Case report: Ultrasound diagnosis of fish bone penetration into the thyroid

Ultrasonography is useful in the diagnosis of foreign body migrations (eg, fish bones) into the soft tissues of the neck.

Validity and reliability of the reflux symptom score

OBJECTIVES/HYPOTHESIS

To develop and validate the Reflux Symptom Score (RSS), a self-administered patient-reported outcome questionnaire for patients with laryngopharyngeal reflux (LPR).

STUDY DESIGN

Prospective controlled study.

METHODS

A total of 113 patients with LPR were enrolled and treated with diet and 3 months of pantoprazole, alginate, and/or magaldrate depending on the LPR characteristics (acid, nonacid, or mixed). Eighty asymptomatic individuals completed the study. Patients and controls completed the RSS twice within a 7-day period to assess test-retest reliability. Internal consistency was measured using Cronbach's α for the RSS items in patients and controls. Validity was assessed by comparing the baseline RSS with the Reflux Symptom Index (RSI) and Voice Handicap Index (VHI). Seventy-seven patients completed the RSS at baseline and after 6 and 12 weeks of treatment to assess responsiveness to change. The RSS cutoff for determining the presence and absence of LPR was examined by receiver operating characteristic analysis.

RESULTS

Test-retest reliability (r_s = 0.921) and internal consistency reliability (α = 0.969) were high. RSS exhibited high external validity indicated by a significant correlation with the RSI (r_s = 0.831). Internal validity was excellent based on the higher RSS in patients compared with controls (P = .001). RSS, RSI, and VHI scores significantly improved from pre- to posttreatment, indicating a high responsiveness to change. RSS >13 can be considered suggestive of LPR-related symptoms. RSS was not influenced by the occurrence of gastroesophageal reflux disease, LPR subtypes, or patient characteristics.

CONCLUSIONS

RSS is a self-administered patient-reported outcome questionnaire that demonstrates high reliability and excellent criterion-based validity. RSS can be used in diagnosing and monitoring LPR disease.

LEVEL OF EVIDENCE

3b Laryngoscope, 130:E98-E107, 2020.

Encapsulating genetically modified Saccharomyces cerevisiae cells in a flow-through device towards the detection of diclofenac in wastewater

Recently it has been proposed to use sensors based on genetically engineered reporter cells to perform continuous online water monitoring. Here we describe the design, assembly and performance of a novel flow-through device with immobilized genetically modified yeast cells that produce a fluorescent protein upon stimulation with diclofenac whose intensity is then detected by fluorescence microscopy. Although other devices employing immobilized cells for the detection of various analytes have already been described before, as novelty our system allows safe enclosure of the sensor cells, and thus, to obtain fluorescent signals that are not falsified by a loss of cells. Furthermore, the yeast cells are prevented from being released into the environment. Despite the safe containment, the immobilized reporter cells are accessible to nutrients and analytes. They thus have both the ability to grow and respond to the analyte. Both in cell culture medium and standardized synthetic wastewater, we are able to differentiate between diclofenac concentrations in a range from 10 to 100 μM. As particularly interesting feature, we show that only the biologically active fraction of diclofenac is detected. Nowadays, contamination of wastewater with diclofenac and other pharmaceutical residues is becoming a severe problem. Our investigations may pave the way for an easy-to-use and cost-efficient wastewater monitoring method.

Somatic tinnitus prevalence and treatment with tinnitus retraining therapy

OBJECTIVES

Somatic tinnitus originates from increased activity of the dorsal cochlear nucleus, a cross-point between the somatic and auditory systems. Its activity can be modified by auditory stimulation or somatic system manipulation. Thus, sound enrichment and white noise stimulation might decrease tinnitus and associated somatic symptoms. The present uncontrolled study sought to determine somatic tinnitus prevalence among tinnitus sufferers, and to investigate whether sound therapy with counselling (tinnitus retraining therapy; TRT) may decrease tinnitus-associated somatic symptoms.

METHODS

To determine somatic tinnitus prevalence, 70 patients following the TRT protocol completed the Jastreboff Structured Interview (JSI) with additional questions regarding the presence and type of somatic symptoms. Among 21 somatic tinnitus patients, we further investigated the effects of TRT on tinnitus-associated facial dysesthesia. Before and after three months of TRT, tinnitus severity was evaluated using the Tinnitus Handicap Inventory (THI), and facial dysesthesia was assessed with an extended JSI-based questionnaire.

RESULTS

Among the evaluated tinnitus patients, 56% presented somatic tinnitus-including 51% with facial dysesthesia, 36% who could modulate tinnitus by head and neck movements, and 13% with both conditions. Self-evaluation indicated that TRT significantly improved tinnitus and facial dysesthesia in 76% of patients. Three months of TRT led to a 50% decrease in mean THI and JSI scores regarding facial dysesthesia.

CONCLUSIONS

Somatic tinnitus is a frequent and underestimated condition. We suggest an extension of the JSI, including specific questions regarding somatic tinnitus. TRT significantly improved tinnitus and accompanying facial dysesthesia, and could be a useful somatic tinnitus treatment.

Acute external ear lesions: clinical aspects, assessment and management

Acute external ear lesions: clinical aspects, assessment and management. We reviewed the literature concerning the assessment and the management of the external ear traumas, which is not very rich. Nevertheless, we outlined the practical attitudes in the four major conditions met: the auricular haematoma, the auricular perichondritis, the auricular laceration and auricular bums. All these pathologies must be promptly treated because there is a risk of perichondritis, which can destroy the cartilage and will result in a severely deformed ear. Auricular haematomas must be drained as soon as possible, lacerations with exposed cartilage must be stitched urgently, and burnt ears should be washed, coated with alginates (Flaminal@) and covered with a loose dressing. Antibioprophyl- axy should always be prescribed after a complete microbiological sampling.

Short-incubation mass spectrometry assay for lysosomal storage disorders in newborn and high-risk population screening

The interest in early detection strategies for lysosomal storage disorders (LSDs) in newborns and high-risk population has increased in the last years due to the availability of novel treatment strategies coupled with the development of diagnostic techniques. We report the development of a short-incubation mass spectrometry-based protocol that allows the detection of Gaucher, Niemann-Pick A/B, Pompe, Fabry and mucopolysaccharidosis type I disease within 4h including sample preparation from dried blood spots. Optimized sample handling without the need of time-consuming offline preparations, such as liquid-liquid and solid-phase extraction, allows the simultaneous quantification of five lysosomal enzyme activities using a cassette of substrates and deuterated internal standards. Applying incubation times of 3h revealed in intra-day CV% values ranging from 4% to 11% for all five enzyme activities, respectively. In a first clinical evaluation, we tested 825 unaffected newborns and 16 patients with LSDs using a multiplexed, turbulent flow chromatography-ultra high performance liquid chromatography-tandem mass spectrometer assay. All affected patients were identified accurately and could be differentiated from non-affected newborns. In comparison to previously published two-day assays, which included an overnight incubation, this protocol enabled the detection of lysosomal enzyme activities from sample to first result within half a day.

Possible association of severe major depression with acute cessation of long-term excessive triptan use

WHAT IS KNOWN AND OBJECTIVE

Triptans are approved medications introduced for the acute treatment of migraine, classified as high-affinity serotonin 5-HT(1B/D) receptor agonists with lower affinity for 5-HT(1A) receptors. Both migraine and treatment of migraine with triptans have been associated with the development of major depression. However, little is known about the adverse effects of acute cessation of long-term overdose triptan use.

CASE SUMMARY

We report a case of a 49-year-old male patient with first onset of severe major depression following cessation of daily excessive triptan use for 8 years. The depressive disorder was resistant to prior serotonergic antidepressant therapy. Antidepressant treatment with a non-serotonergic agent was successful in resolving depressive symptoms.

WHAT IS NEW AND CONCLUSION

The present case report demonstrates for the first time that acute cessation of long-term excessive triptan use has the potential to induce severe major depression, presumably due to persistent alterations in the serotonergic system including downregulation and desensitization of 5-HT(1) receptors. In this case, treatment with a non-serotonergic agent could be a promising therapeutic strategy.

Cerebrovascular disease and the elderly

A three-year follow-up study in Kassel (Federal Republic of Germany) has shown that (1) the incidence of stroke rises with increasing age, (2) the incidence is higher for men than for women, and (3) the survival rate is 37% three years after the attack. The survivors differ significantly from those who died in their Barthel index scores on discharge from hospital and in age (chi-square test). Only a small subgroup (15% of the survivors) received treatment in a residential rehabilitation centre in the year after discharge from hospital.

Mathematical modeling of regulatory mechanisms in yeast colony development

In the present study, yeast colony development serves as a model system to study growth of fungal populations with negligible nutrient and signal transport within the mycelium. Mathematical simulations address the question whether colony development is governed by diffusional limitation of nutrients. A hybrid one-dimensional cellular automaton model was developed that describes growth of discrete cells based upon microscopic interaction rules in a continuous field of nutrient and messenger. The model is scaled for the geometry of the experimental setup, cell size, growth- and substrate uptake rates. Therefore, calculated cell density profiles and nutrient distributions can be compared to experimental results and the model assumptions can be verified. In the physiologically relevant parameter range, simulations show an exponentially declining cell density along the median axis of the colonies in case of a diffusion limited growth scenario. These results are in good agreement with cell density profiles obtained in cultivations of the yeast Candida boidinii with glucose as the limiting carbon source but stand in contrast to the constant cell density profile estimated for Yarrowia lipolytica grown under the same conditions. While from the comparison of experimental results and simulations a diffusion limited growth mechanism is proposed for glucose limited C. boidinii colonies, this hypothesis is rejected for the growth of Y. lipolytica. As an alternative, a quorum sensing model was developed that can explain the evolution of constant cell density profiles based on the effect of a not further characterized unstable or volatile messenger.

Germ cell-less expression in medaka (Oryzias latipes)

The gene germ cell-less (gcl) plays an important role in the early differentiation of germ cells in Drosophila. We isolated the gcl homolog of the model teleost medaka (Oryzias latipes) using degenerated primers and an ovary cDNA bank. The predicted amino acid sequence of medaka gcl showed 92, 68 and 31% overall identity to mouse, human and Drosophila gcl respectively. RT-PCR revealed stronger expression in the ovary and weaker expression in testis, brain, heart, liver and muscle tissue. Expression in early embryos indicates the presence of maternal mRNA. By in situ hybridisation (ISH), gcl could not be detected in embryos. In contrast to vasa, ISH revealed expression of gcl in the ovary but not in the testis. Mol. Reprod. Dev. 67: 15-18, 2004.

Identification of functionally important regions of the Saccharomyces cerevisiae mitochondrial translational activator Cbs1p

Translation of cytochrome b mRNA in yeast mitochondria requires activation by the nuclear-encoded Cbs1p. According to the current model, Cbs1p tethers cytochrome b mRNA to the inner mitochondrial membrane via interaction with the 5'-untranslated leader. Cbs1p is predicted to be a hydrophilic protein with two hydrophobic segments near the carboxyl-terminal end, which are both too short to span the membrane. Nevertheless Cbs1p is tightly associated with the mitochondrial membrane, as shown by its behaviour in extraction experiments with taurodeoxycholate. In an attempt to define functionally important regions of Cbs1p, we created a number of mutant alleles by random and directed mutagenesis. We report that a Cbs1p mutant protein lacking the mitochondrial presequence is still able to complement a Deltacbs1 strain, suggesting that the presequence does not contain essential mitochondrial targeting information. Mutations in a cluster of positively charged amino acids at the extremeC-terminus have no effect on Cbs1p function, but removal of this segment severely impairs Cbs1p function. Truncation of 12 or more amino acids from the C-terminus results in a completely defective protein. We further show that both short hydrophobic regions are essential for Cbs1p function, although membrane association is observed even in the absence of these regions.

Human members of the SCO1 gene family: complementation analysis in yeast and intracellular localization

Cytochrome c oxidase is a multiprotein complex in the mitochondrial membrane whose biogenesis requires a number of proteins besides the structural subunits. Several yeast proteins as well as a human disease-related protein have been reported which are involved in cytochrome c oxidase assembly. The S. cerevisiae Sco1p protein has been implicated in the transfer of copper to cytochrome c oxidase subunits Cox1p and/or Cox2p. Here we report on the complementation behavior in yeast of two recently identified ScSco1p homologs of chromosome 17 and chromosome 22 from human. When allotropically expressed in yeast, both genes fail to complement the lack of the ScSCO1 gene. However, a chimera of the N-terminal half of ScSco1p and the C-terminal half of the chromosome 17 homolog does substitute for the ScSco1p function. Interestingly, the respective chimera with the human homolog of chromosome 22 is not able to complement. Expression of EGFP fusions in HeLa cells shows that both human ScSco1p homologs are located in the mitochondria of human cells.

Mitochondrial copper metabolism in yeast: mutational analysis of Sco1p involved in the biogenesis of cytochrome c oxidase

Saccharomyces cerevisiae Sco1p is believed to be involved in the transfer of copper from the carrier Cox17p to the mitochondrial cytochrome c oxidase subunits 1 and 2. We here report on the results of a mutational analysis of Sco1p. The two cysteine residues of a potential metal-binding motif (CxxxC) are essential for protein function as shown by their substitution by alanines. Chimeras consisting of Sco1p and its homolog S. cerevisiae Sco2p restrict the specificity of Sco1p function to the N-terminal half of the protein. A candidate region for conferring specificity on Sco1p is a stretch of hydrophobic amino acids, which act as a membrane anchor. In line with this suggestion is the result that alterations of individual amino acids within this region impair Sco1p function.

Homologous recombination in the fission yeast Schizosaccharomyces pombe: different requirements for the rhp51+, rhp54+ and rad22+ genes

The Schizosaccharomyces pombe rhp51+, rad22+ and rhp54+ genes are homologous to RAD51, RAD52 and RAD54 respectively, which are indispensable in the recombinational repair of double-strand breaks (DSBs) in Saccharomyces cerevisiae. The rhp51Delta and rhp54Delta strains are extremely sensitive to ionizing radiation; the rad22Delta mutant turned out to be much less sensitive. Homologous recombination in these mutants was studied by targeted integration at the leu1-32 locus. These experiments revealed that rhp51Delta and rhp54Delta are equally impaired in the integration of plasmid molecules (15-fold reduction), while integration in the rad22Delta mutant is only reduced by a factor of two. Blot-analysis demonstrated that the majority of the leu+ transformants of the wild-type and rad22Delta strains have integrated one or more copies of the vector. Gene conversion events were observed in less than 10% of the transformants. Interestingly, the relative contribution of gene conversion events is much higher in a rhp51Delta and a rhp54Delta background. Meiotic recombination is hardly affected in the rad22Delta mutant. The rhp51Delta and rhp54Delta strains also show minor deficiencies in this type of recombination. The viability of spores is 46% in the rad22Delta strain and 27% in the rhp54Delta strain, as compared with wild-type cells. However, in the rhp51Delta mutant the spore viability is only 1.7%, suggesting an essential role for Rhp51 in meiosis. The function of Rhp51 and Rhp54 in damage repair and recombination resembles the role of Rad51 and Rad54 in S. cerevisiae. Compared with Rad52 from S. cerevisiae, Rad22 has a much less prominent role in the recombinational repair pathway in S. pombe.

Cloning of human and mouse genes homologous to RAD52, a yeast gene involved in DNA repair and recombination

The RAD52 gene of Saccharomyces cerevisiae is required for recombinational repair of double-strand breaks. Using degenerate oligonucleotides based on conserved amino acid sequences of RAD52 and rad22, its counterpart from Schizosaccharomyces pombe, RAD52 homologs from man and mouse were cloned by the polymerase chain reaction. DNA sequence analysis revealed an open reading frame of 418 amino acids for the human RAD52 homolog and of 420 amino acid residues for the mouse counterpart. The identity between the two proteins is 69% and the overall similarity 80%. The homology of the mammalian proteins with their counterparts from yeast is primarily concentrated in the N-terminal region. Low amounts of RAD52 RNA were observed in adult mouse tissues. A relatively high level of gene expression was observed in testis and thymus, suggesting that the mammalian RAD52 protein, like its homolog from yeast, plays a role in recombination. The mouse RAD52 gene is located near the tip of chromosome 6 in region G3. The human equivalent maps to region p13.3 of chromosome 12. Until now, this human chromosome has not been implicated in any of the rodent mutants with a defect in the repair of double-strand breaks.

The mating-type region of Schizosaccharomyces pombe contains an essential gene encoding a protein homologous to human modulators of HIV transactivation

In Schizosaccharomyces pombe, an intrachromosomal crossover between the mating type (MT) expression locus and one of the silent donor cassettes is lethal due to the loss of the intervening L region. The region contains one essential gene, let1. This gene was cloned and sequenced. The deduced amino acid (aa) sequence of let1 shows extensive homologies with SUG1 from Saccharomyces cerevisiae. Significant homologies were also found with the human HIV transactivation modulators, MSS1 and TBP-1, as well as with subunit 4 of the mammalian 26 S protease. The data indicate that let1 is a member of a recently defined multigene family of ATPases.

Switching gene swi6, involved in repression of silent mating-type loci in fission yeast, encodes a homologue of chromatin-associated proteins from Drosophila and mammals

The switching gene swi6 of Schizosaccharomyces pombe is involved in the repression of the silent mating-type loci mat2 and mat3. We have cloned the gene by functional complementation of the switching defect of the swi6-115 mutation. DNA sequence analyses revealed an open reading frame of 984 bp coding for a putative protein of 328 amino acids (aa). The isolation of a swi6 cDNA confirmed this result. Gene replacement showed that swi6 is not essential for viability. The Swi6 protein is very hydrophilic; it contains 41% charged aa. A region of 48 aa is homologous to a sequence motif found in the chromatin-associated proteins, HP1 and Polycomb (Drosophila melanogaster), M31, M32 and M33 (mouse), and the human HSM1 protein. This motif is called chromo domain (chromatin organization modifier). Our results indicate that Swi6 is a structural component of chromatin. Swi6 may have the function to compact mat2 and mat3 into a heterochromatin-like conformation which represses the transcription of these silent cassettes.

Identification of a chicken RAD52 homologue suggests conservation of the RAD52 recombination pathway throughout the evolution of higher eukaryotes

Degenerate oligonucleotides encoding conserved regions of the Rad52 protein of S. cerevisiae and its homologue, the Rad22 protein of S. pombe, were used to clone a chicken RAD52 counterpart by the polymerase chain reaction. Sequence comparison of the chicken and yeast proteins reveals a strongly conserved region between positions 40 and 178 of the chicken Rad52 sequence indicating that this part of the protein is under strong evolutionary pressure. The first 39 amino acids and the 3' end of the chicken Rad52 homologue does not share significant similarity with the yeast proteins. High abundance of the mRNA in testis makes it likely that the chicken Rad52 protein plays a role in meiotic recombination.

The fission yeast rad22 gene, having a function in mating-type switching and repair of DNA damages, encodes a protein homolog to Rad52 of Saccharomyces cerevisiae

The gene rad22 of the fission yeast Schizosaccharomyces pombe has a function in DNA repair and mating-type switching. We have cloned the rad22 gene from a genomic gene bank by functional complementation of the switching defect. An open reading frame coding for a putative protein of 469 amino acids was found by sequence analyses. The rad22 gene contains no intron. A region of 126 amino acids in the N-terminal half of the Rad22 protein has significant homologies (56% identity and 36% similarity) to the Rad52 protein of Saccharomyces cerevisiae. A rad22 disruption strain was constructed which seems to be inviable in a homothallic background. Southern blot analyses have shown that the rad22-67 mutant frequently gives rise to deletions in the mating-type region. These data indicate that the Rad22 protein has a function in the repair of DNA double-strand breaks.

Analysis of DNA repair pathways of Schizosaccharomyces pombe by means of swi-rad double mutants

In Schizosaccharomyces pombe 11 different switching genes (swi1 to swi10 and rad22) are known which are involved in mating-type (MT) switching. Mutations in swi5, swi9, swi10 and rad22 also cause an increased radiation sensitivity. We tested whether the survival of these mutants after UV irradiation is influenced by caffeine. We included rad1 and rad13 mutants in our experiments which do not affect MT switching. Several double and triple mutants were constructed. We were able to assign the switching genes to different repair pathways: swi9 and swi10 are involved in excision repair, rad22 has a function in recombination repair, while swi5 appears to be involved in a hitherto unknown pathway. This 'swi5 pathway' is stimulated (!) by caffeine. Previously it was found that the swi5 mutation also reduces meiotic recombination. As to rad genes, we found a few inconsistencies with previous reports in the literature.