Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

Epigenetics: spotlight on type 2 diabetes and obesity

Type 2 diabetes (T2D) and obesity are the major public health problems. Substantial efforts have been made to define loci and variants contributing to the individual risk of these disorders. However, the overall risk explained by genetic variation is very modest. Epigenetics is one of the fastest growing research areas in biomedicine as changes in the epigenome are involved in many biological processes, impact on the risk for several complex diseases including diabetes and may explain susceptibility. In this review, we focus on the role of DNA methylation in contributing to the risk of T2D and obesity.

Increased hexosamine biosynthetic pathway flux dedifferentiates INS-1E cells and murine islets by an extracellular signal-regulated kinase (ERK)1/2-mediated signal transmission pathway

AIMS/HYPOTHESIS

Beta cell failure is caused by loss of cell mass, mostly by apoptosis, but also by simple dysfunction (decline of glucose-stimulated insulin secretion, downregulation of specific gene expression). Apoptosis and dysfunction are caused, at least in part, by lipoglucotoxicity. The mechanisms implicated are oxidative stress, increase in the hexosamine biosynthetic pathway (HBP) flux and endoplasmic reticulum (ER) stress. Oxidative stress plays a role in glucotoxicity-induced beta cell dedifferentiation, while glucotoxicity-induced ER stress has been mostly linked to beta cell apoptosis. We sought to clarify whether ER stress caused by increased HBP flux participates in a dedifferentiating response of beta cells, in the absence of relevant apoptosis.

METHODS

We used INS-1E cells and murine islets. We analysed the unfolded protein response and the expression profile of beta cells by real-time RT-PCR and western blot. The signal transmission pathway elicited by ER stress was investigated by real-time RT-PCR and immunofluorescence.

RESULTS

Glucosamine and high glucose induced ER stress, but did not decrease cell viability in INS-1E cells. ER stress caused dedifferentiation of beta cells, as shown by downregulation of beta cell markers and of the transcription factor, pancreatic and duodenal homeobox 1. Glucose-stimulated insulin secretion was inhibited. These effects were prevented by the chemical chaperone, 4-phenyl butyric acid. The extracellular signal-regulated kinase (ERK) signal transmission pathway was implicated, since its inhibition prevented the effects induced by glucosamine and high glucose.

CONCLUSIONS/INTERPRETATION

Glucotoxic ER stress dedifferentiates beta cells, in the absence of apoptosis, through a transcriptional response. These effects are mediated by the activation of ERK1/2.

Hepatocyte nuclear factor (HNF)-4alpha-driven epigenetic silencing of the human PED gene

AIMS/HYPOTHESIS

Overexpression of PED (also known as PEA15) determines insulin resistance and impaired insulin secretion and may contribute to progression toward type 2 diabetes. Recently, we found that the transcription factor hepatocyte nuclear factor (HNF)-4alpha binds to PED promoter and represses its transcription. However, the molecular details responsible for regulation of PED gene remain unclear.

METHODS

Here we used gain and loss of function approaches to investigate the hypothesis that HNF-4alpha controls chromatin remodelling at the PED promoter in human cell lines.

RESULTS

HNF-4alpha production and binding induce chromatin remodelling at the -250 to 50 region of PED, indicating that remodelling is limited to two nucleosomes located at the proximal promoter. Chromatin immunoprecipitation assays also revealed concomitant HNF-4alpha-induced deacetylation of histone H3 at Lys9 and Lys14, and increased dimethylation of histone H3 at Lys9. The latter was followed by reduction of histone H3 Lys4 dimethylation. HNF-4alpha was also shown to target the histone deacetylase complex associated with silencing mediator of retinoic acid and thyroid hormone receptor, both at the PED promoter, and at GRB14 and USP21 regulatory regions, leading to a reduction of mRNA levels. Moreover, HNF-4alpha silencing and PED overexpression were accompanied by a significant reduction of hepatic glycogen content.

CONCLUSIONS/INTERPRETATION

These results show that HNF-4alpha serves as a scaffold protein for histone deacetylase activities, thereby inhibiting liver expression of genes including PED. Dysregulation of these mechanisms may lead to upregulation of the PED gene in type 2 diabetes.

Haemorrhoidectomy with Ligasure vs conventional excisional techniques: meta-analysis of randomized controlled trials

OBJECTIVE

To compare the use of LigaSure devices with conventional excisional techniques, circular stapling and use of Harmonic Scalpel in patients with symptomatic haemorrhoids and to review literature on LigaSure technology (Valleylab Inc. USA).

METHOD

A literature review was performed using the National Library of Medicine's Pubmed Database using the keywords Ligasure, haemorrhoidectomy, vessel sealing technology. Randomized trials comparing LigaSure with other techniques of excisional haemorrhoidectomy with valid end points were reviewed in the present article and included in a quantitative meta-analysis.

RESULTS

There was no significant difference in the proportion of patients cured after Ligasure haemorrhoidectomy or other excisional techniques (P > 0.05). Patients treated with LigaSure had a significantly shorter operative time (P < 0.001), postoperative pain VAS Score (P < 0.001), wound healing time and time-off from work (P < 0.001), than the patients submitted to excisional techniques. Postoperative bleeding did not significantly differ between the two groups (P = 0.056); however, the surgeons observed a reduction of intra- and postoperative bleeding using LigaSure. In comparison to the circular stapler and Harmonic Scalpel the authors found similar postoperative outcomes and a slightly favourable trend for LigaSure regarding postoperative complications, ease of handling and length of the procedure.

CONCLUSION

Our meta-analysis shows that Ligasure haemorrhoidectomy is a fast procedure characterized by limited postoperative pain, short hospitalization, fast wound healing and convalescence.

A modification of primary closure for the treatment of pilonidal disease in day-care setting

AIM

The best surgical technique for treating sacrococcygeal pilonidal disease (PD) is still controversial. We evaluated the outcome of a modified primary closure for the treatment of pilonidal sinus.

METHOD

One hundred and fifty-two consecutive patients with PD, who underwent excision and primary closure under local anaesthesia according to our method, participated in this prospective study. The duration of operation and of hospitalization, postoperative pain, time to first mobilization, postoperative complications, time to resumption of work were assessed.

RESULTS

The median operative time was 30 min (range: 15-40); the median postoperative pain visual analogue scale score was 1 (range 0-3). All patients were mobilized between 2 and 4 h after surgery and discharged within 10 h. Postoperative complications included eight small debridements of an infected wound (5.3%) and one case of wound dehiscence (0.6%). No recurrence was detected during a median follow-up of 22 months (range: 10-34 months).

CONCLUSION

The low complication rate, near total absence of wound dehiscence, the compliance of the patients, the type of anaesthesia and the patient satisfaction makes this method effective. A randomized trial with long-term follow-up is warranted.

Botulinum toxin for recurrent anal fissure following lateral internal sphincterotomy

BACKGROUND

The aim of the study was to evaluate the efficacy of botulinum toxin injection in the treatment of recurrent anal fissure following lateral internal sphincterotomy.

METHODS

Eighty patients were treated with botulinum toxin (30 units Botox or 90 units Dysport), injected into two sites of the internal sphincter. Clinical and manometric results were recorded before and after treatment. If symptoms persisted at 2 months, the examiners could decide to re-treat the patient. The same preparation of serotype A of botulinum neurotoxin was used for reinjection.

RESULTS

One month after injection there was complete healing in 54 patients (68 per cent). Eight patients (10 per cent) reported mild incontinence of flatus that had disappeared spontaneously within 2 months. At 2 months, 59 patients (74 per cent) had a healing scar. After reinjection, 11 of 21 re-treated patients reported mild incontinence to flatus that lasted for a few weeks and resolved spontaneously. Anorectal manometry at 1 month demonstrated a significant reduction in both resting anal pressure and maximum voluntary squeeze pressure (P < 0.001). There were no relapses during a mean value of 57.9 months of follow-up.

CONCLUSION

Botulinum toxin is efficacious in patients with recurrent anal fissure following lateral internal sphincterotomy.

Randomized clinical trial of LigaSure and conventional diathermy haemorrhoidectomy

BACKGROUND

The aim of this randomized prospective trial was to compare LigaSure and conventional diathermy haemorrhoidectomy.

METHODS

Two hundred and eighty-four patients with grade III or IV haemorrhoids were randomized to LigaSure or diathermy (Milligan-Morgan) haemorrhoidectomy as a day-case procedure. Operating time, postoperative pain score, hospital stay, postoperative complications, wound healing time and time to return to normal activities were assessed. Thirty-four patients were lost to follow-up.

RESULTS

The mean operating time for LigaSure haemorrhoidectomy was significantly shorter than that for diathermy (P = 0.011). Patients treated with LigaSure had significantly less postoperative pain (measured on a visual analogue scale; P = 0.010), a shorter wound healing time (defined as time to absence of swelling; P = 0.012) and less time off work (P = 0.010) than patients who had diathermy. Neither postoperative complications nor mean hospital stay (day-case surgery) were significantly different.

CONCLUSION

LigaSure haemorrhoidectomy demonstrates simplicity, reproducibility, a low complication rate, fast wound healing, a quick return to work and reduced postoperative pain.

[Methodology assessment of the first-aid in a company]

The Ministerial Decree 388/03 establishes the first aid duties and organisation. It classifies the health firms into three groups, according to the types of activities carried out, to the number of the employees involved, and to the risks linked to it. The membership of a firm to a group reflects upon its standard equipment of facilities, the training required for the employees and the duties of communication to carry out to the Health Service. During the activity of vigilance we have verified that a lot of firms, belonging to our territory, have not applied correctly the body of rules regarding the first aid. For this reason a project aiming at providing information about the application of this decree has been started.

[Total gastrectomy extended to the head of the pancreas and the liver with D4 lymphadenectomy for well-differentiated gastric carcinoma]

Adenocarcinoma of the stomach is the second most common cancer worldwide. Early diagnosis and an adequate surgical approach could save live. Surgical approach is conditioned by the extension of the disease and the presence of metastases. Extended lymph-node dissection (D2) has been generally accepted as a standard treatment modality. However, the role of the super-extended lymphadenectomy (D4) for gastric cancer has not been established.

[Duodenocephalopancreatectomy with pylorus sparing and occlusion of the main bile duct with fibrin glue]

The leakage of pancreaticojejunostomy represents the main technical post-operative complication after pancreaticoduodenectomy. Because pancreatic fistula can be the source of morbidity and mortality and it is related to the integrity of the pancreatic-enteric anastomosis, a number of technical modification have been suggested, including pancreaticojejunostomy, pancreaticogastrostomy and occlusion of the main pancreatic duct with fibrin glue. The incidence of leakage is particularly high in case of narrow ducts and tender pancreatic glands; in such conditions some experiences in literature suggest the technique of occlusion of the main pancreatic duct with fibrin glue.

[Argentine consensus on sleep-related respiratory disorders]

Due to the increased interest of the medical community in sleep disorders an experts meeting was called to establish common criteria for diagnosis, treatment and management of these disorders. Adult prevalence of sleep apnea/hypopnea syndrome (SA/HS) is about 2-4% and increases in the elderly. Snoring and excessive daytime somnolence (EDS) are habitual symptoms. Increased risk to cardiovascular disorders and traffic accidents are the major complications. Increased upper airways resistance syndrome is a recently described syndrome which also involves EDS. A standardized questionnaire was developed and its use was recommended in order to evaluate patients with respiratory sleep disorders (RSD). Polysomnography was established as gold standard in the diagnosis of RSD. Minimal requirement of split night studies and screening studies was also standardized and specific indications were summarized. Medical treatment of obesity in relationship to RSD was analyzed. Nasal continuous positive airways pressure (CPAP) was established as the first choice treatment of SA/HS. Titration of CPAP was standardized. Oral appliances with mandibular advancement could be considered in the treatment of snoring patients without SA/HS and in patients with increased upper airways resistance syndrome. Uvulopalatopharingoplasty can only be performed in snoring patients in whom the presence of SA/HS has been dismissed by polysomnography. Management of patients must include periodic clinical control. EDS must be determined by Epworth test. In order to evaluate CPAP compliance the use of time-controlled devices is highly recommended.

Whitehead's hemorrhoidectomy. A useful surgical procedure in selected cases

At the present time Milligan-Morgan's operation is the most diffusely employed and is widely considered to be the most effective of the various surgical techniques for the treatment of hemorrhoids. In this study we report our experience with Whitehead's radical hemorrhoidectomy. In a 5-year period, 1450 patients with hemorrhoids were treated at our Coloproctologic Unit. We routinely carry out the Milligan-Morgan operation. Nevertheless, in 26 patients the Milligan-Morgan operation was judged to be impossible to perform, in that the prolapsed hemorrhoids were completely irreducible and it was not possible to distinguish and separate the three piles. These patients thus underwent Whitehead's radical hemorroidectomy. All the patients who underwent Whitehead's operation were discharged within the fifth post-operative day. No episodes of incontinence were observed in any patient. The patients were followed for three years after the operation. In only one case did we verify an anal substenosis three months after the operation, which resolved after the use of anal dilators for one month. The stenosis did not recur in the course of follow-up. There were no cases of mucosal ectropion. In conclusion, the type of hemorrhoidectomy which a surgeon performs is primarily based on the surgeon's experience and training. Nevertheless, a competently performed Whitehead's hemorrhoidectomy can give satisfying results. These results are explained by improved knowledge of the anatomy of the anal region and a more accurate surgical technique. On the basis of our experience we believe that Whitehead's hemorrhoidectomy still has its place in selected cases with precise indications.

Value of extended lymph node dissection in the treatment of gastric cancer

Regional lymph node metastasis is a critical prognostic factor in gastric cancer, and extended lymph node dissection and routine microscopic examination of all resected nodes could potentially provide accurate information regarding lymph node status. On the other hand, the therapeutic value of extended lymph node dissection is controversial. While retrospective and prospective non-randomised comparative studies have shown that extended lymph node dissection significantly improves the survival rate, prospective randomised trials have failed to demonstrate the efficacy of extended dissection, although the number of patients in these studies was limited. The present review of the literature therefore considers the prognostic significance of regional lymph node metastases and the therapeutic efficacy of lymph node dissection performed for gastric cancer.

Sleep-disordered breathing in a predominantly African-American pediatric population

The goal of this study was to characterize sleep and respiratory parameters in children with sleep-disordered breathing (SDB) as compared to children without SDB. Data are from 198 children and adolescents referred for sleep center evaluation, 128 of whom were diagnosed with SDB. In children with SDB, obesity (> 95% wgt for age) was more common than being severely underweight (< 5% wgt for age), but only the older children with SDB were heavier than age-matched normal sleepers. Children with SDB had increased EEG arousals; sleep architecture was not otherwise significantly different from the non-SDB group. African-American children with SDB had significantly greater oxygen desaturation with obstructive events compared to Caucasian and Latino children. It appears that the role of obesity as a risk factor for obstructive sleep apnea (OSA) increases in children above the age of 8-years. Additionally, African-American children with SDB may be at increased risk for hypoxemia and cardiovascular consequences of SDB.

Resuscitation with increasing doses of diaspirin crosslinked hemoglobin in swine

This study examined the effects of administering 0.5, 4, 10, and 30 mL/kg of Diaspirin Crosslinked Hemoglobin (DCLHb) in a swine model of non-lethal hemorrhagic shock. Thirty unanesthetized animals were bled (30 mL/kg, 1 mL/kg/min) and either recovered without treatment (Untreated Control, UC) or infused with 10 g/dL DCLHb (0.5, 4.0, 10 or 30 mL/kg at 1 mL/kg/min) or Lactated Ringer (LR, 90 mL/kg at 3 mL/kg/min). DCLHb caused dose-related increases in MAP. Both the 10 and 30 mL/kg doses of DCLHb increased MAP more than UC or LR. Lower doses of DCLHb and LR had effects on MAP similar to UC. After hemorrhage, CO increased in all groups. The effect of DCLHb on CO was dose-related. Only LR and 30 mL/kg of DCLHb transiently (through 90 min) increased CO more than UC. CO in animals given lower doses of DCLHb was comparable to UC. DCLHb (10 and 30 mL/kg) improved base excess and lactate concentrations, two indices of global perfusion, more rapidly and to a greater extent than either UC or LR. In this swine model of hemorrhage, even small doses of DCLHb exerted measurable beneficial effects on blood pressure and perfusion.

Resuscitation with Diaspirin Crosslinked Hemoglobin in a pig model of hemorrhagic shock

The efficacy of Diaspirin Crosslinked Hemoglobin (DCLHb) as a resuscitative fluid in hemorrhagic shock was compared to another colloid solution (human serum albumin, HSA) and a crystalloid solution (Lactated Ringer's, LR). Hemorrhage (35 mL/kg) was followed by isovolemic exchange then volume replacement. This modeled the clinical situation where resuscitative fluids are administered prior to stopping the hemorrhage, the hemorrhage is stopped, then blood volume is restored. Four combinations of resuscitative fluids were evaluated during isovolemic exchange: volume replacement: DCLHb:LR, HSA:LR, HSA:HSA and LR:LR. All doses were 10 mL/kg:35 mL/kg except LR:LR which was 10 mL/kg:125 mL/kg. Volume replacement was followed by a stabilization period and reinfusion of shed blood (35 mL/kg). MAP increased most rapidly using DCLHb (from 48 to 102 mmHg after 10 min of isovolemic exchange) and was maintained for at least 2 hours. Arterial oxygen content and acid-base status were significantly improved after resuscitation with DCLHb:LR vs. other resuscitative therapies. In conclusion, DCLHb:LR was an effective resuscitative therapy in treatment of hemorrhagic shock.

Effects of intravenous infusions of diaspirin cross-linked hemoglobin (DCLHb) on sheep

The purpose of this study was to compare the cardiopulmonary, hematologic, and immunologic responses of unanesthetized sheep to single, "topload", intravenous infusions of either 10 mL/Kg or 40 mL/Kg of Diaspirin Cross-Linked Hemoglobin, 10 mL/Kg or 40 mL/Kg of a Human Serum Albumin (HSA) solution oncotically adjusted with human serum albumin to approximately match the oncotic pressure of the DCLHb, or 10 mL/Kg of Erythrocyte Hemolysate solution prepared in a manner similar to that commonly described in the literature and referred to as "stroma free hemoglobin". Solutions were infused at a rate of 1 mL/Kg/minute and animals were monitored for 72 hours after infusion. These studies demonstrated that in sheep infusion of either DCLHb or HSA solutions was well tolerated and did not produce a significant increase in plasma C3a levels, an increase in the plasma concentration of thromboxane B2, or unexpected fluid shifts. In contrast, infusion of the Erythrocyte Hemolysate produced a greater than 10-fold increase in plasma C3a concentrations, a greater than 6000-fold increase in plasma TxB2 concentration, significant fluid shifts, and changes in a variety of other parameters consistent with induction of a dramatic inflammatory response. These results indicate that appropriately prepared and purified DCLHb solutions do not elicit an inflammatory reaction in sheep.

Beta-hexosaminidase activity in alcoholic fatty liver and in CCl4-induced liver fibrosis of the rat

beta-Hexosaminidase (Hex) activity was previously found to be increased in the sera of patients with liver cirrhosis, cholestasis and acute alcohol intoxication, as well as in rats with CCl4-induced liver cirrhosis. We studied this enzymatic activity in the sera and liver tissue of rats with alcoholic fatty liver due to prolonged alcohol intake and CCl4-induced liver fibrosis in association with moderate alterations in liver function tests. Serum and liver Hex activity did not show any significant change in both experimental models. These data suggest that Hex is not an alcohol-induced enzyme, and that severe, but not moderate, liver damage can determine the increase in this lysosomal enzymatic activity.

Angiotensin-converting enzyme activity in experimental alcoholic fatty liver of the rat

Angiotensin-converting enzyme (ACE) activity was found increased in serum of patients with chronic alcoholism. We studied this enzymatic activity in serum and liver tissue of rats with alcoholic fatty liver due to prolonged intake of ethanol with a liquid diet, according to De Carli and Lieber. Serum and liver ACE activity did not show any significant increase in rats with alcoholic fatty liver when compared with controls, whereas gamma-glutamyltransferase activity exhibited a striking enhancement in serum and liver. Our data suggest that ACE is not an alcohol-induced enzyme in the experimental rat model.