bluuebunny/crossref_metadata_2025 huggingface dataset:
Persistent Infection of Mouse Fibroblasts (L Cells) with
Chlamydia psittaci
: Evidence for a Cryptic Chlamydial Form
Authors: Moulder James W. , Levy Nancy J. , Schulman Laura P.
Published: June 2021

When monolayers of mouse fibroblasts (L cells) were infected with enough
Chlamydia psittaci
(strain 6BC) to destroy most of the host cells, 1 in every 10
5
to 10
6
originally infected cells gave rise to a colony of L cells persistently infected with strain 6BC. In these populations, the density of L cells and 6BC fluctuated periodically and reciprocally as periods of host cell increase were followed by periods of parasite multiplication. Successive cycles of L-cell and 6BC reproduction were sustained indefinitely by periodic transfer to fresh medium. Isolation of L cells and 6BC from persistent infections provided no evidence that there had been any selection of variants better suited for coexistence. Persistently infected populations consisting mainly of inclusion-free L cells yielded only persistently infected clones, grew more slowly, and cloned less efficiently. They were also almost completely resistant to superinfection with high multiplicities of either 6BC or the lymphogranuloma venereum strain 440L of
Chlamydia trachomatis
. These properties of persistently infected L cells may be accounted for by assuming that all of the individuals in these populations are cryptically infected with 6BC and that cryptic infection slows the growth of the host cell and makes it immune to infection with exogenous chlamydiae. According to this hypothesis, the fluctuations in host and parasite density occur because some factor periodically sets off the conversion of cryptic chlamydial forms into reticulate bodies that multiply and differentiate into infectious elementary bodies in a conventional chlamydial developmental cycle.
Translocation of Escherichia coli from the gastrointestinal tract to the mesenteric lymph nodes in gnotobiotic mice receiving Escherichia coli vaccines before colonization
Authors: Berg R D , Garlington A W
Published: June 2021

Germfree mice were immunized orally or intraperitoneally for 6 weeks with heat-killed vaccines of indigenous Escherichia coli or nonindigenous E. coli O 127: B8 before colonization with these strains. The mice exhibited increases in specific serum antibodies and intestinal immunoglobulin A reacting with the E coli antigens. Prior immunization did not reduce the gastrointestinal population levels of the E. coli strains attained 3 and 7 days after colonization. Neither oral nor intraperitoneal immunization with the E. coli strains before colonization decreased the incidence of bacterial translocation to the mesenteric lymph nodes or reduced the number of viable E. coli cells per mesenteric lymph node. There also was no relation in individual mice between serum antibody titers and the numbers of viable E. coli cells translocating to the mesenteric lymph nodes. Thus, prior vaccination with E. coli in this study did not decrease the incidence or reduce the numbers of viable E. coli translocating to the mesenteric lymph nodes in gnotobiotic mice monoassociated with E. coli.
Rapid diagnosis of gram-negative bacterial meningitis by the Limulus endotoxin assay
Authors: Jorgensen J H , Lee J C
Published: June 2021

The Limulus amoebocyte lysate endotoxin assay was evaluated as a method for rapid diagnosis of acute bacterial meningitis in a series of 305 patients. The results of Limulus assays on cerebrospinal fluid (CSF) samples from these patients were compared with the results for each patient of routine bacterial cultures and Gram stains. Positive Limulus tests were obtained on initial CSF specimens from 84% of patients with culture-proven bacterial meningitis, including all patients with meningitis due to gram-negative organisms. Initial Gram-stained smears revealed the presence of organisms in 68% of the patients. One patient with pneumococcal meningitis had a weakly positive Limulus assay, whereas patients with meningitis due to other gram-positive organisms, those with aseptic meningitis, or patients without meningitis had negative CSF Limulus tests. The Limulus assay also demonstrated the persistence of endotoxin in the CSF of certain patients during antibiotic therapy, especially patients with Haemophilus influenzae meningitis. The Limulus test proved to be a rapid, reliable indicator of the presence of gram-negative organisms in the CSF of patients suspected of acute bacterial meningitis.
Determination of Corynebacterium diphtheriae toxigenicity by a colorimetric tissue culture assay
Authors: Murphy J R , Bacha P , Teng M
Published: June 2021

Chinese hamster ovary (CHO) cell cultures in microtiter wells are sensitive to growth inhibition and killing by picogram quantities of diphtheria toxin. In the absence of biologically active toxin, the CHO cell culture produces sufficient acidic metabolites to change the phenol red pH indicator from pink to yellow within 56 h. In the presence of 10 pg of toxin per well, growth inhibition can be observed microscopically within 24 h. Diphtheria toxin can be qualitatively assayed from culture supernatants of Corynebacterium diphtheriae or from beta-phage agar plaque plugs. The colorimetric CHO cell assay method for determining toxigenicity allows for the large-scale screening of either diphtheria toxigenicity or antitoxin titration of sera.
Development and Evaluation of an Immunodiffusion Test for Diagnosis of Systemic Zygomycosis (Mucormycosis): Preliminary Report
Authors: Jones Kenneth W. , Kaufman Leo
Published: June 2021

An antigen analysis with filtrate and homogenate precipitinogens of single isolates of the zygomycetes
Absidia corymbifera, Mucor pusillus, Rhizopus arrhizus
, and
Rhizopus oryzae
demonstrated the presence of common antigens among the three genera as well as antigens which permit their differentiation. Selected homogenate antigens were valuable in developing a diagnostic immunodiffusion (ID) test for systemic zygomycosis. When sera from 43 patients with various proven mycoses other than zygomycosis were tested against each of the antigens, none formed precipitin bands identical to those formed by
A. cormybifera, M. pusillus
, and the
Rhizopus
spp. rabbit reference antisera. Sera from 23 normal persons and 25 diabetics did not react with any of the antigens. Homogenate antigens detected antibody in 8 of the 11 sera (73%) from suspected or proven cases of zygomycosis, whereas ID tests with filtrate antigens detected antibody in only 2 of the 11 sera (18%). Of the eight sera that reacted with the homogenate antigens, five only reacted with a specific
Rhizopus
sp. antigen, two only reacted with a specific
M. pusillus
antigen, and one only reacted with a specific
A. corymbifera
antigen. Study results show the ID test with homogenate antigens to be more specific and sensitive than the ID test with filtrate antigens and indicate that the former is a promising technique for diagnosing human zygomycosis.
Bromothymol blue broth: improved medium for detection of Ureaplasma urealyticum (T-strain mycoplasma)
Authors: Robertson J A
Published: June 2021

Bromothymol blue (B) broth for the cultivation, detection, and identification of Ureaplasma urealyticum is described. In this medium, strains Cook and 960 had shorter generation times (60 min or less) and reached higher populations (over 10(8)) than have yet been reported for this species. Furthermore, the indicator changes color before the end of logarithmic growth, and the cultures retain viability for at least 1 day thereafter, greatly simplifying the handling of the organism. When the populations in cultures of these two strains and seven new isolates were determined, growth was detected earlier and proceeded to higher final titers in B broth than in urease test color medium (U-9 broth). The inclusion of antibiotics in B broth for use in clinical laboratories (B/NL broth) made the medium selective, specific, and more sensitive for the isolation of U. urealyticum. Comparison of B/NL broth with genital mycoplasma (GM) agar and U-9 broth for the primary isolation of U. urealyticum was made with 183 urethral swabs. All 70 isolates were detected on B/NL broth, but only 66 and 63 isolates were detected on GM agar and in U-9 broth, respectively. Moreover, the cultures in B/NL broth were pure and at titers that generally showed good correlation with colony counts on GM agar.
Evaluation of three test procedures for identification of Staphylococcus aureus from clinical sources
Authors: Zarzour J Y , Belle E A
Published: June 2021

A total of 520 clinical and environmental isolates of the family Micrococcaceae that fermented glucose anaerobically were tested for their ability to produce coagulase, thermostable nuclease, and deoxyribonuclease. Of these, 450 isolates coagulated rabbit plasma, produced thermostable nuclease, and were identified as Staphylococcus aureus, 447 of which produced a 3+ to 4+ clot. The remaining three isolates produced a 2+ clot, deoxyribonuclease, and thermostable nuclease. It was found that three of the S. aureus isolates failed to produce deoxyribonuclease. A total of 70 isolates which did not coagulate rabbit plasma and which were thermostable nuclease negative were identified as S. epidermidis. Three of them produced deoxyribonuclease. It is suggested that the thermostable nuclease test be performed on all isolates producing a 2+ (or 1+) clot in the coagulase test before identifying them as S. aureus.
Quantitative fluorescent immunoassay of antibodies to, and surface antigens of, Actinomyces viscosus
Authors: Gillis T P , Thompson J J
Published: June 2021

Optimal conditions for a fluorescence immunoassay of antibodies to, and surface antigens of, Actinomyces viscosus ATCC 19246 are described. In the standard fluorescence immunoassay, 10(8) colony-forming units of A. viscosus reacted with an antibody preparation, were washed, and then were treated with an excess of fluorescein-conjugated goat anti-rabbit immunoglobulin G. After another set of washes, fluorescence was determined in a spectofluorometer; in most cases excitation was at 485 nm, with emission measured at 525 nm. These conditions minimized interference from light scatter and stray light. Under appropriate conditions, antibodies to A. viscosus could be readily determined, with the fluorescence of the specific antibody-treated cells more than five times the fluorescence of controls treated with normal rabbit serum. Organisms coated with specific antibody could be detected at levels approaching 10(5) colony-forming units per ml. The standard fluorescence immunoassay procedure was readily adapted to the measurement of either particulate or soluble surface antigens of A. viscosus by competition of the antigen with a fixed amount of antibody in the standard assay system; the competition resulted in an antigen dose-dependent inhibition of fluorescence. The fluorescent immunoassay system thus appears to be a general one that could be applied to other microbial systems as well.
Achromobacter xylosoxidans isolates in Hawaii
Authors: Pien F D , Higa H Y
Published: June 2021

Clinical and bacteriological features of nine cases in which Achromobacter xylosoxidans were isolated in Hawaii are described. Five cases were ear infections mixed with other gram-negative bacteria. Colonial morphology, xylose oxidation, peritrichous flagella staining, and antibiotic susceptibility pattern assisted in separating this bacterium from other nonfermentative, oxidase-positive, gram-negative rods.
Esculin hydrolysis reaction by Escherichia coli
Authors: Miskin A , Edberg S C
Published: June 2021

The literature contains variable reports concerning the hydrolysis of esculin by members of the family Enterobacteriaceae and particularly Escherichia coli. We examined 113 strains of fresh clinical isolates of E. coli and assessed the ability of colonies in a population to hydrolyze esculin with and without preincubation in inducible substrates at 24, 48, and 72 h. The number of strains capable of fermenting salicin, a sugar with a beta-glucoside linkage like esculin, was studied under the same conditions. A strip test that measured the presence of the constitutive glucosidase was also performed with and without preincubation in inducible substrates. No E. coli strain was able to produce constitutive enzyme; preincubation in esculin and salicin resulted in an induction of the beta-glucosidase. The number of colonies able to hydrolyze esculin increased with time. Only those strains preincubated in esculin or salicin were able to produce a positive constitutive strip test. Because the beta-glucosidase of E. coli is inducible, one should employe, when using growth media, a light inoculum obtained by touching the top of a colony with a bacteriological wire and read the reaction between 18 and 24 h, or perform a rapid strip or spot test.
Simplified microscopy for rapid detection of significant bacteriuria in random urine specimens
Authors: Barbin G K , Thorley J D , Reinarz J A
Published: June 2021

Simplified urine microscopy, nitrite testing, and dipstick culture were compared with urine loop streak culture colony counts in 219 random voided specimens to determine the accuracy of the three rapid screening techniques. Nitrite testing resulted in 65% false negative results, which could not be significantly improved by incubation at 37 degrees C but which could be improved by adding nitrate substrate before incubation. Dipstick culture could not be quantitated until after 18 h of incubation. A new, simplified microscopy technique, using unspun, unstained urine, resulted in 4% false negative results and 4% false positive results in specimens containing over 10(5) organisms per ml and was the best method Centrifuges, Gram staining reagents, and counting chambers are not necessary for accurate microscopic screening of random urine specimens for the presence of bacteriuria by this technique, and the results are immediately available.
Bacteriocin typing of Clostridium perfringens in human feces
Authors: Mahony D E , Swantee C A
Published: June 2021

Three hundred and ninety-nine isolates of Clostridium perfringens from enriched stool specimens of 51 individuals (about eight colonies per person) were typed by bacteriocins. Forty-nine percent of these persons carried more than one bacteriocin type in their stool, and some had three or four different stains as determined by bacteriocin typing. Weekly stool specimens obtained from seven positive volunteers over a period of 5 weeks were screened for C. perfringens, and several colonies from each person were typed. This survey demonstrated that the number of types fluctuated with time, several types could be carried simultaneously, and the isolation of the organism was variable. Nine new bacteriocin types of C. perfringens were isolated in this study.
Quantitative estimation of infantile gastroenteritis virus antigens in stools by immune adherence hemagglutination test
Authors: Matsuno S , Nagayoshi S
Published: June 2021

Infantile gastroenteritis virus antigens in stools were titrated by the immune adherence hemagglutination test. A good correlation was observed between immune adherence hemagglutination titers and electron microscope counts.
Method for Rapid Detection of Group B Streptococci by Coagglutination
Authors: Leland Diane S. , Lachapelle Rene C. , Wlodarski Frederick M.
Published: June 2021

A quick and reliable technique for the identification of group B streptococci has been developed. The method requires no elaborate equipment or expensive reagents and can be used to detect the group B organisms in mixed broth cultures or to identify suspect colonies selected from agar plates. The method is a coagglutination technique in which 1 drop of specifically sensitized protein A-containing
Staphylococcus aureus
is mixed with 1 drop of supernatant of an actively growing culture. The soluble group-specific carbohydrate substance of the group B streptococci reacts with the staph particles to produce agglutination that is macroscopically readable. One colony of group B streptococci taken from an agar plate and inoculated into Todd-Hewitt broth will give a positive reaction within 6 h of incubation; with a larger inoculum, the positive reaction occurs within a shorter period. The method was applied for detection of group B streptococci in mixed broth cultures. In laboratory studies involving random mixtures of organisms, 59.3% of positive cultures were detected within the first 8 h of incubation, and 71.7% were found within 24 h. In clinical studies with mixed broth cultures grown directly from vaginal swabs, 78.6% of the positive cultures were detected within the first 8 h of incubation, and 92.9% were found within 24 h.
Detection of Clostridium perfringens enterotoxin in human fecal samples and anti-enterotoxin in sera
Authors: Naik H S , Duncan C L
Published: June 2021

By using counterimmunoelectrophoresis (CIEP), Clostridium perfringens enterotoxin was successfully demonstrated in fecal samples collected within 1 day of attack from sick individuals involved in a bacteriologically and epidemiologically proven outbreak of C. perfringens food poisoning. In contrast, enterotoxin was not demonstrable in fecal samples of apparently healthy individuals both at high- and low-risk exposure to the organism and enterotoxin or in fecal samples collected 4 to 5 days after a food poisoning outbreak. A 100% prevalence of C. perfringens anti-enterotoxin in sera of human volunteers at high- as well as low-risk exposure to the organism and enterotoxin was recorded with CIEP.
Human rotavirus and its antibody: their coexistence in feces of infants
Authors: Watanabe H , Gust I D , Holmes I H
Published: June 2021

Rotavirus and its antibody were detected by paper disk solid-phase radioimmunoassay or electron microscopy in feces of infants and young children with acute diarrhea. The fecal specimens in which rotavirus was detectable often contained a high titer of antibodies, which were shown by radioimmunoassay to belong mainly to the immunoglobulin G class. Rotavirus was rarely detected in the specimens containing immunoglobulin A antibodies. By dissociation tests carried out by radioimmunoassay, it was shown that the rotavirus particles in some specimens had the same antibody-binding capacity as did cultured simian rotavirus (SA-11), but antibodies in feces usually had low avidity, probably resulting from enzymatic digestion.
Rubella virus hemagglutination with human and animal erythrocytes: effect of age and trypsinization
Authors: Ponzi A N , Pugliese A , Pertusio P
Published: June 2021

Sensitivity to rubella virus hemagglutination differs considerably with newborn as opposed to adult erythrocytes (RBC) in several animal species. In humans, cord RBC are 16 times more sensitive to hemagglutination, whereas hemagglutination titers with newborn RBC are 6 to 16 times higher in chickens, mice, and rabbits. This higher sensitivity is, however, short-lived, and adult RBC values are observed 7 days after birth in mice. Trypsinization has no effect on newborn RBC, but increases sensitivity of adult RBC to that of neonatal RBC and tends to diminish differences among individuals. On the other hand, trypsinization does not further enhance the very high sensitivity of pigeon, duck, and goose RBC or the low sensitivity of both newborn and adult guinea pig RBC. Human cord RBC proved suitable for use in hemagglutination-inhibition tests, since they gave titers comparable to those obtained with other types of RBC and offered some advantages: by comparison with animal RBC, they did not require adsorption to remove nonspecific agglutinins; by comparison with adult human RBC, they did not need trypsinization.
Biochemical characteristics of Haemophilus influenzae in relationship to source of isolation and antibiotic resistance
Authors: Albritton W L , Penner S , Slaney L , Brunton J
Published: June 2021

Based on a limited number of biochemical properties, a system for biotyping Haemophilus influenzae (M. Kilian, Acta Pathol. Microbiol, Scand. Sect. B82:835-842, 1976) was used to analyze the relationship of biotype to source of infection and antibiotic resistance for 600 clinical strains. The distribution of biotypes from bacteremic patients was significantly different (P less than 0.001) from the distribution of biotypes from nonbacteremic patients. Although there appeared to be a correlation between biotype and source of isolation, no single biotype correlated with a specific clinical syndrome in bacteremic patients. The frequency of resistance to antibiotics (ampicillin, tetracycline, chloramphenicol, and kanamycin), which was known to be at least in part plasmid mediated, was determined. Of the 600 isolates, 43 were resistant to at least one antibiotic (30 were ampicillin resistant, 11 were tetracycline resistant, 1 was ampicillin-tetracycline resistant, and 1 was tetracycline-chloramphenicol resistant). Of these 43 resistant isolates, 42 were either biotype I or II. This distribution of biotypes among antibiotic-resustant isolates was significantly different from the overall distribution of biotypes (P is less than 0.001).
Comparative evaluation of a modified zinc sulfate flotation technique
Authors: Bartlett M S , Harper K , Smith N , Verbanac P , Smith J W
Published: June 2021

A modified zinc sulfate flotation technique using Formalinized fecal specimens (F-ZnSO4) was compared to the Formalin-ether (FE) concentration method for the laboratory diagnosis of intestinal parasites. Many laboratories have difficulty storing, using, and disposing of either and need a procedure for concentrating fecal specimens which does not require ether. Comparative data were obtained for the recovery of protozoan cysts and helminth eggs and larvae from feces preserved in Formalin less than and longer than 1 month. Whereas the FE method was found generally to be more efficient, F-ZnSO4 was apparently more effective for the recovery of some species of parasites. F-ZnSO4 was not satisfactory for recovery of schistosome eggs. We conclude that, except for schistosomes, F-ZnSO4 compares favorably to the FE method for detecting infections of clinical significance.
Lymphocyte responses to hemagglutinin and neuraminidase subunits of influenza virus
Authors: Ruben F , Bachmayer H
Published: June 2021

The responses of peripheral lymphocytes to purified hemagglutinin and neuraminidase subunits and other components of an influenza. A virus were measured in 21 normal adults and compared with antibody titers. All had influenza antibodies and demonstrated influenza antigen recognition by lympho-proliferative responses. There was a significantly greater response to the two purified influenza virus surface antigens, hemagglutinin and neuraminidase, than to either whole intact virus or its separated subviral core. No correlation between magnitudes of antibody titers and lymphocyte responsiveness was observed.
Supplemental Material: Formation of the crater suevite sequence from the Chicxulub peak ring: A petrographic, geochemical, and sedimentological characterization
Authors: Kaskes Pim , al. et
Published: June 2021

Figures S1–S7 and Tables S1 and S2.
Solitary cysticercosis of the sternocleidomastoid muscle
Authors: Lal Tusharindra , Paramasivam Surendran , Jayapal Badhrinath , Kataria Riya
Published: June 2021

Cysticercosis is a tropical infection caused by the larval form ofTaenia soliumand is usually known to affect the central nervous system. We report a young man who presented with a swelling in the neck and was treated with surgical excision and antihelminthics.
The secondary transmission pattern of COVID-19 based on contact tracing in Rwanda
Authors: Semakula Muhammed , Niragire FranÇois , Umutoni Angela , Nsanzimana Sabin , Ndahindwa Vedaste , Rwagasore Edison , Nyatanyi Thierry , Remera Eric , Faes Christel
Published: June 2021

Introduction

COVID-19 has shown an exceptionally high spread rate across and within countries worldwide. Understanding the dynamics of such an infectious disease transmission is critical for devising strategies to control its spread. In particular, Rwanda was one of the African countries that started COVID-19 preparedness early in January 2020, and a total lockdown was imposed when the country had only 18 COVID-19 confirmed cases known. Using intensive contact tracing, several infections were identified, with the majority of them being returning travellers and their close contacts. We used the contact tracing data in Rwanda for understanding the geographic patterns of COVID-19 to inform targeted interventions.

Methods

We estimated the attack rates and identified risk factors associated to COVID-19 spread. We used Bayesian disease mapping models to assess the spatial pattern of COVID-19 and to identify areas characterised by unusually high or low relative risk. In addition, we used multiple variable conditional logistic regression to assess the impact of the risk factors.

Results

The results showed that COVID-19 cases in Rwanda are localised mainly in the central regions and in the southwest of Rwanda and that some clusters occurred in the northeast of Rwanda. Relationship to the index case, being male and coworkers are the important risk factors for COVID-19 transmission in Rwanda.

Conclusion

The analysis of contact tracing data using spatial modelling allowed us to identify high-risk areas at subnational level in Rwanda. Estimating risk factors for infection with SARS-CoV-2 is vital in identifying the clusters in low spread of SARS-CoV-2 subnational level. It is imperative to understand the interactions between the index case and contacts to identify superspreaders, risk factors and high-risk places. The findings recommend that self-isolation at home in Rwanda should be reviewed to limit secondary cases from the same households and spatiotemporal analysis should be introduced in routine monitoring of COVID-19 in Rwanda for policy making decision on real time.
Plant-based diets, pescatarian diets and COVID-19 severity: a population-based case–control study in six countries
Authors: Kim Hyunju , Rebholz Casey M , Hegde Sheila , LaFiura Christine , Raghavan Madhunika , Lloyd John F , Cheng Susan , Seidelmann Sara B
Published: June 2021

Background

Several studies have hypothesised that dietary habits may play an important role in COVID-19 infection, severity of symptoms, and duration of illness. However, no previous studies have investigated the association between dietary patterns and COVID-19.

Methods

Healthcare workers (HCWs) from six countries (France, Germany, Italy, Spain, UK, USA) with substantial exposure to COVID-19 patients completed a web-based survey from 17 July to 25 September 2020. Participants provided information on demographic characteristics, dietary information, and COVID-19 outcomes. We used multivariable logistic regression models to evaluate the association between self-reported diets and COVID-19 infection, severity, and duration.

Results

There were 568 COVID-19 cases and 2316 controls. Among the 568 cases, 138 individuals had moderate-to-severe COVID-19 severity whereas 430 individuals had very mild to mild COVID-19 severity. After adjusting for important confounders, participants who reported following ‘plant-based diets’ and ‘plant-based diets or pescatarian diets’ had 73% (OR 0.27, 95% CI 0.10 to 0.81) and 59% (OR 0.41, 95% CI 0.17 to 0.99) lower odds of moderate-to-severe COVID-19 severity, respectively, compared with participants who did not follow these diets. Compared with participants who reported following ‘plant-based diets’, those who reported following ‘low carbohydrate, high protein diets’ had greater odds of moderate-to-severe COVID-19 (OR 3.86, 95% CI 1.13 to 13.24). No association was observed between self-reported diets and COVID-19 infection or duration.

Conclusion

In six countries, plant-based diets or pescatarian diets were associated with lower odds of moderate-to-severe COVID-19. These dietary patterns may be considered for protection against severe COVID-19.
Risk of falls in 4 years of follow-up among Chinese adults with diabetes: findings from the China Health and Retirement Longitudinal Study
Authors: Wen Yue , Liao Jing , Yin Yiqiong , Liu Chunjuan , Gong Renrong , Wu Dongmei
Published: June 2021

Objectives

This study was to determine the incidence of falls and identify baseline factors increased risk for incident falls over time among people with diabetes.

Design

This study was a secondary analysis using the baseline and 4 years of follow-up data from the China Health and Retirement Longitudinal Study (CHARLS).

Setting

A nationally representative survey of 17 500 Chinese residents aged 45 years and older were recruited in the baseline national survey in 2011. These participants were followed up every 2 years.

Participants

A total of 1238 middle-aged and older adults with diabetes and no history of falls at baseline were included in the current study.

Primary and secondary outcome measures

Information on incidence of falls and medical treatment resulting from falls were determined by self-report.

Results

The findings showed that the incidence of falls was 29.4% during 4 years of follow-up. Participants with incident falls were younger, were more likely to be women, had lower education level and were less likely to be current drinkers. In addition, former drinkers were 2.22 times more likely to fall. Socially active individuals were 47% less likely to fall compared with those without social activities. Every 5 kg increase in grip strength was associated with a 13% lower risk of falls. A 10 mg/dL higher total cholesterol and 1 mg/dL higher blood urea nitrogen were associated with a 4% and 6% higher risk of falls. Finally, participants with depressive symptoms were 1.47 times more likely to fall compared with those without depressive symptoms.

Conclusions

These findings underscore the importance of developing a fall prevention programme for those with diabetes, and this programme should address potentially modifiable risk factors, including levels of total cholesterol, blood urea nitrogen, social activity, depressive symptoms and grip strength.
Occupational prestige and sickness absence inequality in employed women and men in Sweden: a registry-based study
Authors: Nwaru Chioma Adanma , Berglund Tomas , Hensing Gunnel
Published: June 2021

Objectives

Socioeconomic position has been linked to sickness absence (SA). However, less is known about the role of occupational prestige, a measure of social status afforded by one’s occupation, in SA. We investigated the association between occupational prestige and SA and the distribution of the association in women and men. We also examined the effect of intersections of gender and occupational prestige on SA.

Design

Longitudinal.

Setting

A nationwide representative sample of Swedish working population.

Participants

97 397 employed individuals aged 25–59 years selected from the 2004, 2007 and 2010 waves of the Swedish Labour Force Survey and prospectively linked to the Swedish Longitudinal Integration Database for Health Insurance and Labour Market Studies.

Outcome measures

The number of SA days in any particular year during a 3-year follow-up and long-term (>120 days) SA based on those with at least one sick leave spell during the follow-up.

Results

Occupational prestige was weakly associated with SA in the total sample after adjusting for potential confounders. In the gender-stratified analysis, women in lower prestige occupations had higher absenteeism rates than women in high prestige occupations; men in lower prestige occupations had higher odds for long-term SA than men in high prestige occupations. In the intersectional analysis, women regardless of prestige level and men in lower prestige occupations had higher probability of SA compared with men in high prestige occupations. Women in high prestige occupations had the highest absenteeism rates (incidence rate ratio (IRR), 2.25, 95% CI, 2.20 to 2.31), while men in medium prestige occupations had the lowest rates (IRR, 1.17, 95% CI, 1.13 to 1.20). Compared with the rest of the groups, men in low and medium prestige occupations had higher odds for long-term absence.

Conclusion

There is need to pay close attention to occupational prestige as a factor that may influence health and labour market participation.
Incidence and prediction of ankle injury risk: a prospective cohort study on 91 contemporary preprofessional dancers
Authors: Mailuhu Adinda K E , van Rijn Rogier M , Stubbe Janine H , Bierma-Zeinstra Sita M A , van Middelkoop Marienke
Published: June 2021

Objectives

This study examines the incidence of ankle injuries and identifies ankle injury risk among contemporary preprofessional dancers.

Methods

A total of 91 first-year contemporary preprofessional dancers were prospectively followed during one academic year. Self-reported ankle injuries, assessed with the Oslo Sports Trauma Research Centre questionnaire, were categorised as all complaint ankle injuries, substantial ankle injuries or time-loss ankle injuries. In addition, ankle injuries leading to medical attention were included. Regression analyses were used to determine the association between potential risk factors (dancer characteristics, history of ankle injury in the previous year, ankle range of motion and dorsiflexion) and ankle injuries.

Results

The 1-year ankle injury incidence proportion was 18.7% (n=17), 8.8% (n=8), 15.4% (n=14) and 7.7% (n=7), respectively, for all complaint ankle injuries, ankle injuries requiring medical attention, time-loss injuries and substantial injuries. Being male (OR=0.27; 95% CI 0.09 to 0.75) and being a student of the Bachelors in Dance and Education (OR=0.27; 95% CI 0.08 to 0.97) were univariately associated with a lower risk of an ankle injury.

Conclusion

Almost 20% of first-year preprofessional dancers reported an ankle injury, with more than 80% of the dancers reporting that their injury leads to dance time loss. Males and students of the bachelors in dance and education were at lower risk of ankle injuries. As ankle injuries are common among dancers, studies with larger sample sizes, a more heterogeneous population (eg, different dance styles) and longer follow-up periods are necessary to evaluate the impact of ankle injuries in further detail.
E-scooter incidents in Berlin: an evaluation of risk factors and injury patterns
Authors: Uluk Deniz , Lindner Tobias , Dahne Michael , Bickelmayer Jens Werner , Beyer Kassandra , Slagman Anna , Jahn Friedrich , Willy Christian , Möckel Martin , Gerlach Undine A
Published: June 2021

Background

E-scooters have emerged as a frequently used vehicle in German cities due to their high availability and easy access. However, investigations about the causes and mechanisms of E-scooter incidents and their trauma-specific consequences are rare.

Methods

We analysed all patients involved in E-scooter incidents from June to December 2019 who presented to four inner-city EDs in Berlin. The prospective data included patient-related and incident-related data, information on injury patterns and therapy, responses in a voluntary questionnaire concerning E-scooter use and general traffic experience.

Results

248 patients (129 males; median age 29 years (5–81)) were included: 41% were tourists and 4% were children. Most incidents (71%) occurred between July and September 2019, the majority occurring at weekends (58%). The injury pattern was mostly multifocal, affecting the lower (42%) and upper limbs (37%) and the head (40%). Traumatic brain injury was associated with alcohol consumption. Inpatient admission was recorded in 25%, surgery in 23%.

Conclusion

This study has defined the incidence of injury related to E-scooter use in a major European city. Stricter laws governing the use of E-scooters, the wearing of helmets and technical modifications to the E-scooter platforms might decrease E-scooter-associated incidents and resulting injuries in the future.

Trial registration number

German Clinical Trials Registry (DRKS00018061).
Anti-PD-1 elicits regression of undifferentiated pleomorphic sarcomas with UV-mutation signatures
Authors: Cheung Laurene S , Chen Lingling , Oke Teniola F , Schaffer Thomas B , Boudadi Karim , Ngo Jillian T , Gross John McMahon , Kemberling Holly , Diaz Luis A , Lipson Evan , Sidhom John-WIlliam , Taube Janis , Anders Robert , Pardoll Drew M , Le Dung T , Meyer Christian F , Llosa Nicolas
Published: June 2021

Undifferentiated pleomorphic sarcoma (UPS), an aggressive soft-tissue sarcoma of adults, has been characterized by low tumor mutational burden (TMB) and high copy number alterations. Clinical trials of programmed death-1 (PD-1) blockade in UPS have reported widely varying efficacy. We describe two patients with recurrent scalp UPS that experienced clinical benefit from PD-1 blockade. These tumors had high TMB with a UV-induced mutational pattern. Analysis of additional head and neck UPS cases identified five out of seven tumors with high TMB and an ultraviolet (UV) mutational signature. Head and neck UPS tumors also had increased programmed death-ligand 1 (PD-L1) expression and CD8+ T cell infiltration as compared with UPS tumors arising from other sites. In summary, we found that UPS tumors of the head and neck, but not elsewhere, have a PD-L1+, T-cell-inflamed tumor microenvironment and high TMB, suggesting that these tumors represent a distinct genetic subgroup of UPS for which immune checkpoint inhibitor therapy might be effective.
LGBT testimony and the limits of trust
Authors: Priest Maura
Published: June 2021

In, ‘Forever young: the ethics of ongoing puberty suppression (OPS) for non-binary adults,’ Notini et al discuss the risks, harms and benefits of treating non-binary patients via identity-affirming OPS. Notini et al’s article makes a strong case for OPS’s permissibility, and their conclusion will not be disputed here. Instead, I directly focus on issues that their article addressed only indirectly. This article will use a hypothetical case study to show that while Notini et al’s ethical conclusion might be spot on, that perhaps the method they took to get there was superfluous. If the medical community is to take LGBT testimony seriously (as they should) then it is no longer the job of physicians to do their own weighing of the costs and benefits of transition-related care. Assuming the patient is informed and competent, then only the patient can make this assessment, because only the patient has access to the true weight of transition-related benefits. Moreover, taking LGBT patient testimony seriously also means that parents should lose veto power over most transition-related paediatric care.
Stents for progressively symptomatic paediatric intracranial arterial dissection
Authors: Jay Catherine R G , Duncan Aubrey N , Ellika Shehanaz K , Bender Matthew T
Published: June 2021

Arterial dissection is an uncommon cause of paediatric stroke. Medical therapy remains first-line for treatment. There are few reports of neurovascular stents for paediatric intracranial arterial dissection. Two adolescents presented with neurological deficits and CT angiography concerning for supraclinoid internal carotid artery stenosis. The diagnosis of dissection was secured through a combination of vessel wall MRI and digital subtraction angiography. The patients experienced progressive ischaemic symptoms, despite medical management including anticoagulation, and required stenting. The stents used were a Neuroform EZ and an Atlas. Both patients recovered to Modified Rankin Scale (mRS) 0 and had restored vessel calibre on 6-month follow-up digital subtraction angiography. Neurovascular stents can be used to treat progressively symptomatic intracranial arterial dissections in the paediatric population if medical therapy fails.
Efficacy and safety of tofacitinib modified-release 11 mg once daily plus methotrexate in adult patients with rheumatoid arthritis: 24-week open-label phase results from a phase 3b/4 methotrexate withdrawal non-inferiority study (ORAL Shift)
Authors: Cohen Stanley B , Pope Janet , Haraoui Boulos , Mysler Eduardo , Diehl Annette , Lukic Tatjana , Liu Shixue , Stockert Lori , Germino Rebecca , Menon Sujatha , Shi Harry , Keystone Edward C
Published: June 2021

Objectives

To report the efficacy, safety and patient-reported outcome measures (PROs) of tofacitinib modified-release 11 mg once daily plus methotrexate in patients with rheumatoid arthritis (RA) from the open-label phase of Oral Rheumatoid Arthritis Trial (ORAL) Shift.

Methods

ORAL Shift was a global, 48-week, phase 3b/4 withdrawal study in patients with moderate to severe RA and an inadequate response to methotrexate. Patients received open-label tofacitinib modified-release 11 mg once daily plus methotrexate; those who achieved low disease activity (LDA; Clinical Disease Activity Index (CDAI)≤10) at week 24 were randomised to receive blinded tofacitinib 11 mg once daily plus placebo (ie, blinded methotrexate withdrawal) or continue with blinded tofacitinib 11 mg once daily plus methotrexate for another 24 weeks. Efficacy, PROs and safety from the open-label phase are reported descriptively.

Results

Following screening, 694 patients were enrolled and received tofacitinib plus methotrexate in the open-label phase. At week 24, 527 (84.5%) patients achieved CDAI-defined LDA. Improvements from baseline to weeks 12 and 24 were generally observed for all efficacy outcomes (including measures of disease activity, and response, LDA and remission rates) and PROs. Adverse events (AEs), serious AEs and discontinuations due to AEs were reported by 362 (52.2%), 20 (2.9%) and 41 (5.9%) patients, respectively. No deaths were reported.

Conclusions

Tofacitinib modified-release 11 mg once daily plus methotrexate conferred improvements in disease activity measures, functional outcomes and PROs, with most (84.5%) patients achieving CDAI-defined LDA after 24 weeks of open-label treatment; the safety profile was generally consistent with the historic safety profile of tofacitinib.

Funded by Pfizer Inc;NCT02831855.
Clinical imaging factors of excellent outcome after thrombolysis in large-vessel stroke: a THRACE subgroup analysis
Authors: Riou-Comte Nolwenn , Gory Benjamin , Soudant Marc , Zhu François , Xie Yu , Humbertjean Lisa , Mione Gioia , Oppenheim Catherine , Guillemin Francis , Bracard Serge , Richard Sébastien
Published: June 2021

Background

For patients with stroke with large-vessel occlusion (LVO), study of factors predicting response to intravenous thrombolysis (IVT) would allow identifying subgroups with high expected gain, and those for whom it could be considered as futile, and even detrimental. From patients included in the Mechanical Thrombectomy After Intravenous Alteplase vs Alteplase Alone After Stroke trial, we investigated clinical-imaging factors associated with optimal response to IVT.

Methods

We included patients receiving IVT alone. Excellent outcome was defined by a 3-month modified Rankin Scale (mRS) score ≤1. Clinical-imaging predictors were assessed on multivariate analysis after multiple imputations. The predictive performance of the model was assessed with the C-statistic.

Results

Among 247 patients with LVO treated with IVT alone, 77 (31%) showed 3-month mRS ≤1. Predictors of 3-month mRS ≤1 were no medical history of hypertension (OR 2.43; 95% CI 1.74 to 3.38; p=0.007); no current smoking (OR 2.76; 95% CI 1.79 to 4.26; p=0.02); onset-to-IVT time (OR 0.47 per hour increase; 95% CI 0.23 to 0.78; p=0.003); diffusion-weighted imaging (DWI) volume (OR 0.78 per 10 mL increase; 95% CI 0.68 to 0.89; p=0.0004); presence of susceptibility vessel sign (SVS) (OR 7.89; 95% CI 1.65 to 37.78; p=0.01) and SVS length (OR 0.87 per mm increase; 95% CI 0.80 to 0.94; p=0.001). The prediction models showed a C-statistic=0.79 (95% CI 0.79 to 0.80).

Conclusions

In patients with stroke with anterior-circulation LVO treated with IVT alone, predictors of excellent outcome at 3 months were no medical history of hypertension or current smoking, reduced onset-to-IVT time, small DWI volume, presence of SVS and short SVS length. These predictive factors could help practitioners in decision-making for IVT implementation in reperfusion strategies, all the more for the drip and ship paradigm.

Trial registration number

NCT01062698.
Support for cigarette filter waste policies among US adults
Authors: Patel Minal , Cuccia Alison F , Folger Shanell , Benson Adam F , Vallone Donna , Novotny Thomas E
Published: June 2021

Introduction

Little is known on whether cigarette filter-related knowledge or beliefs are associated with support for policies to reduce their environmental impact.

Methods

A cross-sectional, population-based sample of US adults aged 18–64 years (n=2979) was used to evaluate filter-related knowledge and beliefs by smoking status using data collected between 24 October 2018 and 17 December 2018. Multivariate logistic regression models explored whether these knowledge and belief items were associated with support for two policies, a US$0.75 litter fee and a ban on sales of filtered cigarettes, controlling for demographic characteristics and smoking status.

Results

Regardless of smoking status, 71% did not know plastic was a cigarette filter component and 20% believed filters were biodegradable. Overall, 23% believed filters reduce health harms and 60% believed filters make it easier to smoke; 90% believed cigarette butts are harmful to the environment. Individuals believing cigarette butts harmed the environment were more likely to support a litter fee (adjusted OR (aOR)=2.33, 95% CI: 1.71 to 3.17). Individuals believing that filters are not biodegradable had higher odds of supporting a litter fee (OR=1.47, 95% CI: 1.15 to 1.88). Respondents believing that filters do not make cigarettes less harmful were more likely to support a litter fee (aOR=1.50, 95% CI: 1.20 to 1.88) and filter ban (aOR=2.03, 95% CI: 1.64 to 2.50). Belief that filters make it easier to smoke was associated with decreased support for a filter ban (aOR=0.69, 95% CI: 0.58 to 0.83).

Conclusions

Comprehensive efforts are needed to educate the public about the impact of cigarette filters in order to build support for effective tobacco product waste policy.
Advances in the conventional clinical treatment for hepatoblastoma and therapeutic innovation
Authors: Chen Zhixue , Dong Rui
Published: June 2021

Background

Hepatoblastoma (HB) is a rare malignancy usually occurring in children under 3 years old. With advancements in surgical techniques and molecular biology, new treatments have been developed.

Data resources

The recent literatures on new treatments, molecular mechanisms and clinical trials for HB were searched and reviewed.

Results

Surgical resection remains the main option for treatment of HB. Although complete resection is recommended, a resection with microscopical positive margins (R1) may have similar 5-year overall survival and 5-year event-free survival (EFS) rates after cisplatin chemotherapy and the control of metastasis, as only once described so far. Indocyanine green-guided surgery can help achieve precise resection. Additionally, associating liver partition and portal vein ligation for staged hepatectomy can rapidly increase future liver remnant volume compared with portal vein ligation or embolization. Cisplatin-containing chemotherapies slightly differ among the guidelines from the International Childhood Liver Tumors Strategy Group (SIOPEL), Children’s Oncology Group (COG) and Chinese Anti-Cancer Association Pediatric Committee (CCCG), and the 3-year EFS rate of patients in SIOPEL and CCCG studies was recently shown to be higher than that in COG studies. Liver transplantation is an option for patients with unresectable HB, and successful cases of autologous liver transplantation have been reported. In addition, effective inhibitors of important targets, such as the mTOR (mammalian target of rapamycin) inhibitor rapamycin, β-catenin inhibitor celecoxib and EpCAM (epithelial cell adhesion molecule) inhibitor catumaxomab, have been demonstrated to reduce the activity of HB cells and to control metastasis in experimental research and clinical trials.

Conclusion

These advances in surgical and medical treatment provide better outcomes for children with HB, and identifying novel targets may lead to the development of future targeted therapies and immunotherapies.