Self-Collected Oral Fluid and Nasal Swabs Demonstrate Comparable Sensitivity to Clinician Collected Nasopharyngeal Swabs for Coronavirus Disease 2019 Detection.

We compared self-collected oral fluid swab specimens with and without clinician supervision, clinician-supervised self-collected anterior nasal swab specimens, and clinician-collected nasopharyngeal swab specimens for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Supervised oral fluid and nasal swab specimens performed similarly to clinician-collected nasopharyngeal swab specimens. No sample type could detect SARS-CoV-2 infections amongst all positive participants.

A comparison of drug substance predicted chemical stability with ICH compliant stability studies.

OBJECTIVE: The aim of this study is to demonstrate the applicability of predictive stability studies to the degradation of drug substances. SIGNIFICANCE: The use of predicted stability studies during pharmaceutical development and in regulatory submissions is increasing, particularly in early phase to support an initial retest period/shelf life claim in the absence of standard stability data. These studies offer an alternative to standard stability testing and can facilitate clinical trials to be started earlier and medicines to reach patients faster. They involve a short-term stressed stability study, typically designed to degrade a drug substance or product to the specification level of the shelf life limiting attribute. The results are used to predict degradation under long-term storage conditions and enable stability understanding to be gained over a short time frame, using limited amounts of material. METHODS: In this work, Accelerated Stability Assessment Program (ASAP) studies were performed for 10 different drug substances and the predictions obtained for chemical degradation were compared to ICH compliant stability data. RESULTS: Across the studies good agreement was achieved, with the initial retest period predictions from the ASAP studies being conservative by design. When minimal degradation was observed during an ASAP study, it was demonstrated that at least a 12-month initial retest period could be supported. CONCLUSION: This comparison of ASAP predictions and ICH compliant stability data has demonstrated the ability of well-designed ASAP studies to predict the long-term chemical stability of drug substances.

[Cutaneous foreign body granulomas following cervico-facial arterial embolization: Three cases]. / Granulomes cutanés à corps étrangers après embolisation artérielle de la sphère cervico-faciale : trois cas.

BACKGROUND: Foreign body granuloma is an inflammatory tissue reaction to exogenous material. Classically it appears on the face after aesthetic procedures. Herein we report for the first time three cases of facial granulomatous reactions to microbeads after arterial cervico-facial embolization. PATIENTS AND METHODS: Three patients underwent embolization of the facial arteries using Embogold® microbeads in a setting of epistaxis or tumoral hemostasis. Within 10 to 45 days painful, inflammatory, subcutaneous nodules appeared on the homolateral side of the face. Histological samples showed an inflammatory response with giant cells as well as the presence of microbeads in the skin. A favorable outcome was achieved with colchicine in one patient and with surgery in another; the third patient was lost to follow-up. DISCUSSION: The embolizing microspheres produced a local inflammatory reaction, with destruction of the vascular wall and bead migration to facial tissue leading to a granulomatous reaction. The occurrence of three cases within a period of few weeks, with several different operators and batches of products, is surprising considering the long-standing use of the product. There was no common comorbidity in the patients and no suggestion of trauma. Retrospective analysis of the product batches was normal. Gold staining could play a role in severe inflammatory response to Embogold® particles. CONCLUSION: These three cases illustrate the value of discussing potential foreign body granulomatous reaction in cases of facial nodules following cervico-facial embolization. Colchicine may offer a valuable therapeutic alternative.

2-diethylaminoethyl-dextran methyl methacrylate copolymer nonviral vector: still a long way toward the safety of aerosol gene therapy.

Revealing the lung tumor genome has directed the current treatment strategies toward targeted therapy. First line treatments targeting the genome of lung tumor cells have been approved and are on the market. However, they are limited by the small number of patients with the current investigated genetic mutations. Novel treatment administration modalities have been also investigated in an effort to increase the local drug deposition and disease control. In the current study, we investigated the safety of the new nonviral vector 2-diethylaminoethyl-dextran methyl methacrylate copolymer (DDMC; Ryujyu Science), which belongs to the 2-diethylaminoethyl-dextran family by aerosol administration. Thirty male BALBC mice, 2 month old, were included and divided into three groups. However, pathological findings indicated severe emphysema within three aerosol sessions. In addition, the CytoViva technique was applied for the first time to display the nonviral particles within the pulmonary tissue and emphysema lesions, and a spectral library of the nonviral vector was also established. Although our results in BALBC mice prevented us from further investigation of the DDMC nonviral vector as a vehicle for gene therapy, further investigation in animals with larger airways is warranted to properly evaluate the safety of the vector.

Contingent interactions among biofilm-forming bacteria determine preservation or decay in the first steps toward fossilization of marine embryos.

Fossils of soft tissues provide important records of early animals and embryos, and there is substantial evidence for a role for microbes in soft tissue fossilization. We are investigating the initial events in interactions of bacteria with freshly dead tissue, using marine embryos as a model system. We previously found that microbial invasion can stabilize embryo tissue that would otherwise disintegrate in hours or days by generating a bacterial pseudomorph, a three dimensional biofilm that both replaces the tissue and replicates its morphology. In this study, we sampled seawater at different times and places near Sydney, Australia, and determined the range and frequency of different taphonomic outcomes. Although destruction was most common, bacteria in 35% of seawater samples yielded morphology­preserving biofilms. We could replicate the taphonomic pathways seen with seawater bacterial communities using single cultured strains of marine gammaproteobacteria. Each given species reproducibly generated a consistent taphonomic outcome and we identified species that yielded each of the distinct pathways produced by seawater bacterial communities. Once formed,bacterial pseudomorphs are stable for over a year and resist attack by other bacteria and destruction by proteases and other lytic enzymes. Competition studies showed that the initial action of a pseudomorphing strain can be blocked by a strain that destroys tissues. Thus embryo preservation in nature may depend on contingent interactions among bacterial species that determine if pseudomorphing occurs.We used Artemia nauplius larvae to show that bacterial biofilm replacement of tissue is not restricted to embryos, but is relevant for preservation of small multicellular organisms. We present a model for bacterial self­assembly of large­scale three­dimensional tissue pseudomorphs, based on smallscaleinteractions among individual bacterial cells to form local biofilms at structural boundaries within the tissue. Localbiofilms then conjoin to generate the pseudomorph.

Experimental taphonomy of giant sulphur bacteria: implications for the interpretation of the embryo-like Ediacaran Doushantuo fossils.

The Ediacaran Doushantuo biota has yielded fossils interpreted as eukaryotic organisms, either animal embryos or eukaryotes basal or distantly related to Metazoa. However, the fossils have been interpreted alternatively as giant sulphur bacteria similar to the extant Thiomargarita. To test this hypothesis, living and decayed Thiomargarita were compared with Doushantuo fossils and experimental taphonomic pathways were compared with modern embryos. In the fossils, as in eukaryotic cells, subcellular structures are distributed throughout cell volume; in Thiomargarita, a central vacuole encompasses approximately 98 per cent cell volume. Key features of the fossils, including putative lipid vesicles and nuclei, complex envelope ornament, and ornate outer vesicles are incompatible with living and decay morphologies observed in Thiomargarita. Microbial taphonomy of Thiomargarita also differed from that of embryos. Embryo tissues can be consumed and replaced by bacteria, forming a replica composed of a three-dimensional biofilm, a stable fabric for potential fossilization. Vacuolated Thiomargarita cells collapse easily and do not provide an internal substrate for bacteria. The findings do not support the hypothesis that giant sulphur bacteria are an appropriate interpretative model for the embryo-like Doushantuo fossils. However, sulphur bacteria may have mediated fossil mineralization and may provide a potential bacterial analogue for other macroscopic Precambrian remains.

[Mucoepidermoid carcinomas of salivary glands: prognostic significance of immunohistochemistry. A study of 49 cases]. / Carcinomes muco-épidermoïdes des glandes salivaires : valeur pronostique de l'immuno-histochimie. A propos de 49 cas.

INTRODUCTION: Mucoepidermoid carcinoma (MEC) is considered as the most common malignant salivary gland tumor. Its prognosis is dominated by the presence of high-grade forms involving life-threatening. The aim of our study was to evaluate the usefulness of immunohistochemistry to identify the most aggressive forms and allow better discrimination between low grade, intermediate grade and high grade tumors. MATERIALS AND METHODS: This was a retrospective study of 49 cases of mucoepidermoid carcinomas of salivary glands. Two immunohistochemical markers have mainly been studied: a marker of proliferation (Ki-67) and a growth factor receptor (EGFR). Additional analyzes were performed with other markers (p53, ACE, bcl2, CD 117 and her2). Statistical analysis investigated the existence of a correlation between the presence of these factors and the histopathological grade on one hand and survival of patients on the other hand. RESULTS: Regarding the results of immunohistochemical Ki-67 and EGFR, it was observed a better survival rate when the immunostaining was less than 10%. The expression of Ki-67 and EGFR was correlated with the histological grade, but did not, in our study, allow discrimination between low-grade, intermediate grade and high grade. Our results are consistent with data of the literature, including Ki-67, which appears to be a useful but not powerful marker of prognosis of MEC. Other markers studied (p53, ACE, bcl2, CD 117 and her2) showed no contributory results. CONCLUSION: The prognosis of MEC is appreciated satisfactorily following histological criteria: histological grade, surgical margins, perineural invasion or vascular emboli. The integration of immunohistochemistry in a therapeutic algorithm could be particularly useful for the challenging assessment of prognosis of intermediate grades.

Axoneme beta-tubulin sequence determines attachment of outer dynein arms.

Axonemes of motile eukaryotic cilia and flagella have a conserved structure of nine doublet microtubules surrounding a central pair of microtubules. Outer and inner dynein arms on the doublets mediate axoneme motility [1]. Outer dynein arms (ODAs) attach to the doublets at specific interfaces [2-5]. However, the molecular contacts of ODA-associated proteins with tubulins of the doublet microtubules are not known. We report here that attachment of ODAs requires glycine 56 in the beta-tubulin internal variable region (IVR). We show that in Drosophila spermatogenesis, a single amino acid change at this position results in sperm axonemes markedly deficient in ODAs. Moreover, we found that axonemal beta-tubulins throughout the phylogeny have invariant glycine 56 and a strongly conserved IVR, whereas nonaxonemal beta-tubulins vary widely in IVR sequences. Our data reveal a deeply conserved physical requirement for assembly of the macromolecular architecture of the motile axoneme. Amino acid 56 projects into the microtubule lumen [6]. Imaging studies of axonemes indicate that several proteins may interact with the doublet-microtubule lumen [3, 4, 7, 8]. This region of beta-tubulin may determine the conformation necessary for correct attachment of ODAs, or there may be sequence-specific interaction between beta-tubulin and a protein involved in ODA attachment or stabilization.

Embryo fossilization is a biological process mediated by microbial biofilms.

Fossilized embryos with extraordinary cellular preservation appear in the Late Neoproterozoic and Cambrian, coincident with the appearance of animal body fossils. It has been hypothesized that microbial processes are responsible for preservation and mineralization of organic tissues. However, the actions of microbes in preservation of embryos have not been demonstrated experimentally. Here, we show that bacterial biofilms assemble rapidly in dead marine embryos and form remarkable pseudomorphs in which the bacterial biofilm replaces and exquisitely models details of cellular organization and structure. The experimental model was the decay of cleavage stage embryos similar in size and morphology to fossil embryos. The data show that embryo preservation takes place in 3 distinct steps: (i) blockage of autolysis by reducing or anaerobic conditions, (ii) rapid formation of microbial biofilms that consume the embryo but form a replica that retains cell organization and morphology, and (iii) bacterially catalyzed mineralization. Major bacterial taxa in embryo decay biofilms were identified by using 16S rDNA sequencing. Decay processes were similar in different taphonomic conditions, but the composition of bacterial populations depended on specific conditions. Experimental taphonomy generates preservation states similar to those in fossil embryos. The data show how fossilization of soft tissues in sediments can be mediated by bacterial replacement and mineralization, providing a foundation for experimentally creating biofilms from defined microbial species to model fossilization as a biological process.

Direct test of laser tunneling with electron momentum imaging.

Tunneling is often used to describe multiphoton ionization of rare gas atoms in infrared fields. We test the tunneling approximation and its nonadiabatic extension by measuring the unperturbed momentum distribution along the κ direction of a circularly polarized light pulse. We find substantial, but not total, agreement between our results and the predictions of the model. As predicted, the κ direction momentum distribution is Gaussian and its width increases with the square root of electric field strength. However, the width is 15% too large and we find no evidence of nonadiabatic effects as we approach the expected limits of the approximation.

Axial patterning of the pentaradial adult echinoderm body plan.

Adult echinoderms possess a highly diverged, pentaradial body plan. Developmental mechanisms underlying this body plan are completely unknown, but are critical in understanding how echinoderm pentamery evolved from bilateral ancestors. These mechanisms are difficult to study in indirect-developing species; in this study, we use the direct-developing sea urchin Heliocidaris erythrogramma, whose accelerated adult development can be perturbed by NiCl(2). We introduce a new nomenclature for the adult echinoderm axes to facilitate discussion of the radially symmetric body plan and the events required to pattern it. In sea urchins, the adult oral-aboral axis is often conflated with the long axes of the five rays; we identify these as distinct body axes, the proximodistal (PD). In addition, we define a circular axis, the circumoral (CO), along which the division into five sectors occurs. In NiCl(2)-treated larvae, aspects of normal PD pattern were retained, but CO pattern was abolished. Milder treatments resulted in relatively normal juveniles ranging from biradial to decaradial. NiCl(2) treatment had no effect either on mesodermal morphology or on the ectodermal gene expression response to an inductive mesodermal signal. This suggests that the mesoderm does not mediate the disruption of CO patterning by NiCl(2). In contrast, mesodermal signaling may explain the presence of PD pattern in treated larvae. However, variations in appendage pattern suggest that ectodermal signals are also required. We conclude that CO patterning in both germ layers is dependent on ectodermal events and PD patterning is controlled by mutual ectoderm-mesoderm signaling.

Cytochrome P450 2B6 516G-->T is associated with plasma concentrations of nevirapine at both 200 mg twice daily and 400 mg once daily in an ethnically diverse population.

OBJECTIVES: The aim of the study was to characterize the impact of the cytochrome P450 2B6 (CYP2B6), CYP3A4, CYP3A5 and ATP-binding cassette sub-family B member 1 (ABCB1) polymorphisms on nevirapine plasma concentrations. METHODS: A total of 104 patients (82% male; 26% non-Caucasian) were genotyped for eight single nucleotide polymorphisms at four loci (CYP2B6, CYP3A4, CYP3A5 and MDR1). Nevirapine plasma concentrations were determined using high-performance liquid chromatography. RESULTS: Non-Caucasian ethnicity [5609 ng/mL (n=27) for non-Caucasians vs. 3771 ng/mL (n=77) for Caucasians; P<0.0001] and CYP2B6 516G-->T [GG, 3574 ng/mL (n=50); GT, 4634 ng/mL (n=50); TT, 8170 ng/mL (n=4); P(analysis of variance (anova))=0.001] were significantly associated with a higher nevirapine trough concentration (C(trough)). The latter association was maintained with both 200 mg twice daily (bid) and 400 mg once daily (qd) dosing [GG, 3527 ng/mL (n=30); GT, 4525 ng/mL (n=32); TT, 7020 ng/mL (n=2); P(anova)=0.05 and GG, 3645 ng/mL (n=20); GT, 4861 ng/mL (n=17); TT, 9508 ng/mL (n=2); P(anova)=0.01, respectively]. In a multivariable analysis, CYP2B6 516G-->T and non-Caucasian ethnicity remained significant predictors of nevirapine C(trough) but CYP2B6 516G-->T homozygosity had the greatest effect (108% higher, 46% higher). No associations were found between nevirapine C(trough) and the remaining polymorphisms. CONCLUSION: In this population, both non-Caucasian ethnicity and carriage of the variant allele of CYP2B6 516G-->T were significant predictors of nevirapine C(trough). The association between CYP2B6 516G-->T and higher plasma nevirapine exposure was maintained at both bid and qd dosing.

An ultrastructural study of plant spermatogenesis. Spermatogenesis in Nitella.

Spermatogenesis in the charophyte Nitella has been followed in antheridia prepared for light and electron microscopy. The antheridial filament cells contain paired centrioles which are similar in structure and behavior to the centrioles of animal cells. In the early spermatid, the centrioles undergo an initial elongation at their distal ends and become joined by a spindle-shaped fibrous connection. At the same time, their proximal ends are closely associated with the development of a layer of juxtaposed microtubules which will form the microtubular sheath. The architectural arrangement of these microtubules suggests that they constitute a cytoskeletal system, forming a framework along which the mitochondria and plastids become aligned and along which the nucleus undergoes extensive elongation and differentiation. The microtubular sheath persists in the mature sperm. During mid-spermatid stages, the centrioles give rise to the flagella and concomitantly undergo differentiation to become the basal bodies. The Golgi apparatus goes through a period of intensive activity during mid-spermatid stages, then decreases in organization until it can no longer be detected in the late spermatid. An attempt is made to compare similarities between plant and animal spermiogenesis.

The effects of colchicine on spermatogenesis in Nitella.

Treatment of Nitella antheridia with colchicine results in various sperm abnormalities, depending upon duration of exposure and subsequent recovery. Early effects of treatment include disappearance of spindle fibers and a cessation of ordered cell wall formation in dividing cells. Sperm released from antheridia treated for 24 hr and allowed to recover for 4-5 days possess branched flagella. After a recovery period of 6-10 days the sperm appear normal; however, following longer recovery periods, the sperm exhibit variations in size and number of flagella. Branched flagella contain a variety of microtubule patterns ranging from branches containing a single microtubule to flagella with an excess of microtubules. Spermatids which differentiate in the presence of colchicine lack flagella and a microtubular sheath. Nuclear contents undergo condensation stages; however, the nucleus as a whole does not undergo the orderly elongation and coiling characteristic of untreated Nitella spermatids. Long-term colchicine treatment followed by a recovery period produces atypical microtubules and microtubular aggregations in the spermatid. The results indicate that colchicine affects not only polymerization of microtubule subunits but also factors responsible for their ordered spatial relationships in the cell. The presence of microtubules is a prerequisite for normal morphological changes during spermiogenesis.

Interspecific transplantation of polar plasm between Drosophila embryos.

Posterior polar plasm of the Drosophila egg has been shown to function autonomously in germ cell determination after transplantation to either the anterior or mid-ventral region of the early embryo. By means of similar transplantations, we have tested the ability of polar plasm of Drosophila immigrans to induce the formation of pole cells in a Drosophila melanogaster embryo. After the transplantation of polar plasm, "hybrid" pole cells were found in which both pole cell-specific organelles, the polar granules and nuclear body, were structurally similar to those characteristic of the transplanted cytoplasm. In order to determine whether these hybrid cells can function as germ cell precursors, these cells were transplanted to the posterior tip of genetically marked embryos. Approximately 5% of the flies obtained from embryos receiving potential pole cells produce offspring derived from the induced pole cells. This result demonstrates that polar plasm can function in interspecific species combinations and indicates that the molecular mechanisms of germ cell determination are conservative in evolution. Finally, in order to test whether there is any evidence for cytoplasmic inheritance of polar granules, embryos derived from hybrid pole cells were examined for their polar granule morphology. The fine structure of the granules conformed to that of the nucleus. Thus, no evidence was found for the cytoplasmic inheritance of these particular organelles.

Drosophila centrosomin protein is required for male meiosis and assembly of the flagellar axoneme.

Centrosomes and microtubules play crucial roles during cell division and differentiation. Spermatogenesis is a useful system for studying centrosomal function since it involves both mitosis and meiosis, and also transformation of the centriole into the sperm basal body. Centrosomin is a protein localized to the mitotic centrosomes in Drosophila melanogaster. We have found a novel isoform of centrosomin expressed during spermatogenesis. Additionally, an anticentrosomin antibody labels both the mitotic and meiotic centrosomes as well as the basal body. Mutational analysis shows that centrosomin is required for spindle organization during meiosis and for organization of the sperm axoneme. These results suggest that centrosomin is a necessary component of the meiotic centrosomes and the spermatid basal body.

Microtubule architecture specified by a beta-tubulin isoform.

In Drosophila melanogaster, a testis-specific beta-tubulin (beta2) is required for spermatogenesis. A sequence motif was identified in carboxyl termini of axonemal beta-tubulins in diverse taxa. As a test of whether orthologous beta-tubulins from different species are functionally equivalent, the moth Heliothis virescens beta2 homolog was expressed in Drosophila testes. When coexpressed with beta2, the moth isoform imposed the 16-protofilament structure characteristic of that found in the moth on the corresponding subset of Drosophila microtubules, which normally contain only 13-protofilament microtubules. Thus, the architecture of the microtubule cytoskeleton can be directed by a component beta-tubulin.

A schwannoma of the hypoglossal nerve presenting as a malignant tumour of the oral floor.

OBJECTIVES: We describe a case of an unusual schwannoma of the hypoglossal nerve presenting clinically as a malignant tumour of the floor of the oral cavity. CASE REPORT: A 77-year-old woman presented with a bulky tumour located between the left anterior floor of mouth and the ventricular portion of the tongue. The tumour was ulcerated, painful and presented with a necrotic aspect. Neurological examination revealed a mild left hemiparesis of the tongue. MRI and CT showed a circumscribed tumour with a broad necrotic centre. The patient underwent a transoral excision of the tumour under general anaesthesia. CONCLUSION: Schwannomas are generally managed by complete surgical excision but they can mimic primary or metastatic cancer in the head and neck, preoperative diagnosis is therefore necessary to avoid a wide excision.

Cooperativity between the beta-tubulin carboxy tail and the body of the molecule is required for microtubule function.

Using Drosophila spermatogenesis as a model, we show that function of the beta-tubulin C-terminal tail (CTT) is not independent of the body of the molecule. For optimal microtubule function, the beta-tubulin CTT and body must match. beta2 is the only beta-tubulin used in meiosis and spermatid differentiation. beta1-tubulin is used in basal bodies, but beta1 cannot replace beta2. However, when beta1 is co-expressed with beta2, both beta-tubulins are equally incorporated into all microtubules, and males exhibit near wild type fertility. In contrast, co-expression of beta2beta1C and beta1beta2C, two reciprocal chimeric molecules with bodies and tails swapped, results in defects in meiosis, cytoskeletal microtubules, and axonemes; males produce few functional sperm and few or no progeny. In these experiments, all the same beta-tubulin parts are present, but unlike the co-assembled native beta-tubulins, the "trans" configuration of the co-assembled chimeras is poorly functional. Our data thus reveal essential intra-molecular interactions between the CTT and other parts of the beta-tubulin molecule, even though the CTT is a flexible surface feature of tubulin heterodimers and microtubules. In addition, we show that Drosophila sperm tail length depends on the total tubulin pool available for axoneme assembly and spermatid elongation. D. melanogaster and other Drosophila species have extraordinarily long sperm tails, the length of which is remarkably constant in wild type flies. We show that in males of experimental genotypes that express wild type tubulins but have half the amount of the normal tubulin pool size, sperm tails are substantially shorter than wild type.

Nodal expression and heterochrony in the evolution of dorsal-ventral and left-right axes formation in the direct-developing sea urchin Heliocidaris erythrogramma.

To understand the role of body axes in the evolution of larval form, we use the two sea urchins in the genus Heliocidaris, which have distinctly different larval morphologies. Heliocidaris tuberculata is an indirect-developing sea urchin, which forms a pluteus larva, whereas its sister species, Heliocidaris erythrogramma, exhibits direct development and forms a nonfeeding, ovoid larva. Changes along all three larval axes underlie the differences in larval form associated with each developmental mode. Nodal signaling has recently been implicated as important in establishing the dorsal-ventral (D-V) and left-right (L-R) axes in the indirect-developing sea urchin Paracentrotus lividus. However, because of changes in morphology and timing of morphogenetic events associated with the D-V and L-R axes, respectively, in H. erythrogramma, it was unclear whether nodal played the same roles during direct development. We show that the expression patterns and functions of nodal during H. erythrogramma development are similar to its roles in indirect-developing sea urchins in both D-V and L-R axes formation. However, there are profound changes in gene expression downstream of nodal signaling along the D-V axis and major heterochronies in the execution of the function of nodal along the L-R axis. These highly modified events are linked to the dramatic modifications of larval morphology that have occurred during the evolution of direct development in H. erythrogramma.