SpyDirect: A Novel Biofunctionalization Method for High Stability and Longevity of Electronic Biosensors

Electronic immunosensors are indispensable tools for diagnostics, particularly in scenarios demanding immediate results. Conventionally, these sensors rely on the chemical immobilization of antibodies onto electrodes. However, globular proteins tend to adsorb and unfold on these surfaces. Therefore, self-assembled monolayers (SAMs) of thiolated alkyl molecules are commonly used for indirect gold-antibody coupling. Here, a limitation associated with SAMs is revealed, wherein they curtail the longevity of protein sensors, particularly when integrated into the state-of-the-art transducer of organic bioelectronics-the organic electrochemical transistor. The SpyDirect method is introduced, generating an ultrahigh-density array of oriented nanobody receptors stably linked to the gold electrode without any SAMs. It is accomplished by directly coupling cysteine-terminated and orientation-optimized spyTag peptides, onto which nanobody-spyCatcher fusion proteins are autocatalytically attached, yielding a dense and uniform biorecognition layer. The structure-guided design optimizes the conformation and packing of flexibly tethered nanobodies. This biolayer enhances shelf-life and reduces background noise in various complex media. SpyDirect functionalization is faster and easier than SAM-based methods and does not necessitate organic solvents, rendering the sensors eco-friendly, accessible, and amenable to scalability. SpyDirect represents a broadly applicable biofunctionalization method for enhancing the cost-effectiveness, sustainability, and longevity of electronic biosensors, all without compromising sensitivity.

Wireless, battery-free, multifunctional integrated bioelectronics for respiratory pathogens monitoring and severity evaluation

The rapid diagnosis of respiratory virus infection through breath and blow remains challenging. Here we develop a wireless, battery-free, multifunctional pathogenic infection diagnosis system (PIDS) for diagnosing SARS-CoV-2 infection and symptom severity by blow and breath within 110 s and 350 s, respectively. The accuracies reach to 100% and 92% for evaluating the infection and symptom severity of 42 participants, respectively. PIDS realizes simultaneous gaseous sample collection, biomarker identification, abnormal physical signs recording and machine learning analysis. We transform PIDS into other miniaturized wearable or portable electronic platforms that may widen the diagnostic modes at home, outdoors and public places. Collectively, we demonstrate a general-purpose technology for rapidly diagnosing respiratory pathogenic infection by breath and blow, alleviating the technical bottleneck of saliva and nasopharyngeal secretions. PIDS may serve as a complementary diagnostic tool for other point-of-care techniques and guide the symptomatic treatment of viral infections.

Highly integrated watch for noninvasive continual glucose monitoring

This article reports a highly integrated watch for noninvasive continual blood glucose monitoring. The watch employs a Nafion-coated flexible electrochemical sensor patch fixed on the watchband to obtain interstitial fluid (ISF) transdermally at the wrist. This reverse iontophoresis-based extraction method eliminates the pain and inconvenience that traditional fingerstick blood tests pose in diabetic patients' lives, making continual blood glucose monitoring practical and easy. All electronic modules, including a rechargeable power source and other modules for signal processing and wireless transmission, are integrated onto a watch face-sized printed circuit board (PCB), enabling comfortable wearing of this continual glucose monitor. Real-time blood glucose levels are displayed on the LED screen of the watch and can also be checked with the smartphone user interface. With 23 volunteers, the watch demonstrated 84.34% clinical accuracy in the Clarke error grid analysis (zones A + B). In the near future, commercial products could be developed based on this lab-made prototype to provide the public with noninvasive continual glucose monitoring.

Research Note: Orange corn altered the cecal microbiome in laying hens

Carotenoids, which are pigments known to have many health benefits, such as their antioxidant properties, are being researched for their potential as a feed additive for production animals. These pigments are found in varying quantities in different breeds of corn, and their impact on the chicken microbiome requires further investigation. This 35 d laying hen (Novagen White) feeding trial involved varying the levels and composition of carotenoids by changing the corn source: white (0.9 µg total carotinoids/g total diet), yellow (5.7 µg/g), and orange (24.9 µg/g). For each of the three corn diet treatments, 6 replicate cages were randomly assigned. The cecal microbial community composition of the hens was then studied by 16S rRNA gene amplicon sequencing. The composition of the cecal bacterial community, as determined by Bray-Curtis dissimilarity, was different (P < 0.05) in chickens fed the orange corn diet, compared to chickens on the white corn diet, but there was no statistical difference between animals fed yellow corn compared to the white or orange corn groups. There was no change in the alpha diversity between any of the groups. Within Lactobacillus, which is one of the most abundant genera, 2 amplicon sequence variants (ASVs) were decreased and one ASV was increased in the orange corn group compared to both the white and yellow corn groups. While previous studies showed that orange corn did not alter the community composition in broilers, it appears that orange corn based feed may alter the community composition of laying hens.

Neonatal encephalopathy: Etiologies other than hypoxic-ischemic encephalopathy

Neonatal encephalopathy (NE) describes the clinical syndrome of a newborn with abnormal brain function that may result from a variety of etiologies. HIE should be distinguished from neonatal encephalopathy due to other causes using data gathered from the history, physical and neurological exam, and further investigations. Identifying the underlying cause of encephalopathy has important treatment implications. This review outlines conditions that cause NE and may be mistaken for HIE, along with their distinguishing clinical features, pathophysiology, investigations, and treatments. NE due to brain malformations, vascular causes, neuromuscular causes, genetic conditions, neurogenetic disorders and inborn errors of metabolism, central nervous system (CNS) and systemic infections, and toxic/metabolic disturbances are discussed.

Single Living Cell Analysis Nanoplatform for High-Throughput Interrogation of Gene Mutation and Cellular Behavior

The genetic heterogeneities in cancer cells pose challenges to achieving precise drug treatment in a widely applicable manner. Most single-cell gene analysis methods rely on cell lysis for gene extraction and identification, showing limited capacity to provide the correlation of genetic properties and real-time cellular behaviors. Here, we report a single living cell analysis nanoplatform that enables interrogating gene properties and drug resistance in millions of single cells. We designed a Domino-probe to identify intracellular target RNAs while releasing 10-fold amplified fluorescence signals. An on-chip addressable microwell-nanopore array was developed for enhanced electro-delivery of the Domino-probe and in situ observation of cell behaviors. The proof-of-concept of the system was validated in primary lung cancer cell samples, revealing the positive-correlation of the ratio of EGFR mutant cells with their drug susceptibilities. This platform provides a high-throughput yet precise tool for exploring the relationship between intracellular genes and cell behaviors at the single-cell level.

A novel methodology to study antimicrobial properties of high-touch surfaces used for indoor hygiene applications-A study on Cu metal

Metal-based high-touch surfaces used for indoor applications such as doorknobs, light switches, handles and desks need to remain their antimicrobial properties even when tarnished or degraded. A novel laboratory methodology of relevance for indoor atmospheric conditions and fingerprint contact has therefore been elaborated for combined studies of both tarnishing/corrosion and antimicrobial properties of such high-touch surfaces. Cu metal was used as a benchmark material. The protocol includes pre-tarnishing/corrosion of the high touch surface for different time periods in a climatic chamber at repeated dry/wet conditions and artificial sweat deposition followed by the introduction of bacteria onto the surfaces via artificial sweat droplets. This methodology provides a more realistic and reproducible approach compared with other reported procedures to determine the antimicrobial efficiency of high-touch surfaces. It provides further a possibility to link the antimicrobial characteristics to physical and chemical properties such as surface composition, chemical reactivity, tarnishing/corrosion, surface roughness and surface wettability. The results elucidate that bacteria interactions as well as differences in extent of tarnishing can alter the physical properties (e.g. surface wettability, surface roughness) as well as the extent of metal release. The results clearly elucidate the importance to consider changes in chemical and physical properties of indoor hygiene surfaces when assessing their antimicrobial properties.

Can pain flares in knee osteoarthritis be predicted?

Objectives: This study examined whether risk factors for knee osteoarthritis (KOA) pain such as age, gender, body mass index (BMI), baseline pain, and other putative risk factors for knee osteoarthritis pain flares (KOAF) (e.g. knee buckling, injury, mood/stress/social support scores, and footwear) could predict KOAF.Method: People with KOA and previous history of KOAF were selected from a 3 month web-based longitudinal study. KOAF was defined as an increase of ≥ 2 points on a numeric rating scale (compared with background pain) which resolved within 20 days. Predictors assessed at baseline were gender, age, duration of KOA, BMI, pain, knee injury (7 days before), knee buckling (2 days before), Lubben Social Support, Knee Injury and Osteoarthritis Outcome Score, Intermittent and Constant Osteoarthritis Pain score (ICOAP), Positive/Negative Affect Score, and footwear stability/heel height. Outcome was occurrence of any KOAF during the ensuing 30 days. The combined ability of the above variables to predict occurrence of any KOAF was evaluated by multiple logistic regression with a 10-fold cross-validation method to build and internally validate the model. Variables that assessed similar domains were eliminated using receiver operating characteristics curve assessment for best fit.Results: Complete data were available for 313 people (66.6% female, mean ± sd age 62.3 ± 8.2 years, BMI 29.7 ± 6.5 kg/m²). Increasing age, years of osteoarthritis, BMI, background/worst levels of pain, knee injury, knee buckling, ICOAP, and footwear category/heel height significantly predicted the occurrence of KOAF during the following 30 days, with an area under the curve of 0.73 (95% confidence interval 0.67-0.80).Conclusion: A combination of risk factors assessed at baseline, including exposures with potential to vary, successfully predicts the KOAF in the ensuing 30 days.

Relationship between postpartum mood disorder and birth experience: a prospective observational study

BACKGROUND

This study aims to investigate the relationship between the birth experience and the risk of developing postpartum depression or post-traumatic stress disorder.

METHODS

In this prospective, longitudinal, observational study, women were assessed at different time points for depression and post-traumatic stress disorder. The risk of depression or post-traumatic stress disorder based on patient characteristics and specific birth events was assessed within three months postpartum.

RESULTS

We enrolled 600 women; 426 were eligible for postpartum assessment. At six weeks and three months postpartum, 15.9% and 12.7% screened positive for depression respectively. Positive post-traumatic stress disorder screenings at six weeks and three months postpartum were 6.2% and 5.1% respectively. Twenty-seven women (8.3%) with a negative screening at six weeks converted to a positive depression or post-traumatic stress disorder screening at three months. A pre-existing history of anxiety or depression was associated with an increased risk of developing depression (aOR 2.12, 95% CI 1.30 to 3.47) and post-traumatic stress (aOR 3.15, 95% CI 1.42 to 7.02) within three months postpartum. The risk of developing post-traumatic stress disorder within three months postpartum was also increased among patients experiencing their first delivery (aOR 2.55, 95% CI 1.10 to 5.88) or operative management of postpartum hemorrhage (aOR 4.44, 95% CI 1.16 to 17.02).

CONCLUSION

Depression and post-traumatic stress symptoms either persisted or had new onset at three months postpartum. Mental health screening and postpartum follow-up after six weeks should be considered in high-risk patients who have a history of psychopathology, nulliparity, or undergo operative management of postpartum hemorrhage.

Genome-wide association study reveals candidate genes associated with body measurement traits in Chinese Wagyu beef cattle

We performed a genome-wide association study to identify candidate genes for body measurement traits in 463 Wagyu beef cattle typed with the Illumina Bovine HD 770K SNP array. At the genome-wide level, we detected 18, five and one SNPs associated with hip height, body height and body length respectively. In total, these SNPs are within or near 11 genes, six of which (PENK, XKR4, IMPAD1, PLAG1, CCND2 and SNTG1) have been reported previously and five of which (CSMD3, LAP3, SYN3, FAM19A5 and TIMP3) are novel candidate genes that we found to be associated with body measurement traits. Further exploration of these candidate genes will facilitate genetic improvement in Chinese Wagyu beef cattle.

Unexpected Stretching of Entangled Ring Macromolecules

In the melt state at equilibrium, entangled nonconcatenated ring macromolecules adapt more compact conformations compared to their linear analogs and do not form an entanglement network. We show here that, when subjected to uniaxial stretching, they exhibit a unique response, which sets them apart from any other polymer. Remarkably, whereas both linear and ring polymers strain-harden, the viscosity of the rings increases dramatically (the melt thickens) at very low stretch rates due to the unraveling of their conformations along the stretching direction. At high rates, stretching leads to viscosity thinning similar to that of entangled linear polymers, albeit with subtle differences.

Cerebral Perfusion Is Perturbed by Preterm Birth and Brain Injury

BACKGROUND AND PURPOSE

Early disturbances in systemic and cerebral hemodynamics are thought to mediate prematurity-related brain injury. However, the extent to which CBF is perturbed by preterm birth is unknown. Our aim was to compare global and regional CBF in preterm infants with and without brain injury on conventional MR imaging using arterial spin-labeling during the third trimester of ex utero life and to examine the relationship between clinical risk factors and CBF.

MATERIALS AND METHODS

We prospectively enrolled preterm infants younger than 32 weeks' gestational age and <1500 g and performed arterial spin-labeling MR imaging studies. Global and regional CBF in the cerebral cortex, thalami, pons, and cerebellum was quantified. Preterm infants were stratified into those with and without structural brain injury. We further categorized preterm infants by brain injury severity: moderate-severe and mild.

RESULTS

We studied 78 preterm infants: 31 without brain injury and 47 with brain injury (29 with mild and 18 with moderate-severe injury). Global CBF showed a borderline significant increase with increasing gestational age at birth (P = .05) and trended lower in preterm infants with brain injury (P = .07). Similarly, regional CBF was significantly lower in the right thalamus and midpons (P < .05) and trended lower in the midtemporal, left thalamus, and anterior vermis regions (P < .1) in preterm infants with brain injury. Regional CBF in preterm infants with moderate-severe brain injury trended lower in the midpons, right cerebellar hemisphere, and dentate nuclei compared with mild brain injury (P < .1). In addition, a significant, lower regional CBF was associated with ventilation, sepsis, and cesarean delivery (P < .05).

CONCLUSIONS

We report early disturbances in global and regional CBF in preterm infants following brain injury. Regional cerebral perfusion alterations were evident in the thalamus and pons, suggesting regional vulnerability of the developing cerebro-cerebellar circuitry.

Sonographic evaluation of immobility of normal and endometriotic ovary in detection of deep endometriosis

OBJECTIVES

To examine the association between ovarian immobility and presence of endometriomas and assess the diagnostic accuracy of transvaginal sonographic (TVS) ovarian immobility in the detection of deep infiltrating endometriosis (DIE).

METHODS

This was a multicenter prospective observational study of women presenting with chronic pelvic pain from January 2009 to March 2015. Women with or without history of endometriosis who were scheduled to undergo laparoscopic surgery for endometriosis gave a detailed history and underwent specialized TVS in a tertiary referral unit prior to laparoscopy. During TVS, ovarian mobility and the presence of endometriomas were assessed. The relationship between TVS ovarian mobility, with or without endometriomas, and DIE was correlated with the gold standard, diagnosis of endometriosis at laparoscopy.

RESULTS

Included in the analysis were 265 women with preoperative TVS and laparoscopic outcomes. Ovarian immobility on TVS was significantly associated with presence of endometriomas at surgery, with a prevalence of 12.2%, 10.8% and 52.7% for fixation of the left ovary only, the right ovary only and bilateral ovaries, respectively, compared with 4.2%, 3.7% and 7.3% for normal ovaries. The sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and positive and negative likelihood ratios of TVS ovarian immobility for diagnosis at surgery of immobility of ovaries with endometriomas in the left ovary only were 44.4%, 92.3%, 44.4%, 92.3%, 5.8, 0.6, in the right ovary only were 50.0%, 98.5%, 80.0%, 94.2%, 33.0, 0.5 and bilaterally were 74.4%, 68.6%, 72.5%, 70.6%, 2.4, 0.4, while those for diagnosis of immobility of normal ovaries were 25.0%, 87.9%, 8.3%, 96.4%, 2.1, 0.9 for left ovary only, 14.3%, 92.9%, 7.1%, 96.6%, 2.0, 0.9 for right ovary only and 35.7%, 97.2%, 50.0%, 95.0%, 12.6, 0.7 bilaterally, respectively (P < 0.05 except for normal left and right ovaries with P = 0.2 and 0.4, respectively). The sensitivity, specificity, PPV and NPV for performance of ovarian immobility in the prediction of DIE for all women were 58.3%, 74.1%, 60.6%, 72.2% and in the prediction of need for bowel surgery were 78.2%, 71.1%, 41.3%, 92.6%, respectively.

CONCLUSIONS

There is a significant association between ovarian immobility and the presence of endometriomas. Ovarian immobility as a sonographic 'soft marker' of DIE performs better in the presence of endometriomas compared with in normal ovaries. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Craniopharyngioma presenting with severe hyponatremia, hyponatremia-induced myopathy, and panhypopituitarism: a case report

Background

Craniopharyngiomas are rare intracranial tumors commonly presenting with neurological symptoms. Reports of severe hyponatremia as a presenting manifestation of a craniopharyngioma and hyponatremia-induced myopathy are rare. We report the case of a patient with craniopharyngioma presenting with severe hyponatremia, panhypopituitarism, and hyponatremia-induced myopathy.

Case presentation

A 52-year-old Sri Lankan man presented with anorexia, nausea, fatigue, generalized muscle weakness, and cramps for 1 week. The onset of his illness had been preceded by vomiting and diarrhea for 1 day which he attributed to food poisoning. On examination, he had an apathetic disposition with a generalized “sallow complexion.” He was not dehydrated. Apart from reduced muscle power (4/5) and hyporeflexia, the neurological examination was normal. His serum sodium was 102 mmol/l; potassium 4.1 mmol/l; chloride 63 mmol/l; plasma osmolality 272 mosm/KgH₂O; urine osmolality 642 mosm/KgH₂O; and urine sodium 79 mmol/l. His creatine phosphokinase was 12,400 U/l, lactate dehydrogenase 628 U/l, aspartate aminotransferase 360 U/l, and alanine aminotransferase 64 U/l. His hormone profile revealed panhypopituitarism. An electromyogram showed nonspecific abnormalities while a muscle biopsy did not show any pathology. Magnetic resonance imaging of his brain demonstrated a well-defined craniopharyngioma with suprasellar extension. His pituitary gland was compressed and the pituitary stalk was displaced by the tumor. He had marked improvement in muscle power and rapid reduction of serum creatine phosphokinase levels paralleling the correction of severe hyponatremia, even before the initiation of hormone replacement.

Conclusions

This case illustrates the rare presentation of severe hyponatremia and hyponatremia-induced myopathy in patients with craniopharyngioma, awareness of which would facilitate early appropriate investigations and treatment.

Lung Deposits of Lipiodol in Normal and Cirrhotic Rats

The distribution of Lipiodol in the liver and lungs following arterial or portal injection was studied in normal (n = 55) and cirrhotic rats (n = 20). Using magnified xeroradiography and radioisotope labeled tracers, it was found that Lipiodol was deposited mainly in the liver and lung after either arterial or portal administration. In control rats after arterial injection, deposits in the lung peaked after 2 hours and gradually declined over 48 hours; whereas after portal injection, the deposit steadily increased for 48 hours. Twenty-five percent of cirrhotic rats demonstrated a Lipiodol-induced miliary pattern in the lung. An increased number of portosystemic shunts in cirrhotic rats was also noted. These results suggest that cirrhosis of the liver may be a potential risk factor for developing pulmonary complications after Lipiodol administration.