Implementation of artificial intelligence for the detection of cutaneous melanoma within a primary care setting: prevalence and types of skin cancer in outdoor enthusiasts

Background

There is enthusiasm for implementing artificial intelligence (AI) to assist clinicians detect skin cancer. Performance metrics of AI from dermoscopic images have been promising, with studies documenting sensitivity and specificity values equal to or superior to specialists for the detection of malignant melanomas (MM). Early detection rates would particularly benefit Australia, which has the worlds highest incidence of MM per capita. The detection of skin cancer may be delayed due to late screening or the inherent difficulty in diagnosing early skin cancers which often have a paucity of clinical features and may blend into sun damaged skin. Individuals who participate in outdoor sports and recreation experience high levels of intermittent ultraviolet radiation (UVR), which is associated with the development of skin cancer, including MM. This research aimed to assess the prevalence of skin cancer in individuals who regularly participate in activities outdoors and to report the performance parameters of a commercially available AI-powered software to assess the predictive risk of MM development.

Methods

Cross-sectional study design incorporating a survey, total body skin cancer screening and AI-embedded software capable of predictive scoring of queried MM.

Results

A total of 423 participants consisting of surfers (n = 108), swimmers (n = 60) and walkers/runners (n = 255) participated. Point prevalence for MM was highest for surfers (6.48%), followed by walkers/runners (4.3%) and swimmers (3.33%) respectively. When compared to the general Australian population, surfers had the highest odds ratio (OR) for MM (OR 119.8), followed by walkers/runners (OR 79.74), and swimmers (OR 61.61) rounded out the populations. Surfers and swimmers reported comparatively lower lifetime hours of sun exposure (5,594 and 5,686, respectively) but more significant amounts of activity within peak ultraviolet index compared with walkers/runners (9,554 h). A total of 48 suspicious pigmented lesions made up of histopathology-confirmed MM (n = 15) and benign lesions (n = 33) were identified. The performance of the AI from this clinical population was found to have a sensitivity of 53.33%, specificity of 54.44% and accuracy of 54.17%.

Conclusions

Rates of both keratinocyte carcinomas and MM were notably higher in aquatic and land-based enthusiasts compared to the general Australian population. These findings further highlight the clinical importance of sun-safe protection measures and regular skin screening in individuals who spend significant time outdoors. The use of AI in the early identification of MM is promising. However, the lower-than-expected performance metrics of the AI software used in this study indicated reservations should be held before recommending this particular version of this AI software as a reliable adjunct for clinicians in skin imaging diagnostics in patients with potentially sun damaged skin.

Peripheral Blood Flow Cytometry Outside of Recommended Indications: A Potential Source of Increased Healthcare Costs?

Introduction/Objective

Flow cytometry (FC) is a useful tool in the diagnosis of hematological conditions. Recommended indications for peripheral blood FC have been put forth by several groups, including the American Society for Clinical Pathology (ASCP) in its Choosing Wisely Initiative, and include neutropenia, absolute lymphocytosis, lymphadenopathy and splenomegaly, as well as follow-up for known hematological malignancies. Concerns exist that the use of peripheral blood flow cytometry outside of these indications can be associated with increased health costs.

Methods/Case Report

We performed a retrospective search for all peripheral blood flow cytometry studies performed at Rush University Medical Center in the period spanning January to June, 2021. We used the Query feature on Soft Computer’s SoftFlow (SCC Soft Computer, Florida). For all cases found the electronic health record was searched for information on the clinical indication, ordering service, history of hematological malignancies, and study results.

Results (if a Case Study enter NA)

286 peripheral blood flow cytometry studies were identified, of which 187 had negative findings and 99 were abnormal. 220 cases (77%) were ordered under recommended indications (by ASCP) while 66 cases (23%) were ordered outside of them. Of the studies ordered under recommended indications, 121 (55%) had abnormal findings, while 99 (45%) were negative. Of the studies ordered outside of recommended indications, 100% had negative findings; none of these cases showed a history of hematological malignancy on record. The most common non-recommended indications were isolated anemia (31 cases, 11%), isolated thrombocytopenia (16 cases, 5.5%), bicytopenia (15 cases, 5%) and coagulopathy (4 cases, 1.5%). 42 studies (65%) were ordered by the hematology/oncology service while 22 (35%) were ordered by the internal medicine and surgery services.

Conclusion

A quarter of the peripheral blood flow cytometry studies in the selected period were performed outside of recommended indications, with negative results in 100% of them. Collectively, single or bicytopenias were the most common non-recommended indication. The majority of these studies were ordered by the hematology/oncology service, with only a third coming from others. Some possible causes for these inappropriate requests include ordering studies as a battery instead of a step-wise approach, and concern for missing an incipient/occult condition.

Defining mitochondrial protein functions through deep multiomic profiling

Mitochondria are epicentres of eukaryotic metabolism and bioenergetics. Pioneering efforts in recent decades have established the core protein componentry of these organelles1 and have linked their dysfunction to more than 150 distinct disorders2,3. Still, hundreds of mitochondrial proteins lack clear functions4, and the underlying genetic basis for approximately 40% of mitochondrial disorders remains unresolved5. Here, to establish a more complete functional compendium of human mitochondrial proteins, we profiled more than 200 CRISPR-mediated HAP1 cell knockout lines using mass spectrometry-based multiomics analyses. This effort generated approximately 8.3 million distinct biomolecule measurements, providing a deep survey of the cellular responses to mitochondrial perturbations and laying a foundation for mechanistic investigations into protein function. Guided by these data, we discovered that PIGY upstream open reading frame (PYURF) is an S-adenosylmethionine-dependent methyltransferase chaperone that supports both complex I assembly and coenzyme Q biosynthesis and is disrupted in a previously unresolved multisystemic mitochondrial disorder. We further linked the putative zinc transporter SLC30A9 to mitochondrial ribosomes and OxPhos integrity and established RAB5IF as the second gene harbouring pathogenic variants that cause cerebrofaciothoracic dysplasia. Our data, which can be explored through the interactive online MITOMICS.app resource, suggest biological roles for many other orphan mitochondrial proteins that still lack robust functional characterization and define a rich cell signature of mitochondrial dysfunction that can support the genetic diagnosis of mitochondrial diseases.

Large-Scale Multi-omic Analysis of COVID-19 Severity

We performed RNA-seq and high-resolution mass spectrometry on 128 blood samples from COVID-19-positive and COVID-19-negative patients with diverse disease severities and outcomes. Quantified transcripts, proteins, metabolites, and lipids were associated with clinical outcomes in a curated relational database, uniquely enabling systems analysis and cross-ome correlations to molecules and patient prognoses. We mapped 219 molecular features with high significance to COVID-19 status and severity, many of which were involved in complement activation, dysregulated lipid transport, and neutrophil activation. We identified sets of covarying molecules, e.g., protein gelsolin and metabolite citrate or plasmalogens and apolipoproteins, offering pathophysiological insights and therapeutic suggestions. The observed dysregulation of platelet function, blood coagulation, acute phase response, and endotheliopathy further illuminated the unique COVID-19 phenotype. We present a web-based tool (covid-omics.app) enabling interactive exploration of our compendium and illustrate its utility through a machine learning approach for prediction of COVID-19 severity.

Argonaut: A Web Platform for Collaborative Multi-omic Data Visualization and Exploration

Researchers now generate large multi-omic datasets using increasingly mature mass spectrometry techniques at an astounding pace, facing new challenges of "Big Data" dissemination, visualization, and exploration. Conveniently, web-based data portals accommodate the complexity of multi-omic experiments and the many experts involved. However, developing these tailored companion resources requires programming expertise and knowledge of web server architecture-a substantial burden for most. Here, we describe Argonaut, a simple, code-free, and user-friendly platform for creating customizable, interactive data-hosting websites. Argonaut carries out real-time statistical analyses of the data, which it organizes into easily sharable projects. Collaborating researchers worldwide can explore the results, visualized through popular plots, and modify them to streamline data interpretation. Increasing the pace and ease of access to multi-omic data, Argonaut aims to propel discovery of new biological insights. We showcase the capabilities of this tool using a published multi-omics dataset on the large mitochondrial protease deletion collection.

A large-scale genome-lipid association map guides lipid identification

Despite the crucial roles of lipids in metabolism, we are still at the early stages of comprehensively annotating lipid species and their genetic basis. Mass spectrometry-based discovery lipidomics offers the potential to globally survey lipids and their relative abundances in various biological samples. To discover the genetics of lipid features obtained through high-resolution liquid chromatography-tandem mass spectrometry, we analysed liver and plasma from 384 diversity outbred mice, and quantified 3,283 molecular features. These features were mapped to 5,622 lipid quantitative trait loci and compiled into a public web resource termed LipidGenie. The data are cross-referenced to the human genome and offer a bridge between genetic associations in humans and mice. Harnessing this resource, we used genome-lipid association data as an additional aid to identify a number of lipids, for example gangliosides through their association with B4galnt1, and found evidence for a group of sex-specific phosphatidylcholines through their shared locus. Finally, LipidGenie's ability to query either mass or gene-centric terms suggests acyl-chain-specific functions for proteins of the ABHD family.

Large-scale Multi-omic Analysis of COVID-19 Severity

We performed RNA-Seq and high-resolution mass spectrometry on 128 blood samples from COVID-19 positive and negative patients with diverse disease severities. Over 17,000 transcripts, proteins, metabolites, and lipids were quantified and associated with clinical outcomes in a curated relational database, uniquely enabling systems analysis and cross-ome correlations to molecules and patient prognoses. We mapped 219 molecular features with high significance to COVID-19 status and severity, many involved in complement activation, dysregulated lipid transport, and neutrophil activation. We identified sets of covarying molecules, e.g., protein gelsolin and metabolite citrate or plasmalogens and apolipoproteins, offering pathophysiological insights and therapeutic suggestions. The observed dysregulation of platelet function, blood coagulation, acute phase response, and endotheliopathy further illuminated the unique COVID-19 phenotype. We present a web-based tool (covid-omics.app) enabling interactive exploration of our compendium and illustrate its utility through a comparative analysis with published data and a machine learning approach for prediction of COVID-19 severity.

Real-time health monitoring through urine metabolomics

Current healthcare practices are reactive and based on limited physiological information collected months or years apart. By enabling patients and healthy consumers access to continuous measurements of health, wearable devices and digital medicine stand to realize highly personalized and preventative care. However, most current digital technologies provide information on a limited set of physiological traits, such as heart rate and step count, which alone offer little insight into the etiology of most diseases. Here we propose to integrate data from biohealth smartphone applications with continuous metabolic phenotypes derived from urine metabolites. This combination of molecular phenotypes with quantitative measurements of lifestyle reflect the biological consequences of human behavior in real time. We present data from an observational study involving two healthy subjects and discuss the challenges, opportunities, and implications of integrating this new layer of physiological information into digital medicine. Though our dataset is limited to two subjects, our analysis (also available through an interactive web-based visualization tool) provides an initial framework to monitor lifestyle factors, such as nutrition, drug metabolism, exercise, and sleep using urine metabolites.

Learning Drug Functions from Chemical Structures with Convolutional Neural Networks and Random Forests

Empirical testing of chemicals for drug efficacy costs many billions of dollars every year. The ability to predict the action of molecules in silico would greatly increase the speed and decrease the cost of prioritizing drug leads. Here, we asked whether drug function, defined as MeSH "therapeutic use" classes, can be predicted from only a chemical structure. We evaluated two chemical-structure-derived drug classification methods, chemical images with convolutional neural networks and molecular fingerprints with random forests, both of which outperformed previous predictions that used drug-induced transcriptomic changes as chemical representations. This suggests that the structure of a chemical contains at least as much information about its therapeutic use as the transcriptional cellular response to that chemical. Furthermore, because training data based on chemical structure is not limited to a small set of molecules for which transcriptomic measurements are available, our strategy can leverage more training data to significantly improve predictive accuracy to 83-88%. Finally, we explore use of these models for prediction of side effects and drug-repurposing opportunities and demonstrate the effectiveness of this modeling strategy for multilabel classification.

Autometa: automated extraction of microbial genomes from individual shotgun metagenomes

Shotgun metagenomics is a powerful, high-resolution technique enabling the study of microbial communities in situ. However, species-level resolution is only achieved after a process of 'binning' where contigs predicted to originate from the same genome are clustered. Such culture-independent sequencing frequently unearths novel microbes, and so various methods have been devised for reference-free binning. As novel microbiomes of increasing complexity are explored, sometimes associated with non-model hosts, robust automated binning methods are required. Existing methods struggle with eukaryotic contamination and cannot handle highly complex single metagenomes. We therefore developed an automated binning pipeline, termed 'Autometa', to address these issues. This command-line application integrates sequence homology, nucleotide composition, coverage and the presence of single-copy marker genes to separate microbial genomes from non-model host genomes and other eukaryotic contaminants, before deconvoluting individual genomes from single metagenomes. The method is able to effectively separate over 1000 genomes from a metagenome, allowing the study of previously intractably complex environments at the level of single species. Autometa is freely available at https://bitbucket.org/jason_c_kwan/autometa and as a docker image at https://hub.docker.com/r/jasonkwan/autometa under the GNU Affero General Public License 3 (AGPL 3).

An antifungal polyketide associated with horizontally acquired genes supports symbiont-mediated defense in Lagria villosa beetles

Microbial symbionts are often a source of chemical novelty and can contribute to host defense against antagonists. However, the ecological relevance of chemical mediators remains unclear for most systems. Lagria beetles live in symbiosis with multiple strains of Burkholderia bacteria that protect their offspring against pathogens. Here, we describe the antifungal polyketide lagriamide, and provide evidence supporting that it is produced by an uncultured symbiont, Burkholderia gladioli Lv-StB, which is dominant in field-collected Lagria villosa. Interestingly, lagriamide is structurally similar to bistramides, defensive compounds found in marine tunicates. We identify a gene cluster that is probably involved in lagriamide biosynthesis, provide evidence for horizontal acquisition of these genes, and show that the naturally occurring symbiont strains on the egg are protective in the soil environment. Our findings highlight the potential of microbial symbionts and horizontal gene transfer as influential sources of ecological innovation.

Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI): Instrument Design and Calibration

The Michelson Interferometer for Global High-resolution imaging of the Thermosphere and Ionosphere (MIGHTI) instrument was built for launch and operation on the NASA Ionospheric Connection Explorer (ICON) mission. The instrument was designed to measure thermospheric horizontal wind velocity profiles and thermospheric temperature in altitude regions between 90km and 300km, during day and night. For the wind measurements it uses two perpendicular fields of view pointed at the Earth's limb, observing the Doppler shift of the atomic oxygen red and green lines at 630.0nm and 557.7nm wavelength. The wavelength shift is measured using field-widened, temperature compensated Doppler Asymmetric Spatial Heterodyne (DASH) spectrometers, employing low order échelle gratings operating at two different orders for the different atmospheric lines. The temperature measurement is accomplished by a multichannel photometric measurement of the spectral shape of the molecular oxygen A-band around 762nm wavelength. For each field of view, the signals of the two oxygen lines and the A-band are detected on different regions of a single, cooled, frame transfer charge coupled device (CCD) detector. On-board calibration sources are used to periodically quantify thermal drifts, simultaneously with observing the atmosphere. The MIGHTI requirements, the resulting instrument design and the calibration are described.

Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI): Monolithic Interferometer Design and Test

The design and laboratory tests of the interferometers for the Michelson Interferometer for Global High-resolution Thermospheric Imaging (MIGHTI) instrument which measures thermospheric wind and temperature for the NASA-sponsored Ionospheric Connection (ICON) Explorer mission are described. The monolithic interferometers use the Doppler Asymmetric Spatial Heterodyne (DASH) Spectroscopy technique for wind measurements and a multi-element photometer approach to measure thermospheric temperatures. The DASH technique and overall optical design of the MIGHTI instrument are described in an overview followed by details on the design, element fabrication, assembly, laboratory tests and thermal control of the interferometers that are the heart of MIGHTI.

Microbial community response of nitrifying sequencing batch reactors to silver, zero-valent iron, titanium dioxide and cerium dioxide nanomaterials

As nanomaterials in consumer products increasingly enter wastewater treatment plants, there is concern that they may have adverse effects on biological wastewater treatment. Effects of silver (nanoAg), zero-valent iron (NZVI), titanium dioxide (nanoTiO₂) and cerium dioxide (nanoCeO₂) nanomaterials on nitrification and microbial community structure were examined in duplicate lab-scale nitrifying sequencing batch reactors (SBRs) relative to control SBRs that received no nanomaterials or ionic/bulk analogs. Nitrification function was not measurably inhibited in the SBRs by any of the materials as dosing was initiated at 0.1 mg/L and sequentially increased every 14 days to 1, 10, and 20 mg/L. However, SBRs rapidly lost nitrification function when the Ag⁺ experiment was repeated at a continuous high load of 20 mg/L. Shifts in microbial community structure and decreased microbial diversity were associated with both sequential and high loading of nanoAg and Ag⁺, with more pronounced effects for Ag⁺. Bacteroidetes became more dominant in SBRs dosed with Ag⁺, while Proteobacteria became more dominant in SBRs dosed with nanoAg. The two forms of silver also had distinct effects on specific bacterial genera. A decrease in nitrification gene markers (amoA) was observed in SBRs dosed with nanoAg and Ag⁺. In contrast, impacts of NZVI, nanoTiO₂, nanoCeO₂ and their analogs on microbial community structure and nitrification gene markers were limited. TEM-EDS analysis indicated that a large portion of nanoAg remained dispersed in the activated sludge and formed Ag–S complexes, while NZVI, nanoTiO₂ and nanoCeO₂ were mostly aggregated and chemically unmodified. Overall, this study suggests a high threshold of the four nanomaterials in terms of exerting adverse effects on nitrification function. However, distinct microbial community responses to nanoAg indicate potential long-term effects.

The use of silicon-based tethers for the Pauson-Khand reaction

A range of silicon-based tethers and promoters have been investigated for use in the development of a silyl-tethered Pauson-Khand reaction.

The effect of UV absorbing sunscreens on the reflectance and the consequent protection of skin

The in vivo reflectance spectra of Caucasian skin, coated with preparations containing sunscreen vehicle, vehicle with olive oil and vehicle with the UVB and UVA absorbers 2-ethylhexyl-4-methoxycinnamate and 4-t-butyl-4'-methoxydibenzoylmethane were determined. All preparations reduced the reflectance of skin throughout the UVA spectral range (320 to 400 nm), with the sunscreen preparations containing the UVB and UVB plus UVA absorbers reducing the reflectance more than the sunscreen vehicle alone. This phenomenon, which facilitates the penetration of UV radiation to the lower epidermis and dermal layers of skin and therefore lessens sunscreen efficacy, is attributed to optical coupling mediated by refractive index matching of the sunscreen to the upper epidermis. The greater reduction in skin diffuse reflectance caused by sunscreens containing methoxycinnamate is associated with this compound's high refractive index. Also, by determining the excitation spectra of the autofluorescence originating from the dermal layer of skin, the transmission spectra of the various components of sunscreen on skin were established, and these were in good general agreement with previously published spectra.

RNA-binding protein TIAR is essential for primordial germ cell development

Primordial germ cells (PGCs) give rise to both eggs and sperm via complex maturational processes that require both cell migration and proliferation. However, little is known about the genes controlling gamete formation during the early stages of PGC development. Although several mutations are known to severely reduce the number of PGCs reaching and populating the genital ridges, the molecular identity of only two of these genes is known: the c-kit receptor protein tyrosine kinase and the c-kit ligand (the steel factor). Herein, we report that mutant mice lacking TIAR, an RNA recognition motif/ribonucleoprotein-type RNA-binding protein highly expressed in PGCs, fail to develop spermatogonia or oogonia. This developmental defect is a consequence of reduced survival of PGCs that migrate to the genital ridge around embryonic day 11.5 (E11.5). The numbers of PGCs populating the genital ridge in TIAR-deficient embryos are severely reduced compared to wild-type embryos by E11.5 and in the mutants PGCs are completely absent at E13.5. Furthermore, TIAR-deficient embryonic stem cells do not proliferate in the absence of exogenous leukemia inhibitory factor in an in vitro methylcellulose culture assay, supporting a role for TIAR in regulating cell proliferation. Because the development of PGCs relies on the action of several growth factors, these results are consistent with a role for TIAR in the expression of a survival factor or survival factor receptor that is essential for PGC development. TIAR-deficient mice thus provide a model system to study molecular mechanisms of PGC development and possibly the basis for some forms of idiopathic infertility.

Semiclassical Quantum Mechanics, Bond Delocalization and the Mills - Nixon Effect

Conjugated π electrons in a ring system are described in terms of a transverse wave propagated along the carbon skeleton. Kekule benzene is forbidden because the π electron quantal wave self-interferes. The characteristics of an aromatic system are expressed in terms of the weighted combination of Kekule structures, and resonance energy occurs through combining canonical structures with conservation of momentum. The resonance energy of benzene is calculated as 1·045 times the energy difference between two carbon-carbon single bonds and one double bond, or 162 kJ/mol on one bond energy scheme. Bond localization is due to differences in wave impedance between zones represented by adjacent phase space cells; wave reinforcement occurs in one zone, cancellation in another as a consequence of the directional asymmetry of phase changes of the quantal wave. Quantal wave impedance can be altered by altering the localized potential, and it is proposed that the so-called Mills-Nixon effect arising from the annelation of bicyclic rings occurs because the bicyclic ring better focuses a polarization field. The polarization field arising as a consequence of strain is shown to semiquantitatively account for the bond alternation. The difference between exo and endo bond lengths in tris(bicyclo[2.1.1]hexeno)benzene is calculated to be 7·2 pm, compared with 9 pm as determined experimentally.

Acid-induced laryngospasm in a canine model

A canine model was used to investigate the efferent laryngeal responses to stimulation by topically applied acid and pepsin. Five adult mongrel dogs were studied. Electromyographic recordings from the thyroarytenoid muscle were measured with hooked-wire electrodes as an acid solution (normal saline/hydrochloric acid at pH 6.0, 5.0, 4.0, 3.0, 2.5, 2.0, 1.5, and 1.0) was sequentially instilled into the larynx. Laryngospasm (tonic, sustained contraction of the thyroarytenoid muscle) occurred in all animals at pH 2.5 to 2.0 or less. Control substances such as neutral pH isotonic saline, hypotonic saline, hypertonic saline, water, and pepsin alone failed to produce laryngospasm. Next, solutions containing both acid (in the same pH range) and pepsin were tested. The laryngeal responses were similar to those of acid alone. The superior laryngeal nerves were sectioned bilaterally and the above experiments repeated. None of the test solutions produced laryngospasm; however, when capsaicin (1%) was instilled into the subglottis, laryngospasm occurred. Thus, chemoreceptors in the subglottis (supplied by the recurrent laryngeal nerves) appear to be responsive to capsaicin stimulation but not to acid stimulation. The data suggest that pH-sensitive chemoreceptors in the canine larynx cause laryngospasm (when the pH of the test solution is 2.5 or less) and that these acid receptors are supplied by the superior laryngeal nerves.

Home hemodialysis: patient outcomes during a 24-year period of time from 1970 through 1993

In the United States, from 1983 to 1993, home hemodialysis use has decreased from 6% to 1.3% of the dialysis population, whereas continuous ambulatory peritoneal dialysis (CAPD) has increased to 20%. Most home hemodialysis programs have withered away because of current patient mix, increase in CAPD, proliferation of outpatient centers, disinterest in nephrologists, and fear of self-cannulation by patients. From 1970 through 1993, 896 patients began dialysis at North Shore and were followed up through 1994. During this period, 687 patients were on in-center hemodialysis, 95 on CAPD, 74 on home hemodialysis, and 40 on in-center peritoneal dialysis. The home hemodialysis patients were younger, with a median age of 44 versus 59 years for in-center hemodialysis patients, and had less comorbidity. The home hemodialysis group had fewer diabetic patients and no renal vascular patients. The 5-year and median survival estimates were significantly better for the home hemodialysis patients versus other dialysis modalities. More home hemodialysis patients received transplants. Compared with the other dialysis modalities, home hemodialysis patients showed significantly improved survival rates. When matched by age, sex, and end-stage renal disease (ESRD) diagnosis to corresponding in-center hemodialysis, the home hemodialysis patients still had significantly better survival rates, but the home hemodialysis patients had less comorbidity. In conclusion, home hemodialysis patients survive longer and have better rehabilitation than other dialysis patients. Reasons for better survival in addition to a younger age and more favorable ESRD diagnosis may include less comorbidity, more patient involvement, and longer dialysis time. Because of these better outcomes, home hemodialysis should be offered to more ESRD patients.

Structural analysis of the polysaccharide from Pachymenia lusoria (Cryptonemiaceae, Rhodophyta)

The highly complex polysaccharide extracted from the New Zealand red alga Pachymenia lusoria (Grev.) J. Ag. has been characterised and certain structural features defined. A reductive hydrolysis procedure was used for constituent sugar and linkage analyses, with trideuteriomethylation being employed to enable the location of natural methyl ether groups to be determined. A reductive partial-hydrolysis procedure allowed agarobiosyl constituent residues to be identified. The analytical results are consistent with the polymer having a linear backbone of 3-linked D-galactopyranosyl alternating with 4-linked D- or L-galactopyranosyl residues. The 3-linked residues are nearly all 2-sulfated, with 1 in 3 also being 6-O-methylated and 1 in 5 also bearing a 4,6-pyruvic acetal residue. About one-third of the polymer is comprised of blocks of agarobiosyl repeat units that are 2-sulfated on the beta-D-galactopyranosyl and one-third 2-O-methylated on the 3,6-anhydro-L-galactosyl constituents. Of the remaining 4-linked residues, half are 2-O-methyl-D-galactopyranosyl residues and half are galactopyranosyl residues, of which approximately half are in the L configuration.

Effects of chorda-lingual nerve injury and repair on human taste

Citric acid detection threshold and magnitude response were measured on the anterior tongue in 10 patients with unilateral chorda-lingual nerve transections before and after repair. Fungiform taste buds were analysed by videomicroscopy. Preliminary data suggests that humans can regenerate fungiform taste buds and recover some taste sensitivity after repair.

PTC/PROP tasting: anatomy, psychophysics, and sex effects

Taste worlds of humans vary because of taste blindness to phenylthiocarbamide (PTC) and its chemical relative, 6-n-propylthiouracil (PROP). We review early PTC studies and apply modern statistical analyses to show that a higher frequency of women tasted PTC crystals, and were tasters (threshold classification). In our laboratory, scaling of PROP bitterness led to the identification of a subset of tasters (supertasters) who rate PROP as intensely bitter. Supertasters also perceive stronger tastes from a variety of bitter and sweet substances, and perceive more burn from oral irritants (alcohol and capsaicin). The density of taste receptors on the anterior tongue (fungiform papillae, taste buds) correlate significantly with perceived bitterness of PROP and support the supertaster concept. Psychophysical data from studies in our laboratory also show a sex effect; women are supertasters more frequently. The anatomical data also support the sex difference; women have more fungiform papillae and more taste buds. Future investigations of PTC/PROP tasting and food behaviors should include scaling to identify supertasters and separate sex effects.

A novel, erythroid cell-specific murine transcription factor that binds to the CACCC element and is related to the Krüppel family of nuclear proteins

We describe a novel erythroid cell-specific cDNA (EKLF [erythroid Krüppel-like factor]) isolated by enriching for genes expressed in a mouse erythroleukemia cell line but not expressed in a mouse monocyte-macrophage cell line. The complete cDNA sequence is predicted to encode a protein of approximately 38,000 Da that contains a proline-rich amino domain and three TFIIIA-like zinc fingers within the carboxy domain. Additional sequence analyses reveal that the EKLF zinc fingers are most homologous to the Krüppel family of transcription factors and also allow us to predict potential DNA-binding target sites for the EKLF protein. On the basis of this prediction, we show that EKLF is able to bind the sequence CCA CAC CCT, an essential element of the beta-globin promoter. Its tissue distribution establishes that the EKLF transcript is expressed only in bone marrow and spleen, the two hematopoietic organs of the mouse, and analysis of murine cell lines indicates that EKLF expression is limited to erythroid and mast cell lines. Cotransfection assays establish that EKLF transcriptionally activates a target promoter that contains its DNA-binding site. The tissue expression pattern of EKLF, in conjunction with its function as a transcriptional activator, strongly suggests that the EKLF protein may be intimately involved in establishment and/or maintenance of the erythroid cell phenotype.

Comparative lectin histochemistry on taste buds in foliate, circumvallate and fungiform papillae of the rabbit tongue

Taste buds (TB) in the foliate, circumvallate and fungiform papillae of the rabbit tongue were examined with lectin histochemistry by means of light (LM) and electron (EM) microscopy. Biotin- and gold-labeled lectins were used for the detection of carbohydrate residues in TB cells and subcutaneous salivary glands. At the LM level, the lectins of soybean (SBA) and peanut (PNA) react with material of the foliate and circumvallate taste pores only after pretreatment of the section with neuraminidase. This indicates that the terminal trisaccharide sequences are as follows: Sialic acid-Gal-GalNAc in O-glycosylated glycoproteins or Sialic acid-Gal-GlcNAc in N-glycosylated glycoproteins. In fungi-form taste buds the lectins of Dolichos biflorus (DBA) and Helix pomatia (HPA), also specific to GalNAc residues, are reactive without preincubation with neuraminidase. Wheat germ agglutinin (WGA), specific to GlcNAc, reacts with TBs of all papillae; and the lectin from Ulex europaeus (UEA I), specific to fucose, binds to individual TB cells. The presence of sialic acid may protect mucus or other glycoproteins in TB cells and inside the taste pore from premature enzymatic degradation. In a post-embedding EM procedure on LR-White-embedded tissue sections, only gold-labeled HPA was found to bind especially on membrane surfaces of the microvilli which protrude into the taste pore; however HPA did not bind to the electron-dense mucus inside the taste pore. The mucus situated in the trough and at the top of the adjacent epithelial cells also is strongly HPA-positive, but is of different origin and composition than that found in the taste pore. These results demonstrate distinct carbohydrate histochemical differences between fungiform and circumvallate/foliate taste buds. The different configuration of galactosyl residues and the occurrence of mannose in circumvallate and foliate TBs leads to the suggestion that the lectin reactivities of TBs are not only due to the presence of mucins, but also to N-linked glycoproteins, possibly with a hormone-like paraneuronal function. A possible relationship to v. Ebner glands in these papillae is discussed.

The therapeutic empathic communication (TEC) process

While the communication of empathy is thought to be a curative factor in psychotherapy, current conceptualizations usually focus on empathy as only an attitude or state of mind of the therapist. A five-stage model of therapeutic empathic communication is presented. The model is applied to analyzing the therapeutic impact of empathic communication in dynamic psychotherapy. Its usefulness is demonstrated in a case example.

Sucrose octaacetate-taster mice have more vallate taste buds than non-tasters

Taste buds were counted in two strains of mice which have been characterized in terms of their taste avoidance of the bitter-tasting substance, sucrose octaacetate (SOA). One strain (SWR/J) avoids SOA and is referred to as "taster' while the other strain (C57BL/6J) does not avoid SOA at the same concentration and is termed "non-taster'. The taster-strain contains a significantly greater number of taste buds in its vallate papillae than the non-tasters do. The relative number of taste buds which individual mice and humans possess probably contributes to the relative differences in their sensitivity and preference behaviors.

Gustatory responsiveness of fibers in the hamster glossopharyngeal nerve

1. Mammalian taste receptors are distributed within separate subpopulations, innervated by branches of cranial nerves VII, IX, and X. Most gustatory electrophysiology has focused on input from the fungiform papillae on the anterior portion of the tongue, carried by the chorda tympani branch of the VIIth nerve. However, only a small percentage of the taste buds are located in the fungiform papillae (approximately 18% in the hamster). There have been no studies on the hamster's IXth nerve, which innervates greater than 50% of its taste buds, and most other studies of IXth nerve function have employed only whole-nerve recording. 2. Action potentials were recorded from 83 individual fibers in the IXth nerve of the hamster. Stimuli were five concentrations each of sucrose, NaCl, HCl, and quinine hydrochloride (QHCl), all presented to every fiber at 37 degrees C. Responses were quantified as the number of impulses in 10 s minus the preceding 10 s of spontaneous activity. 3. Across these concentration series, HCl and QHCl were by far the most excitatory stimuli, with mean responses across all cells three to four times greater than those evoked by sucrose or NaCl. The order of effectiveness of the stimuli was H greater than Q much greater than N greater than S. 4. Of the 83 fibers, 56 were stimulated via the foliate papillae and 27 via the single vallate papilla. No fibers responded to both of these fields. There were generally no differences in the sensitivity of these two subpopulations of taste buds, except that QHCl was more effective when applied to the foliates. 5. A "total" response measure was derived by summing the excitatory responses to each stimulus across the entire concentration series. The fibers were then classified according to the best total response, resulting in 52 HCl-, 19 QHCl-, 8 sucrose- and 4 NaCl-best cells. Considering the slope of the concentration-response functions as a criterion for classification produced very similar results. The fiber classification varied somewhat with concentration, with more fibers categorized as HCl- and QHCl-best at the higher concentration levels. 6. Breadth of responsiveness was measured using the equation developed by Smith and Travers. At the concentrations used to examine hamster chorda tympani fibers, IXth nerve fibers were not very responsive and were quite narrowly tuned to the four taste qualities. At higher concentrations the fibers became more broadly responsive across the four stimuli.(ABSTRACT TRUNCATED AT 400 WORDS)

A comparison of the effects of bilateral sections of the chorda tympani nerve and extirpation of the submaxillary and sublingual salivary glands on the eating and drinking patterns of the rat

The chorda tympani nerve (CT) innervates the fungiform papillae on the tip of the tongue and has been considered an important nerve for the sense of taste. The CT also contains the parasympathetic supply to the submaxillary and sublingual salivary glands. Therefore, changes in taste or feeding behavior following bilateral sections of CT are caused by both degeneration of fungiform papillae and the inevitable partial desalivation of the rat. In the present experiments we compared the effects of bilateral chorda tympani nerve sections with extirpation of submaxillary and sublingual glands on daily home cage eating and drinking patterns in the rat. Before and after surgery we analyzed the daily eating and drinking patterns, including such measures as intake, bout number, bout length, interbout interval and rate of consumption during bouts. The results of desalivation and bilateral CT sections were indistinguishable. The most profound change was that eating bout duration was increased following surgery. Since food intake did not increase, the results indicate a marked loss in eating efficiency over the daily ingestion periods. Although the eating patterns of desalivated and chorda tympani sectioned rats are quite similar, the evidence is not compelling that they have the same physiological basis. A second experiment was designed to test the hypothesis that the atypical eating patterns observed following bilateral sectioning of CT were the direct result of partial desalivation resulting from the denervation of the salivary glands. In this experiment a unilateral section was made of one CT and it was shown that the eating behavior was not affected. Then the contralateral submaxillary and sublingual salivary glands were removed. This resulted in a six-fold increase in feeding bout length. In all cases a unilateral CT section combined with extirpation of the contralateral salivary glands resulted in rats whose eating behavior was indistinguishable from the earlier data following either the bilateral CT sections or bilateral desalivations. The conclusion is drawn that the eating irregularities noted following bilateral CT sections result from this partial desalivation. CT sections were verified by taste bud counts in the fungiform papillae and histological examinations were made of salivary glands in rats receiving CT sections.

Human taste bud density across adult age groups

Some of the subjective variability attributed to taste experience could be related to wide variations of taste bud density. Studies of taste perception show a direct relationship between sensation and the number of receptors. Taste bud densities are quantified in this study using light microscopy to reconstruct two regions of 18 human cadaver tongues. Specimens came from male and female cadavers representing three age groups: young adults, middle-aged adults, and older adults. The results show a range of more than 100-fold in taste bud density that is evenly distributed among age groups and sexes. The disparity is not attributable to the state of health of the adults prior to death, and it is corroborated in the literature. Differences in taste bud density that extend across age groups probably confound some inferences about the effects of aging on taste sensitivity that are derived from cross-sectional studies of human populations. It is not clear from the data whether or not human taste bud density in individuals and in populations is stable or changing with time.

The effect of bilateral sectioning of the chorda tympani and the greater superficial petrosal nerves on the sweet taste in the rat

The effects of bilateral deafferentation of the greater superficial petrosal (GSP) and the chorda tympani (CT) nerves on the ingestion of sucrose solutions were studied in rats. The rats received five daily sequential 30 second exposures for each sucrose concentration, and the average number of licks per exposure was calculated. Sucrose concentrations of 0.01, 0.03, 0.10, 0.32, and 1.00 M were presented in ascending order across days, both before and after bilateral sectioning of both the CT and the GSP nerves, the CT alone, the GSP alone, or a sham surgery. Prior to surgery, mean lick rate increased with increasing concentrations of sucrose. Following surgery, the rats with combined GSP and CT nerve sections showed a significant decrease in mean rate of licking to the sucrose solutions. The rats with GSP sections showed a similar decrease in mean lick rate to the sucrose solutions. Animals with sections of the CT nerve and sham-operated animals showed no significant reduction in mean lick rate to the sucrose solutions. These results indicate that the GSP nerve is important to the rat in reinforcing high lick rates to sucrose.

Variation in human fungiform taste bud densities among regions and subjects

Taste sensitivity is known to vary among regions of the tongue and between subjects. The distribution of taste buds on the human tongue is examined in this report to determine if interregional and intersubject variation of taste bud density might account for some of the variation in human taste sensitivity. The subjects were ten males, aged 22-80 years, who died from acute trauma or an acute cardiovascular episode. Specimens were obtained as anatomical gifts or from autopsy. A sample of tissue about 1 cm2 was taken from the tongue tip and midlateral region; frozen sections were prepared for light microscopy; and serial sections were examined by light microscopy to count the taste buds. The average taste bud (tb) density on the tongue tip was 116 tb/cm2 with a range from 3.6 to 514 among subjects. The number of gustatory papillae on the tip averaged 24.5 papillae/cm2 with a range from 2.4 to 80. Taste bud density in the midregion averaged 25.2 tb/cm2 (range: 0-85.9), and the mean number of gustatory papillae was 8.25/cm2 (range: 0-28). The mean number of taste buds per papilla was 3.8 +/- 2.2 (s.d.) on the tip and 2.6 +/- 1.5 (s.d.) on the midregion. Subjects with the highest taste bud densities on the tip also had the highest densities in the midregion and the highest number of taste buds per papilla. Taste bud density was 4.6 times higher on the tip than the midregion, which probably accounts for some of the regional difference in taste sensitivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of renal donation. Long-term clinical and biochemical follow-up of living donors in a single center

Forty-six renal donors who responded to a questionnaire and two additional donors with nephrotic syndrome and renal insufficiency were studied. The mean age was 46 +/- 2.0 years (mean +/- SE). Duration of follow-up was 6 +/- 0.5 years. Serum creatinine levels increased from 1.0 +/- 0.03 mg/dl before donation to 1.2 +/- 0.04 mg/dl at follow-up. The incidence of proteinuria (more than 150 mg over 24 hours) was 39 percent. The serum creatinine level was 1.0 +/- 0.08 mg/dl and 1.2 +/- 0.06 mg/dl in the proteinuric and nonproteinuric groups, respectively. The incidence of hypertension was 31 percent with a serum creatinine level of 1.1 +/- 0.11 mg/dl and 1.2 +/- 0.07 mg/dl in the hypertensive and normotensive groups, respectively. One patient with nephrotic syndrome had proliferative glomerulonephritis. It is concluded that renal donation is associated with a minimal but statistically significant increment in serum creatinine levels. The incidence of mild hypertension and proteinuria is increased, but impact on renal function is minimal as assessed by serum creatinine determination.

Quantitative taste bud distribution in the hamster

The distribution of taste buds was examined in hamsters to reveal the sources of convergent neural activity on taste neurons of the medulla and pons. A total of 723 taste buds was found in adult animals. Fungiform papillae contained 130 taste buds (18%). A single vallate papilla had 168 taste buds (23%). There were 230 taste buds (32%) located on bilateral foliate papillae. The palate contained 100 taste buds (14%) divided among the soft palate (88, 12%) and the incisal papilla (12, 2%). On the epiglottis and adjacent region of the esophagus were found 70 taste buds (10%). About 10 taste buds each were located on the buccal wall (1.4%), while the remaining 5 taste buds were found on the sublingual organ. Conclusions about information processing in central neurons of the gustatory system must reflect knowledge of diverse receptor populations and their interactions.

Localization of the motor neurons to the tensor tympani muscle

The localization of the motor neurons to the tensor tympani (TT) muscle was studied using the method of retrograde transport of horseradish peroxidase (HRP). After intramuscular injections of HRP, specifically labeled neurons were found in the ventral, parvocellular portion of the trigeminal motor nucleus. These cells had a medial relation to the rootlets of the trigeminal nerve and, rostrally, to the lateral lemniscus. The results are compared to those of other investigators and a generalization is suggested for the localization of these neurons which allows for species variation. Other incidental findings are also discussed.

A 13C N.M.R. study of some disaccharides from algal polysaccharides

The acid hydrolysis of agar, a partially methylated agar, and K-carrageenan initially gives the disaccharide resulting from cleavage of the link between the anhydrogalactose and the galactose units. A new method for isolating these disaccharides on a preparative scale is described, and their 13C n.m.r. spectra are listed and assigned.