Tissue properties and respiratory kinematics of the tongue base and soft palate in the obese OSA minipig

Obesity is a common finding and a major pathogenetic factor in obstructive sleep apnea (OSA) in adults. To understand the mechanisms behind this, the present study investigated the tissue properties and respiratory kinematics of the tongue base and soft palate in the obese OSA minipig model. In 4 verified obese/OSA and 3 non-obese/non-OSA control minipigs, MRI fat-weighted images, ultrasound elastography (USE), and sleep video-fluoroscopy (SVF) were performed to quantify the fat composition, tissue stiffness, and respiratory kinematics of the tongue base and soft palate during sedated sleep. The results indicated that the fat composition gradually increased from the rostral to caudal tongue base, particularly in the posterior 1/3 of the tongue base, regardless of the presence of obesity and OSA. However, this trend was not seen in the soft palate and pharyngeal wall. The pharyngeal wall presented the highest fat composition as compared with the tongue base and soft palate. Overall, obese OSA minipigs showed stiffer tongue tissue than the controls, particularly in the rostral region of the tongue in obese Yucatan minipigs. The respiratory moving ranges of the soft palate were greater in both dorsal-ventral and rostral-caudal directions and during both respiratory and expiratory phases in OSA obese than control minipigs, and the largest moving ranges were seen in OSA obese Panepinto minipigs. The moving range of the tongue base was significantly smaller. These results suggest more fat infiltration in the caudal region of the tongue base regardless of the presence of obesity and/or OSA. The greater tissue stiffness of the tongue in obese OSA minipigs may result from altered neuromuscular drive.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

[Knowledge, Attitudes And Practice Of The Pupils Of The High School Famolo Coulibaly Of Kolokani On The HIV And The AIDS (Mali)]

INTRODUCTION

The epidemic of the AIDS is global. No country or territory is saved. Mali takes into account the preventive education in the AIDS in the sectorial programs of the Ministry of Education and the courses of study.

OBJECTIVE

to estimate the level of the Knowledge, Attitudes and Practice of the pupils regarding prevention of the HIV and the AIDS.

METHODS

it was about an exhaustive, quantitative and transverse survey led to the high school of Kolokani. The survey concerned 515 pupils questioned from 2 till 7 March 2007.

RESULTS

At the level of the knowledge the mode of transmission the most quoted by the pupils was the sexual intercourse with multiple partners (78.46 % for the boys and 71.22 % for the girls). Compared with the behavior, 62.89% of sexually active pupils used the condom in their last high-risk sexual intercourse. Only 25.05% of students reported having conducted a voluntary screening test. Attitudes of discrimination exist because 18.06 % of pupils have a feeling of fear towards the People Living with the HIV.

CONCLUSION

These results show that there is a risk of transmission of the HIV and the AIDS in schools. This has to motivate the intensification of the activities of raising sensitization and prevention to improve the indicators of prevention of this pandemic.

Infusion of ex-vivo expanded human TCR-αβ+ double-negative regulatory T cells delays onset of xenogeneic graft-versus-host disease

Despite the demonstration of potent immunosuppressive function of T cell receptor (TCR)-αβ⁺ double-negative regulatory T cells (DN T_regs ), scarce numbers and lack of effective expansion method limit their clinical applications. Here we describe an approach that allows for ∼3500-fold ex-vivo expansion of human DN T_regs within 3 weeks with > 97% purity. Ex-vivo-expanded DN T_regs suppress proliferation of polyclonally stimulated autologous T and B cells in vitro through direct cell-to-cell contact. In vivo, we demonstrate for the first time that infusion of human DN T_regs delayed an onset of xenogeneic graft-versus-host disease (GVHD) significantly in a humanized mouse model. Furthermore, preincubation of ex-vivo-expanded DN T_regs with a mechanistic target of rapamycin (mTOR) inhibitor rapamycin enhanced their immune regulatory function further. Taken together, this study demonstrates that human DN T_regs can be expanded ex vivo to therapeutic numbers. The expanded DN T_regs can suppress proliferation of T and B cells and attenuate GVHD, highlighting the potential clinical use of DN T_regs to mitigate GVHD.

The P2X7 receptor antagonist Brilliant Blue G reduces serum human interferon-γ in a humanized mouse model of graft-versus-host disease

Graft-versus-host disease (GVHD) remains a major problem after allogeneic haematopoietic stem cell transplantation, a curative therapy for haematological malignancies. Previous studies have demonstrated a role for the adenosine triphosphate (ATP)-gated P2X7 receptor channel in allogeneic mouse models of GVHD. In this study, injection of human peripheral blood mononuclear cells (PBMCs) into immunodeficient non-obese diabetic-severe combined immunodeficiency-interleukin (NOD-SCID-IL)-2Rγ^null (NSG) mice established a humanized mouse model of GVHD. This model was used to study the effect of P2X7 blockade in this disease. From five weeks post-PBMC injection, humanized mice exhibited clinical signs and histopathology characteristic of GVHD. The P2X7 antagonist, Brilliant Blue G (BBG), blocked ATP-induced cation uptake into both murine and human cells in vitro. Injection of BBG (50 mg/kg) into NSG mice did not affect engraftment of human leucocytes (predominantly T cells), or the clinical score and survival of mice. In contrast, BBG injection reduced circulating human interferon (IFN)-γ significantly, which was produced by human CD4⁺ and CD8⁺ T cells. BBG also reduced human T cell infiltration and apoptosis in target organs of GVHD. In conclusion, the P2X7 antagonist BBG reduced circulating IFN-γ in a humanized mouse model of GVHD supporting a potential role for P2X7 to alter the pathology of this disease in humans.

Cyclin D1 Restrains Oncogene-Induced Autophagy by Regulating the AMPK-LKB1 Signaling Axis

Autophagy activated after DNA damage or other stresses mitigates cellular damage by removing damaged proteins, lipids, and organelles. Activation of the master metabolic kinase AMPK enhances autophagy. Here we report that cyclin D1 restrains autophagy by modulating the activation of AMPK. In cell models of human breast cancer or in a cyclin D1-deficient model, we observed a cyclin D1-mediated reduction in AMPK activation. Mechanistic investigations showed that cyclin D1 inhibited mitochondrial function, promoted glycolysis, and reduced activation of AMPK (pT172), possibly through a mechanism that involves cyclin D1-Cdk4/Cdk6 phosphorylation of LKB1. Our findings suggest how AMPK activation by cyclin D1 may couple cell proliferation to energy homeostasis. Cancer Res; 77(13); 3391-405. ©2017 AACR.

Abstract B10: Cyclin D1 restrains oncogene-induced autophagy via phosphorylation of LKB1

Cyclin D1 is an important molecular driver of many human cancers. The cyclin D1 gene is amplified or overexpressed in up to half of human breast cancers and mammary-targeted overexpression of cyclin D1 is sufficient to induce mammary tumorigenesis in mice. Cyclin D1 encodes the regulatory subunit of the cyclin-dependent kinase (CDK) holoenzyme that phosphorylates several substrates including the retinoblastoma protein (pRb) to advance the G1S cell cycle checkpoint and promote DNA synthesis. Recent studies have implicated cell cycle regulators that govern G1S transition, in regulating cellular metabolism. Cyclin D1 phosphorylates and inactivates a nuclear encoded protein essential for mitochondrial biogenesis, Nrf1. In this manner cyclin D1 coordinates both nuclear and mitochondrial functions. Consistent with cyclin D1-dependent inhibition of mitochondrial biogenesis, pRB promotes and E2F-1 inhibits mitochondrial biogenesis. In addition to inhibiting mitochondrial biogenesis, cyclin D1 inhibits mitochondrial membrane potential, which may be in part due to binding VDAC.

Autophagy is a catabolic pathway activated in response to cellular stress such as oxidative or nutritional stress. It mitigates cellular damage via removal of insoluble and damaged proteins, lipids and organelles. Autophagy is enhanced by the phosphorylated and activated form of 5’-AMP-activated protein kinase (AMPK). We initiated the following study to directly test the effect of cyclin D1 has on cellular metabolism and autophagy. Herein, endogenous cyclin D1 restrained autophagy in breast cancer cells in tissue culture and in the mammary gland of mice. Using mammary epithelial-targeted deletion of cyclin D1 we show cyclin D1 restrains autophagy by reducing AMPK activation. Cyclin D1 may serve to couple cellular proliferation to cellular energy homeostasis.

Citation Format: Mathew Casimiro, Gabriele Di Sante, Emanuele Loro, Timothy Pestell, Sara Bisetto, Marco Velasco-Velázquez, Xuanmao Jiao, Zhiping Li, Chenguang Wang, Daniel Ly, Bin Zheng, Shen Che-Hung, Adam Ertel, Richard G. Pestell. Cyclin D1 restrains oncogene-induced autophagy via phosphorylation of LKB1. [abstract]. In: Proceedings of the Fourth AACR International Conference on Frontiers in Basic Cancer Research; 2015 Oct 23-26; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2016;76(3 Suppl):Abstract nr B10.

CD44 is prognostic for overall survival in the NCI randomized trial on breast conservation with 25 year follow-up

CD44 is a transmembrane glycoprotein involved in numerous cellular functions, including cell adhesion and extracellular matrix interactions. It is known to be functionally diverse, with alternative splice variants increasingly implicated as a marker for tumor-initiating stem cells associated with poor prognosis. Here, we evaluate CD44 as a potential marker of long-term breast cancer outcomes. Tissue specimens from patients treated on the National Cancer Institute 79-C-0111 randomized trial of breast conservation versus mastectomy between 1979 and 1987 were collected, and immunohistochemistry was performed using the standard isoform of CD44. Specimens were correlated with patient characteristics and outcomes. Survival analysis was performed using the log rank test. Fifty-one patients had evaluable tumor sections and available long-term clinical follow up data at a median follow up of 25.7 years. Significant predictors of OS were tumor size (median OFS 25.4 years for ≤2 cm vs. 7.5 years for >2 cm, p = 0.001), nodal status (median OS 17.2 years for node-negative patients vs. 6.7 years for node positive patients, p = 0.017), and CD44 expression (median OS 18.9 years for CD44 positive patients vs. 8.6 years for CD44 negative patients, p = 0.049). There was a trend toward increased PFS for patients with CD44 positive tumors (median PFS 17.9 vs. 4.3 years, p = 0.17), but this did not reach statistical significance. These findings illustrate the potential utility of CD44 as a prognostic marker for early stage breast cancer. Subgroup analysis in patients with lymph node involvement revealed CD44 positivity to be most strongly associated with increased survival, suggesting a potential role of CD44 in decision making for axillary management. As there is increasing interest in CD44 as a therapeutic target in ongoing clinical trials, the results of this study suggest additional investigation regarding the role CD44 in breast cancer is warranted.

An alpha-galactosylceramide C20:2 N-acyl variant enhances anti-inflammatory and regulatory T cell-independent responses that prevent type 1 diabetes

Protection from type 1 diabetes (T1D), a T helper type 1 (Th1)-mediated disease, is achievable in non-obese diabetic (NOD) mice by treatment with alpha-galactosylceramide (alpha-GalCer) glycolipids that stimulate CD1d-restricted invariant natural killer T (iNK T) cells. While we have reported previously that the C20:2 N-acyl variant of alpha-GalCer elicits a Th2-biased cytokine response and protects NOD mice from T1D more effectively than a form of alpha-GalCer that induces mixed Th1 and Th2 responses, it remained to determine whether this protection is accompanied by heightened anti-inflammatory responses. We show that treatment of NOD mice with C20:2 diminished the activation of 'inflammatory' interleukin (IL)-12 producing CD11c(high)CD8+ myeloid dendritic cells (mDCs) and augmented the function of 'tolerogenic' DCs more effectively than treatment with the prototypical iNKT cell activator KRN7000 (alpha-GalCer C26:0) that induces Th1- and Th2-type responses. These findings correlate with a reduced capacity of C20:2 to sustain the early transactivation of T, B and NK cells. They may also explain our observation that C20:2 activated iNK T cells depend less than KRN7000 activated iNK T cells upon regulation by regulatory T cells for cytokine secretion and protection from T1D. The enhanced anti-inflammatory properties of C20:2 relative to KRN7000 suggest that C20:2 should be evaluated further as a drug to induce iNK T cell-mediated protection from T1D in humans.

[HIV/AIDS prevalence among the attendees at the Center for Voluntary Anonymous Detection and Support in Pikine/Guediawaye, Senegal]

Within the framework of HIV/AIDS epidemic control, a Center for Voluntary Anonymous Detection and Support (CDVAA) was opened in March 2003 in Pikine/Guediawaye, Senegal. The purpose of this study was to analyze the prevalence of the HIV infection among attendees at the center over a one-year period as a basis for targeting the services of the CDVAA towards improving public health. This retrospective epidemiological study based on analysis of CDVAA attendee records was carried out from April 8, 2003 to April 7, 2004. The CDVAA in Pikine/Guediawaye shares premises with the Departmental Center for Popular and Sports Education. Sampling was exhaustive with inclusion of all people that attended the CDVAA during the study period. Study variables were age, sex, family status, educational level, ethnic group, religion, reason for detection, knowledge about HIV/AIDS prevention methods, results of the test, and, in case of infection, acceptance/refusal of referral to an appropriate management facility. Data were computed and analyzed using EpiInfo 6.04d software. The most common reason for detection was curiosity to know serologic status (69%). Test results were positive in 3% of cases. Infection was due to HIV1 in 65% of cases, HIV2 in 24%, and both (HIV1-HIV2 co-infection) in 11%. Ninety-one percent of attendees that underwent testing returned to pick-up their results. Sixty-eight percent of attendees that tested positive accepted referral to an appropriate management facility. HIV infection was significantly more frequent in attendees who were 24 years old, married, or illiterate and in attendees reporting risky behavior. To further encouraging progress already achieved, the CDVAA must improve the quality of its services and promote its activities as a means of familiarizing the target population on prevention of sexual transmitted diseases and HIV/AIDS, with a particular focus on safe behavior.

Regulation of DNaseY activity by actinin-α4 during apoptosis

DNaseY, a Ca(2+)- and Mg(2+)-dependent endonuclease, has been implicated in apoptotic DNA degradation; however, the molecular mechanisms controlling its involvement in this process have not been fully elucidated. We have obtained evidence from yeast two-hybrid screening and coimmunoprecipitation experiments that DNaseY interacted physically with actinin-alpha4 and this interaction significantly enhanced its endonuclease activity. Accordingly, simultaneous overexpression of both proteins in PC12 cells dramatically increased the rate of apoptosis in response to teniposide' VM26. However, overexpression of DNaseY alone neither triggered apoptosis nor facilitated cell death in response to VM26 or serum deprivation. Instead, the overexpression of DNaseY increased the production of single-strand DNA breaks and evoked a profound upregulation of DNA repair pathways. Taken together, our results point to a novel regulatory mechanism of DNaseY activity and offer an explanation for why cells must first cleave key DNA repair and replication proteins before the successful execution of apoptosis.

TIPS versus paracentesis for cirrhotic patients with refractory ascites

BACKGROUND

Ten per cent of cirrhotic patients develop refractory ascites, which carries substantial morbidity and has a one-year survival of less than 50 per cent. Patients with refractory ascites may benefit from transjugular intrahepatic portosystemic stent-shunts (TIPS).

OBJECTIVES

To compare TIPS versus paracentesis standard treatment in patients with refractory ascites due to cirrhosis with regard to overall short- and long-term mortality, treatment efficacy, and complications.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register (July 2003), The Cochrane Central Register of Controlled Trials on The Cochrane Library (Issue 1, 2003), MEDLINE (1966 to July 2003), EMBASE (1980 to July 2003), and CINAHL (1982 to July 2003). We supplemented the searches with reading through scientific citations, review of citations in relevant primary articles, and hand-searched abstracts from national meetings.

SELECTION CRITERIA

We included randomised clinical trials comparing TIPS and paracentesis with or without volume expanders for cirrhotic patients with refractory ascites.

DATA COLLECTION AND ANALYSIS

We evaluated the methodological quality of the randomised clinical trials by the generation of the allocation section, allocation concealment, and follow-up. Two independent observers extracted data from each trial. We contacted trial authors for additional information. Dichotomous outcomes were reported as odds ratio (OR) with 95% confidence interval (CI).

MAIN RESULTS

Four randomised clinical trials, including 264 patients, met the inclusion criteria. Methodological quality was moderate. Thirty-day mortality (OR 1.00, 95% CI 0.10 to 10.06, P = 1.0) and 24-month mortality (OR 1.17, 95% CI 0.52 to 2.66, P = 0.70) did not differ significantly between TIPS and paracentesis treatment. TIPS significantly reduced ascites re-accumulation at three months (OR 0.07, 95% CI 0.03 to 0.18, P < 0.00001) and at 12 months follow-up (OR 0.14, 95% CI 0.06 to 0.28, P < 0.00001). Hepatic encephalopathy occurred significantly more often in the TIPS group (OR 2.11, 95% CI 1.22 to 3.66, P = 0.008). Gastrointestinal bleeding (OR 0.82, 95% CI 0.36 to 1.84, P = 0.63), acute renal failure (OR 0.64, 95% CI 0.15 to 2.72, P = 0.55), septicemia/infection (OR 1.05, 95% CI 0.22 to 4.94, P = 0.96), and disseminated intravascular coagulation (OR 0.82, 95% CI 0.26 to 1.84, P = 0.63) did not differ significantly between groups.

REVIEWERS' CONCLUSIONS

TIPS removed ascites more effectively than paracentesis. After 12 months, the beneficial effects of TIPS on ascites was still present. Mortality, gastrointestinal bleeding, septicemia/infection, acute renal failure, and disseminated intravascular coagulation did not differ significantly between the two groups. Hepatic encephalopathy occurred significantly more often in the TIPS group.

Attachment of gelatin films to tissue using argon beam coagulator

Cross-linked gelatin films were bonded to heart muscle and to lung pleura and parenchyma using the electrical discharge of an argon beam radiofrequency coagulator. The bonds were stable in warm saline buffer for minutes to hours. Bonding was thought to partly occur through a mechanical interlock of film and tissue elements. The interdigitation of tissue and film arose during exposure to the argon beam, which denatured protein constituents of both, and created a fluidized state that rapidly coalesced.

Hairpin-forming peptide nucleic acid oligomers

A series of partially self-complementary peptide nucleic acid (PNA) oligomers was prepared. Examination of their melting behavior, circular dichroism spectra, and fluorescence properties reveals that these PNA oligomers exist as stem-loop ("hairpin") structures. Fluorescence is readily observed in hairpins containing a covalently linked, emissive acridine derivative which is, at least partially, intercalated in the duplex region of the PNA hairpin. The acridine fluorescence is quenched when an anthraquinone derivative is covalently attached to the PNA so that it is bound near the acridine in the hairpin structure. Acridine fluorescence is restored in hairpins containing both the anthraquinone and the acridine by increasing the temperature and melting the structure to its linear form or by opening the hairpin through formation of a hybrid duplex with complementary DNA. The latter process may form the basis for development of selective and sensitive DNA assays.

Peptide nucleic acid-DNA duplexes: long range hole migration from an internally linked anthraquinone

The discovery that peptide nucleic acids (PNA) mimic DNA and RNA by forming complementary duplex structures following Watson-Crick base pairing rules opens fields in biochemistry, diagnostics, and medicine for exploration. Progress requires the development of modified PNA duplexes having unique and well defined properties. We find that anthraquinone groups bound to internal positions of a PNA oligomer intercalate in the PNA-DNA hybrid. Their irradiation with near-UV light leads to electron transfer and oxidative damage at remote GG doublets on the complementary DNA strand. This behavior mimics that observed in related DNA duplexes and provides the first evidence for long range electron (hole) transport in PNA-DNA hybrid. Analysis of the mechanism for electron transport supports hole hopping.

Structural modification changes the DNA binding mode of cation-substituted anthraquinone photonucleases: association by intercalation or minor groove binding determines the DNA cleavage efficiency

The mode of binding anthraquinone derivatives, bearing positively charged ammonium side chains, to duplex DNA was investigated by optical and NMR spectroscopy. Absorption, circular dichroism, emission, and one- and two-dimensional homonuclear NMR spectroscopy show that mono- and dication-substituted quinones, AQS and 27AQS, bind primarily by intercalation. In contrast, these experiments indicate that the tetracationic anthraquinone 27AQS2 is bound nonintercalatively to duplex DNA. In particular, analysis of the NMR spectrum of 27AQS2 bound to a specially designed synthetic self-complementary dodecanucleotide (5'-CGCGAATTCGCG-3') shows it to be associated primarily with the minor groove of the central AATT sequence. The change in the DNA binding mode greatly affects the photophysical and photochemical properties of these photonucleases with DNA.