Micro-flowcell conductometric sweat analysis for cystic fibrosis                diagnosis

This paper describes a device specifically designed to facilitate neonatal sweat testing. The components are sized appropriately for attachment to the limbs of newborns. Iontophoretic electrodes, with pilocarpine gel inserts, are latched into small holders attached by straps to the limb. The holder at the anodic site remains in place to receive and align the sensor cell, which uses a conical collecting surface to channel the sweat directly and anaerobically from the sweat ducts to the continuous flow-through conductivity cell within its body. A crib-side analysis unit incorporates an iontophoretic power supply and displays a continuous readout of sweat electrical conductivity. The average conductivity during a specific time interval and the initial sweating rate are automatically displayed. The method, which simplifies sweat tests, is currently being assessed in three neonatal clinical trials to test its ability to reduce test failures in the newborn due to insufficient sweat.

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Disposition of MDMA and Metabolites in Human Sweat Following Controlled MDMA Administration

Clinical Chemistry ◽

10.1373/clinchem.2008.117093 ◽

2009 ◽

Vol 55 (3) ◽

pp. 454-462 ◽

Cited By ~ 21

Author(s):

Allan J Barnes ◽

Bruno S De Martinis ◽

David A Gorelick ◽

Robert S Goodwin ◽

Erin A Kolbrich ◽

...

Keyword(s):

Solid Phase ◽

Random Order ◽

Research Unit ◽

Sweat Test ◽

Test Results ◽

Double Blind ◽

Scientific Database ◽

Sweat Testing ◽

Clinical Research Unit ◽

Sweat Tests

Abstract Background: Understanding the excretion of 3,4-methylenedioxymethamphetamine (MDMA) and metabolites in sweat is vital for interpretation of sweat tests in drug treatment, criminal justice, and workplace programs. Methods: Placebo, low (1.0 mg/kg), and high (1.6 mg/kg) doses of oral MDMA were given double-blind in random order to healthy volunteers (n = 15) with histories of MDMA use. Participants resided on the closed clinical research unit for up to 7 days after each dose. Volunteers wore PharmChek® sweat patches (n = 640) before, during, and after controlled dosing. Patches were analyzed by solid phase extraction and GC-MS for MDMA, methylenedioxyamphetamine (MDA), 4-hydroxy-3-methoxyamphetamine (HMA), and 4-hydroxy-3-methoxymethamphetamine (HMMA). Limits of quantification (LOQ) were 2.5 ng/patch for MDMA and 5 ng/patch for HMA, HMMA, and MDA. Results: MDMA was the primary analyte detected in 382 patches (59.7%), with concentrations up to 3007 ng/patch. MDA was detected in 188 patches (29.4%) at <172 ng/patch, whereas no HMMA or HMA was detected; 224 patches (35.0%) and 60 patches (9.4%) were positive for MDMA and MDA, respectively, at the 25-ng/patch threshold proposed by the Substance Abuse and Mental Health Services Administration. Conclusions: Sweat testing was shown to be an effective and reliable method for monitoring MDMA use in this controlled MDMA administration study. However, variability in sweat excretion suggests that results should be interpreted qualitatively rather than quantitatively. These data provide a scientific database for interpretation of MDMA sweat test results.

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Global Surgery indicators and pediatric hydrocephalus: a multicenter cross-country comparative study building the case for health systems strengthening

10.21203/rs.3.rs-307145/v1 ◽

2021 ◽

Author(s):

Kevin Paul Ferraris ◽

Eric Paolo Palabyab ◽

Sergei Kim ◽

Hideaki Matsumura ◽

Maria Eufemia Yap ◽

...

Keyword(s):

Health Systems ◽

Statistical Tests ◽

The Philippines ◽

Global Surgery ◽

Health Systems Strengthening ◽

Time Interval ◽

Late Time ◽

Csf Diversion ◽

Cross Country ◽

To Receive

Abstract Purpose: The aim of this study is to compare specific three-institution, cross-country data that are relevant to the Global Surgery indicators and the functioning of health systems. Methods: We retrospectively reviewed clinical and socioeconomic characteristics of pediatric patients who underwent CSF diversion surgery for hydrocephalus in three different centers: University of Tsukuba Hospital in Ibaraki, Japan (HIC), Jose R. Reyes Memorial Medical Center in Manila, Philippines (LMIC), and the Federal Neurosurgical Center in Novosibirsk, Russia (UMIC). The outcomes of interest were timing of CSF diversion surgery and mortality. Statistical tests included descriptive statistics, Cox proportional hazards model, and logistic regression. Nation-level data were also obtained to provide the relevant socioeconomic contexts in discussing the results. Results: In total, 159 children were included—13 from Japan, 99 from the Philippines, and 47 from the Russian Federation. The median time to surgery at the specific neurosurgical centers were 6 days in the Philippines and 1 day in both Japan and Russia. For the cohort from the Philippines, non-poor patients were more likely to receive CSF diversion surgery at an earlier time (HR=4.74, 95%CI 2.34–9.61, p<0.001). In the same center, those with infantile or post-hemorrhagic hydrocephalus (HR=3.72, 95%CI 1.70–8.15, p=0.001) were more likely to receive CSF diversion earlier compared to those with congenital hydrocephalus, and those with post-infectious (HR=0.39, 95%CI 0.22–0.70, p=0.002) or myelomeningocele-associated hydrocephalus (HR=0.46, 95%CI 0.22–0.95, p=0.037) were less likely to undergo surgery at an earlier time. For Russia, older patients were more likely to receive or require early CSF diversion (HR=1.07, 95%CI 1.01–1.14, p=0.035). EVD insertion was found to be associated with mortality (cOR 14.45, 95% CI 1.28–162.97, p = 0.031). Conclusion: In this study, Filipino children underwent late time-interval of CSF diversion surgery and had mortality differences compared to their Japanese and Russian counterparts. These disparities may reflect on the functioning of the respective country’s health systems.

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FerryBox data in the North Sea from 2002 to 2005

Earth System Science Data ◽

10.5194/essd-10-1729-2018 ◽

2018 ◽

Vol 10 (3) ◽

pp. 1729-1734 ◽

Cited By ~ 1

Author(s):

Wilhelm Petersen ◽

Susanne Reinke ◽

Gisbert Breitbach ◽

Michail Petschatnikov ◽

Henning Wehde ◽

...

Keyword(s):

Daily Basis ◽

Time Interval ◽

Arctic Seas ◽

Data Set ◽

The North ◽

The North Sea ◽

Flow Through ◽

Data Portal ◽

Data Gap ◽

Biogeochemical Parameters

Abstract. From 2002 to 2005 a FerryBox system was installed aboard two different ferries travelling between Cuxhaven (Germany) and Harwich (UK) on a daily basis. The FerryBox system is an automated flow-through monitoring system for measuring oceanographic and biogeochemical parameters installed on ships of opportunity. The variables were recorded in a time interval of 10–20 s, corresponding to a spatial resolution of about 100 m. The data set provides the parameters water temperature, salinity, dissolved oxygen and chlorophyll a fluorescence. There is a longer data gap between November 2002 and August 2003 in the time series due to a change of the vessel in October 2002. The data are available at https://doi.org/10.1594/PANGAEA.883824 (Petersen et al., 2017) and as part of the COSYNA (Coastal Observing System for Northern and Arctic Seas) data portal CODM at http://codm.hzg.de/codm (last access: September 2018) or https://doi.org/10.17616/R3K02T (Breitbach, 2018).

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Assessment of Sweat-Testing Practices for the Diagnosis of Cystic Fibrosis

Archives of Pathology & Laboratory Medicine ◽

10.5858/2001-125-1420-aostpf ◽

2001 ◽

Vol 125 (11) ◽

pp. 1420-1424 ◽

Cited By ~ 1

Author(s):

Vicky A. LeGrys

Keyword(s):

Clinical Laboratory ◽

Data Extraction ◽

National Committee ◽

Data Synthesis ◽

Study Selection ◽

Erroneous Result ◽

Sweat Testing ◽

Data Source ◽

Areas Of Concern ◽

Sweat Tests

Abstract Objective.—To describe the results of the College of American Pathologists survey questions assessing the current practice of sweat testing in North America and to identify areas in which improvement is needed. Data Source.—Results of the supplemental questions to the SW-B 2000 survey. Study Selection.—Supplemental questions were designed to assess variation in sweat collection, analysis, and interpretation. Data Extraction.—Extractions of the data were made based on the relevance of the data to the objectives of the review. Data Synthesis.—The majority of laboratories surveyed performed sweat testing according to the procedures described in the National Committee for Clinical Laboratory Standards' document. The study revealed that a number of laboratories have adopted poor practice standards and are potentially compromising patient care. Areas of concern include the number of laboratories performing few sweat tests per year, the persistence of unreliable methodology, misunderstanding of collection parameters, lack of patient education, and erroneous result reporting. Conclusions.—The study identified areas of concern toward which educational efforts can be directed. Such efforts include the development of a College of American Pathologists accreditation checklist for sweat testing and targeted responses in the sweat analysis participant summary report.

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Cardiac output using an electrically calibrated flow-through conductivity cell.

Journal of Applied Physiology ◽

10.1152/jappl.1974.37.6.972 ◽

1974 ◽

Vol 37 (6) ◽

pp. 972-977 ◽

Cited By ~ 13

Author(s):

L A Geddes ◽

E Peery ◽

R Steinberg

Keyword(s):

Cardiac Output ◽

Flow Through ◽

Conductivity Cell

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Modeling Water Balance of Dammed Lakes Using Computer Code Matlab-Simulink/ Modelowanie Bilansu Wodnego Piętrzonych Jezior Za Pomocą Programu Komputerowego Matlab-Simulink

Civil and Environmental Engineering Reports ◽

10.1515/ceer-2014-0021 ◽

2014 ◽

Vol 14 (3) ◽

pp. 5-14

Author(s):

Ryszard Błażejewski ◽

Sadżide Murat-Błażejewska ◽

Martyna Jędrkowiak

Keyword(s):

Water Balance ◽

Computer Code ◽

Water Levels ◽

Time Interval ◽

Lake Surface ◽

Time Intervals ◽

Matlab Simulink ◽

Surface Evaporation ◽

Flow Through ◽

Good Agreement

Abstract The paper presents a water balance of a flow-through, dammed lake, consisted of the following terms: surface inflow, underground inflow/outflow based on the Dupuit’s equation, precipitation on the lake surface, evaporation from water surface and outflow from the lake at which a damming weir is located. The balance equation was implemented Matlab-Simulink®. Applicability of the model was assessed on the example of the Sławianowskie Lake of surface area 276 ha and mean depth - 6.6 m, Water balances, performed for month time intervals in the hydrological year 2009, showed good agreement for the first three months only. It is concluded that the balancing time interval should be shorter (1 day) to minimize the errors. For calibration purposes, measurements of ground water levels in the vicinity of the lake are also recommended.

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FerryBox Data in the North Sea from 2002 to 2005

10.5194/essd-2018-12 ◽

2018 ◽

Author(s):

Wilhelm Petersen ◽

Susanne Reinke ◽

Gisbert Breitbach ◽

Michail Petschatnikov ◽

Henning Wehde ◽

...

Keyword(s):

Time Series ◽

North Sea ◽

Daily Basis ◽

Time Interval ◽

The North ◽

The North Sea ◽

Flow Through ◽

Data Portal ◽

Data Gap ◽

Biogeochemical Parameters

Abstract. From 2002 to 2005 a FerryBox system was installed aboard two different ferries travelling between Cuxhaven (GE) and Harwich (UK) on a daily basis. The FerryBox system is an automated flow-through monitoring system for measuring oceanographic and biogeochemical parameters installed on ships of opportunity. The variables were recorded in a time interval of 10–20 seconds corresponding to a spatial resolution of about 100 m. The dataset provides the parameters water temperature, salinity, dissolved oxygen and chlorophyll-a fluorescence. There is a longer data gap between November 2002 and August 2003 in the time series due to a change of the vessel in October 2002. The data are available at doi:10.1594/PANGAEA.883824 and as part of the COSYNA data portal CODM at http://codm.hzg.de/codm or doi:10.17616/R3K02T.

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3D Printed Skin-Wash Sampler for Sweat Sampling in Cystic Fibrosis Diagnosis Using Capillary Electrophoretic Ion Ratio Analysis

Separations ◽

10.3390/separations8120234 ◽

2021 ◽

Vol 8 (12) ◽

pp. 234

Author(s):

Miriam Malá ◽

Petra Itterheimová ◽

Lukáš Homola ◽

Jana Vinohradská ◽

Petr Kubáň

Keyword(s):

Cystic Fibrosis ◽

Skin Surface ◽

Single Step ◽

Ratio Analysis ◽

Sweating Rate ◽

Sampling Device ◽

Sweat Chloride ◽

3D Printed ◽

Flow Through ◽

Capillary Electrophoretic

Sweat chloride analysis is one of the important approaches in cystic fibrosis diagnosis. The commonly used Macroduct method to acquire sweat samples is semi-invasive, time consuming and expensive. Furthermore, this method often fails to collect a sufficient amount of sweat in newborns due to the insufficient sweating rate. In this work, we present a novel, simple, 3D-printed sampling device that is used to collect sweat specimens completely noninvasively in less than one minute. The device has a flow-through channel adjacent to the skin surface, through which 500 µL of deionized water is flushed and the spontaneously formed sweat on the skin in the channel area is washed into a plastic vial. The developed skin-wash procedure is a single step operation, is completely noninvasive and it always produces a sweat specimen. The ions from the skin-wash are subsequently analyzed by capillary electrophoresis with contactless conductivity detection and selected ion ratio (Cl−/K+) or ((Cl− + Na+)/K+) is used as a cut-off value to diagnose cystic fibrosis patients with sensitivity and specificity comparable to the conventional Macroduct method.

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Tuberculosis: evaluation of the time between identification of symptoms and beginning of treatment

Revista Brasileira de Enfermagem ◽

10.1590/0034-7167-2018-0902 ◽

2020 ◽

Vol 73 (6) ◽

Author(s):

Lívia Félix de Oliveira ◽

Laura Maria Vidal Nogueira ◽

Ivaneide Leal Ataíde Rodrigues ◽

Pedro Fredemir Palha

Keyword(s):

Respiratory Symptoms ◽

Data Distribution ◽

Sputum Smear ◽

Smear Microscopy ◽

Time Interval ◽

Molecular Test ◽

Sputum Smear Microscopy ◽

Significance Level ◽

To Receive ◽

The City

ABSTRACT Objective: To analyze the time elapsed between the identification of respiratory symptoms and the beginning of tuberculosis treatment, considering the sputum smear microscopy and the RMT. Method: Descriptive, retrospective epidemiological study, carried out in two Health Units, which were the only units that performed diagnosis by sputum smear microscopy and Rapid Molecular Test in the city. Data on respiratory symptoms with a positive result for tuberculosis were used. Analysis of data distribution and variance was performed, with a significance level of 5%. Results: The longest time interval found was “result/beginning of treatment”, for both tests, with a median of 3 days. It was found that the patient takes longer to receive the result when performing the Rapid Molecular Test. Conclusion: Patients who had the Rapid Molecular Test waited longer for results when compared to sputum smear microscopy, leading to a reflection on the need for further studies on the operation of health services.

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A study on the timing of HIV repeat test: A case study of Mary Immaculate VCT Center, Nairobi, Kenya

Clinical Social Work and Health Intervention ◽

10.22359/cswhi_12_2_11 ◽

2021 ◽

Vol 12 (2) ◽

pp. 57-62

Author(s):

V, Otieno Okech ◽

V. Wanjala Namulanda ◽

D. Kimuli

Keyword(s):

Short Interval ◽

Late Diagnosis ◽

Hiv Care ◽

Treatment Programs ◽

Time Interval ◽

Hiv Status ◽

Policy Makers ◽

Repeat Test ◽

To Receive

Population testing, especially those at risk, plays an important role in preventing and managing the HIV pandemic. It helps practitioners in identifying individuals who need to be counseled on behavior change as well as those who need to be enrolled in HIV care and treatment programs. Further still, policy makers also use outcomes of such tests in determining whether their strategies are bearing fruits or not. In this study, we sought to determine the time interval within which sexually active individuals seek HIV repeat tests in relation to their gender and marital statuses. We observed that majority of the respondents (39.8%, n=47) sought HIV repeat test within a period of 7-12 months, which we considered as short interval that leads to early diagnosis. We also observed a section of the respondents were also seeking HIV repeat test after a period that exceeded 13 months. We considered the latter as long interval that leads to late diagnosis of HIV. We further observed that, a majority of the respondents who were either married or had never been married before, sought HIV repeat tests within a short interval compared to those who were either divorced or widowed. We concluded that most widowed and divorced respondents were more likely to receive late diagnosis of HIV than those who were either married or had never been married before. Most studies have indicated that people who are unaware of their HIV status carry a higher risk of infecting others.

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