An isothermal lab-on-phone test for easy molecular diagnosis of SARS-CoV-2 near patients and in less than 1 hour

OBJECTIVES

The performance of a new point-of-care CE-IVD-marked isothermal lab-on-phone COVID-19 assay was assessed in comparison to a gold standard real-time reverse transcriptase-PCR method.

METHODS

The study was conducted following a nonprobability sampling of ≥16-year-old volunteers from three different laboratories, using direct mouthwash (N = 24) or nasopharyngeal (N = 191) clinical samples.

RESULTS

The assay demonstrated 95.19% sensitivity and 100% specificity for detection of SARS-CoV-2 in direct nasopharyngeal crude samples and 78.95% sensitivity and 100% specificity in direct mouthwash crude samples. It also successfully detected currently predominant SARS-CoV-2 variants of concern (Beta B.1.351, Delta B.1.617.2, and Omicron B.1.1.529) and demonstrated to be inert against potential cross-reactions of other common respiratory pathogens that cause infections that present similar symptoms to COVID-19.

CONCLUSION

This lab-on-phone pocket-sized assay relies on an isothermal amplification of SARS-CoV-2's N and E genes, taking just 50 minutes from sample to result, with only 2 minutes of hands-on time. It presents good performance when using direct nasopharyngeal crude samples, enabling a low-cost, real-time, rapid, and accurate identification of SARS-CoV-2 infections at the point of care, which is important for both clinical management and population screening, as a tool to break the chain of transmission of COVID-19 pandemic, especially in low-resources environments.

Neutrophile-to-lymphocyte, lymphocyte-to-monocyte, and platelet-to-lymphocyte ratios as prognostic and response biomarkers for resectable locally advanced gastric cancer

BACKGROUND

Perioperative fluorouracil plus leucovorin, oxaliplatin, and docetaxel (FLOT) improves prognosis in locally advanced gastric cancer (LAGC). Neutrophil-to-lymphocyte (NLR), lymphocyte-to-monocyte (LMR), and platelet-to-lymphocyte (PLR) ratios are prognostic biomarkers but not predictive factors.

AIM

To assess blood ratios’ (NLR, LMR and PLR) potential predictive response to FLOT and survival outcomes in resectable LAGC patients.

METHODS

This was a multicentric retrospective study investigating the clinical potential of NLR, LMR, and PLR in resectable LAGC patients, treated with at least one preoperative FLOT cycle, from 12 Portuguese hospitals. Means were compared through non-parametric Mann-Whitney tests. Receiver operating characteristic curve analysis defined the cut-off values as: High PLR > 141 for progression and > 144 for mortality; high LMR > 3.56 for T stage regression (TSR). Poisson and Cox regression models the calculated relative risks/hazard ratios, using NLR, pathologic complete response, TSR, and tumor regression grade (TRG) as independent variables, and overall survival (OS) as the dependent variable.

RESULTS

This study included 295 patients (mean age, 63.7 years; 59.7% males). NLR was correlated with survival time (r = 0.143, P = 0.014). PLR was associated with systemic progression during FLOT (P = 0.022) and mortality (P = 0.013), with high PLR patients having a 2.2-times higher risk of progression [95% confidence interval (CI): 0.89-5.26] and 1.5-times higher risk of mortality (95%CI: 0.92-2.55). LMR was associated with TSR, and high LMR patients had a 1.4-times higher risk of achieving TSR (95%CI: 1.01-1.99). OS benefit was found with TSR (P = 0.015) and partial/complete TRG (P < 0.001). Patients without TSR and with no evidence of pathological response had 2.1-times (95%CI: 1.14-3.96) and 2.8-times (95%CI: 1.6-5) higher risk of death.

CONCLUSION

Higher NLR is correlated with longer survival time. High LMR patients have a higher risk of decreasing T stage, whereas high PLR patients have higher odds of progressing under FLOT and dying. Patients with TSR and a pathological response have better OS and lower risk of dying.

Therapeutic Vaccine against Streptococcus sobrinus-induced Caries

Streptococcus sobrinus produces a virulence-associated immunomodulatory protein (VIP) which suppresses the host-specific immune response and induces the early production of IL-10. In this study, we evaluated the effects of therapeutic immunization with this VIP on the incidence of caries in S. sobrinus-infected rats. Groups of Wistar rats were orally infected with S. sobrinus and fed with sucrose-sweetened drinking water ad libitum. Five days later, rats were immunized intranasally with active or heat-inactivated VIP plus alum as adjuvant or PBS plus adjuvant (sham-immunized). After 3 wks, all rats were re-immunized as above. Evaluation of dental caries showed that VIP-immunized animals had significantly fewer enamel sulcal and proximal caries lesions than did the sham-immunized animals (p < 0.001). The protective effects following therapeutic VIP immunization were attributed to the induced salivary immunoglobulin A specific to the VIP. These results offer a promising and safe strategy for the development of a vaccine against dental caries.

rEnolase maternal immunization confers caries protection on offspring

Therapeutic vaccination with Streptococcus sobrinus recombinant enolase (rEnolase) protects rats from dental caries. Here, we investigated the effect that maternal rEnolase vaccination before pregnancy had on the offspring's immune response to S. sobrinus oral infection and dental caries progression. Female Wistar rats were immunized by intranasal and subcutaneous routes with rEnolase adsorbed onto aluminum hydroxide as adjuvant or similarly treated with the adjuvant alone (sham-immunized). Ten days after the last administration, the immunized females were paired with a male rat. The oral immune responses to S. sobrinus infection and dental caries in the offspring were evaluated. The results showed that pups born from rEnolase-immunized mothers had higher levels of rEnolase-specific salivary IgA and IgG antibodies (indicating a placental antibody transfer) and lower sulcal and proximal enamel caries scores than rats born from sham-immunized mothers. In conclusion, rEnolase maternal immunization before pregnancy provides offspring with protection against S. sobrinus-induced dental caries.

[Aggressive angiomyxoma of the vulva]

An unusual myxoid and vascular appearing neoplasm of the vulva, termed an Aggressive Angiomyxoma, is described in two cases report. The clinical presentation and recurrence pattern were typical for previously described neoplasms of the same cellular pattern. The histopathology, difficulties in determining the surgical margins, and the treatment of this tumor are discussed.

Psychosocial consequences of nasal aesthetic and functional surgery: a controlled prospective study in an ENT setting

Much still needs to be known about what motivates and goes through patients' minds when undergoing nasal aesthetic surgery. Little is also known on how the aesthetic change affects the way other people see those patients after surgery, and if the improved appearance significantly benefits the patients' psychosocial functioning. So far, research has largely focused on subjects in Plastic Surgery settings, neglecting to investigate the specificities of rhinoplasty as performed by otolaryngologists. In order to elucidate these, a prospective controlled-study design was developed. Twenty-five consecutive patients, selected from an ENT practice for septorhinoplasty, were enrolled. They were submitted to pre-operative psychiatric interviews and psychological tests. Two control groups were simultaneously enlisted, and were submitted also to the same tests. Four to seven months after surgery, the septorhinoplasty patients were again evaluated by psychiatric interviews and psychological tests as well as asked to fill out a questionnaire addressing subjective satisfaction with the surgical results. They also underwent, at that time, a rhinomanometric examination assessing the objective success of surgery on nasal function. It was concluded that the study population was basically a psychologically well balanced group of patients, and that a successful surgical result could indeed, in some, improve pre-operative psychological "suffering" related to the nasal deformity, and give these patients a new social identity. Ultimately, it was found that the meeting of aesthetic requirements, frequently not put forward by the patient preoperatively, was the single most important factor required for a final complete satisfaction with the overall surgical results in this population.

Placental site trophoblastic tumour: the value of transvaginal colour and pulsed Doppler sonography (TV-CDS) in its diagnosis: case report

The clinical, transvaginal sonography and colour flow mapping of one patient with placental site trophoblastic tumour is presented. Colour Doppler documented a marked increase in uterine vascularity, characterised by low diastolic flow suggestive of low resistance blood flow, without regression after completion of apparently successful chemotherapy, when negative beta-hCG plasma levels were obtained. Surgical treatment was based upon our experience with colour Doppler assessment of gestational trophoblastic tumours and a review of the literature. This case suggests that TV-CDS, performed serially, is very useful in monitoring patients during chemotherapy and in detecting residual tumour, and should greatly increase the accurancy of diagnosis of PSTT.

Comparison of left ventricular ejection fraction in congenital heart disease by visual versus algorithmic determination

Two-dimensional (2D) echocardiographic visual estimation of left ventricular (LV) ejection fraction (EF) in patients with acquired heart disease yields results that are comparable to those obtained by recommended algorithms. However, there is no information concerning its accuracy in congenital heart disease. This study compares applicability, accuracy, and reproducibility of LVEF by visual estimation with that by currently used algorithms (cylinder hemiellipsoid, ellipsoid biplane, and biplane method of disks) in 92 consecutive patients with congenital heart disease but unrepaired complete atrioventricular septal defect, univentricular heart, and hypoplastic left ventricle, using 3D echocardiography as the reference method. Visual estimation of LVEF could be applied in all cases. Because of technically inadequate 2D echocardiographic images for volume measurement, analysis for comparison could be performed in 71 patients (77%), aged 1 day to 47 years. The correlation between 3D echocardiographic and visual estimation was 0.91 (SEE 3.3%), cylinder hemiellipsoid, 0.86 (SEE 3.9%), ellipsoid biplane 0.87 (SEE 3.9%), and biplane method of disks 0.93 (SEE 3.2%). Intraobserver variability was similar for all 2D echo methods. Interobserver variability was greater for visual estimation. In conclusion, visual estimation of LVEF is applicable to most patients with congenital heart disease, yielding results that are comparable to those obtained by currently used 2D echocardiographic algorithms.

Is mitral valve prolapse a congenital or acquired disease?

The prevalence of mitral valve prolapse (MVP) at birth was studied in 1,734 consecutive newborns without congenital structural heart disease. We have not identified any case of an unequivocal pattern of MVP using auscultatory and echocardiographic diagnostic criteria. Our data argue for the concept that MVP is an acquired disease.

Glutamate dehydrogenase deficiency in Machado-Joseph disease

We studied the activity of glutamate dehydrogenase (GDH) in leukocytes from 23 patients with dominantly inherited ataxia. All the patients were assessed with a rating scale for ataxias and met the clinical criteria for the diagnosis of Machado-Joseph disease. The mean age of onset of symptoms was 37.8, SD 13.4 years and the duration of the disease was 7.4, SD 4.9. Leukocyte GDH activity was significantly decreased (p < 0.001) when compared to 20 normal controls. These data extend previous reports indicating that a GDH deficiency is present in peripheral tissues from some patients with spinocerebellar degenerations. Furthermore, this study suggests that a genetic deficiency of GDH may underlie some forms of dominant ataxias; this deficiency may be marked in patients with Machado-Joseph disease and is not specific for any type of multiple system atrophy.

Dominantly inherited ataxias in Portugal

We analysed the clinical features of 82 patients with dominantly inherited ataxia in a cohort survey. All patients fulfilled the diagnostic criteria for Machado-Joseph disease. The mean age of onset of symptoms was 39.8 (+/- 12.5) years and the duration of the disease was 9.2 (+/- 6.7) years. Ataxia, peripheral neuropathy, and fasciculation scores correlated with age of onset and duration of disease. Upper motor neuron scores failed to correlate with age of onset. In a follow-up study we analysed the clinical data of 46 patients two years after the first examination. A paired t-test was used to compare differences between observations. The results are in agreement with those of the cross-section in time, suggesting a deterioration of the symptoms with the evolution of the disease. We conclude that dynamic definition of the disease according to age of onset and duration of symptoms is preferable to subdivision into classical types.

Homovanillic acid in the cerebrospinal fluid of Parkinsonian patients

Determinations of CSF HVA before and after Probenecid administration were made in 41 patients with Parkinson’s disease. The means of HVA concentration were lower than those of controls but no correlation with clinical data was found. A negative correlation was demonstrated between post-probenecid HVA levels and subsequent score improvement with L-DOPA at 3,6 and 12 months. Post-probenecid HVA levels suggest that there are distinct forms of parkinsonism and could predict the response to L-DOPA therapy.