cancer in Hong Kong. The Cancer Expert Working Group on Cancer Prevention and Screening was established in 2002 under the Cancer Coordinating Committee to review local and international scientific evidence, assess and formulate local recommendations on cancer prevention and screening. At present, the Cancer Expert Working Group recommends that average-risk individuals aged 50 to 75 years and without significant family history consult their doctors to consider screening by: (1) annual or biennial faecal occult blood test, (2) sigmoidoscopy every 5 years, or (3) colonoscopy every 10 years. Increased-risk individuals with significant family history such as those with a first-degree relative diagnosed with colorectal cancer at age ≤60 years; those who have more than one first-degree relative diagnosed with colorectal cancer irrespective of age at diagnosis; or carriers of genetic mutations associated with familial adenomatous polyposis or Lynch syndrome should start colonoscopy screening earlier in life and repeat it at shorter intervals.

Recommendations on prevention and screening for breast cancer in Hong Kong.

In Hong Kong, breast cancer is the most common cancer among women and poses a significant health care burden. The Cancer Expert Working Group on Cancer Prevention and Screening (CEWG) was set up in 2002 by the Cancer Coordinating Committee to review and assess local and international scientific evidence, and to formulate recommendations for cancer prevention and screening. After considering the local epidemiology, emerging scientific evidence, and local and overseas screening practices, the CEWG concluded that it was unclear whether population-based breast cancer screening did more harm than good in local asymptomatic women at average risk. The CEWG considers that there is insufficient evidence to recommend for or against population-based mammography screening for such individuals. Women who consider breast cancer screening should be adequately informed about the benefits and harms. The CEWG recommends that all women adopt primary preventive measures, be breast aware, and seek timely medical attention for suspicious symptoms. For women at high risk of breast cancer, such as carriers of confirmed BRCA1/2 deleterious mutations and those with a family history of breast cancer, the CEWG recommends that they seek doctor's advice for annual mammography screening and the age at which the process should commence. Additional annual screening by magnetic resonance imaging is recommended for confirmed BRCA1/2 mutation carriers or women who have undergone radiation therapy to the chest between the age of 10 and 30 years. Women at moderate risk of breast cancer should discuss with doctors the pros and cons of breast cancer screening before making an informed decision about mammography screening every 2 to 3 years.

Genetic basis of channelopathies and cardiomyopathies in Hong Kong Chinese patients: a 10-year regional laboratory experience.

INTRODUCTION: Hereditary channelopathies and cardiomyopathies are potentially lethal and are clinically and genetically heterogeneous, involving at least 90 genes. Genetic testing can provide an accurate diagnosis, guide treatment, and enable cascade screening. The genetic basis among the Hong Kong Chinese population is largely unknown. We aimed to report on 28 unrelated patients with positive genetic findings detected from January 2006 to December 2015. METHODS: Sanger sequencing was performed for 28 unrelated patients with a clinical diagnosis of channelopathies or cardiomyopathies, testing for the following genes: KCNQ1,KCNH2,KCNE1,KCNE2, and SCN5A, for long QT syndrome; SCN5A for Brugada syndrome; RYR2 for catecholaminergic polymorphic ventricular tachycardia; MYH7 and MYBPC3 for hypertrophic cardiomyopathy; LMNA for dilated cardiomyopathy; and PKP2 and DSP for arrhythmogenic right ventricular dysplasia/cardiomyopathy. RESULTS: There were 17 males and 11 females; their mean age at diagnosis was 39 years (range, 1-80 years). The major clinical presentations included syncope, palpitations, and abnormal electrocardiography findings. A family history was present in 13 (46%) patients. There were 26 different heterozygous mutations detected, of which six were novel-two in SCN5A (NM_198056.2:c.429del and c.2024-11T>A), two in MYBPC3 (NM_000256.3:c.906-22G>A and c.2105_2106del), and two in LMNA (NM_170707.3:c.73C>A and c.1209_1213dup). CONCLUSIONS: We have characterised the genetic heterogeneity in channelopathies and cardiomyopathies among Hong Kong Chinese patients in a 10-year case series. Correct interpretation of genetic findings is difficult and requires expertise and experience. Caution regarding issues of non-penetrance, variable expressivity, phenotype-genotype correlation, susceptibility risk, and digenic inheritance is necessary for genetic counselling and cascade screening.

Patterns and Drivers of Costs for Neuroendocrine Tumor Care: A Comparative Population-Based Analysis.

BACKGROUND: Little is known about resource use in the care of neuroendocrine tumors (NETs). This study defined patterns of costs in NET management and compared them with those of a more common malignancy, colon cancer (CC). METHODS: Using a provincial cancer registry (2004-2012), NET patients were identified and matched at a ratio of 1-3 with CC patients. Four phases of care were examined: pre-diagnostic (PreDx: -2 years to -181 days), diagnostic (Dx: -180 days to +180 days), postdiagnostic (PostDx: +181 days to +3 years), and prolonged post-diagnostic (PPostDx: +181 days to +9 years). The mean costs per patient were compared, and cost predictors were analyzed with quintile regression. RESULTS: Of 3827 NETs, 3355 were matched with 9320 CCs. The PreDx mean NET costs were higher than the CC costs ($5877 vs $5368; p = 0.06), driven by nondrug costs. They were lower in the Dx and PostDx phases (both p < 0.01). For PPostDx, the drug costs were higher for NETs ($26,788 vs $7827; p < 0.01), representing 41% of the costs versus 16% of the costs for CC. Older age and comorbidities predicted higher NET costs in all phases. Lower socioeconomic status (SES) predicted higher costs in the initial phases and higher SES costs in the PPost-Dx phase. Gastroenteric NETs were associated with lower costs in the Dx phase [parameter estimate (PE), -$13,644] and pancreatic NETs with higher costs in PostDx phase (PE, $3348). CONCLUSION: Currently, NETs represent a potential important health care burden. The NET cost patterns differed from those for CC, with the highest costs during the PPostDx phase. The SES and primary NET site affected costs differently at different time points. These data can inform resource allocation tailored to the needs for NETs.

A qualitative study of the impact of endometriosis on male partners.

STUDY QUESTION: What is the impact of endometriosis on male partners of women with the condition? SUMMARY ANSWER: Endometriosis significantly impacts men across several life domains and can negatively impact emotional well-being. WHAT IS KNOWN ALREADY: Endometriosis has been shown to negatively impact women's quality of life and may strain intimate relationships. Little is known about the impact on male partners. STUDY DESIGN, SIZE, DURATION: The ENDOPART study was a cross-sectional, qualitative study of 22 women with endometriosis and their male partners (n = 44) in the UK (2012-2013). PARTICIPANTS/MATERIALS, SETTING, METHODS: Inclusion criteria: laparoscopic diagnosis of endometriosis; the presence of symptoms for at least a year; partners living together. Data were collected via face to face, semi structured interviews with partners interviewed separately. Data were analysed thematically, assisted by NVivo 10. MAIN RESULTS AND THE ROLE OF CHANCE: Men reported that endometriosis affected many life domains including sex and intimacy, planning for and having children, working lives and household income. It also required them to take on additional support tasks and roles. Endometriosis also had an impact on men's emotions, with responses including helplessness, frustration, worry and anger. The absence of professional or wider societal recognition of the impact on male partners, and a lack of support available to men, results in male partners having a marginalized status in endometriosis care. LIMITATIONS REASONS FOR CAUTION: Self-selection of participants may have resulted in a sample representing those with more severe symptoms. Couples included are in effect 'survivors' in relationship terms, therefore, findings may underestimate the contribution of endometriosis to relationship breakdown. WIDER IMPLICATIONS OF THE FINDINGS: The study extends knowledge about the impact of endometriosis on relationships, which thus far has been drawn largely from studies with women, by providing new insights about how this condition affects male partners. Healthcare practitioners need to take a more couple-centred, biopsychosocial approach toward the treatment of endometriosis, inclusive of partners and relationship issues. The findings demonstrate a need for information and support resources aimed at partners and couples. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the Economic and Social Research Council (reference ES/J003662/1). The authors have no conflicts of interest.

Three-point transfusion risk score in hepatectomy.

BACKGROUND: Perioperative red blood cell transfusions are required in up to 23 per cent of patients undergoing hepatectomy. Previous research has developed three transfusion risk scores to assess risk of perioperative red blood cell transfusion. Here, the performance of these transfusion risk scores was evaluated in a multicentre cohort of patients who underwent hepatectomy and compared with that of a simplified transfusion risk score. METHODS: A database of patients undergoing hepatectomy at four specialized centres between 2008 and 2012 was developed. External validity was assessed by discrimination and calibration. Discrimination was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC). Calibration was evaluated by the degree of agreement between predicted and actual red blood cell transfusion probabilities. A simplified transfusion risk score using variables common to the three models was created, and discrimination and calibration were evaluated. RESULTS: There were 1287 patients included in this study, with 341 (26·5 per cent) receiving a red blood cell transfusion. Discriminative ability was similar between the three transfusion risk scores, with AUCs of 0·66-0·68 and good calibration. A new three-point risk score was developed based on factors present in all models: haemoglobin 12·5 g/dl or less, primary liver malignancy and major resection (at least 4 segments). Discriminative ability and calibration of the three-point model were similar to those of the three existing models, with an AUC of 0·66. CONCLUSION: The three-point transfusion risk score simplifies assessment of perioperative transfusion risk in hepatectomy without sacrificing predictive ability.

Ankyloglossia as a risk factor for maxillary hypoplasia and soft palate elongation: A functional - morphological study.

OBJECTIVES: To characterize associations between restricted tongue mobility and maxillofacial development. SETTING AND SAMPLE POPULATION: Cross-sectional cohort study of 302 consecutive subjects from an orthodontic practice. MATERIAL AND METHODS: Tongue mobility (measured with tongue range of motion ratio [TRMR] and Kotlow free tongue measurement) was correlated with measurements of the maxillofacial skeleton obtained from dental casts and cephalometric radiographs. RESULTS: Tongue range of motion ratio and Kotlow measures of restricted tongue mobility were associated with (i) ratio of maxillary intercanine width to canine arch length, (ii) ratio of maxillary intermolar width to canine arch length and (iii) soft palate length. Restricted tongue mobility was not associated with hyoid bone position or Angle's skeletal classification. CONCLUSIONS: Restricted tongue mobility was associated with narrowing of the maxillary arch and elongation of the soft palate in this study. These findings suggest that variations in tongue mobility may affect maxillofacial development.