The Torque Teno Virus Titer in Saliva Reflects the Level of Circulating CD4+ T Lymphocytes and HIV in Individuals Undergoing Antiretroviral Maintenance Therapy

IntroductionTorque teno virus (TTV) is a non-pathogenic virus present in body fluids. Its titer in the circulation increases in association with immune suppression, such as in HIV-infected individuals. We evaluated if the TTV titer in saliva from HIV-positive individuals undergoing antiretroviral therapy (ART) was related to the circulating CD4+ T lymphocyte concentration and the HIV titer.MethodsSaliva was collected from 276 asymptomatic individuals undergoing ART, and an additional 48 individuals positive for AIDS-associated Kaposi's Sarcoma (AIDS-KS). The salivary TTV titer was measured by gene amplification analysis. The circulating CD4+ T lymphocyte and HIV levels were obtained by chart review.ResultsTTV was detectable in saliva from 80% of the asymptomatic subjects and 87% of those with AIDS-KS. In the asymptomatic group the median log10 TTV titer/ml was 3.3 in 200 males vs. 2.4 in 76 females (p < 0.0001). TTV titer/ml was 3.7 when HIV was acquired by intravenous drug usage, 3.2 when by sexual acquisition and 2.4 when blood transfusion acquired. The salivary TTV titer was inversely correlated with the circulating CD4+ T lymphocyte level (p < 0.0001) and positively correlated with the circulating HIV concentration (p = 0.0005). The median salivary TTV titer and circulating HIV titer were higher, and the CD4+ count was lower, in individuals positive for AIDS-KS than in the asymptomatic subjects (p < 0.0001).ConclusionThe TTV titer in saliva is a potential biomarker for monitoring immune status in individuals undergoing ART.

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Histopathological Features of Symptomatic and Asymptomatic Honeybees Naturally Infected by Deformed Wing Virus

Pathogens ◽

10.3390/pathogens10070874 ◽

2021 ◽

Vol 10 (7) ◽

pp. 874

Author(s):

Karen Power ◽

Manuela Martano ◽

Gennaro Altamura ◽

Nadia Piscopo ◽

Paola Maiolino

Keyword(s):

Viral Load ◽

Asymptomatic Group ◽

Deformed Wing Virus ◽

Stage Of Development ◽

Pathogenic Action ◽

Degenerative Alterations ◽

Flight Muscles ◽

Asymptomatic Individuals ◽

Histopathological Results

Deformed wing virus (DWV) is capable of infecting honeybees at every stage of development causing symptomatic and asymptomatic infections. To date, very little is known about the histopathological lesions caused by the virus. Therefore, 40 honeybee samples were randomly collected from a naturally DWV infected hive and subjected to anatomopathological examination to discriminate between symptomatic (29) and asymptomatic (11) honeybees. Subsequently, 15 honeybee samples were frozen at −80° and analyzed by PCR and RTqPCR to determinate the presence/absence of the virus and the relative viral load, while 25 honeybee samples were analyzed by histopathological techniques. Biomolecular results showed a fragment of the expected size (69bp) of DWV in all samples and the viral load was higher in symptomatic honeybees compared to the asymptomatic group. Histopathological results showed degenerative alterations of the hypopharyngeal glands (19/25) and flight muscles (6/25) in symptomatic samples while 4/25 asymptomatic samples showed an inflammatory response in the midgut and the hemocele. Results suggest a possible pathogenic action of DWV in both symptomatic and asymptomatic honeybees, and a role of the immune response in keeping under control the virus in asymptomatic individuals.

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Differences in Hip Joint Biomechanics and Muscle Activation in Individuals With Femoroacetabular Impingement Compared With Healthy, Asymptomatic Individuals: Is Level-Ground Gait Analysis Enough?

Orthopaedic Journal of Sports Medicine ◽

10.1177/2325967118769829 ◽

2018 ◽

Vol 6 (5) ◽

pp. 232596711876982 ◽

Cited By ~ 8

Author(s):

Derek J. Rutherford ◽

Janice Moreside ◽

Ivan Wong

Keyword(s):

Femoroacetabular Impingement ◽

Hip Joint ◽

Muscle Activation ◽

Gluteus Maximus ◽

Knee Extensors ◽

Joint Function ◽

Asymptomatic Group ◽

Level Walking ◽

Hip Function ◽

Asymptomatic Individuals

Background: Femoroacetabular impingement (FAI) is a recognized cause of hip and groin pain and a significant factor in hip joint function during sport. Objective tests for understanding hip function are lacking in this population. Purpose: To determine whether biomechanical and electromyographic features of hip function during level-ground walking differ between a group diagnosed with FAI and those with no symptoms of FAI. Study Design: Controlled laboratory study. Methods: A total of 20 asymptomatic individuals and 20 individuals with FAI walked on a dual-belt instrumented treadmill at self-selected walking velocities. Sagittal and frontal plane joint motions, moments, and muscle activation for the gluteus medius, gluteus maximus, rectus femoris, and medial and lateral hamstrings were analyzed. Discrete measures were extracted from each biomechanical waveform, and principal component analysis was used to determine hip joint muscle activation and hip adduction moment patterns. Statistical significance was determined by use of Student t tests with Bonferroni adjustments for multiple comparisons (α = .05). Results: Individuals with FAI walked more slowly ( P = .015) and had lower self-reported function ( P < .001). No differences in muscle strength were found between the symptomatic and contralateral legs in the FAI group ( P > .017), but those with FAI had lower strength in the knee extensors and flexors and the hip extensors, flexors, and adductors compared with the asymptomatic group ( P < .017). Individuals with unilateral symptomatic FAI walked with similar biomechanical and hip muscle electromyographic results bilaterally. The only differences found were a greater amplitude of gluteus maximus activation in the FAI symptomatic leg compared with the asymptomatic group and greater medial hamstring activation than lateral hamstring activation in the FAI group in both limbs compared with the asymptomatic group. Conclusion: Individuals with FAI were generally deconditioned and reported significantly more functional limitations. No biomechanical differences existed between groups during level walking, yet hamstring and gluteus maximus activation differed when the symptomatic group was compared with the asymptomatic group. Clinical Relevance: The field lacks objective testing of hip joint function to understand implications of FAI for dynamic movements, particularly with applications to biomechanics and electromyography. Level walking was of limited value for understanding FAI hip function, and the development of a more challenging gait assessment is warranted.

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Altered Scapular Time Series in Individuals With Subacromial Pain Syndrome

Journal of Applied Biomechanics ◽

10.1123/jab.2019-0247 ◽

2020 ◽

Vol 36 (2) ◽

pp. 113-121

Author(s):

Denise M. Rossi ◽

Renan A. Resende ◽

Gisele H. Hotta ◽

Sérgio T. da Fonseca ◽

Anamaria S. de Oliveira

Keyword(s):

Effect Size ◽

Principal Component ◽

Arm Movement ◽

Pain Syndrome ◽

Asymptomatic Group ◽

Symptomatic Group ◽

Subacromial Pain Syndrome ◽

Posterior Tilt ◽

Asymptomatic Individuals ◽

Anterior Posterior

Altered scapular movement in subacromial pain syndrome has been demonstrated using discrete data reduction approach. However, this approach does not consider the data collinearity and variability, and scapular translations are poorly investigated in symptomatic individuals. The purpose of this study was to investigate the scapular rotation and translation of asymptomatic individuals and those with subacromial pain syndrome during arm motions using principal component analysis. Scapulothoracic kinematics were evaluated in 47 participants with subacromial pain syndrome and 50 asymptomatic individuals. The symptomatic group had increased range of scapular anterior/posterior tilt during arm elevation (P = .01, effect size = .59) and arm lowering (P < .01, effect size = .61), and increased range of scapular forward/backward translation during arm lowering (P < .01, effect size = .60) compared with the asymptomatic group. In addition, the symptomatic group had a reduced difference in anterior tilt angular velocities between the early-arm and mid-arm lowering phases and between the mid- and late-arm lowering phases compared with the asymptomatic group (P = .03, effect size = .44). This study demonstrated that scapular anterior/posterior tilt motion and angular velocity and scapular forward/backward translation of symptomatic individuals were different from asymptomatic individuals when considering the entire arm movement.

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Receptor activator of NF-κB ligand (RANKL) increases the release of neutrophil products associated with coronary vulnerability

Thrombosis and Haemostasis ◽

10.1160/th11-05-0324 ◽

2012 ◽

Vol 107 (01) ◽

pp. 124-139 ◽

Cited By ~ 24

Author(s):

Maria Bertolotto ◽

Sébastien Lenglet ◽

Nicolas Vuilleumier ◽

Katia Galan ◽

Sabrina Pagano ◽

...

Keyword(s):

Neutrophil Migration ◽

Calcium Score ◽

Coronary Calcification ◽

Serum Levels ◽

Blood Stream ◽

Intracellular Signalling Pathways ◽

Potential Marker ◽

Potential Biomarker ◽

Receptor Activator ◽

Asymptomatic Subjects

SummaryThe “blood vulnerability”, resulting from the complex balance between serum molecules and inflammatory cell atherosclerotic activities, is a major determinant in the evaluation of the “global patient cardiovascular vulnerability”. In the present study, we focused on the role of the soluble receptor activator of nuclear factor kappa-B (NF-κB) ligand (RANKL, a potential marker of coronary calcification and vulnerability) in the release of neutrophilic proteases. Then, the association between these mediators and the degree of coronary calcification (assessed by coronary calcium score [CCS]) was investigated in 20 subjects (aged ≥65 years) asymptomatic for cardiovascular disease. Results showed that RANKL dose-dependently induced matrix metalloprotease (MMP)-8 and MMP-9 release from human primary neutrophils cultured in Teflon dishes (suspension condition, mimicking cells circulating in the blood stream). Conversely, when adherent to polystyrene, neutrophils became unresponsive to RANKL. RANKL did not influence the release of other neutrophilic products in suspension and adherence cultures as well as neutrophil migration. RANKL-induced release of MMPs was dependent on the activation of defined intracellular signalling pathways (PI3K/Akt and ERK1/2). In asymptomatic subjects, serum levels of RANKL, MMP-8 and MMP-9 positively correlated with CCS, reflecting a potential relationship between circulating RANKL and coronary calcification. In conclusion, RANKL increased the release of neutrophilic products potentially related to the “blood” vulnerability via defined intracellular pathways. Serum levels of RANKL might represent a potential biomarker of coronary calcification and related cardiovascular risk.

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Differences in haematological parameters and haemoglobin phenotypes in symptomatic and asymptomatic subjects with Plasmodium falciparum infection in parts of Kaduna metropolis, Nigeria

African Journal of Clinical and Experimental Microbiology ◽

10.4314/ajcem.v22i3.12 ◽

2021 ◽

Vol 22 (3) ◽

pp. 407-414

Author(s):

K.B. Dikwa ◽

D.B. Maikaje ◽

U.A. Yahaya ◽

A.B. Suleiman

Keyword(s):

Plasmodium Falciparum ◽

Plasmodium Falciparum Malaria ◽

Blood Film ◽

Falciparum Infection ◽

Haematological Parameters ◽

Asymptomatic Malaria ◽

Symptomatic Infection ◽

Asymptomatic Individuals ◽

Asymptomatic Subjects ◽

Apparently Healthy

Background: Plasmodium falciparum is the leading cause of malaria morbidity and mortality in Nigeria with varied symptoms and haematological consequences. The objective of this study is to assess the differences in haematological parameters and haemoglobin phenotypes in symptomatic P. falciparum infected and apparently healthy asymptomatic individuals in parts of Kaduna metropolis.Methodology: A total of 1000 subjects; 500 symptomatic and 500 apparently healthy subjects asymptomatic for malaria, were recruited from selected hospitals and National Blood Bank in Kaduna metropolis. Blood samples were collected for thick and thin film microscopy to determine malaria parasitaemia and parasite species identification respectively. Haematological parameters were determined using automated blood analyser (KX-21N, Sysmex, Japan) and haemoglobin phenotypes by alkaline cellulose acetate electrophoresis.Results: Of the 1000 subjects recruited, 347 (34.7%) were positive for P. falciparum on blood film, which included 226 (45.2%) of 500 symptomatic and 121 (24.2%) of 500 asymptomatic subjects (p<0.00001). Of the 347 P. falciparum infected subjects, 275 (79.3%) had HbAA, 61 (17.6%) had HbAS, 1 (0.3%) had HbAC, 8 (2.3%) had HbSS, and 2 (0.6%) had HbSSf phenotypes. One hundred and sixty-three (72.1%) of the 226 symptomatic subjects had HbAA while 112 (92.6%) of the 121 asymptomatic subjects had HbAA, which indicated a significantly higher frequency of asymptomatic malaria in subjects with HbAA (p<0.00001). Conversely, 53 (23.5%) of the 226 symptomatic subjects had HbAS while 8 (6.6%) of 121 asymptomatic subjects had HbAS, indicating a significantly higher frequency of symptomatic malaria in subjects with HbAS (p=0.000086). The frequency of parasitaemia > 3,000 parasites/μL of blood was 100% for HbSSf, 25% for HbSS, 8.2% for HbAS and 2.2% for HbAA, which showed significantly higher frequency in subjects with HbSS (X2=7.5989, p=0.0054) and HbAS (X2=3.9627, p=0.046519) compared to HbAA. In symptomatic subjects, only MCHC value was significantly higher in subjects with HbAS (33.21±2.430) compared to those with HbAA (32.09 ±2.315) (p=0.003), while all other haematological parameters were not significantly different (p>0.05). In asymptomatic subjects, none of the haematological parameters was significantly different between subjects with HbAS and HbAA (p>0.05).Conclusion: Although the frequency of P. falciparum infection in this study is generally higher in subjects with HbAA, symptomatic infection and higher parasite density are associated with HbAS, HbSS and HbSSf. Effective utilisation of personal preventive measures by inhabitants, in addition to current malaria control and intervention strategies should be adequately implemented in Kaduna metropolis. Keywords: Haematological parameters, haemoglobin, electrophoresis, Plasmodium falciparum, malaria Différences dans les paramètres hématologiques et les phénotypes d'hémoglobine chez les sujets symptomatiques et asymptomatiques atteints d'une infection à Plasmodium falciparum dans certaines parties de la métropole de Kaduna, Nigéria Contexte: Plasmodium falciparum est la principale cause de morbidité et de mortalité liées au paludisme au Nigéria avec des symptômes et des conséquences hématologiques variés. L'objectif de cette étude est d'évaluer les différences de paramètres hématologiques et de phénotypes d'hémoglobine chez des individus symptomatiques infectés par P. falciparum et asymptomatiques apparemment en bonne santé dans certaines parties de la métropole de Kaduna. Méthodologie: Un total de 1000 sujets; 500 sujets symptomatiques et 500 sujets apparemment sains asymptomatiques pour le paludisme ont été recrutés dans certains hôpitaux et dans la Banque nationale du sang de la métropole de Kaduna. Des échantillons de sang ont été prélevés pour la microscopie à couche épaisse et mince afin de déterminer respectivement la parasitémie du paludisme et l'identification des espèces de parasites. Les paramètres hématologiques ont été déterminés à l'aide d'un analyseur sanguin automatisé (KX-21N, Sysmex, Japon) et des phénotypes d'hémoglobine par électrophorèse sur acétate de cellulose alcaline. Résultats: Sur les 1000 sujets recrutés, 347 (34,7%) étaient positifs pour P. falciparum sur frottis sanguin, qui comprenait 226 (45,2%) de 500 sujets symptomatiques et 121 (24,2%) de 500 sujets asymptomatiques (p<0,00001). Sur les 347 sujets infectés par P. falciparum, 275 (79,3%) avaient HbAA, 61 (17,6%) avaient HbAS, 1 (0,3%) avaient HbAC, 8 (2,3%) avaient HbSS et 2 (0,6%) avaient des phénotypes HbSSf. Cent soixante-trois (72,1%) des 226 sujets symptomatiques avaient une HbAA tandis que 112 (92,6%) des 121 sujets asymptomatiques avaient une HbAA, ce qui indiquait une fréquence significativement plus élevée de paludisme asymptomatique chez les sujets avec HbAA (p<0,00001). À l'inverse, 53 (23,5%) des 226 sujets symptomatiques avaient une HbAS tandis que 8 (6,6%) des 121 sujets asymptomatiques avaient une HbAS, indiquant une fréquence significativement plus élevée de paludisme symptomatique chez les sujets avec HbAS (p=0,000086). La fréquence de parasitémie> 3000 parasites / μL de sang était de 100% pour l'HbSSf, 25% pour l'HbSS, 8,2% pour l'HbAS et 2,2% pour l'HbAA, ce qui a montré une fréquence significativement plus élevée chez les sujets atteints d'HbSS (X2=7,5989, p=0,0054) et HbAS (X2=3,9627, p=0,046519) par rapport à l'HbAA. Chez les sujets symptomatiques, seule la valeur MCHC était significativement plus élevée chez les sujets avec HbAS (33,21±2,430) par rapport à ceux avec HbAA (32,09±2,315) (p=0,003), tandis que tous les autres paramètres hématologiques n'étaient pas significativement différents (p>0,05). Chez les sujets asymptomatiques, aucun des paramètres hématologiques n'était significativement différent entre les sujets avec HbAS et HbAA (p>0,05). Conclusion: Bien que la fréquence des infections à P. falciparum dans cette étude soit généralement plus élevée chez les sujets atteints d'HbAA, une infection symptomatique et une densité parasitaire plus élevée sont associées à l'HbAS, l'HbSS et l'HbSSf. Une utilisation efficace des mesures de prévention personnelle par les habitants, en plus des stratégies actuelles de lutte antipaludique et d'intervention, devrait être mise en oeuvre de manière adéquate dans la métropole de Kaduna. Mots clés: Paramètres hématologiques, hémoglobine, électrophorèse, Plasmodium falciparum, paludisme

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Feasibility and utility of rapid antigen testing for COVID-19 in a university residence: a cross sectional study

10.1101/2021.05.24.21257732 ◽

2021 ◽

Author(s):

Sabrina Wong ◽

Marc Gabriel Romney ◽

Kristen Haase ◽

Nancy Matic ◽

Manon Ranger ◽

...

Keyword(s):

Cross Sectional Study ◽

Contact Tracing ◽

Rapid Testing ◽

Asymptomatic Group ◽

Easy Method ◽

Cross Sectional ◽

University Of British Columbia ◽

The Mean ◽

Asymptomatic Individuals ◽

Antigen Testing

Importance: Understanding feasibility of rapid testing in congregate living setting provides critical data to reduce the risk of outbreaks in these settings. Objective: Use rapid antigen screening to detect SARS-CoV-2 in an asymptomatic group of university students and staff. Design: Cross-sectional Setting: University of British Columbia, Vancouver, Canada. Participants: Students and staff living or working in congregate housing. Intervention: Health care professional administered rapid antigen test Main Outcomes and measures: Use of BD Veritor rapid antigen testing and asymptomatic participants experiences with rapid testing Results: A total of 3536 BD Veritor tests were completed in 1141 unique individuals. One third of participants completed between two to four tests and 21% were screened five or more times. The mean number of tests completed per person was three. The mean length of time between those who had more than one test was seven days. There were eight false positives and 25 PCR confirmed COVID-19 positive individuals identified through this work. All individuals reported having no symptoms that they attributed to COVID-19. Almost all (n=22, 88%) COVID-19 positive cases were found in male participants. A total of 86 additional students from multiple different student residences (n=9) were asked to self-isolate while they waited for their COVID-19 diagnostic test results. An average of seven additional students positive for COVID-19 living in congregate housing were identified through contact tracing by finding one positive case. Conclusions and relevance: Rapid testing is a relatively inexpensive and operationally easy method of identifying asymptomatic individuals with COVID-19.

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Increased plasma Gln and Leu Raand inappropriately low muscle protein synthesis rate in AIDS wasting

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1998.275.4.e577 ◽

1998 ◽

Vol 275 (4) ◽

pp. E577-E583 ◽

Cited By ~ 12

Author(s):

Kevin E. Yarasheski ◽

Jeffrey J. Zachwieja ◽

Jennifer Gischler ◽

Jan Crowley ◽

Mary M. Horgan ◽

...

Keyword(s):

Protein Synthesis ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

Whole Body ◽

Synthesis Rate ◽

Protein Synthesis Rate ◽

Asymptomatic Group ◽

Body Protein ◽

Asymptomatic Subjects ◽

Muscle Protein Synthesis Rate

Muscle protein wasting occurs in human immunodeficiency virus (HIV)-infected individuals and is often the initial indication of acquired immunodeficiency syndrome (AIDS). Little is known about the alterations in muscle protein metabolism that occur with HIV infection. Nine subjects with AIDS wasting (CD4 < 200/mm3), chronic stable opportunistic infections (OI), and ≥10% weight loss, fourteen HIV-infected men and one woman (CD4 > 200/mm3) without wasting or OI (asymptomatic), and six HIV-seronegative lean men (control) received a constant intravenous infusion of [1-13C]leucine (Leu) and [2-15N]glutamine (Gln). Plasma Leu and Gln rate of appearance (Ra), whole body Leu turnover, disposal and oxidation rates, and [13C]Leu incorporation rate into mixed muscle protein were assessed. Total body muscle mass/fat-free mass was greater in controls (53%) than in AIDS wasting (43%; P = 0.04). Fasting whole body proteolysis and synthesis rates were increased above control in the HIV+ asymptomatic group and in the AIDS-wasting group ( P = 0.009). Whole body Leu oxidation rate was greater in the HIV+ asymptomatic group than in the control and AIDS-wasting groups ( P < 0.05). Fasting mixed muscle protein synthesis rate was increased in the asymptomatic subjects (0.048%/h; P = 0.01) but was similar in AIDS-wasting and control subjects (0.035 vs. 0.037%/h). Plasma Gln Rawas increased in AIDS-wasting subjects but was similar in control and HIV+ asymptomatic subjects ( P < 0.001). These findings suggest that AIDS wasting results from 1) a preferential reduction in muscle protein, 2) a failure to sustain an elevated rate of mixed muscle protein synthesis while whole body protein synthesis is increased, and 3) a significant increase in Gln release into the circulation, probably from muscle. Several interesting explanations for the increased Gln Rain AIDS wasting exist.

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A modelling study highlights the power of detecting and isolating asymptomatic or very mildly affected individuals for COVID-19 epidemic management

BMC Public Health ◽

10.1186/s12889-020-09843-7 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Lía Mayorga ◽

Clara García Samartino ◽

Gabriel Flores ◽

Sofía Masuelli ◽

María V. Sánchez ◽

...

Keyword(s):

Compartmental Model ◽

Reproduction Number ◽

Mitigation Measures ◽

Asymptomatic Group ◽

Healthcare Burden ◽

Fundamental Part ◽

Management Policies ◽

Asymptomatic Individuals ◽

The Impact ◽

The Ideal

Abstract Background Mathematical modelling of infectious diseases is a powerful tool for the design of management policies and a fundamental part of the arsenal currently deployed to deal with the COVID-19 pandemic. Methods We present a compartmental model for the disease where symptomatic and asymptomatic individuals move separately. We introduced healthcare burden parameters allowing to infer possible containment and suppression strategies. In addition, the model was scaled up to describe different interconnected areas, giving the possibility to trigger regionalized measures. It was specially adjusted to Mendoza-Argentina’s parameters, but is easily adaptable for elsewhere. Results Overall, the simulations we carried out were notably more effective when mitigation measures were not relaxed in between the suppressive actions. Since asymptomatics or very mildly affected patients are the vast majority, we studied the impact of detecting and isolating them. The removal of asymptomatics from the infectious pool remarkably lowered the effective reproduction number, healthcare burden and overall fatality. Furthermore, different suppression triggers regarding ICU occupancy were attempted. The best scenario was found to be the combination of ICU occupancy triggers (on: 50%, off: 30%) with the detection and isolation of asymptomatic individuals. In the ideal assumption that 45% of the asymptomatics could be detected and isolated, there would be no need for complete lockdown, and Mendoza’s healthcare system would not collapse. Conclusions Our model and its analysis inform that the detection and isolation of all infected individuals, without leaving aside the asymptomatic group is the key to surpass this pandemic.

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Estimated functional space of centric condyle positions in temporomandibular joints of asymptomatic individuals using MRI

Scientific Reports ◽

10.1038/s41598-019-52081-0 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Aleš Čelar ◽

André Gahleitner ◽

Stefan Lettner ◽

Josef Freudenthaler

Keyword(s):

Confidence Interval ◽

Functional Space ◽

Centric Relation ◽

Temporomandibular Joints ◽

Minimal Convex ◽

Mri Scans ◽

Confidence Ellipses ◽

Asymptomatic Individuals ◽

Asymptomatic Subjects

Abstract Magnetic resonance imaging (MRI) studies on centric condyle positions lack 3D comparisons of guided and unguided methods, which are used for accomplishing centric relation reference positions. The purpose of this study was to describe the space, in which mandibular condyles are placed in vivo by dental intercuspation, Dawson’s bimanual manipulation, and neuromuscular position. Twenty asymptomatic individuals aged 23 to 37 years underwent separate bite registrations using bimanual manipulation and the unguided neuromuscular technique. Subsequent 3-Tesla MRI scans of both temporomandibular joints yielded 3D data of the most superior condylar points at maximum intercuspation and both centric relation positions. We found concentric condyle positions in maximum intercuspation but considerable variation of condyle position after bimanual manipulation and neuromuscular technique. Their 95% predictive confidence ellipses overlapped substantially and created a space of reference positions. Its smallest volume averaged 2 mm3 for a minimal convex hull (95% confidence interval 1.1–3.2) and 3.5 mm3 for a minimal ellipsoid hull (95% confidence interval 1.8–5.4). Visualized in vivo by MRI, condyle positions at bimanual manipulation and neuromuscular position were not predictable and showed substantial variation in asymptomatic subjects. Clinicians should be aware of the functional space and its effect on dental intercuspation.

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The Natural History and Transmission Potential of Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infection

Clinical Infectious Diseases ◽

10.1093/cid/ciaa711 ◽

2020 ◽

Vol 71 (10) ◽

pp. 2679-2687 ◽

Cited By ~ 28

Author(s):

Nguyen Van Vinh Chau ◽

Vo Thanh Lam ◽

Nguyen Thanh Dung ◽

Lam Minh Yen ◽

Ngo Ngoc Quang Minh ◽

...

Keyword(s):

Natural History ◽

Severe Acute Respiratory Syndrome ◽

Rt Pcr ◽

Asymptomatic Group ◽

Transmission Potential ◽

Viral Loads ◽

Imported Cases ◽

History Of ◽

Asymptomatic Individuals ◽

A Prospective Study

Abstract Background Little is known about the natural history of asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Methods We conducted a prospective study at a quarantine center for coronavirus disease 2019 in Ho Chi Minh City, Vietnam. We enrolled quarantined people with reverse-transcription polymerase chain reaction (RT-PCR)–confirmed SARS-CoV-2 infection, collecting clinical data, travel and contact history, and saliva at enrollment and daily nasopharyngeal/throat swabs (NTSs) for RT-PCR testing. We compared the natural history and transmission potential of asymptomatic and symptomatic individuals. Results Between 10 March and 4 April 2020, 14 000 quarantined people were tested for SARS-CoV-2; 49 were positive. Of these, 30 participated in the study: 13 (43%) never had symptoms and 17 (57%) were symptomatic. Seventeen (57%) participants imported cases. Compared with symptomatic individuals, asymptomatic people were less likely to have detectable SARS-CoV-2 in NTS collected at enrollment (8/13 [62%] vs 17/17 [100%]; P = .02). SARS-CoV-2 RNA was detected in 20 of 27 (74%) available saliva samples (7 of 11 [64%] in the asymptomatic group and 13 of 16 [81%] in the symptomatic group; P = .56). Analysis of RT-PCR positivity probability showed that asymptomatic participants had faster viral clearance than symptomatic participants (P < .001 for difference over the first 19 days). This difference was most pronounced during the first week of follow-up. Two of the asymptomatic individuals appeared to transmit SARS-CoV-2 to 4 contacts. Conclusions Asymptomatic SARS-CoV-2 infection is common and can be detected by analysis of saliva or NTSs. The NTS viral loads fall faster in asymptomatic individuals, but these individuals appear able to transmit the virus to others.

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