Sickle cell disease (SCD) is a group of common, life-threatening disorders caused by a point mutation in the β globin gene. Early diagnosis through newborn and early childhood screening, parental education, and preventive treatments are known to reduce mortality. However, the cost and complexity of conventional diagnostic methods limit the feasibility of early diagnosis for SCD in resource-limited areas worldwide. Although several point-of-care tests are commercially available, most are antibody-based tests, which cannot be used in patients who have recently received a blood transfusion. Here, we describe the development of a rapid, low-cost nucleic acid test that uses real-time fluorescence to detect the point mutation encoding hemoglobin S (HbS) in one round of isothermal recombinase polymerase amplification (RPA). When tested with a set of clinical samples from SCD patients and healthy volunteers, our assay demonstrated 100% sensitivity for both the β A globin and β S globin alleles and 94.7 and 97.1% specificities for the β A globin allele and β S globin allele, respectively ( n = 91). Finally, we demonstrate proof-of-concept sample-to-answer genotyping of genomic DNA from capillary blood using an alkaline lysis procedure and direct input of diluted lysate into RPA. The workflow is performed in <30 min at a cost of <$5 USD on a commercially available benchtop fluorimeter and an open-source miniature fluorimeter. This study demonstrates the potential utility of a rapid, sample-to-answer nucleic acid test for SCD that may be implemented near the point of care and could be adapted to other disease-causing point mutations in genomic DNA.

The global COVID-19 pandemic has highlighted the need for rapid, accurate and accessible nucleic acid tests to enable timely identification of infected individuals. We optimized a sample-to-answer nucleic acid test for SARS-CoV-2 that provides results in <1 hour using inexpensive and readily available reagents. The test workflow includes a simple lysis and viral inactivation protocol followed by direct isothermal amplification of viral RNA using RT-LAMP. The assay was validated using two different instruments, a portable isothermal fluorimeter and a standard thermocycler. Results of the RT-LAMP assay were compared to traditional RT-qPCR for nasopharyngeal swabs, nasal swabs, and saliva collected from a cohort of patients hospitalized due to COVID-19. For all three sample types, positive agreement with RT-LAMP performed using the isothermal fluorimeter was 100% for samples with Ct <30 and 69–91% for samples with Ct <40. Following validation, the test was successfully scaled to test the saliva of up to 400 asymptomatic individuals per day as part of the campus surveillance program at Rice University. Successful development, validation, and scaling of this sample-to-answer, extraction-free real-time RT-LAMP test for SARS-CoV-2 adds a highly adaptable tool to efforts to control the COVID-19 pandemic, and can inform test development strategies for future infectious disease threats.

Existen escasos estudios sobre la forma de evaluar el proceso sensorial en adultos; una de estas formas es el uso de perfil sensorialdesarrollado por Brown y Dunn en el año 2002, aplicable tanto para la población infantil como adulta de habla inglesa. Hasta el momentono existe una evaluación de procesamiento sensorial del adulto validada en castellano. En base a estos antecedentes, el principal objetivo deeste estudio es validar la construcción interna de una escala de procesamiento sensorial en el adulto a través del Cuestionario del ProcesoSensorial del Adulto (CPSA) con una población de habla hispana, para luego comparar los resultados con la misma prueba anteriormentevalorada en una población de habla inglesa. Los pasos en la elaboración de esta prueba fueron los siguientes: 1) traducción de la prueba alcastellano; 2) instalación de la prueba en Internet e invitación a responderla; 3) análisis de los resultados usando estadísticas descriptivasy análisis de factores para observar diferencias con los factores desarrollados con las personas de habla inglesa y 4) comparación entre losfactores obtenidos en la prueba con población hispana y con población de habla inglesa.Se dieron 11 factores que representan hipo o hiper respuesta en los sistemas sensoriales analizados. Estos factores se asemejan alos factores obtenidos con la población de habla inglesa. Esta prueba puede utilizarse para pesquisar dificultades de procesamientosensorial de adultos en base a los resultados obtenidos

Frequent and accessible testing is a critical tool to contain the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To develop low-cost rapid tests, many researchers have used reverse transcription loopmediated isothermal amplification (RT-LAMP) with fluorescent readout. Fluorescent LAMP-based assays can be performed using cost-effective, portable, isothermal instruments that are simpler to use and more rugged than polymerase chain reaction (PCR) instruments. However, false-positive results due to nonspecific priming and amplification have been reported for a number of LAMP-based assays. In this report, we implemented a RT-LAMP assay for SARS-CoV-2 on a portable isothermal fluorimeter and a traditional thermocycler; nonspecific amplification was not observed using the thermocycler but did occur frequently with the isothermal fluorimeter. We explored 4 strategies to optimize the SARS-CoV-2 RT-LAMP assay for use with an isothermal fluorimeter and found that overlaying the reaction with mineral oil and including the enzyme Tte UvrD helicase in the reaction eliminated the problem. We anticipate these results and strategies will be relevant for use with a wide range of portable isothermal instruments.

High-risk human papillomavirus (HPV) DNA testing is widely acknowledged as the most sensitive cervical cancer screening method but has limited availability in resource-limited settings, where the burden of cervical cancer is highest. Recently, HPV DNA tests have been developed for use in resource-limited settings, but they remain too costly for widespread use and require instruments that are often limited to centralized laboratories. To help meet the global need for low-cost cervical cancer screening, we developed a prototype, sample-to-answer, point-of-care test for HPV16 and HPV18 DNA. Our test relies on isothermal DNA amplification and lateral flow detection, two technologies that reduce the need for complex instrumentation. We integrated all test components into a low-cost, manufacturable platform, and performance of the integrated test was evaluated with synthetic samples, provider-collected clinical samples in a high-resource setting in the United States, and self-collected clinical samples in a low-resource setting in Mozambique. We demonstrated a clinically relevant limit of detection of 1000 HPV16 or HPV18 DNA copies per test. The test requires six user steps, yields results in 45 min, and can be performed using a benchtop instrument and minicentrifuge by minimally trained personnel. The projected per-test cost is <$5, and the projected instrumentation cost is <$1000. These results show the feasibility of a sample-to-answer, point-of-care HPV DNA test. With the inclusion of other HPV types, this test has the potential to fill a critical gap for decentralized and globally accessible cervical cancer screening.

Background The global COVID-19 pandemic caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has highlighted the need for rapid, accurate, and accessible diagnostics to enable timely treatment and outbreak control. However, current diagnostic tests based on RT-qPCR are insufficient to meet the global testing demand because of their high cost and complexity and supply chain shortages. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a promising alternative to RT-qPCR because of its sensitivity, speed, and robustness to sample inhibitors. Here, we describe the development and optimisation of a sample-to-answer workflow, including a simple lysis and inactivation protocol that provides results in <1h, using inexpensive and readily available reagents. Further, we assess the sensitivity and specificity of the developed RT-LAMP assay against a RT-qPCR. Methods We collected samples from asymptomatic healthcare workers at The University of Texas MD Anderson Cancer Center and inpatients at Lyndon B Johnson Hospital in Houston, TX, USA. Nasopharyngeal swabs were collected by medical providers and were placed directly into 300 µL of an optimised lysis buffer. Samples were heat inactivated at 95°C for 5 mins before direct amplification in a RT-LAMP assay using previously published primer sets. Heating and real-time monitoring was performed using a Bio-Rad CFX96 thermocycler and an Axxin T8-ISO, a benchtop fluorimeter designed for point-of-care settings. We compared results from the RT-LAMP test with standardof-care RT-qPCR results on paired nasopharyngeal swabs collected into Universal Viral Transport Media. Findings The developed RT-LAMP assay demonstrated a limit of detection of 4-5 virions/µL. The test requires a swab, two tubes, prepared lysis buffer, a heat block, pipettes, RT-LAMP reagents, and the real-time fluorimeter. Samples were collected between April 14, 2020 and Aug 12, 2020, and results from 74 enrolled participants were analysed in the optimised workflow. Thirty nine participants tested positive for SARS-CoV-2 and 35 participants tested negative in the hospital-administered RT-qPCR test. All 74 nasopharyngeal swab eluates were tested with our assay on the Bio-Rad CFX96; 72 nasopharyngeal swab eluates were also tested on the Axxin T8-ISO. The developed assay showed sensitivity of 92•31% and 91•89% when tested on the CFX96 and T8, respectively, and specificity of 91•43% and 97•89%, respectively. Interpretation RT-LAMP could be used for SARS-CoV-2 testing and overcomes the challenges of adapting an assay to a point-of-care instrument. Further, the reduced instrumentation cost and complexity, along with the simple workflow, highlight the potential for implementation of RT-LAMP for SARS-CoV-2 testing in resource-limited settings.

Cervical cancer is a leading cause of cancer death for women in low-resource settings. The World Health Organization recommends that cervical cancer screening programs incorporate HPV DNA testing, but available...

Introduction: A relationship between hyperglycemia and outcomes in patients with COVID-19 has been proposed, however there is a paucity of literature on this. In this study, we examined the effect of admission glucose in diabetics and non-diabetics on outcomes in patients hospitalized with COVID-19. Our study uniquely examines this association in a largely African American cohort, a population disproportionately affected by COVID-19. Methods: In this retrospective cohort study, we analyzed all adults admitted with COVID-19 to a designated COVID hospital in Brooklyn, NY from March 1 to May 15, 2020. Diabetics were compared to non-diabetics, and were further stratified based on admission glucoses of 140 and 180 mg/dL. Diagnosis of diabetes was based on history and/or Hba1c &gt; 6.5%. Univariate, multiple and logistic regressions were used for analyses, examining outcomes of mortality, intubation, ICU admission, acute kidney injury (AKI), and length of stay based on admission glucose levels, while controlling for age, gender, lab values (serum creatinine and WBC), and comorbidities including hypertension, cardiovascular disease, and obesity. Outcomes are presented as an adjusted odds ratio (OR) with 95% confidence interval (95% CI). Results: 708 patients were analyzed; 54% diabetics, 83.5% non-Hispanic Blacks, 51% male with a mean age of 68, BMI of 29 kg/m2 and crude mortality rate of 40%. The length of hospital stay was greater in diabetics than non-diabetics, (13±26 days vs 9.5±18.5 days, p&lt;0.05). Diabetics with an admission glucose &gt; 140 mg/dL (vs&lt;140 g/dL) had a 2.4-fold increased odds of both intubation and ICU admission (95% CI: 1.2, 4.5; 1.3, 4.6). Diabetics with admission glucoses &gt; 180 mg/dL (vs &lt;180 g/dL) had a 1.8-fold increased mortality (95% CI: 1.2, 2.9). Non-diabetics with admission glucoses &gt;140 mg/dL (vs&lt;140 g/dL) had a two-fold increased mortality (95% CI: 1.2, 3.5), 3.5-fold increased odds of ICU admission (95% CI: 1.8,6.6) and a 2.3-fold increased odds of both intubation and AKI (95% CI: 1.3, 4.2; 1.3,4.2). Non-diabetics with a glucose &gt;180 mg/dL (vs &lt;180 g/dL) had a four-fold increased mortality (95% CI: 1.8, 8.8), 2.7-fold increased odds of intubation (95% CI: 1.3, 5.6) and 2.9-fold increased odds of ICU admission (95% CI: 1.3, 6.2). Conclusion: Our results show hyperglycemia portends worse outcomes in diabetics and non-diabetics with COVID-19. Elevated admitting glucoses &gt;180 mg/dL increased odds of mortality four-fold in non-diabetics and 1.8- fold in diabetics. In COVID-19, diabetic patients had a 37% greater length of hospital stay than non-diabetics. Whether hyperglycemia is a marker or a cause of more severe COVID-19 is unknown. These findings suggest that patients presenting with hyperglycemia require closer observation and more aggressive therapies. This raises the testable hypothesis that intensive glucose control may improve outcomes in patients with COVID-19.