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Corneal visualization Scheimpflug technology(Corvis ST)is currently the most commonly used clinical device for assessing in vivo corneal biomechanics. The new parameter stress-strain index(SSI)has been a hot topic of clinical research in recent years, which not only directly reflect corneal biomaterial stiffness, but also closely correlates with the progression of certain diseases. SSI was generated based on the predictions of corneal behavior using finite element(FE)numerical modeling to simulate the effects of intraocular pressure and Corvis ST jets. The SSI algorithm does not change with central corneal thickness(CCT), intraocular pressure, or biomechanically corrected intraocular pressure(BIOP), but it is clearly associated with altered collagen fibres in the corneosclera. The principles of SSI, the relationship between age and SSI, the relationship between axial length and SSI, the relationship between myopia and SSI, and the application of SSI are summarized and concluded.
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BACKGROUND Leishmaniases encompass a spectrum of neglected diseases caused by parasites of the genus Leishmania, grouped in two forms: tegumentary and visceral leishmaniasis. OBJECTIVES In this study, we propose Friend Virus B NIH Jackson (FVB/NJ) mouse strain as a new experimental model of infection with Leishmania (Leishmania) amazonensis, the second most prevalent agent of tegumentary leishmaniasis in Brazil. METHODS AND FINDINGS We performed in vitro infections of FVB/NJ macrophages and compared them with BALB/c macrophages, showing that BALB/c cells have higher infection percentages and a higher number of amastigotes/cell. Phagocytosis assays indicated that BALB/c and FVB/NJ macrophages have similar capacity to uptake parasites after 5 min incubations. We also investigated promastigotes' resistance to sera from FVB/NJ and BALB/c and observed no difference between the two sera, even though FVB/NJ has a deficiency in complement components. Finally, we subcutaneously infected FVB/NJ and BALB/c mice with 2 × 106 parasites expressing luciferase. Analysis of lesion development for 12 weeks showed that FVB/NJ and BALB/c mice have similar lesion profiles and parasite burdens. MAIN CONCLUSIONS This work characterises for the first time the FVB/NJ mouse as a new model for tegumentary leishmaniasis caused by Leishmania (L.) amazonensis.
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Purpose: To report age?related variations in corneal stress–strain index (SSI) in healthy Indians. Methods: It was a retrospective study where healthy Indian individuals aged between 11 and 70 years who had undergone corneal biomechanics assessment using Corvis ST between January 2017 and December 2021 were enrolled. Composite corneal biomechanical parameters and corneal SSI were abstracted from Corvis ST and compared across different age groups using one?way analysis of variance (ANOVA). Also, Pearson’s correlation was used to evaluate the association between age and SSI. Results: Nine hundred and thirty?six eyes of 936 patients with ages between 11 and 77 years with mean ± SD intraocular pressure (IOP) and pachymetry of 16.52 ± 2.10 mmHg and 541.13 ± 26.39 ?s, respectively. Composite corneal biomechanical parameters such as deformation amplitude ratio max at 1 mm (P < 0.001) and 2 mm (P < 0.001), biomechanically corrected IOP (P = 0.004), stiffness parameter at A1 (P < 0.001, Corvis biomechanical index (P < 0.018), and SSI (P < 0.001) were found to be significantly different as a function of age group. We noted a statistically significant positive association of SSI with age (P < 0.001), spherical equivalent refractive error (P < 0.001), and IOP (P < 0.001) and a significant negative association with anterior corneal astigmatism (P < 0.001) and Anterior chamber depth (ACD) (P < 0.001). Also, SSI was positively associated with SPA1 and bIOP, whereas negatively associated with integrated radius, max inverse radius, and Max Deformation amplitude (DA) ratio at 1 mm and 2 mm. Conclusion: We noted a positive association of corneal SSI with age in normal healthy Indian eyes. This information could be helpful for future corneal biomechanical research.
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Abstract Aim: To analyse the potential usefulness and clinical relevance of the assessment by echocardiography with left atrial strain, based on the myocardial atrial deformation curves with speckle-tracking velocity vector imaging (VVI), in the analysis of short-form recurrent atrial extra systoles in ambulatory patients not suffering from organic cardiopathy. Methods: We designed a descriptive, prospective, and observational study including 270 patients between the ages of 18 and 75 assessed during an outpatient cardiology consultation attended due to palpitations over a period of two years. Using ambulatory electrocardiographic monitoring, we selected cases with short forms of repetitive atrial extrasystole, isolated or recurrentatrial fibrillation and a control group formed by those patients without repetitive ectopia. All patients underwent a thorough echocardiographic study during their first cardiological visit. Results: The analysis of the dynamic curves segmental deformation generated after an atrial extrasystole can reveal different points of origin of the extrasystole and detect specific anatomical alterations in the interatrial conduction at the level of the Bachmann's fascicle showing different models of electro anatomical activation possibly involved in the appearance of repetitive forms. Higher values of dyssynchrony between the septal and lateral wall and elongation in the time of interatrial electromechanical conduction could also be related to the existence of repetitive ectopic beats. Conclusions: Our ambulatory study employing the left atrial longitudinal strain, particularly in its segmental analysis, provides new insights into its the usefulness and potential clinical relevance.
Resumen Objetivo: Analizar la utilidad y relevancia clínica de la evaluación mediante ecocardiografía basada en las curvas de deformación auricular miocárdica con imágenes vectoriales de velocidad (VVI) de speckle-tracking, en el análisis de las extrasístoles auriculares recurrentes de corta duración en pacientes ambulatorios sin cardiopatía orgánica. Métodos: Se diseñó un estudio descriptivo, prospectivo y observacional que incluyó a 270 pacientes de entre 18 y 75 años evaluados durante una consulta externa de cardiología a la que acudieron por palpitaciones durante un periodo de dos años. Mediante el uso de monitorización electrocardiográfica ambulatoria, se seleccionaron casos con formas cortas de extrasistolia auricular repetitiva, fibrilación auricular aislada o repetitiva y un grupo control formado por aquellos pacientes sin ectopia repetitiva. Todos los pacientes se sometieron a un estudio ecocardiográfico exhaustivo durante su primera visita cardiológica. Resultados: El análisis de las curvas dinámicas de deformación segmentaria generadas tras un extrasístole auricular diferentes modelos de activación electroanatómica posiblemente implicados en la aparición de formas repetitivas. Valores mayores de disincronía entre la pared septal y lateral y el alargamiento en el tiempo de conducción electromecánica intraauricular pudieran también relacionarse con la existencia de latidos ectópicos repetitivos. Conclusiones: Nuestro estudio ambulatorio empleando la deformación longitudinal auricular izquierda, particularmente en su análisis segmentario, proporciona nuevas perspectivas sobre su utilidad y potencial relevancia clínica.
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Purpose: The present work style and lifestyle have increased the digital device use. Therefore, an increase in digital eyestrain is to be expected. We undertook a survey during coronavirus disease 2019 (COVID?19) pandemic to investigate the practice of 20/20/20 rule and its association with digital device use and asthenopic symptoms. While this rule is commonly advised, little is known about its validity. Methods: An online survey form was disseminated through social media and emails. The questions for eye?related symptoms were similar to the convergence insufficiency symptom survey (CISS). Participants with age ?5 years were included, with parents completing the survey for children (?16 years). Results: A total of 432 participants (mean ± standard deviation [SD]: 26.06 ± 13.92 years) were enrolled, of which 125 responses were for children. The 20/20/20 rule was practiced only by 34% of the participants either regularly (n = 38) or occasionally (n = 109). Those who had complaints of burning sensation and headache tended to practice this rule. Among adult participants, more females (47%) practiced this rule when compared to males (23%). Also, adult females significantly (P = 0.04) had more symptoms score when compared to males. In children, no such gender difference was found. Conclusion: Only one?third of participants practice the 20/20/20 rule at least occasionally. More number of adult females being symptomatic and practicing in greater number could be due to higher prevalence of dry eye condition in females. While the symptom of burning sensation could be related to dry eye, that of headache could be related to refractive error or binocular vision dysfunctions
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Purpose: To know the magnitude and determinants of dry eye syndrome among health professionals and to study the correlation of computer vision syndrome with dry eye disease. Methods: In total, 501 participants took part in the study, which included history followed by baseline ocular examination, which included visual acuity using Snellen’s chart and anterior segment examination using a slit lamp. Later, a questionnaire was administered to health professionals to be filled out for analysis in the present study. Results: The symptoms reported occasionally were burning (35.5%), itching (34.5%), foreign body sensation 22.6%, and tearing (35.3%). The majority of participants used mobiles and laptops (56.1%) as a display. Also, 53.3% of participants have heard about dry eye syndrome, and the source of information was from friends and doctors in 17% of participants. One hundred twenty?one participants (24.2%) had taken the consultation for ocular symptoms. Eighty?six participants had mild, 29 participants had moderate, and 6 participants had severe dry eye disease, respectively. Conclusion: The pandemic effect, and the drastic shift of educational media from the classroom to the digital platform have increased the use of mobiles, laptops, or other digital pads for learning. This has increased the risk for health professionals.
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Abstract Right ventricular longitudinal strain (RVLS) is frequently used as a measure of right ventricular systolic function. Abnormal RV strain is associated with poor prognosis in patients with pulmonary hyper tension (PH); however, the measure is not always easy to obtain in patients with poor apical acoustic windows. Objective: This study aims to analyze the RVLS and determine if there is a difference when measured from the apical and subcostal views. Methods: In this cross-sectional study, we analyzed 22 adult outpatients (≥ 18 years old), 81% female, mean age 49.9 ± 17.3 years, with a diagnosis of PH using right heart catheterization, followed from January 2016 to January 2020. Results: RVLS measured in the RV free wall from the apical views was -15% (-19% to -10%) and subcostal views -14.5% (-18% to -11%) were highly correlated (Person's r = 0.969, p < 0.0001). Segment by segment analysis did not show significant differences either: basal four-chamber vs. sub costal view was -16.5% (-21% to -11%) vs. -15.5% (-20% to -11%), p = 0.99, mid four-chamber view vs. subcotal view was -16.5% (-21% to -12%) vs. -16.5% (-20% to -11%), p = 0.87, apical four-chamber view vs. subcostal view was -12% (-18% to -8%) vs. -13.5% (-19% to -10%), p = 0.93. Conclusion: Subcostal RVLS free wall is a feasible and accurate alternative to conventional RVLS free wall from the apical view in patients with pulmonary hypertension and could be useful in patients with poor acoustic apical four-chamber windows.
Resumen El strain longitudinal del ventrículo derecho (SLVD) permite medir la función sistólica del ventrículo derecho (VD). La disminución del strain (deformación) del VD se asocia con mal pronóstico en pacientes con hipertensión pulmonar (HP), pero no siempre es fácil de obtener en pacientes con mala ventana acústica apical. Objetivo: Este estudio tiene como objetivo analizar el SLVD y determinar si las vistas apical y subcostal son comparables. Métodos: En este estudio transversal, se incluyeron 22 pacientes adultos ambulatorios (≥18 años), 81% mujeres, edad promedio 49.9 ± 17.3 años, con diagnóstico de HP mediante cateterismo cardíaco derecho, seguidos desde enero de 2016 hasta enero de 2020. Se midió la deformación de la pared libre del ventrículo derecho desde las vistas de cuatro cámaras apical y cuatro cámaras subcostal. Resultados: El SLVD medido en la pared libre del VD desde la vista apical fue -15% (-19% a -10%) vs. -14.5% (-18% a -11%) cuando se midió desde la vista subcostal (p = 0,99). El análisis segmento por s egmento tampoco mostró diferencias significativas: el segmento basal apical vs. subcostal fue -16.5% (-21% a -11%) vs. -15.5% (-20% a -11%), p = 0.99, el segmento medio apical vs. la vista subcotal fue -16.5% (-21% a -12%) vs. a -16.5% (-20% a -11%), p = 0.87, el segmento apical vs. la vista subcostal fue -12% (-18% a -8%) frente a -13.5% (-19% a -10%), p = 0.93. Conclusión: En pacientes con HP, el SLVD obtenido en la pared libre subcostal es una alternativa útil en los casos con ventana acústica apical subóptima.
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Purpose: To examine the role of the strain ratio in elastosonography for the differential diagnosis of common intraocular tumors such as choroidal melanoma, choroidal hemangioma, choroidal metastatic carcinoma, and retinoblastoma. Methods: This study included patients suffering from intraocular space?occupying lesions and who visited Beijing Tongren Eye Center of Beijing Tongren Hospital affiliated to Capital Medical University from June 2016 to March 2020. All patients underwent a physical examination, fundus examination with mydriasis, color Doppler ultrasonography, elastosonography, magnetic resonance imaging (MRI), and fundus angiography within 1 week. All patients were grouped as choroidal melanoma, choroidal metastatic carcinoma, retinoblastoma, choroidal hemangioma, and optic disk melanocytoma. A receiver operating characteristic (ROC) curve analysis was performed to assess the strain ratio for diagnosing malignant intraocular tumors. Results: A total of 155 patients (161 eyes) were recruited. The strain ratios measured were 39.59 ± 15.92 for choroidal melanoma, 36.85 ± 13.64 for choroidal metastatic carcinoma, 38.93 ± 17.27 for retinoblastoma, 13.42 ± 10.93 for choroidal hemangioma, and 3.84 ± 1.32 for optic disk melanocytoma. The strain ratios of the three malignant lesions were significantly higher than those of the two benign lesions (all P < 0.001). The area under the ROC curve was 0.95 ± 0.028. The optimal cutoff point was 22.67, with 85.7% sensitivity and 96.4% specificity. Conclusion: There were significant differences in elasticity between the malignant and benign intraocular tumors. The strain ratio using elastosonography could serve as an important auxiliary examination to distinguish between benign and malignant intraocular tumors
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Abstract Although Staphylococcus aureus increases its relative abundance in psoriasis when compared with the microbiome of healthy subjects, it is not the most important microorganism underlying this disease. However, there is scant data on the role and molecular features of S. aureus strains in psoriasis; therefore, the aim of this study was to evaluate nasal carriage of this microorganism, its phenotypic and molecular characteristics as well as the impact of host factors on its carriage in psoriatic patients. The presence of S. aureus was analyzed in nasal swabs from 46 healthy volunteers and 50 psoriatic patients by conventional microbiology techniques. Nasal carriage of S. aureus was higher in psoriatic patients than in the control group (37.24% vs 22.98%, respectively), being associated to sex (male), age (adults) and severity of the disease (more frequent in moderate and severe cases). Determination of antibiotic resistance detected 12% of (-lactam resistant isolates, with variable accompanying resistance to macrolides, aminoglycosides and fluoroquinolones. No resistance to rifampicin, vancomycin, mupirocin or trimethoprim/sulfamethoxazole was found. A preliminary molecular characterization of the isolates was performed by PCR amplification of virulence genes. Molecular characterization of the strains did not reveal a predominant strain in psoriatic patients. Although we established host factors related to increased carriage of S. aureus in psoriatic patients, we could not establish the predominance of one type of strain. Genomic and transcriptomic analysis of the isolated strains would be necessary to address this point.
Resumen A pesar de que Staphylococcus aureus incrementa su abundancia relativa en la psoriasis cuando se compara con el microbioma de personas sanas, no es el microorganismo más importante subyacente a la enfermedad. Sin embargo, existen pocos datos sobre el papel y las características moleculares de las cepas de S. aureus en pacientes con psoriasis. Nuestro objetivo fue evaluar la portación nasal de este microorganismo, sus características fenotípicas y moleculares, y el impacto de factores del hospedador sobre dicha portación en estos pacientes. Se analizó la presencia de S. aureus en hisopados nasales de 46 voluntarios sanos y 50 pacientes con psoriasis mediante técnicas microbiológicas convencionales. Se encontró mayor portación en pacientes con psoriasis que en el grupo control (37,24% vs. 22,98%, respectivamente) y esta estuvo asociada al sexo (masculino), la edad (adultos) y la gravedad de la enfermedad (más frecuente en casos moderados a graves). El 12% de los aislamientos de S. aureus mostraron resistencia a betalactámicos, con resistencia acompañante a macrólidos, aminoglucósidos y fluoroquinolonas en grado variable. No se encontró resistencia a rifampicina, vancomicina, mupirocina o trimetroprima/sulfametoxazol. Se realizó una caracterización molecular preliminar de los aislamientos por amplificación de genes de virulencia mediante PCR. Si bien se identificaron factores relacionados con el hospedador que incrementan la portación nasal de S. aureus en pacientes con psoriasis, la caracterización molecular de las cepas no reveló ninguna característica genotípica predominante asociada a esta afección. Se necesitan más estudios genómicos y transcriptómicos para profundizar en esta caracterización.
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Right ventricular (RV) pacing is associated with a reduction in left ventricular (LV) systolic function, thought to be mediated by pacing-induced ventricular dyssynchrony. The prevalence of heart failure after RV pacing is reported to range from 31±3%. We studied 60 subjects with high-grade atrioventricular block and Complete Heart Block (CHB) scheduled to undergo right ventricular apical pacing. 2D echocardiography was done at baseline, 1 month and 12 months. Pacing-induced cardiomyopathy was defined as a reduction in LVEF to <45%. Strain was evaluated off-line from digitally stored images using all advanced software package (cardiac wall motion quantification (CMQ); Toshiba Medical Systems). Longitudinal strain for individual myocardial segments was measured from the apical four-chamber, two-chamber and long axis views (16 segment AHA/ASE model). None had LV dysfunction at baseline based on 2D and strain echo imaging. Subsequently 18 patients were detected to develop low GLS score (less than -14.5) at 1 month. On subsequent follow up at 1 year, all 18 patients developed LV dysfunction on 2D Echocardiography. Thus Strain imaging with GLS score helped in early detection of LV dysfunction in RV apical pacing subjects. Pacing-induced cardiomyopathy had significant association with high grade AV block with pacemaker dependency. It had no significant associations with other comorbidities like diabetes, hypertension, ischemic heart disease or with the type of medication intake. However there was a statistically significant association with heart failure
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@#Objective To develop and verify a sandwich ELISA method with bovine polyclonal antibody against rabbit polyclonal antibody for the determination of D antigen content of Sabin strain inactivated poliovirus vaccine(sIPV).Methods The rabbit polyclonal antibodies were prepared with sIPV vaccine bulks of type Ⅰ,Ⅱ and Ⅲ as antigens and detected for the titer and specificity by indirect ELISA.A double antibody sandwich ELISA with bovine polyclonal antibody as coating antibody and rabbit polyclonal antibody as detection antibody was developed to determine D antigen content,and the accuracy,precision and specificity to D antigen of the method were verified.sIPV vaccine samples from five domestic enterprises were detected by the developed method.Results The rabbit polyclonal antibodies for type Ⅰ,Ⅱ and Ⅲ sIPV with good specificity and high titer were prepared,and the double antibody sandwich ELISA method was successfully developed.Using four-parameter fitting,all three standard curves showed good linear relationship,and R~2 values were more than 0.99.The spike recoveries of type Ⅰ,Ⅱ and Ⅲ D antigens were all within 80%～120%,with average values of98.11%,97.41% and 98.66%,respectively.The CVs of repeatability and intermediate precision were all below 10%.The method also distinguished D antigens from C antigens.The developed method determined the D antigen contents of sIPV vaccines from five enterprises.Conclusion A sandwich ELISA method for determination of D antigen content in sIPV vaccine was successfully developed with satisfying accuracy,precision and certain D antigen specificity,which can be used to detect vaccines produced by different manufacturers.
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@#Objective To evaluate the passage stability of H5N1(NIBRG-14) influenza virus vaccine strain in MDCK cells(sMDCK)of serum-free suspension culture.Methods H5N1(NIBRG-14) influenza virus working-bank vaccine strains were passed 15 consecutive times in sMDCK cells.The 8-segment nucleotide sequences(HA,NA,M,NP,NS,PA, PB1 and PB2 genes) of the main-bank,working-bank,virus of P1,P2,P3,P5,P10 and P15 generations were detected for genetic stability by second and first generation sequencing.The stability of amino acid sequences of hemagglutinin(HA)and neuraminidase(NA),the main antigens of the working-bank,P5 and P15 generation viruses,were evaluated by using peptide coverage as indicators;Influenza vaccine was prepared with working-bank,P5 and P15 generation viruses,with which the female BALB/c mice were immunized i.m.with 10 in each group,15 μg HA per mouse,and boosted 28 d later at the same dosage and route.At 28,42 and 56 d after the primary immunization,the mice were detected for the titer of neutralizing antibody in serum to evaluate the stability of immunogenicity.Results No segment insertion or deletion was detected in each generation of influenza virus,and the nucleotide sequence was completely consistent with the main-bank;Single nucleotide polymorphism(SNP) mutations did not occur in the main-bank,working-bank,P1,P2,P3,P5 and P10 generations of viruses,while the possibility of SNP mutation showed in many gene loci of P15 generation virus,with heterozygous SNP accounting for 91.62%.The coverage rate of HA and NA protein peptides of P5 and P15 generation viruses ranged from96.7% to 100%.There was no significant difference in serum neutralizing antibody titer of mice in the working-bank,P5 and P15 groups(H=2.253,2.029 and 1.408,P=0.324,0.363 and 0.495,respectively) at 28,42 and 56 d after the first immunization.Conclusion H5N1(NIBRG-14) influenza virus vaccine strain has good genetic stability in sMDCK cells,which is expected to be used in the production of sMDCK cell matrix pandemic influenza vaccine.
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@#Objective To compare the sensitivity(dilution) of antigen-detecting rapid diagnostic cards for severe acute respiratory symptom coronavirus 2(SARS-CoV-2) at home and abroad to different strains.Methods Vaccine bulks of four SARS-CoV-2 strains(original strain,Beta,Delta and Omicron) produced by Wuhan Institute of Biological Products Co.,Ltd.were used as the sample panel for sensitivity assessment,of which a series of diluted samples were detected by using 21 batches of SARS-CoV-2 antigen-detecting rapid diagnostic cards from 17 domestic and foreign manufacturers and SARS-CoV-2 nucleic acid detection reagent from Shanghai GeneoDx Biotech Co.,Ltd,respectively.The sensitivity of antigendetecting rapid diagnostic cards and nucleic acid detection reagent was evaluated according to the dilutions.The results of SARS-CoV-2 antigen-detecting rapid diagnostic reagents and nucleic acid detection reagent were compared to determine the nucleic acid detection Ct value corresponding to the group of antigen-detecting rapid diagnostic reagent with the highest dilution,namely the highest sensitivity.Results The sensitivity of antigen detection cards for the vaccine bulks of original strain,Beta,Delta and Omicron was 1:10～1:8 × 10~4.1:10~3～1:2 × 10~5,1:10~2～1:4 × 10~4,and 1:10～1:4 × 10~5,respectively;The sensitivity of nucleic acid detection cards was 10~(-6),10~(-5),10~(-4) and 10~(-7),respectively.The Ct values of N gene which were reached by high sensitivity antigen-detecting rapid diagnostic cards were as follows:original strain(10~(-4)) of more than 31,Beta variant(10~(-5)) of more than 36,Delta variant(10~(-4)) of more than 34,Omicron variant(10~(-5)) of more than 33,meeting the requirements of domestic and European Union for SARS-CoV-2 antigen-detecting rapid diagnostic cards.Conclusion All the antigen-detecting rapid diagnostic cards detected the four virus strains,while the sensitivity of different reagents to different variants varies to some extent,among which the sensitivity to Omicron variant varies the most.
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@#Objective To analyze the etiology of clinical cases of live attenuated varicella vaccine.Methods 64 samples of varicella vesicle fluid from 49 patients clinically diagnosed as varicella cases in phase Ⅲ clinical trial of live attenuated varicella vaccine in enterprises(the test site was Henan Province) were collected,extracted for DNA,and distinguished for wild-type strains and vaccine strains by PCR and restriction fragment length polymorphism(PCR-RFLP).Genotype was analyzed using the genotyping method recommended at the international(varicella-zoster virus,VZV) nomenclature meeting2008.Results 64 vesicle fluids were all wild-type strains(Pst Ⅰ~+Sma Ⅰ~-BssH Ⅱ~-Nae Ⅰ~-),and no vaccine-related cases occurred.All 49 isolates belonged to Clade 2.Additionally,compared with Clade 2,a synonymous mutation(T→C) in SNP18 082 was detected in all 49 isolates,and a mutation(C→A) in SNP790 was detected in one isolate.Conclusion In the clinical trial of live attenuated varicella vaccine in Henan Province,all the clinical cases were caused by infection of wild-type strain which belonged to Clade 2 genetic branch.
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Influenza viruses are common pathogens causing respiratory infections in humans. Among the four seasonal influenza viruses, influenza A virus H3N2 has become the leading cause of seasonal influenza illness and death, posing a great threat to public health and the economy. Since it first emerged and caused a pandemic in 1968, H3N2 has been circulating repeatedly in human beings and continually evades host immune attack by antigenic drift, resulting in a decrease in vaccine efficacy. In this paper, the antigenic evolution of influenza A virus H3N2, the impact of antigenic evolution on the selection of vaccine strains and some models for predicting the evolution of influenza viruses were analyzed and reviewed, which paved the road for understanding the antigenic evolution of influenza virus and vaccine development.
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Objective:To investigate the relationship between carotid atherosclerosis(CAS)and subclinical left ventricular(LV)dysfunction in type 2 diabetes mellitus patients with preserved LV ejection fraction(LVEF).Methods:A total of 120 patients with type 2 diabetes mellitus who had LVEF≥50% were selected in the Department of Endocrinology, the First Affiliated Hospital of Air Force Medical University from June 2021 to October 2021. The global longitudinal strain(GLS)was obtained by two-dimensional speckle tracking echocardiography(STE)to assess subclinical LV systolic function. The mitral ratio of peak early to late diastolic filling velocity(E/A), and mitral velocity to early diastolic velocity of the mitral annulus(E/E′)ratio were obtained by pulsed tissue Doppler echocardiography to assess LV diastolic function. Acrroding to bilateral carotid ultrasound examination, the subjects were divided into normal carotid arteries group( n=46) and CAS group( n=74). Demographics and biochemical parameters were compared between two groups. Binary logistic regression and Pearson correlation analysis were used to evaluate the relationship between CAS and subclinical LV dysfunction. Results:The CAS group had a higher proportion of men, older age, and a longer duration of diabetes than the normal carotid arteries group(all P<0.05). There was no difference in LVEF and GLS between the two groups [normal carotid arteries group vs CAS group, LVEF: (60.72±4.73)% vs(60.07±4.28)%; GLS: (18.24±3.72)% vs(17.81±3.47)%, respectively; both P>0.05]. However, compared with normal carotid arteries group, E/A ratio was decreased and E/E′ ratio was significantly increased in CAS group(both P<0.01). Pearson correlation analysis showed that GLS was not correlated with carotid plaque thickness and carotid intima-media thickness(CIMT; both P>0.05). By contrast, E/E′ ratio was positively correlated with carotid plaque thickness and CIMT(both P<0.05). Binary logistic regression analysis showed that GLS and E/E′ ratio were not associated with CAS( both P>0.05). However, decreased E/A ratio was significantly associated with the existence of CAS( OR=0.09, 95% CI 0.01-0.67, P=0.018). Conclusions:In type 2 diabetes mellitus patients without overt heart failure and with preserved LVEF, the occurrence of CAS is not associated with subclinical LV systolic impairment assessed by GLS, but is significantly associated with LV diastolic dysfunction, and is independent of traditional cardiovascular risk factors.
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Objective:To explore the difference of the vessel and plaque characteristics, myocardial perfusion and cardiac function between patients with ischemia with non-obstructive coronary artery disease (INOCA) and obstructive coronary artery disease (CAD).Methods:From July 2021 to June 2022, 101 patients with angina were referred to dynamic computed tomography myocardial perfusion (CTP) and coronary computed tomography angiography (CCTA) and retrospectively included in our hospital. Based on the results of CTP and CCTA, patients were divided into INOCA (27 cases), moderate obstructive CAD (26 cases) and severe obstructive CAD (48 cases). The anatomical coronary artery stenosis, plaque characteristics and myocardial perfusion features of all patients were analyzed. Furthermore, left ventricular global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were obtained on full-phase reconstruction CCTA image by using Medis Suite 3.2 postprocessing software. Multigroup analysis used one way ANOVA or Kruskal Wallis H test. Results:Patients with INOCA were younger than patients with moderate and severe obstructive CAD ( P<0.001). INOCA patients (7.4%, 2/27) had lower rate of positive remodeling than both moderate (57.7%, 15/26, P<0.001) and severe obstructive CAD patients (33.3%, 16/48, P=0.017). The percentage of ischemic myocardium volume in patients with INOCA were similar with those in patients with severe CAD (all P>0.05), but significantly higher than those in patients with moderate CAD (all P<0.05). No significant difference in terms of GLS was detected between patients with INOCA [-17.4% (-21.6%, -11.6%)] and severe CAD [-17.6% (-21.9%, -14.8%), P=0.536], however, patients both with INOCA and severe CAD also had higher GLS than patients with moderate obstructive CAD [-22.3% (-29.8%, -19.0%), all P<0.05]. Conclusions:Based on"one-stop-shop"CTP combined with CCTA imaging, early cardiac functional changes including abnormal myocardial perfusion and myocardial strain in INOCA patients were similar to those in patients with severe obstructive CAD and more severe than those in patients with moderate obstructive CAD.
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Objective:To investigate the clinical application value of left ventricular myocardial strain obtained by cardiac MR (CMR) in recent major adverse cardiovascular events (MACE) in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).Methods:From January 2020 to December 2020, a total of 163 patients successfully underwent primary PCI and underwent CMR examination within one week after surgery at Affiliated Hospital of Xuzhou Medical University. The scan sequences included rapid balance-fast field echo and late-gadolinium enhancement. CVI42 post-processing software was used to analyze and measure the left ventricular myocardial strain indices, including left ventricular global longitudinal strain (GLS), left ventricular global circumferential strain (GCS), and left ventricular global radial strain (GRS). According to the results of the 1-year follow-up after surgery, the patients were divided into the MACE group ( n=28) and the non-MACE group ( n=135). For continuous variables with a normal distribution, the t test of two independent samples was used for comparisons between groups. For continuous variables with an abnormal distribution, the variables were compared and analyzed by the rank sum test. For categorical variables, the χ 2 tests were used for between-group comparisons. Cox regression was used to analyze the prognostic value of myocardial strain on the development of MACE in patients with STEMI. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficacy of myocardial strain parameters, and the optimal cut-off value was evaluated by calculating the Youden index. Results:The GLS, GCS, and GRS of the MACE group were (-10.4±3.3)%, [-11.9 (-14.5, -9.3)]%, and (18.3±6.3)%, respectively, and those of the non-MACE group were (-13.7±3.4)%, [-14.6 (-16.4, -11.7)]%, and (22.3±6.1)%, respectively. The difference between the two groups was statistically significant ( t/ Z=-4.71, -3.04, 3.21, P<0.05). Multivariate Cox regression analysis showed that GLS was an independent predictor of MACE (HR=1.546, 95%CI 1.180-2.027, P=0.002). The ROC curve analysis showed that GLS had the largest area under the curve (AUC) (AUC=0.754, 95%CI 0.658-0.851, P<0.001), with a cut-off value of -12.45%. Its diagnostic sensitivity was 71.4%, and the specificity was 67.4%. The value was better than that of the traditional predictor of STEMI prognosis, namely, left ventricular ejection fraction (AUC=0.680, 95%CI 0.567-0.793, P=0.003). Conclusion:GLS of CMR is an independent predictor of MACE in STEMI patients undergoing primary PCI.
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Objective:To analyze the late gadolinium enhancement (LGE) manifestations, cardiac function, and myocardial strain by feature tracking (FT) in Takayasu arteritis (TA) with pulmonary artery involvement (PTA) using cardiac MR (CMR), and then to investigate manifestations of the impaired myocardial structure and function.Methods:A retrospective study was performed on 32 patients with PTA and 21 healthy subjects without cardiopulmonary diseases from January 2017 to December 2020. All of them underwent CMR examinations. According to the presence of pulmonary arterial hypertension (PAH),PTA patients were divided into two groups including PAH group (11 cases) and non-PAH group (21 cases). LGE manifestations were observed and Fisher exact test was used for statistical analysis between the two groups. Cardiac function parameters and FT values including global peak strain of the left and right ventricle were calculated separately in PAH, non-PAH group of patients and healthy controls, using One-way ANOVA or non-parametric Kruskal-Wallis test for statistical analysis including a pairwise comparison between groups. The correlations between FT values of the PAH group and parameters measured by right heart catheterization test (RHC) and transthoracic echocardiography were analyzed using Pearson or Spearman correlation analysis.Results:There were 23 PTA patients (71.9%) with LGE. LGE in the interventricular insertion points (IPs)(11/11), and in the mid-wall (11/11) or epicardial (10/11) myocardium was more common ( P values were 0.006,<0.001 and 0.011, respectively) in PAH group, compared with LGE in the IPs (11/21), and in the mid-wall (7/21) or epicardial (9/21) myocardium in non-PAH group. The absolute values of left ventricular global peak circumferential strain (LVGPCS), left ventricular global peak longitudinal strain (LVGPLS) and right ventricular global peak longitudinal strain in PAH group were smaller than those in healthy subjects ( P<0.05). The absolute values of LVGPCS and LVGPLS in non-PAH group were smaller than those in healthy subjects ( P<0.05). In PAH group, mean pulmonary artery pressure of RHC was correlated with several FT parameters ( P<0.05), especially left ventricular global peak radial strain ( r=-0.807, P=0.009) and LVGPCS ( r s=0.817, P=0.007). Conclusions:Myocardial injury can be seen in PTA patients. And LGE in the IPs and LGE in the mid-wall or epicardial myocardium is more common in PTA patients with PAH. LVGPCS and LVGPLS can early indicate left heart dysfunction in PTA patients without PAH.
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Objective:To investigate the effect of mid-ventricular obstruction (MVO) on left ventricular systolic function in patients with hypertrophic cardiomyopathy(HCM) by four-dimensional automatic left ventricular quantitation technology(4D Auto LVQ).Methods:Fifty-seven hypertrophic obstructive cardiomyopathy patients were selected from December 2020 to October 2022 in the First Affiliated Hospital of Zhengzhou University. According to the presence of MVO, HCM patients were divided into two groups: HCM 1 group, HCM without MVO ( n=34); HCM 2 group, HCM with MVO ( n=23). In addition, 25 healthy subjects in the same period were selected as the control group. Conventional ultrasound parameters were collected, and 4D Auto LVQ technology was used to obtain the mechanical parameters of left ventricular myocardium, including left ventricular longitudinal strain (GLS), circumferential strain (GCS), area strain (GAS), radial strain (GRS), segmental longitudinal strain (SLS) and area strain (SAS). The differences of these parameters among the three groups were compared. Results:①Compared with the control group, the thickness of the maximum basal segment of interventricular septum, the thickness of the middle segment of the maximum interventricular septum, the thickness of the apical segment of the interventricular septum, the thickness of the left ventricular posterior wall and left atrium diameter were significantly increased. Six-minute walk distance and the left ventricular end-diastolic diameter was decreased in the two groups of HCM(all P<0.05). Left ventricular outflow tract gradients in HCM 1 group was higher than HCM 2 group( P<0.05), but there was no significant difference in left ventricular ejection fraction among the three groups( P>0.05). There was significant difference in the incidence of left ventricular apical aneurysm among the three groups( P<0.05). ②Compared with the control group, the GLS in both HCM groups was lower, and it was lower in the HCM 2 group than in the HCM 1 group(all P<0.05) the GRS and GAS in both HCM groups were lower than in the control group ( P<0.05), and there was no significant difference between the two groups of HCM, and there was no significant difference in GCS among the three groups(all P>0.05). ③Compared with the control group, the SLS of basal segment, middle segment, apical cap, posterior septum, inferior wall and lateral wall in HCM group were significantly lower than those in control group. The SLS of apical segment of posterior septum, anterior septum, anterior wall, posterior wall, inferior wall and apical segment of posterior septum, lateral wall and inferior wall in HCM 2 group were significantly lower than HCM 1 group(all P<0.05), but there was no significant difference in SLS of posterior septum, anterior septum, anterior wall, lateral wall and inferior wall between the two groups(all P>0.05). ④Compared with the control group, the SAS of posterior septal basal segment, middle segment, anterior septal middle segment, anterior wall basal segment, middle segment, apical segment, lateral wall basal segment, middle segment, apical segment, posterior wall basal segment, middle segment, inferior wall basal segment, middle segment and apical cap in HCM groups were significantly lower than the control group(all P<0.05), but there was no significant difference in SAS between the two groups of HCM( P>0.05). Conclusions:4D Auto LVQ can quantitatively evaluate the damage of MVO on the left ventricular systolic function in patients with HCM, especially for the evaluation of local myocardial function damage in the medial segment and apical segment.