Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Immunofluorescence protocol for localizing protein targets in brain tissue from diverse model and non-model mammals

Previous immunostaining protocols are highly specific for model organisms and often not suitable for diverse specimens that are non-perfused and over-fixed (i.e., tissues sitting in fixatives for months/year). Here, we present an immunofluorescence protocol for localizing protein targets in brain tissue from 11 model and non-model mammals. We describe preparation of both fresh and fixed tissues including steps for deparaffinization, fixation, and cryoprotection. We then detail immunofluorescence procedures including antigen retrieval, reducing autofluorescence, nuclear staining, mounting, and image collection.

Transcription, structure, and organoids translate time across the lifespan of humans and great apes

How the neural structures supporting human cognition developed and arose in evolution is an enduring question of interest. Yet, we still lack appropriate procedures to align ages across primates, and this lacuna has hindered progress in understanding the evolution of biological programs. We generated a dataset of unprecedented size consisting of 573 time points from abrupt and gradual changes in behavior, anatomy, and transcription across human and 8 nonhuman primate species. We included time points from diverse human populations to capture within-species variation in the generation of cross-species age alignments. We also extracted corresponding ages from organoids. The identification of corresponding ages across the lifespan of 8 primate species, including apes (e.g., orangutans, gorillas) and monkeys (i.e., marmosets, macaques), reveals that some biological pathways are extended in humans compared with some nonhuman primates. Notably, the human lifespan is unusually extended relative to studied nonhuman primates demonstrating that very old age is a phase of life in humans that does not map to other studied primate species. More generally, our work prompts a reevaluation in the choice of a model system to understand aging given very old age in humans is a period of life without a clear counterpart in great apes.

Spatial control of astrogenesis progression by cortical arealization genes

Sizes of neuronal, astroglial and oligodendroglial complements forming the neonatal cerebral cortex largely depend on rates at which pallial stem cells give rise to lineage-committed progenitors and the latter ones progress to mature cell types. Here, we investigated the spatial articulation of pallial stem cells' (SCs) commitment to astrogenesis as well as the progression of committed astroglial progenitors (APs) to differentiated astrocytes, by clonal and kinetic profiling of pallial precursors. We found that caudal-medial (CM) SCs are more prone to astrogenesis than rostro-lateral (RL) ones, while RL-committed APs are more keen to proliferate than CM ones. Next, we assessed the control of these phenomena by 2 key transcription factor genes mastering regionalization of the early cortical primordium, Emx2 and Foxg1, via lentiviral somatic transgenesis, epistasis assays, and ad hoc rescue assays. We demonstrated that preferential CM SCs progression to astrogenesis is promoted by Emx2, mainly via Couptf1, Nfia, and Sox9 upregulation, while Foxg1 antagonizes such progression to some extent, likely via repression of Zbtb20. Finally, we showed that Foxg1 and Emx2 may be implicated-asymmetrically and antithetically-in shaping distinctive proliferative/differentiative behaviors displayed by APs in hippocampus and neocortex.

Synaptic boutons are smaller in chandelier cell cartridges in autism

Chandelier (Ch) cells are cortical interneurons with axon terminal structures known as cartridges that synapse on the axon initial segment of excitatory pyramidal neurons. Previous studies indicate that the number of Ch cells is decreased in autism, and that GABA receptors are decreased in the Ch cell synaptic target in the prefrontal cortex. To further identify Ch cell alterations, we examined whether the length of cartridges, and the number, density, and size of Ch cell synaptic boutons, differed in the prefrontal cortex of cases with autism versus control cases. We collected samples of postmortem human prefrontal cortex (Brodmann Area (BA) 9, 46, and 47) from 20 cases with autism and 20 age- and sex-matched control cases. Ch cells were labeled using an antibody against parvalbumin, a marker that labeles soma, cartridges, and synaptic boutons. We found no significant difference in the average length of cartridges, or in the total number or density of boutons in control subjects vs. subjects with autism. However, we found a significant decrease in the size of Ch cell boutons in those with autism. The reduced size of Ch cell boutons may result in reduced inhibitory signal transmission and impact the balance of excitation to inhibition in the prefrontal cortex in autism.

Evolution of astrocytes: From invertebrates to vertebrates

The central nervous system (CNS) shows incredible diversity across evolution at the anatomical, cellular, molecular, and functional levels. Over the past decades, neuronal cell number and heterogeneity, together with differences in the number and types of neuro-active substances, axonal conduction, velocity, and modes of synaptic transmission, have been rigorously investigated in comparative neuroscience studies. However, astrocytes, a specific type of glial cell in the CNS, play pivotal roles in regulating these features and thus are crucial for the brain’s development and evolution. While special attention has been paid to mammalian astrocytes, we still do not have a clear definition of what an astrocyte is from a broader evolutionary perspective, and there are very few studies on astroglia-like structures across all vertebrates. Here, I elucidate what we know thus far about astrocytes and astrocyte-like cells across vertebrates. This information expands our understanding of how astrocytes evolved to become more complex and extremely specialized cells in mammals and how they are relevant to the structure and function of the vertebrate brain.

Decreased number and increased activation state of astrocytes in gray and white matter of the prefrontal cortex in autism

The cerebral cortex presents with alterations in the number of specific cell types in autism spectrum disorder (ASD). Astrocytes have many functions in the brain including a role in higher cognitive functions and in inflammatory brain processes. Therefore, an alteration in number, function, and/or activation state of astrocytes, could be present in ASD. We quantified astrocyte number in the gray and white matter of the prefrontal cortex-BA9, BA46, and BA47-in 15 ASD and 15 age- and sex-matched control cases. We labeled astrocytes with antibodies against the protein GFAP and S100β, markers of astrocytes. We found a significant decrease in the number of astrocytes in the gray and white matter of all prefrontal areas of interest with both markers. We also found an increased state of activation of GFAP+ astrocytes in all areas. A reduced number of astrocytes in the cerebral cortex in ASD could lead to impaired synaptic function and disrupted connectivity. An increased astrocyte activation may indicate a chronic mild inflammatory state of the cerebral cortex in ASD. Overall, we found that astrocytes are disrupted in ASD.

Redefining varicose projection astrocytes in primates

Varicose projection astrocytes (VP-As) are found in the cerebral cortex and have been described to be specific to humans and chimpanzees. To further examine the phylogenetic distribution of this cell type, we analyzed cortical tissue from several primates ranging from primitive primates to primates evolutionary closer to human such as apes. We specifically analyzed tissue from four strepsirrhine species, one tarsier, six species of platyrrhine monkeys, ten species of cercopithecoid monkeys, two hylobatid ape species, four to six cases each of chimpanzee, bonobo, gorilla, and orangutan, and thirteen human. We found that VP-As were present only in human and other apes (hominoids) and were absent in all other species. We showed that VP-As are localized to layer VI and the superficial white matter of the cortex. The presence of VP-As co-occured with interlaminar astrocytes that also had varicosities in their processes. Due to their location, their long tangential processes, and their irregular presence within species, we propose that VP-As are astrocytes that develop varicosities under specific conditions and that are not a distinct astrocyte type.

Neuronal and glial cell number is altered in a cortical layer-specific manner in autism

LAY ABSTRACT

The cerebral cortex affected with autism spectrum disorder presents changes in the number of neurons and glia cells, possibly leading to a dysregulation of brain circuits and affecting behavior. However, little is known about cell number alteration in specific layers of the cortex in autism spectrum disorder. We found an increase in the number of neurons and a decrease in the number of astrocytes in specific layers of the prefrontal cortex in postmortem human brains from autism spectrum disorder cases. We hypothesize that this may be due to a failure in neural stem cells to shift differentiation from neurons to glial cells during prenatal brain development. These data provide key anatomical findings that contribute to the bases of autism spectrum disorder pathogenesis.

Chandelier Cartridge Density Is Reduced in the Prefrontal Cortex in Autism

An alteration in the balance of excitation-inhibition has been proposed as a common characteristic of the cerebral cortex in autism, which may be due to an alteration in the number and/or function of the excitatory and/or inhibitory cells that form the cortical circuitry. We previously found a decreased number of the parvalbumin (PV)+ interneuron known as Chandelier (Ch) cell in the prefrontal cortex in autism. This decrease could result from a decreased number of Ch cells, but also from decreased PV protein expression by Ch cells. To further determine if Ch cell number is altered in autism, we quantified the number of Ch cells following a different approach and different patient cohort than in our previous studies. We quantified the number of Ch cell cartridges-rather than Ch cell somata-that expressed GAT1-rather than PV. Specifically, we quantified GAT1+ cartridges in prefrontal areas BA9, BA46, and BA47 of 11 cases with autism and 11 control cases. We found that the density of GAT1+ cartridges was decreased in autism in all areas and layers. Whether this alteration is cause or effect remains unclear but could result from alterations that take place during cortical prenatal and/or postnatal development.

Foxg1 Antagonizes Neocortical Stem Cell Progression to Astrogenesis

Neocortical astrogenesis follows neuronogenesis and precedes oligogenesis. Among key factors dictating its temporal articulation, there are progression rates of pallial stem cells (SCs) towards astroglial lineages as well as activation rates of astrocyte differentiation programs in response to extrinsic gliogenic cues. In this study, we showed that high Foxg1 SC expression antagonizes astrocyte generation, while stimulating SC self-renewal and committing SCs to neuronogenesis. We found that mechanisms underlying this activity are mainly cell autonomous and highly pleiotropic. They include a concerted downregulation of 4 key effectors channeling neural SCs to astroglial fates, as well as defective activation of core molecular machineries implementing astroglial differentiation programs. Next, we found that SC Foxg1 levels specifically decline during the neuronogenic-to-gliogenic transition, pointing to a pivotal Foxg1 role in temporal modulation of astrogenesis. Finally, we showed that Foxg1 inhibits astrogenesis from human neocortical precursors, suggesting that this is an evolutionarily ancient trait.

Cortical Interlaminar Astrocytes Are Generated Prenatally, Mature Postnatally, and Express Unique Markers in Human and Nonhuman Primates

Interlaminar astrocytes (ILAs) are a subset of cortical astrocytes that reside in layer I, express GFAP, have a soma contacting the pia, and contain long interlaminar processes that extend through several cortical layers. We studied the prenatal and postnatal development of ILAs in three species of primates (rhesus macaque, chimpanzee, and human). We found that ILAs are generated prenatally likely from radial glial (RG) cells, that ILAs proliferate locally during gestation, and that ILAs extend interlaminar processes during postnatal stages of development. We showed that the density and morphological complexity of ILAs increase with age, and that ILAs express multiple markers that are expressed by RG cells (Pax6, Sox2, and Nestin), specific to inner and outer RG cells (Cryab and Hopx), and astrocyte markers (S100β, Aqp4, and GLAST) in prenatal stages and in adult. Finally, we demonstrated that rudimentary ILAs in mouse also express the RG markers Pax6, Sox2, and Nestin, but do not express S100β, Cryab, or Hopx, and that the density and morphological complexity of ILAs differ between primate species and mouse. Together these findings contribute new information on astrogenesis of this unique class of cells and suggest a lineal relationship between RG cells and ILAs.

Cortical interlaminar astrocytes across the therian mammal radiation

Interlaminar astrocytes (ILA) in the cerebral cortex possess a soma in layer I and extend an interlaminar process that runs perpendicular to the pia into deeper cortical layers. We examined cerebral cortex from 46 species that encompassed most orders of therian mammalians, including 22 primate species. We described two distinct cell types with interlaminar processes that have been referred to as ILA, that we termed pial ILA and supial ILA. ILA subtypes differ in somatic morphology, position in layer I, and presence across species. We further described rudimentary ILA that have short GFAP⁺ processes that do not exit layer I, and "typical" ILA with longer GFAP⁺ processes that exit layer I. Pial ILA were present in all mammalian species analyzed, with typical ILA observed in Primates, Scandentia, Chiroptera, Carnivora, Artiodactyla, Hyracoidea, and Proboscidea. Subpial ILA were absent in Marsupialia, and typical subpial ILA were only found in Primate. We focused on the properties of pial ILA by investigating the molecular properties of pial ILA and confirming their astrocytic nature. We found that while the density of pial ILA somata only varied slightly, the complexity of ILA processes varied greatly across species. Primates, specifically bonobo, chimpanzee, orangutan, and human, exhibited pial ILA with the highest complexity. We showed that interlaminar processes contact neurons, pia, and capillaries, suggesting a potential role for ILA in the blood-brain barrier and facilitating communication among cortical neurons, astrocytes, capillaries, meninges, and cerebrospinal fluid.

Emx2 as a novel tool to suppress glioblastoma

Glioblastoma is a devastating CNS tumour for which no cure is presently available. We wondered if manipulation of Emx2, which normally antagonizes cortico-cerebral astrogenesis by inhibiting proliferation of astrocyte progenitors, may be employed to counteract it. We found that Emx2 overexpression induced the collapse of seven out of seven in vitro tested glioblastoma cell lines. Moreover, it suppressed four out of four of these lines in vivo. As proven by dedicated rescue assays, the antioncogenic activity of Emx2 originated from its impact on at least six metabolic nodes, which accounts for the robustness of its effect. Finally, in two out of two tested lines, the tumor culture collapse was also achieved when Emx2 was driven by a neural stem cell-specific promoter, likely active within tumor-initiating cells. All that points to Emx2 as a novel, promising tool for therapy of glioblastoma and prevention of its recurrencies.

Hypokalemia during antibiotic treatment for bone and joint infections

PURPOSE

During treatment of bone and joint infections (BJIs) with multiple antibiotic therapy, hypokalemia has been reported as a rare side effect. The aim of this study was to evaluate incidence and risk factors for hypokalemia in a cohort of patients treated with multidrug therapy for BJIs, in a single center.

METHODS

We retrospectively reviewed 331 clinical files of 150 consecutive patients (65% males; median age 59 years, 95% CI 55-62) admitted repeatedly to our Osteomyelitis Department for treatment of chronic BJIs. Besides surgical debridement, patients received a combination of oral and intravenous antibiotics. Routine laboratory tests were performed at admittance and repeated at least weekly. Possible hypokalemia risk factors were recorded and analyzed.

RESULTS

Progressive kalemia reduction occurred in > 39% of patients during hospitalization; prevalence of marked hypokalemia (K ⁺ < 3.5 mEq/l) increased from 5% at admission to 11% (up to 22%) at day 14. Correlated factors were: age ≥ 68 years (p = 0.033), low serum albumin (p = 0.034), treatment with vancomycin (p < 0.001), rifampicin (p = 0.017) and ciprofloxacin (p < 0.001) and use of thiazide (p = 0.007) or loop diuretics (p = 0.029 for K ⁺ < 3.5 mEq/l). At multivariate regression analysis, the main determinants of hypokalemia were simultaneous use of diuretics (p = 0.007) and older age (p < 0.049).

CONCLUSIONS

Appearance of severe hypokalemia is a frequent event among patients treated for BJIs with multiple antibiotic therapy, when this is prescribed in older age patients and associated with simultaneous use of diuretics. Due to possible increase in mortality risk in the short term, particular caution should be paid during intensive antibiotic treatment in these groups of patients.

Spontaneous Disappearance of Juxta-Sylvian Cyst: MRI Study and Clinical Evaluations

Several cystic lesions may involve the temporal lobe including arachnoid, choroidal fissure and juxta-sylvian cysts. We reported a case of appearance, increase and spontaneous disappearance of a juxta-sylvian cyst in a young girl with headache studied by MRI between 1990 and 2003. In agreement with previous reports, the sudden disappearance, without a history of trauma, could be the result of an osmotic effect that shifted CSF inside the cyst, leading to an increase in osmotic pressure and rupture of the cyst wall.

Inflammation and Atherosclerosis: The Role of TNF and TNF Receptors Polymorphisms in Coronary Artery Disease

Inflammation plays an important role in the pathogenesis of atherosclerosis and coronary syndromes; moreover, various lines of evidence suggest that genetic factors contribute significantly to the risk of coronary artery disease (CAD). Through its effects on endothelial function, coagulation, insulin resistance and lipid metabolism, the proinflammatory cytokine TNF could be involved in cardiovascular pathophysiology. The aim of our study is to analyze whether TNF gene promoter (-308 G/A; −857 G/A) and TNF receptor polymorphisms (TNFR1 MspA1 I exon 1 and TNFR2 Nla III exon 6) show involvement in CAD predisposition in a group of Italian patients compared with healthy controls. Genotyping was performed by PCR-RFLP. Consecutive Italian patients with angiographically proven CAD (n= 248) were compared with controls (n=241), matched for age, sex and geographical origins. CAD patients showed a higher frequency of the TNF −308 A allele than healthy controls (p=0.046). After stratification according to risk factors for CAD, our analysis revealed that CAD patients with diabetes (p=0.042) and CAD patients without hypertension (p=0.0495) displayed a higher frequency of the TNF −308 AA genotype compared with healthy controls. Our data stress the inflammatory nature of CAD and show a possible involvement of TNF −308G/A promoter polymorphisms in the predisposition to the development of this disease. The less frequent A allele seems to be a predisposing factor for development of CAD in particular pathological settings associated with the disease itself, such as diabetes.

The-374T/A Variant of the Rage Gene Promoter is Associated with Clinical Restenosis after Coronary Stent Placement

Upregulation of the receptor for advanced glycation end products (RAGE) may play a crucial role in neointimal formation upon vessel injury. The −374T/A variant of the RAGE gene promoter, which has been associated with an altered expression of the cell-surface receptor, could exert a protective effect toward the development of vascular disease. The aim of this study is to determine the impact of this common genetic variant in the occurrence of clinical in-stent restenosis after coronary stent implantation. The −374T/A polymorphism of the RAGE gene promoter was evaluated by PCR-RFLPs in 267 patients with coronary artery disease who underwent coronary stent implantation and a subsequent coronary angiography 6–9 months later for suspected restenosis. In-stent restenosis was assessed by means of quantitative angiography. Carriers of the-374AA genotype showed a significantly reduced risk of developing restenosis after percutaneous transluminal intervention than non-carriers. To determine whether the protective effect of the homozygous AA genotype toward clinical restenosis was independent of potential confounders, we performed multivariable logistic regression analysis. After allowance for clinical and biochemical risk factors and stent length, the AA genotype remained significantly associated with a reduced prevalence of in-stent restenosis. No relation was evident between the RAGE genotype and established cardiovascular risk factors. In conclusion, the −374AA genotype of the RAGE gene promoter could be associated with a reduced risk of in-stent restenosis after coronary stent implantation.

Emx2 expression levels in NSCs modulate astrogenesis rates by regulating EgfR and Fgf9

Generation of astrocytes within the developing cerebral cortex is a tightly regulated process, initiating at low level in the middle of neuronogenesis and peaking up after its completion. Astrocytic outputs depend on two primary factors: progression of multipotent precursors toward the astroglial lineage and sizing of the astrogenic proliferating pool. The aim of this study was to investigate the role of the Emx2 homeobox gene in the latter process. We addressed this issue by combined gain- and loss-of-function methods, in vivo as well as in primary cultures of cortico-cerebral precursors. We found that Emx2 overexpression in cortico-cerebral stem cells shrinked the proliferating astrogenic pool, resulting in a severe reduction of the astroglial outcome. We showed that this was caused by EgfR and Fgf9 downregulation and that both phenomena originated from exaggerated Bmp signaling and Sox2 repression. Finally, we provided evidence that in vivo temporal progression of Emx2 levels in cortico-cerebral multipotent precursors contributes to confine the bulk of astrogenesis to postnatal life. Emx2 regulation of astrogenesis adds to a number of earlier developmental processes mastered by this gene. It points to Emx2 as a new promising tool for controlling reactive astrogliosis and optimizing cell-based designs for brain repair.

RAGE gene polymorphism in heart failure patients with and without angiographic evidence of significant coronary atherosclerosis

Heart failure (HF) is a multifactorial disorder in which clinical, environmental and genetic components take part. For this reason it is possible that common gene variants could affect development, progression and response to pharmacological therapy. In recent years the role of AGEs in the pathogenesis of cardiovascular diseases has become recognized but little is known about the role of the AGE–RAGE system in heart failure. The aim of the present study was to identify possible relationship between -374 T/A RAGE gene polymorphism with heart failure. The population in this study consists of 386 subjects with HF, selected according to the presence of depressed Left Ventricular Ejection Fraction (LVEF) less than45 percent, and 639 patients with CAD documented at coronary angiography. Within the population with HF there are 228 patients with disease secondary to not ischemic cause and 158 with post-ischemic condition. The sample of AA genotype was significantly lower in patients with post-ischemic HF in respect to HF secondary to non-ischemic causes (pless than0.001). A significant difference between the two groups was also observed regarding the allele frequency. In addition, differences in the allelic and the genotypic frequencies of homozygous genotypes were found between the HF patients free from evidence of coronary significant lesions and patients with at least one hemodynamically significant coronary lesion, both HF and CAD. In patients with at least one vessel compromised the presence of A allele and the homozygous AA genotype were significantly lower than in patients with lesion-free coronary. In conclusion, our research reveals that the -374 T/A polymorphism is related to the genesis of atherosclerotic coronary artery disease but not to its evolution. The protective role of AA genotype in respect to atheromatous disease is therefore confirmed also in the HF population with non-ischemic origin.

The neurotrophin receptor p75NTR is induced on mature myofibres in inflammatory myopathies and promotes myotube survival to inflammatory stress

AIMS

Recent studies propose the neurotrophin receptor p75NTR as a marker for muscle satellite cells and a key regulator of regenerative processes after injury. Here, we investigated the contribution of cellular compartments other than satellite cells and regenerating myofibres to p75NTR signal in diseased skeletal muscle.

METHODS

We checked regulation of p75NTR expression in muscle biopsies from patients with inflammatory myopathies (polymyositis, dermatomyositis and inclusion body myositis), or Becker muscular dystrophy, and in nonmyopathic tissues. Quantitative PCR, immunohistochemistry, immunofluorescence or electron microscopy were used. RNA interference approaches were applied to myotubes to explore p75NTR function.

RESULTS

We found p75NTR transcript and protein upregulation in all inflammatory myopathies but not in dystrophic muscle, suggesting a role for inflammatory mediators in induction of p75NTR expression. In inflamed muscle p75NTR was localized on distinct cell types, including immune cells and mature myofibres. In vitro assays on human myotubes confirmed that inflammatory factors such as IL-1 could induce p75NTR. Finally, RNA interference experiments in differentiated cells showed that, in the absence of p75NTR, myotubes were more susceptible to apoptosis when exposed to inflammatory stimuli.

CONCLUSIONS

Our observations that p75NTR is upregulated on skeletal myofibres in inflammatory myopathies in vivo and promotes resistance to inflammatory mediators in vitro suggest that neurotrophin signalling through p75NTR may mediate a tissue-protective response to inflammation in skeletal myofibres.

Galectin-3 plasma levels and coronary artery disease: a new possible biomarker of acute coronary syndrome

Inflammation plays a key role in atherosclerosis. Galectin-3 is a macrophage- and endothelium-derived mediator actively involved in the regulation of many aspects of inflammatory cell behaviour. The aim of this study is to quantify plasma Galectin-3 in patients with coronary artery disease (CAD) and different clinical manifestation at the moment of observation in order to verify whether Galectin-3 could be a useful biomarker of atherosclerotic state. We enrolled 125 patients affected by CAD, angiographically documented (70 stable, 55 unstable). They underwent accurate examinations and anamnestic data was collected. The most important traditional risk factors, such as age, hypertension, and body mass index, were reported. Plasma Galectin-3 was quantified using an ELISA kit. Unstable patients (n = 55) had a higher plasma Galectin-3 levels in respect to the stable subjects (27.75 ng/mL (19.27-39.09) vs 6.48 ng/ml (4.88-8.83), p&#x003C;0.001. A trend in correlation between plasma Galectin-3 levels and number of vessels compromised seems to be present: CAD patients with three-vessel disease had higher levels of Galectin-3 than patients with one-or two-vessel disease (17.39 ng/ml (10.75-29.82) vs 9.18 ng/ml (5.56-23.22), p= 0.058. The significantly higher plasma Galectin-3 levels in patients with unstable angina in respect to the stable angina confirm the involvement of Galectin-3 in promoting macrophage activation and monocyte attraction. Despite the distribution of CAD in patients with acute and chronic coronary disease being similar, we may hypothesize that Galectin-3 could be a useful biomarker of atherosclerotic plaque and in particular of its destabilization.

Mental status and pain perception during stressor tests in patients with coronary artery disease

Asymptomatic myocardial ischaemia is frequently observed in patients with coronary artery disease (CAD), both during daily life and during stressor tests. Psychological mechanisms seem to be involved in the lack of pain during myocardial ischaemia. The aim of this study was to verify in a selected population of CAD patients whether mental status might influence the pain perception during different stressor tests. The study population contained 73 male patients (mean age 52+/-8 years) with stable angina during daily life, reproducible exercise-induced myocardial ischaemia during ergometric stress test (EST) and angiographically documented CAD. All patients underwent cold pressor test (CPT), mental arithmetic stress test (MST), hyperventilation test (HT) and mental stress in association with cold pressor test (combined test, MST + CPT). During the stressor tests, myocardial ischaemia was induced in 15/73 (21%) patients by CPT, in 18/73 (25%) by MST, in 15/73 (21%) by HT and in 19/73 (26%) by MST + CPT. Out of the patients with stressor test-induced myocardial ischaemia, silent ischaemia was observed in 43/73 (59%) during EST, in 10/15 (67%) during CPT, in 16/18 (89%) during MST, in 7/15 (47%) during HT and in all patients during MST+CPT (100%). Among the ischaemic symptomatic patients during stressor tests, the lowest anginal pain intensity was experienced during MST (4.0+/-2.2) and the highest during EST, both at peak exercise and at the ischaemia threshold (6.6+/-2.9 and 5.9+/-2.7, respectively, p<0.05). During MST, the prevalence of silent ischaemia was higher than was observed during the other tests. All study patients remained asymptomatic when myocardial ischaemia was induced by MST + CPT. Even the intensity of CPT induced hand pain was significantly higher during CPT alone than during MST+CPT. These results confirm that mental status may influence pain modulation.

Water soluble nanoporous nanoparticle for in vivo targeted drug delivery and controlled release in B cells tumor context

Multitasking nanoparticles are gaining great attention for smart drug delivery systems. The exploration of the nano-scale opens new concrete opportunities for revealing new properties and undiscovered cell-particle interactions. Here we present a biodegradable nanoporous silicon nanoparticle that can be successfully employed for in vivo targeted drug delivery and sustained release. The bare nanoporous nanocarriers can be accurately designed and fabricated with an effective control of porosity, surface chemistry and particle size, up to a few nm. The proposed nanoparticles exhibit several remarkable features including high payload, biodegradability, no toxicity, and multiple loading in water without the need of additional chemical reagents at room temperature. The targeting strategy is based on phage display technology that was successfully used to discover cell surface binding peptide for murine B lymphoma A20 cell line. The peptide used in combination with the nanoporous nanoparticles allows an efficient in vivo targeting, a sustained release and a sensible therapeutic effect.

Apelin Plasma Levels Predict Arrhythmia Recurrence in Patients with Persistent Atrial Fibrillation

Low levels of the regulatory peptide apelin have been reported in patients with lone atrial fibrillation (AF). We evaluate the potential utility of assessing apelin plasma levels as a predictor of AF recurrence in individuals presenting for electrical cardioversion. Plasma levels of apelin, brain natriuretic peptide (BNP) and high-sensitivity C-reactive protein were measured in 93 patients, with persistent AF before successful external electrical cardioversion. Significantly lower apelin plasma levels were found in patients with AF recurrence as respect to population with persistence of sinus rhythm during a six months follow-up. The hazard increased with duration of AF, left atrial dimension, BNP concentrations. Subjects with apelin levels below the median had a hazard ratio of 3.1 of arrhythmia recurrence with respect to those with high apelin levels (p< 0.05). A significant difference in BNP levels was found between patients with and without AF recurrence during the follow-up. After adjusting for potential confounders, both BNP and apelin retained their statistical significance as independent predictors of arrhythmia recurrence. Patients with both low apelin and elevated BNP had a worse prognosis compared with those with either low apelin or elevated BNP alone. Low plasma apelin levels before external electrical cardioversion are an independent prognostic factor for arrhythmia recurrence in patients with AF treated with antiarrhythmic drugs. Apelin may be of particular value for the identification of high-risk patients in addition to BNP.

Allergy and multiple sclerosis: a population-based case-control study

BACKGROUND

Epidemiological studies on the association between allergic disorders, T-helper type 2 (Th2) mediated, and multiple sclerosis (MS), a T-helper type 1 (Th1)/Th17-mediated disease, provided conflicting results.

OBJECTIVE

The aim of this study was to further examine the association between allergic disorders and MS.

METHODS

The association between MS and previous medical history of any type of allergy has been investigated in a population-based case-control study conducted in Northern Italy, based on telephone interviews to 423 cases and 643 population controls (refusal rates 3.7% and 9.4%, respectively). Controls were a random sample of the general population.

RESULTS

A history of atopic allergies seems to confer protection against MS (odds ratio [OR], 0.58; 95% confidence interval [CI], 0.38-0.89; P = 0.012). In particular, the prevalence of allergic asthma was 4.9% in people with MS and 12% in control subjects (OR = 0.38; 95% CI 0.22-0.66, P < 0.01). No association was found between MS and nonatopic allergies.

CONCLUSIONS

Our findings are confirmatory of the putative protective effect of Th2-mediated disorders on Th1 immune responses associated with MS. A unifying theory on the mechanisms by which previous history of atopic allergies may modify the risk of MS is still lacking.

Risk of arrhythmia in type I myotonic dystrophy: the role of clinical and genetic variables

OBJECTIVE

To examine the association between the presence of arrhythmia in type 1 myotonic dystrophy (DM1) and clinical-genetic variables, evaluating their role as predictors of the risk of arrhythmia.

METHODS

245 patients with genetically proven DM1 underwent clinical and non-invasive cardiological evaluation. Severity of muscular involvement was assessed according to the 5 point Muscular Disability Rating Score (MDRS). Data were analysed by univariate and multivariate models.

RESULTS

245 patients were examined and cardiac arrhythmias were found in 63 subjects, 40 of whom required a device implant. Statistical analyses revealed that men had more than double the risk of developing arrhythmias compared with women (p = 0.018). Addition of each year of age caused an increased risk of arrhythmia equal to 3% (p = 0.030). Subjects with MDRS 5 had a risk of arrhythmia 12 times higher than patients with MDRS 1-2 (p<0.001). Although all of these variables were significantly associated with cardiac rhythm dysfunction, they had a low sensitivity for the prediction of arrhythmic risk

CONCLUSION

Male sex, age and muscular disability were strongly associated with the development of arrhythmia in DM1. However, all of these variables were weak predictors of arrhythmic risk. These results suggest that other factors may be involved in the development of cardiac conduction abnormalities in DM1.

Apoptosis and aging in mitochondrial morphology mutants of S. cerevisiae

Cell viability during chronological aging and after apoptotic stimuli in some yeast mutants with altered mitochondrial morphology was followed; a function for the corresponding genes in the apoptotic process was assessed. MDM30 and DNM1, the genes encoding an F-box protein and the dynamin-related GTPase, respectively, are involved in triggering aging and apoptosis. In contrast, YME1, encoding a subunit of the mitochondrial inner membrane i-AAA proteinase complex, has a protective role in these processes. FIS1, the mitochondrial fission gene, might play a protective role after an apoptotic insult while it seems to promote cell death in aging cells.

An outcome study on complications using routine ultrasound assistance for internal jugular vein cannulation

BACKGROUND

Ultrasound guidance for central venous cannulation is advised by recent guidelines, but is not being applied in everyday practice. The purpose of this study was to determine the reduction in complications when applying an ultrasound locating device for internal jugular vein catheterization.

METHODS

An observational study was conducted from November 2004 to October 2005 in a tertiary neurosurgical hospital on 300 patients undergoing internal jugular vein cannulation using an ultrasound technique. Patients were not randomized and operators were trained using theoretical and practical courses. Prior to the study, the investigators, who were consultant anaesthesiologists, had to perform at least 20 successful supervised cannulations.

RESULTS

Cannulation was successful in all cases. The incidence of arterial puncture was 2.7%, and multiple venous punctures represented the main minor complication (14%). Bivariate analysis of the overall complications revealed no significant correlation with age group, American Society of Anesthesiologists' (ASA) classification, body mass index, or position and diameter of the vein.

CONCLUSIONS

Ultrasound cannulation of the internal jugular vein minimized complications. These could be avoided when new ultrasound probes and specific needles are introduced.

Approach to respiratory failure in emergency department

OBJECTIVES AND BACKGROUND

The goal of this review is to provide update recommendations that can be used by emergency physicians who provide primary cares to patients with Acute Respiratory Failure (ARF), from the admission to an emergency department through the first 24 to 48 hours of hospitalization. This work wants to address the diagnosis and emergency medical care of ARF and the management of medical complications.

STATE OF THE ART

A lot of statement has been developed for the early management and treatment of ARF; moreover, over the last fifteen years, we have assisted to the rise of a new technique of ventilation, in the Emergency Department: Non Invasive Ventilation. This kind of ventilation was firsthy applied in intensive Care and in Respiratory Care Unit. Randomized controlled clinical trials have showed its usefulness in the early treatment of several forms of ARF, together with medical therapy.