Plastic Pipette Research Articles

Melt-blown polypropylene nonwoven as an efficient and eco-economic sorbent for pipette tip micro-solid phase extraction for the determination of tyrosine kinase inhibitors

BackgroundThe detection of tyrosine kinase inhibitors (TKIs) in biological fluids is essential due to their critical role in cancer therapy and the variability in individual drug metabolism, which necessitates precise dosing. Traditional methods for analyzing TKIs in biological fluids, such as blood plasma, typically involve complex sample preparation techniques that can be resource-intensive, environmentally burdensome, and not sufficiently sensitive for low-concentration analytes. There is a pressing need for more efficient, economical, and environmentally friendly methods that can enhance sensitivity and throughput without compromising accuracy. ResultsThis study explores the use of melt-blown polypropylene nonwoven (MBPP), commonly found in face masks, as a novel sorbent for pipette-tip micro-solid phase extraction (PT-μSPE). MBPP demonstrated excellent hydrophobicity and significant mesoporous adsorption capacity. An extraction device was fashioned by inserting a segment of MBPP (15 mg) into a 200 μL disposable plastic pipette tip, which was then attached to a 2.5 mL disposable plastic syringe. The MBPP's fabric form removes the need for a frit, allowing the extraction process to be completed in just 3 min through simple plunger manipulation. The method achieved extraction recoveries ranging from 60.5 % to nearly 100 %. Subsequent method validation using liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed satisfactory linearity (coefficient of determination R2 > 0.993), accuracy (relative recoveries: 86.3%–114.8 %), and precision (relative standard deviation: 3.4%–11.3 %), with detection limits between 0.022 and 0.135 ng mL−1. SignificanceThe introduction of MBPP for PT-μSPE represents a significant advancement in the bioanalytical detection of TKIs, offering a highly efficient, cost-effective, and environmentally sustainable method. It compares favorably with existing techniques, offering advantages in terms of cost, environmental impact, and ease of use. This approach has the potential to be widely adopted for routine monitoring of TKIs in clinical settings.

Paper-in-Tip Bipolar Electrospray Mass Spectrometry for Real-Time Chemical Reaction Monitoring.

Capturing short-lived intermediates at the molecular level is key to understanding the mechanism and dynamics of chemical reactions. Here, we have developed a paper-in-tip bipolar electrolytic electrospray mass spectrometry platform, in which a piece of triangular conductive paper incorporated into a plastic pipette tip serves not only as an electrospray emitter but also as a bipolar electrode (BPE), thus triggering both electrospray and electrolysis simultaneously upon application of a high voltage. The bipolar electrolysis induces a pair of redox reactions on both sides of BPE, enabling both electro-oxidation and electro-reduction processes regardless of the positive or negative ion mode, thus facilitating access to complementary structural information for mechanism elucidation. Our method enables real-time monitoring of transient intermediates (such as N,N-dimethylaniline radical cation, dopamine o-quinone (DAQ) and sulfenic acid with half-lives ranging from microseconds to minutes) and transient processes (such as DAQ cyclization with a rate constant of 0.15 s-1). This platform also provides key insights into electrocatalytic reactions such as Fe (III)-catalyzed dopamine oxidation to quinone species at physiological pH for neuromelanin formation.

Paper‐in‐Tip Bipolar Electrospray Mass Spectrometry for Real‐Time Chemical Reaction Monitoring

AbstractCapturing short‐lived intermediates at the molecular level is key to understanding the mechanism and dynamics of chemical reactions. Here, we have developed a paper‐in‐tip bipolar electrolytic electrospray mass spectrometry platform, in which a piece of triangular conductive paper incorporated into a plastic pipette tip serves not only as an electrospray emitter but also as a bipolar electrode (BPE), thus triggering both electrospray and electrolysis simultaneously upon application of a high voltage. The bipolar electrolysis induces a pair of redox reactions on both sides of BPE, enabling both electro‐oxidation and electro‐reduction processes regardless of the positive or negative ion mode, thus facilitating access to complementary structural information for mechanism elucidation. Our method enables real‐time monitoring of transient intermediates (such as N,N‐dimethylaniline radical cation, dopamine o‐quinone (DAQ) and sulfenic acid with half‐lives ranging from microseconds to minutes) and transient processes (such as DAQ cyclization with a rate constant of 0.15 s−1). This platform also provides key insights into electrocatalytic reactions such as Fe (III)‐catalyzed dopamine oxidation to quinone species at physiological pH for neuromelanin formation.

Aptamer based hybrid monolithic pipette tips supported by melamine sponge for enrichment of proteins

BackgroundThe convenient preparation and application of functionalized organic-inorganic hybrid monolithic materials have obtained substantial interest in the pretreatment of complex samples by solid-phase extraction (SPE). Compared to the in-tube solid-phase microextraction in fused-silica capillaries, micro SPE in plastic pipette tips have fascinating merits for the easily operated enrichment of trace target analytes from biological samples. However, the poor compatibility of organic-inorganic hybrid monoliths with plastics leads to the rare appearance of commercial hybrid monolithic pipette tips (HMPTs). Therefore, how to synthesize the organic-inorganic hybrid monolithic materials with better extraction performance in plastic pipette tips becomes a challenge. ResultsWe develop a facile and cheap strategy to immobilize organic-inorganic hybrid monoliths in pipette tips. Melamine sponge was employed as the supporting skeleton to in situ assemble amine- and thiol-bifunctionalized hybrid monolithic material via “one pot” in a pipette tip, and gold nanoparticles (GNPs) and thiol-modified aptamer against human α-thrombin were sequentially attached to the hybrid monolith within the HMPTs. The average coverage density of the aptamer with GNPs as an intermediary reached as high as 818.5 pmol μL−1. The enriched thrombin concentration was determined by a sensitive enzymatic chromogenic assay with the limit of detection of 2 nM. The extraction recovery of thrombin at 10 nM in human serum was 86.1 % with a relative standard deviation of 6.1 %. This proposed protocol has been applied to the enrichment and determination of thrombin in real serum sample with strong anti-interference ability, low limit of detection and high recovery. SignificanceThe amine- and thiol-bifunctionalized HMPTs prepared with sponge as the skeleton frame provided a novel substrate material to decorate aptamers for efficient enrichment of proteins. This enlightens us that we can take advantage of the tunability of sponge assisted HMPTs to produce and tailor a variety of micro SPE pipette tips for broader applications on the analysis of trace targets in complex biological, clinic and environmental samples.

Langmuir–Blodgett films of magnetic nanowires

One-dimensional magnetic nanomaterials are scientifically interesting and of great importance due to their morphology-dependent properties. As a consequence of magnetic interactions between magnetic nanowires (MNWs) their bottom-up assembly remains a tough challenge. For the first time, using the Langmuir–Blodgett (LB) technique, we prepared two-dimensional (2D) large scale LB films of MNWs, which were synthesized by template directed electrodeposition method, on glass substrates. Using a plastic pipette, MNWs dispersed in chloroform were spread on the surface of the pure water subphase in a Teflon trough. After the stabilization of the monolayer, the Langmuir film was compressed and the surface pressure-area isotherm was recorded. By pulling up the substrate through the Langmuir film, mono- and bilayers of MNWs were deposited on the substrates at the target surface pressures of 10 mN/m and 15 mN/m. The surface pressure isotherm and field emission scanning electron microscope (FE-SEM) images showed that MNWs were successfully transformed onto the substrates. FESEM micrographs showed that the assembly of MNWs was different from that of metallic nanowires. Furthermore, the results showed that rotating the substrate by 90 degrees, after the deposition of the first layer, and then depositing the second layer on it does not lead to the creation of a hierarchical structure. These results open up new opportunities for the applications of magnetic nanomaterials in physical and chemical sensors, data-storage media and magnetic switching devices. Besides, this study affords fundamental insights into the formation of magnetic monolayers and multilayers.

Electrochemical detection of copper(II) in environmental samples using Penicillium sp. IITISM_ANK1 based biosensor

Detection of toxic metals at the lowest of their concentration in a variety of matrices has become a necessity due to the widespread and persistent nature of the contaminant. In this context, biosensors provide a viable alternative to the large sophisticated instrumentation. This study focuses on the development of a cost-effective fungal biomass-based biosensor that can be used for the detection of Cu(II). The fungal cells were pretreated with formaldehyde and studied with various spectroscopic studies. It was observed that the carbonyl groups along with amine groups played role in the sorption of copper ions which were stripped in an electrolytic solution to quantify the metal. Herein the dried fungal biomass was chemically activated and used to prepare a novel graphite paste electrode by repurposing a plastic pipette tip. The factors affecting the detection signal were optimized in further study. The electrochemical characterization revealed that the prepared bio-electrode was capable of detecting Cu in the range of 1 × 10−7 M to 2 × 10−5 M.

Clinical Microbiology in 2021: My Favorite Studies about Everything Except My Least Favorite Virus

Maybe 2021 wasn’t so bad after all! It was like 2020, but with COVID vaccines and better access to plastic pipette tips, and clearly, 2022 is getting off to a bad start. Even better, 2021 had some exciting papers in clinical microbiology, which is what is highlighted in this 2021 year in review. None of them are about COVID-19. Of course, there were some interesting discoveries about SARS-CoV-2 and COVID-19, but this review is completely COVID-19 free (almost).

Evaluation of a 3D-printed pipette tip for seeding housefly eggs

Egg manipulation is crucial in insect breeding and research. Housefly eggs are small, delicate and susceptible to dehydration. Hence, researchers require rapid and gentle ways to manipulate specific quantities, with consistent quality. Therefore, a 3D-printed pipette tip was designed and tested. Three series of pipette tips, differing in volume (A: 12.7 mm3; B: 15.2 mm3; and C: 17.7 mm3), were printed in triplicate and subjected to four experimental procedures. Eggs from a housefly colony were suspended in water, sucked up with the 3D-printed tip mounted on a Pasteur plastic pipette and released on a piece of coffee filter. Repeatability intra-run and reproducibility inter-day were evaluated by counting the eggs manipulated with the experimental tips. Time needed for egg sowing via a pipette tip was compared to time needed for counting 100 eggs delivered by a Paster pipette (control). Potential damage to eggs due to the pipette tip was estimated by quantifying fecundity (egg eclosion and larval survival). Coefficients of variation intra-run and inter-day were similar over replicates. Pipette set B had the best repeatability (coefficient of variation intra-run between 4.4 and 4.7%), and pipette set C the highest reproducibility (coefficient of variation inter-day of 2.6%). Egg damage due to the tip was negligible, however the tips did reduce larval survival (between 46.1±7.2% and 63.4±18.9%), compared to the control (between 66.0±2.4 and 75.5±9.3%). The pipette size and number of dispensed eggs correlated well (R2=0.90,P<0.001), but the relation was non-linear (y = 0.051034 x2+ 12.356 x – 0.03627). The time needed to sow a fixed number of eggs on the rearing substrate was reduced by 73% (pipette A) – 80% (pipette C) by using the pipette tip, compared to visual quantification.

Tricaine Methanesulfonate (MS222) Has Short-Term Effects on Young Adult Zebrafish (Danio rerio) Working Memory and Cognitive Flexibility, but Not on Aging Fish.

Exposure to anesthetic drugs is common in biomedical sciences being part of routine procedures in different translational species, however its impacts on memory and cognition are still debated, having different impacts depending on drug and age. The zebrafish (Danio rerio) is a translational species widely used in behavioral neuroscience, where tricaine methanesulfonate (MS222) is the most acceptable and used drug when conducting routine procedures. Based on this, we investigated the effects of MS222 (100 mg/l) in young adults and aging zebrafish 1, 2, 3, and 7 days after exposure. Animals’ were submitted to the anesthetic procedure until loss of body posture, slowing of opercular movements and lack of response to tail touch with a plastic pipette were achieved, then further left in the drug for 3 min. After that, animals (6 mpf vs. 24 mpf) were transferred to a recovery tank until fully recovered and transferred back to their housing system until further testing in the free movement pattern (FMP) Y-maze, which assesses zebrafish working memory and cognitive lexibility. Young animals had significant impairment in their working memory and cognitive flexibility 1 and 2 days after the exposure to MS222, being fully recovered by day 3 and with no effects 7 days post drug exposure. Increased repetitions were also observed for animals exposed to MS222 which could indicate increased stress-related response in animals up to 2 days after drug exposure. No drug effect was observed in aging animals besides their natural decreased alternations and working memory. Overall, behavioral experiments after routine procedures using MS222 should be performed with caution and need to be delayed, at least 3 days after exposure where working memory, cognitive flexibility, and repetitive behavior are back to normal.

Impact of Tyrosine Kinase Inhibitors Used in Chronic Myeloid Leukemia on Signaling and Epigenetics in Endothelial Cells

Background: Tyrosine kinase inhibitors (TKIs) have revolutionized treatment of chronic myeloid leukemia (CML) resulting in long term survival with chronic therapy. Vascular toxicities have emerged as complications of the second generation CML TKIs; dasatinib, ponatinib and nilotinib. Dasatinib is associated with increased risk of pulmonary hypertension, ponatinib with arterial ischemic events and nilotinib with peripheral arterial occlusive events and cardiovascular ischemia by unknown mechanisms. The first generation CML TKI imatinib is not associated with vascular toxicity.Hypothesis: We hypothesize that the CML TKIs- ponatinib, dasatinib and nilotinib, but not imatinib, cause vascular toxicity by affecting endothelial cell (EC) function in association with alterations in phospho-signaling and histone modifications.Methods To test this hypothesis, we studied the effect of CML TKIs imatinib, nilotinib, dasatinib and ponatinib on EC function using three in-vitro assays measuring EC survival, EC-leucocyte adhesion (a measure of vascular inflammation) and scratch wound closure (a measure of wound healing capacity). Cultured human umbilical vein ECs (HUVECs) were treated with vehicle, imatinib (4uM), dasatinib (200nM), nilotinib (3 uM) or ponatinib (100nM). Cell viability was measured at 18 hours using a Cell TiterGlo Luminescent Cell Viability assay (Promega). For the leucocyte adhesion assay, fluorescent labeled leucocytes (U937) were incubated with the ECs and adherent fluorescent cells were quantified. For the wound healing assay, a scratch “wound” was made with a plastic P1000 pipette tip and cells that migrated into the wound area were counted at 18 hours. To assess signaling, two novel, global, unbiased, high throughput proteomic assays developed at the Broad Institute were used. The P100 assay is a mass spectrometry-based targeted proteomics assay that quantifies 100 representative phosphopeptides. The global chromatin profiling (GCP) assay uses mass spectrometry to simultaneously quantify over 70 bulk histone modifications including phosphorylation, ubiquitination, methylation and acetylation. HUVECs were treated in triplicate with each drug for 3 hours for the P100 assay and for24 hours for the GCP assay. For each assay, the peptides were mixed with isotopically labeled internal standards and mass spectrometry was performed to quantify each phospho-peptide or modified histone peptide relative to the universal standard.Results: The CML TKIs that are associated with vascular toxicity (nilotinib, ponatinib and dasatinib) negatively impacted all the EC functions measured. Specifically, nilotinib, ponatinib and dasatinib significantly decreased endothelial cell viability and endothelial cell migration in response to a scratch wound and increased leucocyte adhesion to ECs. Imatinib did not have a negative effect on ECs in any of those assays. Using the mass spectrometry based P100 and GCP assays, we found that nilotinib affects histone epigenetics and protein phosphorylation in HUVECs. In particular, nilotinib treatment modulates ABL1, MAP4, BRD4 and JUND phosphorylation and also increases histone H3K9 trimethylation with H3S10 phosphorylation in HUVECS. We also compared the nilotinib profiles obtained in HUVECs to that of primary human aortic smooth muscle cells (HAoSMC) and several cancer cell lines including MCF7 (breast), A549 (lung), A375 (skin) and PC3 (prostate) (Figures 1a and 1b). While some changes are unique to ECs, others are similar to the effects in cancer cells and smooth muscle cells. GCP assay and P100 assays comparing the effects of all the CML TKIs in endothelial cells are in process.Conclusions: CML TKIs associated with vascular toxicity affect human EC function in vitro resulting in impaired endothelial survival and wound healing and increase inflammation. These changes are associated with alterations in signaling and epigenetic pathways in ECs in response to treatment with nilotinib. Increased vascular inflammation and impaired vascular healing are associated with cardiovascular thrombosis and ischemia. Further studies comparing the effects of all CML TKIs on ECs will be used to elucidate molecular mechanisms of vascular toxicity and help devise strategies to overcome these toxicities while maintaining anti-cancer efficacy. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

A portable instrument for on-site detection of heavy metal ions in water.

Based on differential pulse voltammetry technology, we developed a portable and affordable instrument for on-site detection of trace heavy metal pollutants in liquid through a disposable plastic pipette. It mainly consists of a six-electrode electrochemical sensor which is integrated in the instrument. The pipette chip is equipped with a pump valve, and thus, it can avoid contamination. We have analyzed the sensitivity and specificity of the electrochemical sensor for heavy metal detection. Experimental results demonstrated that the limit of detection for Pb, Hg, Cu, and Zn was 2.2ng/mL, 2.5ng/mL, 15.5ng/mL, and 10ng/mL, respectively. The limit of quantification for them was 10ng/mL, 25ng/mL, 25ng/mL, and 14ng/mL, respectively. The correlation coefficient between peak current and the target heavy metal concentration was above 0.96. Finally, we have tested the analytical performance of the self-build instrument by measuring heavy metal ions in industrial wastewater and rainwater, respectively. Such an instrument is user-friendly for all users even for the common people, and we can envision its wide application in future heavy metal pollutant detection in groundwater, tap water, and supernatant of soil solution.

Capillary Effect Enhancement in a Plastic Capillary Tube by Nanostructured Surface.

We investigated the enhancement of the capillary effect in a plastic capillary tube using only a nanostructured surface. Since plastic is a hydrophobic material, the capillary effect does not emerge without an additional coating or plasma treatment process. Therefore, capillary effect enhancement by the nanostructure fabrication method is expected to reduce the cost and minimise the contamination produced in the human body. By combining a hydrophilic nylon resin and a nanostructure at the tip of the plastic pipette, we could confirm that the capillary effect was produced solely by the tube fabrication process. The produced capillary effect increased linearly with increasing nanostructure height when a standard solution with a surface tension of 70 mN·m−1 was used. Thus, we can conclude that including the plastic part with nanostructure can be useful for biomedical applications. In addition, we suggest that the proposed method is highly effective in controlling the wetting properties of plastic surfaces, compared to the typical coating or plasma treatment processes.

Acoustic Investigation of Textile Fabrics

Why is it possible to distinguish between different textile fabrics by just touching them and moving your hand over them and listening to the sound? Particularly for high-quality woven fabrics, e.g. used for tailor-made suits, it is quite common that the dressmaker listens to the sound as their hand rubs the fabric. Can this approach be translated into a technical measurement? What could a sound analysis tell us about the fabric properties? As a first simple approach, we used a record player to rotate different cotton fabrics, and tested fine tips from diverse materials, such as plastic pipettes, pens, glass tips, etc. Our results show clear differences between the textile fabrics, which can be attributed to different yarn, knitted or woven structures. While the rotational mode of investigation impedes fully automated fast Fourier transform (FFT) evaluations, our first results suggest de¬veloping this promising method further.

Study on the Fauna of Aquatic Insects in Northwestern Iran

Background:Aquatic insects include groups of arthropods which at least one step of their life happens in water. Some of these insects play an important role in the transmission of various diseases to human and animals. Because there is a little information about the fauna of aquatic insects in Iran, this study was aimed to collect and identify aquatic insects in northwestern Iran.Methods:A descriptive cross sectional study was performed in July 2017 in Rivers of three villages of Osku County of East Azerbaijan Province, northwestern Iran. The specimens were collected using different methods including D frame net-collector, standard mosquito dipper, Sweep Netting and plastic pipette. The collected specimens were identified based on the systematic keys of aquatic insects.Results:Totally 285 samples were collected. Four orders including Diptera, Hemiptera, Ephemeroptera and Coleoptera were identified. Collected samples belonged to seven families of Tipulidae, Chironomidae, Corixidae, Culicidae, Hydrophilidae, Baetidae and Dytiscidae. The most predominant family was Culicidae belonging to order Diptera. Culiseta longiareolata was the most frequent species collected in the study area.Conclusion:Aquatic insects usually play an important role in the food chain of animals and some species of them act as predators and play an important role in the biological control of vectors. Therefore, more studies are required to carry out in the field of aquatic insects.

IMPLEMENTASI ALAT PERAGA EDUKASI PIPLAS (PIPET PLASTIK) UNTUK MENINGKATKAN PEMAHAMAN IPA PADA SISWA DI SMP NEGERI 1 GANGGA

The study aims to increase the understanding of gene concepts and inheritance by providing a more concrete representation of the genes. The design of this research uses the quantitative approach of experimentation. Subjects and objects of study are students of grade IX-5 SMP Negeri 1 Gangga, amounting to 29 not one person until a total of 28 people. This Piplas educational tool is very simple because it only makes use of plastic pipettes used by ice-drinking students. Usually plastic pipettes are used for crafting, but are used to provide a concrete representation of the genes. The results showed that most students are easier to understand the concept of genes, capable of making crosses easily so as to improve learning outcomes. Tests were given before learning obtained an average value of 30.79 and after learning obtained an average value of 69.4 an increase of 125.4%.

INHERITED PROTEIN C AND PROTEIN S DEFICIENCY IN RENAL TRANSPLANT CANDIDATES OF SINDH PROVINCE, PAKISTAN

Background: Thrombophilia is a common risk factor for venous thromboembolism. The objective of this study was to determine prevalence of inherited protein C and protein S deficiency in renal transplant candidates of Sindh Province, Pakistan. Material & Methods: This cross-sectional study was conducted in Department of Pathology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan from 16-10-2010 to 15-4-2011. 300 renal transplant candidates were selected. Candidates with acquired thrombotic disorders, women taking oral contraceptives and patients taking anti-coagulants during previous one week were excluded. Venous blood samples were collected before starting dialysis procedure or at least two days after last dialysis session. Platelet-poor plasma (PPP) was parted using plastic pipettes and protein C and protein S were processed on coagulation analyzer. Sex, age groups (<40 and ≥ 40years), presence of protein C deficiency and presence of protein S deficiency were nominal variables and analyzed by count and percentage along with population parameters. Results: 300 renal transplant candidates included 199 (66.33%) men and 101 (33.67%) women and 238 (79.33%) in age group <40 years and 62 (20.67%) cases in age group ≥40 years. Prevalence of protein C deficiency was 6.66% (20/300) and of protein S deficiency was 4% (12/300). Prevalence of PC deficiency was higher in men 5.33% than women 1.33%. Also prevalence of PS deficiency was higher in men 3.0% than women 1.0%. Prevalence of PC deficiency was higher in age group <40 years 5.67% than ≥40 years 1.0%. Also prevalence of PS deficiency was higher in age group <40 years 3.33% than ≥40 years 0.66%. Conclusion: More prolonged and follow-up studies are needed to define the true significance of deficiency of protein C and S (coagulation inhibitors) in post-transplant settings.

Laparoscopy-assisted Neocervicovaginal Reconstruction in a Rare Case of Müllerian Anomaly: Cervicovaginal Aplasia with Unicornuate Uterus

To demonstrate a technique of laparoscopy-assisted neocervicovaginal reconstruction in a case of cervicovaginal aplasia. Step-by-step demonstration of the surgery in an instructional video. Cervicovaginal aplasia is a rare congenital anomaly that occurs in 1 in 80 000 to 100 000 live births [1]. Occasionally, there can be other associated anomalies. Epigenetic modifications of homeobox and Wnt genes (wingless-type mouse mammary tumor virus integration site family) are hypothesized to cause defects in the development of the müllerian reproductive tract by interfering with cell migration during organogenesis [2]. Our patient was a 15-year-old girl who had a unicornuate uterus along with cervicovaginal aplasia (American Society for Reproductive Medicine class Ia, Ib, and IIc and European Society of Human Reproduction and Embryology class U4a, C4, and V4). The most common approach to treat this particular anomaly is hysterectomy, but there are many reports of neocervicovaginal reconstruction with good results [3]. Laparoscopic assessment showed a right unicornuate uterus with hematometra, right hematosalpinx, and a left noncavitary rudimentary horn with endometriosis. A vertical incision was made over the most prominent bulging part of the uterine fundus, and the hematometra was drained. Laparoscopic inspection of the uterine cavity showed an irregular cavity with thickened endometrium. The cervical canal could not be identified. The inspection of the external genitalia revealed complete vaginal aplasia. An inverted T incision was made over the vestibule and neovagina created by blunt digital dissection. The bladder was laparoscopically mobilized down. A Maryland dissector was inserted into the uterine cavity through the incision in the fundus and directed toward the neovagina. The myometrium was then punctured while simultaneously visualizing the neovagina to create a neocervix. A 16-F Foley's catheter was then pulled into the uterine cavity with the Maryland dissector from the vaginal end. The neocervix was enlarged around the catheter and then sutured to the vestibular epithelium with 6 interrupted 1-0 polyglactin sutures. The Foley's catheter was anchored to the myometrium laparoscopically, and the uterine incision was closed with interrupted 1-0 polyglactin sutures. The right hematosalpinx was then excised. The intravaginal plastic mold was removed after 4 days. The patient was advised to use the bulb of a plastic pipette to help maintain vaginal patency. She resumed her menses 3 weeks after the surgery. Follow-up at 8 months revealed a normal-sized uterus on transabdominal ultrasound and a vaginal length of 5.5 cm on speculum examination. She currently reports regular cyclic menstruation with mild dysmenorrhea and has not yet begun sexual activity. Cervicovaginal aplasia can be successfully treated by laparoscopy-assisted neocervicovaginal reconstruction as demonstrated in the video.

Direct Analysis of Aqueous Solutions and Untreated Biological Samples Using Nanoelectrospray Ionization Mass Spectrometry with Pipette Tip in Series with High-Ohmic Resistor as Ion Source.

Commercially available disposable plastic pipette tip with the inner diameter of ca. 120μm in series with a high-ohmic resistor (10GΩ) was adapted as a low-cost alternative ion source for high-throughput nanoelectrospray mass spectrometry (nESI-MS) analysis of a variety of samples, especially aqueous solutions, without sample pretreatment. The use of high-ohmic resistor enabled the formation of stable electrospray of aqueous solutions at ambient conditions. In addition, corona discharge was avoided even with a high voltage applied. Quantitative analysis of vitamin B in water was successfully conducted by tip-ESI. The results exhibited a good linearity (R ˃0.9983), a low detection limit (0.25ng/mL), and a wide dynamic response range (0.25-1000ng/mL). Our study revealed that tip-ESI not only performed equally well to capillary nESI in terms of flow rate (˂100nL/min), signal sensitivity, and sample consumption, but also offered a number of additional advantages, including better signal duration, tolerance to high analyte concentration (> 100μg/mL) and high ionizing voltage (up to 6kV), and obviation of tip clogging and corona discharge. High compatibility of tip-ESI with various kinds of samples (aqueous, viscous, solid, or bulk biological samples) makes it a promising tool for direct MS analysis.

Diversidad de mosquitos (Diptera: Culicidae) de Jarabacoa, República Dominicana

En República Dominicana tienen especial interés, dada su gran relevancia médica, las enfermedades transmitidas por mosquitos. La presente investigación profundiza sobre la diversidad de los culícidos existentes en el municipio de Jarabacoa, a fin de actualizar la información sobre estos dípteros y sus principales sitios de cría, naturales y artificiales. Para tal cometido, se procedió a la búsqueda activa de formas preimaginales mediante la técnica del dipper; se utilizaron pipetas plásticas para muestrear en reservorios de pequeño tamaño. La identificación se llevó a cabo mediante la utilización de lupa binocular y microscopio, con la ayuda de claves taxonómicas específicas. Se capturaron 16 especies pertenecientes a los géneros Aedes Meigen, 1818, Anopheles Meigen, 1818, Culex Linnaeus, 1758, Toxorhynchites Theobald, 1901, Uranotaenia Lynch Arribálzaga, 1891 y Wyeomyia Theobald, 1901, sobre las que se analizaron diversas cuestiones acerca de su bioecología y su papel en la transmisión de agentes patógenos de importancia médica. Se reporta Culex biscaynensis Zavortink & O’Meara, 1999 por primera vez en el Caribe insular, con lo que el número de especies de mosquitos citadas en el país se eleva a 50.

Accuracy, Ease of Use, Safety, and Acceptability of a 23-μL Conical Cup Blood Transfer Device for Use with Rapid Diagnostic Tests.

.Devices to safely transfer fixed amounts of finger prick blood to rapid diagnostic tests (RDTs) pose a significant challenge, especially in non-laboratory settings. Following the success of an “inverted cup device” for transfer of 5 μL blood, a prototype with a conical cup shape was developed for transfer of 20 μL blood, the amount needed for human immunodeficiency virus or human African trypanosomiasis (HAT) RDTs. This study determined the volume of blood transferred by this new blood transfer device (BTD) and compared its ease of use, safety, and acceptability with that of a plastic pipette when used by health workers (HWs) for HAT RDTs in northwestern Uganda. After a half-day training, 48 HWs had used the two BTDs with at least 10 patients. The conical cup BTD effectively transferred a mean of 22.76 μL of blood (standard deviation 3.31 μL). A significantly higher proportion of HWs were able to collect the full amount of blood using the conical cup BTD, as compared with the pipette (92.4% versus 74.2%, P < 0.001). In HW questionnaires, the conical cup BTD scored higher than the pipette in various aspects of ease of use and safety. In addition, HWs preferred the conical cup BTD (79%), indicating that it was easy to handle, made work faster, and increased their confidence in front of the patient. These findings suggest that the design of the conical cup BTD may be adapted for RDTs requiring 20 μL of blood to facilitate safe and accurate blood transfer.