Detection of fungi in the airways of horses according to the sample site: a methodological study.

Fungal detection in equine airways may be performed on either tracheal wash (TW) or bronchoalveolar lavage fluid (BALF) by either cytology or culture. However, method comparisons are sparse. Our objective was to determine the prevalence of fungi in airways of horses according to the sample site and laboratory methodology. Sixty-two adult horses, investigated in the field or referred for respiratory disease, were included. Tracheal wash, and BALF collected separately from both lungs, were collected using a videoendoscope. Fungi were detected in cytologic samples examined by light microscopy, and by fungal culture. Hay was sampled in the field. Prevalence of fungi was of 91.9% in TW and 37.1% in BALF. Fungi were cultured from 82.3% of TW and 20.9% of BALF. Fungal elements were observed cytologically in 69.4% of TW and 22.6% of BALF. In 50% of horses, the same fungi were detected in both TW and hay, but fungi detected in BALF and hay differed in all horses. Poor agreement was found for the detection of fungi between TW and BALF and between fungal culture and cytologic examination (Cohen's kappa coefficient (κ) < 0.20). Moderate agreement was found between cytologic examination of left and right lungs (κ = 0.47). The prevalence of fungi detected cytologically on pooled BALF was significantly different (p = 0.023) than on combined left and right BALF. Fungi were more prevalent in the TW than BALF, and results suggest that hay might not be the primary source of fungi of the lower respiratory tract of horses.

High-flow cannula for frail patients with SARS-CoV-2 infection non-eligible for intensive care unit management.

OBJECTIVES: High-flow nasal cannula (HFNC) was widely used during the COVID-19 pandemic in intensive care units (ICU), but there is no recommendation for elderly patients non-eligible for ICU management. We aimed to describe the outcomes of HFNC treatment in patients with COVID-19 who are not eligible for ICU management. METHODS: Retrospective bicentric cohort study performed between September 1, 2020 and June 30, 2021 in two infectious diseases departments of Colmar Hospital and Antoine Beclere University Hospital, France. RESULTS: Sixty-four patients were treated with HFNC: 33 in Colmar and 31 in Beclere hospital (median age: 85 years; IQ, 82-92). Of these, 16 patients survived (25%). Surviving patients had a lower Charlson comorbidity index score than deceased patients (five vs six; p = 0.02). CONCLUSIONS: Despite a high death rate, with survivors being younger and having fewer comorbidities, HFNC is an easy tool to implement in non-ICU wards for the frailest patients.

The multi-faceted nature of 15 CFTR exonic variations: Impact on their functional classification and perspectives for therapy.

BACKGROUND: The majority of variants of unknown clinical significance (VUCS) in the CFTR gene are missense variants. While change on the CFTR protein structure or function is often suspected, impact on splicing may be neglected. Such undetected splicing default of variants may complicate the interpretation of genetic analyses and the use of an appropriate pharmacotherapy. METHODS: We selected 15 variants suspected to impact CFTR splicing after in silico predictions on 319 missense variants (214 VUCS), reported in the CFTR-France database. Six specialized laboratories assessed the impact of nucleotide substitutions on splicing (minigenes), mRNA expression levels (quantitative PCR), synthesis and maturation (western blot), cellular localization (immunofluorescence) and channel function (patch clamp) of the CFTR protein. We also studied maturation and function of the truncated protein, consecutive to in-frame aberrant splicing, on additional plasmid constructs. RESULTS: Six of the 15 variants had a major impact on CFTR splicing by in-frame (n = 3) or out-of-frame (n = 3) exon skipping. We reclassified variants into: splicing variants; variants causing a splicing defect and the impairment of CFTR folding and/or function related to the amino acid substitution; deleterious missense variants that impair CFTR folding and/or function; and variants with no consequence on the different processes tested. CONCLUSION: The 15 variants have been reclassified by our comprehensive approach of in vitro experiments that should be used to properly interpret very rare exonic variants of the CFTR gene. Targeted therapies may thus be adapted to the molecular defects regarding the results of laboratory experiments.

Comparison of analog and digitally evaluated volume of the female breast in reconstructive breast surgery. Validation of a noninvasive measurement method with 3D camera1.

BACKGROUND: Reconstructive surgery is established as a standard treatment option after mastectomy due to cancer. It is crucial to patients to achieve a natural and symmetric looking breast through reconstruction. Anthropometric measurements are used to assess the objective symmetry of the breast, which are prone to errors and difficult to reproduce. OBJECTIVE: The aim of this work is to validate breast volumetry using three-dimensional surface imaging. METHODS: We compared preoperatively analog and digitally evaluated volume of the breast with our gold standard, direct water displacement measurement of the mastectomy specimen. We examined 34 breast specimens in total. RESULTS: Each measurement method (Breast Sculptor, VAM, Breast-V) for breast volume/mass determination demonstrates acceptable agreement ranges when compared with resected volumes and masses. The strongest volumetry instrument is Breast Sculptor (digital), the weakest is Breast-V (analog). CONCLUSIONS: 3D surface imaging is a quick, effective, and convenient method to evaluate breast shape and volume. The accuracy, reproducibility, and reliability of 3D surface imaging were comparable with MRI in our study.This takes us a step closer to the long-term goal of establishing robust instruments to plan breast reconstructive surgery, achieve better surgical results, and contribute to quality assurance in breast surgery.

PSA reduces prostate cancer cell motility by stimulating TRPM8 activity and plasma membrane expression.

Although the transient receptor potential melastatin 8 (TRPM8) cold receptor is highly expressed in prostate cancer (PCa) and constitutes a promising diagnostic and prognostic indicator, the natural agonists of this channel in the prostate, as well as its physiological and pathological functions, remain unknown. In this study, we identified the well-known PCa marker, prostate-specific antigen (PSA), as a physiological TRPM8 agonist. Electrophysiological and Ca(2+) imaging studies demonstrated that PSA activated TRPM8-mediated current by the bradykinin 2 receptor signaling pathway. Further investigation of this mechanism by cell-surface biotinylation revealed that the increase in TRPM8 current induced by PSA was due to an increase in the number of functional TRPM8 channels on the plasma membrane. Importantly, wound-healing and migration assays revealed that TRPM8 activation by PSA reduced motility of the PC3 PCa cell line, suggesting that plasma membrane TRPM8 has a protective role in PCa progression. Consequently, PSA was identified as a natural TRPM8 agonist in the prostate and we propose a putative physiological role for both of these proteins in carcinogenesis, making this pathway a potentially important target for anticancer agent development.

Phospholipase C-coupled receptors and activation of TRPC channels.

The canonical transient receptor potential (TRPC) cation channels are mammalian homologs of the photoreceptor channel TRP in Drosophila melanogaster. All seven TRPCs (TRPC1 through TRPC7) can be activated through Gq/11 receptors or receptor tyrosine kinase (RTK) by mechanisms downstream of phospholipase C. The last decade saw a rapidly growing interest in understanding the role of TRPC channels in calcium entry pathways as well as in understanding the signal(s) responsible for TRPC activation. TRPC channels have been proposed to be activated by a variety of signals including store depletion, membrane lipids, and vesicular insertion into the plasma membrane. Here we discuss recent developments in the mode of activation as well as the pharmacological and electrophysiological properties of this important and ubiquitous family of cation channels.

Pituitary adenylyl cyclase-activating polypeptide (PACAP) and its receptor (PAC1-R) are positioned to modulate afferent signaling in the cochlea.

Pituitary adenylyl cyclase-activating polypeptide (PACAP), via its specific receptor pituitary adenylyl cyclase-activating polypeptide receptor 1 (PAC1-R), is known to have roles in neuromodulation and neuroprotection associated with glutamatergic and cholinergic neurotransmission, which, respectively, are believed to form the primary basis for afferent and efferent signaling in the organ of Corti. Previously, we identified transcripts for PACAP preprotein and multiple splice variants of its receptor, PAC1-R, in microdissected cochlear subfractions. In the present work, neural localizations of PACAP and PAC1-R within the organ of Corti and spiral ganglion were examined, defining sites of PACAP action. Immunolocalization of PACAP and PAC1-R in the organ of Corti and spiral ganglion was compared with immunolocalization of choline acetyltransferase (ChAT) and synaptophysin as efferent neuronal markers, and glutamate receptor 2/3 (GluR2/3) and neurofilament 200 as afferent neuronal markers, for each of the three cochlear turns. Brightfield microscopy giving morphological detail for individual immunolocalizations was followed by immunofluorescence detection of co-localizations. PACAP was found to be co-localized with ChAT in nerve fibers of the intraganglionic spiral bundle and beneath the inner and outer hair cells within the organ of Corti. Further, evidence was obtained that PACAP is expressed in type I afferent axons leaving the spiral ganglion en route to the auditory nerve, potentially serving as a neuromodulator in axonal terminals. In contrast to the efferent localization of PACAP within the organ of Corti, PAC1-R immunoreactivity was co-localized with afferent dendritic neuronal marker GluR2/3 in nerve fibers passing beneath and lateral to the inner hair cell and in fibers at supranuclear and basal sites on outer hair cells. Given the known association of PACAP with catecholaminergic neurotransmission in sympathoadrenal function, we also re-examined the issue of whether the organ of Corti receives adrenergic innervation. We now demonstrate the existence of nerve fibers within the organ of Corti which are immunoreactive for the adrenergic marker dopamine beta-hydroxylase (DBH). DBH immunoreactivity was particularly prominent in nerve fibers both at the base and near the cuticular plate of outer hair cells of the apical turn, extending to the non-sensory Hensen's cell region. Evidence was obtained for limited co-localization of DBH with PAC1-R and PACAP. In the process of this investigation, we obtained evidence that efferent and afferent nerve fibers, in addition to adrenergic nerve fibers, are present at supranuclear sites on outer hair cells and distributed within the non-sensory epithelium of the apical cochlear turn for rat, based upon immunoreactivity for the corresponding neuronal markers. Overall, PACAP is hypothesized to act within the organ of Corti as an efferent neuromodulator of afferent signaling via PAC1-R that is present on type I afferent dendrites, in position to afford protection from excitotoxicity. Additionally, PACAP/PAC1-R may modulate secretion of catecholamines from adrenergic terminals within the organ of Corti.

Alterations in the regulatory volume decrease (RVD) and swelling-activated Cl- current associated with neuroendocrine differentiation of prostate cancer epithelial cells.

Neuroendocrine (NE) differentiation of prostate epithelial/basal cells is a hallmark of advanced, androgen-independent prostate cancer, for which there is no successful therapy. Here we report for the first time on alterations in regulatory volume decrease (RVD) and its key determinant, swelling-activated Cl- current (I(Cl,swell)), associated with NE differentiation of androgen-dependent LNCaP prostate cancer epithelial cells. NE-differentiating regimens, namely, chronic cAMP elevation or androgen deprivation, resulted in generally augmented I(Cl,swell) and enhanced RVD. This occurred as a result of both the increased endogenous expression of ClC-3, which is a volume-sensitive Cl- channel involved, as we show, in I(Cl,swell) in LNCaP (lymph-node carcinoma of the prostate) cells and the weaker negative I(Cl,swell) control from Ca2+ entering via store-dependent pathways. The changes in the RVD of NE-differentiated cells generally mimicked those reported for Bcl-2-conferred apoptotic resistance. Our results suggest that strengthening the mechanism that helps to maintain volume constancy may contribute to better survival rates of apoptosis-resistant NE cells.

2-APB inhibits volume-regulated anion channels independently from intracellular calcium signaling modulation.

It has previously been suggested that volume-regulated anion channels (VRACs) and store-operated channels (SOCs) interact with each other according to their expected colocalization in the plasma membrane of LNCaP cells. In order to study interactions between these two channels, we used 2-aminoethoxydiphenyl borate (2-APB) as a regular SOC inhibitor. Surprisingly 2-APB reduced VRAC activity in a dose-dependent manner (IC(50)=122.8 microM), but not 2,2-diphenyltetrahydrofuran (a structural analog of 2-APB). This effect was also present in keratinocytes. We conclude that 2-APB is an inhibitor of the VRAC family, and is also a potent tool to study the SOC-VRAC interaction in LNCaP cells.

Store-operated Ca2+ channels in prostate cancer epithelial cells: function, regulation, and role in carcinogenesis.

Ca2+ homeostasis mechanisms, in which the Ca2+ entry pathways play a key role, are critically involved in both normal function and cancerous transformation of prostate epithelial cells. Here, using the lymph node carcinoma of the prostate (LNCaP) cell line as a major experimental model, we characterize prostate-specific store-operated Ca2+ channels (SOCs)--a primary Ca2+ entry pathway for non-excitable cells--for the first time. We show that prostate-specific SOCs share major store-dependent, kinetic, permeation, inwardly rectifying, and pharmacological (including dual, potentiation/inhibition concentration-dependent sensitivity to 2-APB) properties with "classical" Ca2+ release-activated Ca2+ channels (CRAC), but have a higher single channel conductance (3.2 and 12pS in Ca2+- and Na+-permeable modes, respectively). They are subject to feedback inhibition via Ca2+-dependent PKC, CaMK-II and CaM regulatory pathways and are functionally dependent on caveolae integrity. Caveolae also provide a scaffold for spatial co-localization of SOCs with volume-regulated anion channels (VRAC) and their Ca2+-mediated interaction. The TRPC1 and TRPV6 members of the transient receptor potential (TRP) channel family are the most likely molecular candidates for the formation of prostate-specific endogenous SOCs. Differentiation of LNCaP cells to an androgen-insensitive, apoptotic-resistant neuroendocrine phenotype downregulates SOC current. We conclude that prostate-specific SOCs are important determinants in the transition to androgen-independent prostate cancer.

A new human gene KCNRG encoding potassium channel regulating protein is a cancer suppressor gene candidate located in 13q14.3.

We report the primary characterization of a new gene KCNRG mapped at chromosome band 13q14.3. This gene includes three exons and has two alternatively spliced isoforms that are expressed in normal tissues and in some tumor cell lines. Protein KCNRG has high homology to tetramerization domain of voltage-gated K+ channels. Using the patch-clamp technique we determined that KCNRG suppresses K+ channel activity in human prostate cell line LNCaP. It is known that selective blockers of K+ channels suppress lymphocyte and LNCaP cell line proliferation. We suggest that KCNRG is a candidate for a B-cell chronic lymphocytic leukemia and prostate cancer tumor suppressor gene.

Direct modulation of volume-regulated anion channels by Ca(2+) chelating agents.

Ca(2+) chelating agents are widely used in biological research for Ca(2+) buffering. Here we report that BAPTA, EDTA and HEDTA produce fast, reversible, voltage-dependent inhibition of swelling-activated Cl(-) current (I(Cl,swell)) in LNCaP prostate cancer epithelial cells that is unrelated to their Ca(2+) binding. BAPTA was the most effective (maximal blockade 67%, IC(50)=70 microM, at +100 mV) followed by EDTA and HEDTA. I(Cl,swell) blockade by EDTA was pH-dependent. BAPTA blocked I(Cl,swell) also in other cell types. We conclude that Ca(2+) chelating agents block I(Cl,swell) by acting directly on the underlying channel, and that the negative charge of the free chelator form is critical for the blockade.

Genotypic drug resistance and cause of death in HIV-infected persons who died in 1999.

We analyzed the relationship between viral drug resistance and causes of death in 29 HIV-1-infected patients who had been followed in an HIV-outpatient clinic and died in 1999. Six patients (21%) died with plasma HIV-RNA levels <1000 copies/ml. Seven (24%) died with wild-type (WT) virus in plasma, 6 (21%) had reverse transcriptase (RT) mutations only, 10 (34%) had multidrug-resistant (MDR) virus. The causes of death were not differently distributed among these groups; however, 8 of 16 patients (50%) with resistant viruses died of end-organ failure versus 2 of 7 patients (29%) with WT virus. Seventeen of 32 patients (53%) were thought by their physicians to be noncompliant with prescribed therapy. Major resistance mutations to antiretroviral drugs were present in viruses from at least 55% of our HIV-1-infected patients who died in 1999. Nonetheless, deaths also occurred among patients with well-controlled HIV infection and among patients with WT virus in plasma. Infections related to incomplete immune restoration, inability to maintain suppressive antiretroviral drug levels, and end-organ failures all contribute to mortalities in the era of highly active antiretroviral therapy.

Modulation of intracellular beta-catenin localization and intestinal tumorigenesis in vivo and in vitro by sphingolipids.

Sphingolipid consumption suppresses colon carcinogenesis, but the specific genetic defect(s) that can be bypassed by these dietary components are not known. Colon tumors often have defect(s) in the adenomatous polyposis coli (APC)/beta-catenin regulatory system. Therefore, C57Bl/6J(Min/+) mice with a truncated APC gene product were fed diets supplemented with ceramide, sphingomyelin, glucosylceramide, lactosylceramide, and ganglioside G(D3) (a composition similar in amount and type to that of dairy products) to determine whether tumorigenesis caused by this category of genetic defect is suppressed. Sphingolipid feeding reduced the number of tumors in all regions of the intestine, and caused a marked redistribution of beta-catenin from a diffuse (cytosolic plus membrane) pattern to a more "normal" localization at mainly intercellular junctions between intestinal epithelial cells. The major digestion product of complex sphingolipids is sphingosine, and treatment of two human colon cancer cell lines in culture (SW480 and T84) with sphingosine reduced cytosolic and nuclear beta-catenin, inhibited growth, and induced cell death. Ceramides, particularly long-chain ceramides, also had effects. Thus, dietary sphingolipids, presumably via their digestion products, bypass or correct defect(s) in the APC/beta-catenin regulatory pathway. This may be at least one mechanism whereby dietary sphingolipids inhibit colon carcinogenesis, and might have implications for dietary intervention in human familial adenomatous polyposis and colon cancer.

Verapamil inhibits proliferation of LNCaP human prostate cancer cells influencing K+ channel gating.

The mechanisms of verapamil and tetraethylammonium (TEA) inhibition of voltage-gated K+ channels in LNCaP human prostate cancer cells were studied in whole-cell and outside/inside-out patch-clamp configurations. Rapidly activating outward K+ currents (I(K)) exhibited neither C-type, nor rapid (human ether á go-go-related gene-type) inactivation. With 2 mM [Mg(2+)](o), I(K) activation kinetics was independent of holding potential, suggesting the absence of ether á go-go-type K+ channels. Extracellular applications of TEA and verapamil (IC(50) = 11 microM) rapidly (12 s) inhibited I(K) in LNCaP cells. Blocking was also rapidly reversible. Intracellular TEA (1 mM), verapamil (1 mM), and membrane-impermeable N-methyl-verapamil (25 microM) did not influence whole-cell I(K), although both phenylalkylamines inhibited single-channel currents in inside-out patches. Extracellular application of N-methyl-verapamil (25 microM) had no influence on I(K). Our results are compatible with the hypothesis that, in LNCaP cells expressing C-type inactivation-deficient voltage-activated K+ channels, phenylalkylamines interact with an intracellular binding site, and probably an additional hydrophobic binding site that does not bind charged phenylalkylamines. The inhibiting effects of verapamil and TEA on I(K) were additive, suggesting independent K+-channel blocking mechanisms. Indeed, TEA (1 mM) reduced a single-channel conductance (from 7.3 +/- 0.5 to 3.2 +/- 0.4 pA at a membrane potential of +50 mV, n = 6), whereas verapamil (10 microM) reduced an open-channel probability (from 0.45 +/- 0.1 in control to 0.1 +/- 0.09 in verapamil-treated cells, n = 9). The inhibiting effects of verapamil and TEA on LNCaP cell proliferation were not multiplicative, suggesting that both share a common antiproliferative mechanism initiated through a K+ channel block.

Three mutations in v-Rel render it resistant to cleavage by cell-death protease caspase-3.

The retroviral oncoprotein v-Rel is a transcriptional activator in the Rel/NF-kappa B family. v-Rel causes rapidly fatal lymphomas in young chickens, and transforms and immortalizes chicken lymphoid cells in vitro. Several mutations that have enhanced the oncogenicity of v-Rel have been selected during in vitro and in vivo passage of v-Rel-containing retroviruses. In this report, we show that the C-terminal deletion and two point mutations (Asp-->Gly at residue 91 and Asp-->Asn at residue 437) in v-Rel make it resistant to cleavage by the cell-death protease caspase-3. In contrast, c-Rel, which has Asp residues at these sites, can be cleaved by caspase-3 in vitro as well as in vivo in cells induced to undergo apoptosis. We have characterized activities of v-Rel mutants with recreated single caspase-3 cleavage sites, two cleavage sites, or an introduced artificial cleavage site. All of these mutant v-Rel proteins are sensitive to caspase-3 cleavage in vitro, and show wild-type activity in terms of nuclear localization in chicken fibroblasts and DNA binding in vitro. Moreover, all caspase-3-sensitive v-Rel mutants transform chicken spleen cells in vitro and induce fatal lymphoid tumors in vivo to approximately the same extent as wild-type v-Rel. As with v-Rel mutants, caspase-3-resistant c-Rel mutants behave similarly to caspase-3-sensitive wild-type c-Rel in terms of DNA binding, transcriptional activation, in vitro transformation, and tumorigenicity. Mammalian c-Rel proteins can also be cleaved by caspase-3 in vitro, and a c-Rel mutant from a human pre-T lymphoma cell line is less sensitive than wild-type human c-Rel to cleavage by caspase-3. Taken together, these results demonstrate that specific mutations render oncogenic forms of Rel proteins resistant to cleavage by a cell-death caspase; however, the biological relevance of this resistance remains unclear. Nevertheless, to our knowledge, this is the first demonstration of mutations in caspase-3 recognition sites occurring during the evolution of an oncogenic protein.

Volume-regulated chloride conductance in the LNCaP human prostate cancer cell line.

Patch-clamp recordings were used to study ion currents induced by cell swelling caused by hypotonicity in human prostate cancer epithelial cells, LNCaP. The reversal potential of the swelling-evoked current suggested that Cl(-) was the primary charge carrier (termed I(Cl,swell)). The selectivity sequence of the underlying volume-regulated anion channels (VRACs) for different anions was Br(-) approximately I(-) > Cl(-) > F(-) > methanesulfonate >> glutamate, with relative permeability numbers of 1.26, 1.20, 1.0, 0.77, 0.49, and 0.036, respectively. The current-voltage patterns of the whole cell currents as well as single-channel currents showed moderate outward rectification. Unitary VRAC conductance was determined at 9.6 +/- 1.8 pS. Conventional Cl(-) channel blockers 5-nitro-2-(3-phenylpropylamino)benzoic acid (100 microM) and DIDS (100 microM) inhibited whole cell I(Cl,swell) in a voltage-dependent manner, with the block decreasing from 39.6 +/- 9.7% and 71.0 +/- 11. 0% at +50 mV to 26.2 +/- 7.2% and 14.5 +/- 6.6% at -100 mV, respectively. Verapamil (50 microM), a standard Ca(2+) antagonist and P-glycoprotein function inhibitor, depressed the current by a maximum of 15%. Protein tyrosine kinase inhibitors downregulated I(Cl,swell) (genistein with an IC(50) of 2.6 microM and lavendustin A by 60 +/- 14% at 1 microM). The protein tyrosine phosphatase inhibitor sodium orthovanadate (500 microM) stimulated I(Cl,swell) by 54 +/- 11%. We conclude that VRACs in human prostate cancer epithelial cells are modulated via protein tyrosine phosphorylation.