Selective cranial multineuritis in severe COVID-19 pneumonia: two cases and literature review.

OBJECTIVE: To report two cases of cranial multineuritis after severe acute respiratory syndrome caused by coronavirus-2. METHODS: Patients' data were obtained from medical records of the clinical chart of dell'Angelo Hospital, Venice, Italy. RESULTS: The first patient is a 42-year-old male patient who developed, 10 days after the resolution of coronavirus-2 pneumonia and intensive care unit hospitalization with hyperactive delirium, a cranial multineuritis with asymmetric distribution (bilateral hypoglossus involvement and right Claude Bernard Horner syndrome). No albumin-cytologic dissociation was found in cerebrospinal fluid; severe bilateral denervation was detected in hypoglossus nerve, with normal EMG of other cranial muscles, blink reflex, and cerebral magnetic resonance with gadolinium. He presented a striking improvement after intravenous human immunoglobulin therapy. The second case is a 67-year-old male patient who developed a cranial neuritis (left hypoglossus paresis), with dyslalia and deglutition difficulties. He had cerebrospinal fluid abnormalities (albumin-cytologic dissociation), no involvement of ninth and 10th cranial nerves, diffuse hyporeflexia, and brachial diparesis. DISCUSSION: Cranial neuritis is a possible neurological manifestation of coronavirus-2 pneumonia. Etiology is not clear: it is possible a direct injury of the nervous structures by the virus through olfactory nasopharyngeal terminations. However, the presence of albumin-cytological dissociation in one patient, the sparing of the sense of smell, and the response to human immunoglobulin therapy suggests an immune-mediated genesis of the disorder.

Evidence of Large Polarons in Photoemission Band Mapping of the Perovskite Semiconductor CsPbBr_{3}.

Lead-halide perovskite (LHP) semiconductors are emergent optoelectronic materials with outstanding transport properties which are not yet fully understood. We find signatures of large polaron formation in the electronic structure of the inorganic LHP CsPbBr_{3} by means of angle-resolved photoelectron spectroscopy. The experimental valence band dispersion shows a hole effective mass of 0.26±0.02 m_{e}, 50% heavier than the bare mass m_{0}=0.17 m_{e} predicted by density functional theory. Calculations of the electron-phonon coupling indicate that phonon dressing of the carriers mainly occurs via distortions of the Pb-Br bond with a Fröhlich coupling parameter α=1.81. A good agreement with our experimental data is obtained within the Feynman polaron model, validating a viable theoretical method to predict the carrier effective mass of LHPs ab initio.

[Risk of anxiety and depression in nursing students in Rome (Italy)]. / Il rischio di ansia/depressionenegli studenti infermieri è elevato.

The aim of this study was to evaluate the risk of anxiety and depression among student nurses. If not recognized, this risk can adversely affect student health and learning and the quality of patient care. The study was performed through administration of the twelve-item General Health Questionnaire (GHQ-12) to nursing students attending two universities in Rome (Italy). Forty-seven percent of students attending University A and 38% attending University B were found to be at risk. The risk of anxiety and depression was found to be higher in females with respect to males. In both universities, a higher risk was found in those students who were dissatisfied with their academic grades (University A: p £ 0.001, University B: p = 0.03), or with their family's economic situation (A and B £ p = 0.001), and in those who reported stressful events (A: p = 0.036; B: p = 0.02). Regardless of the university, what emerges is a picture of fragile students with female students showing a greater fragility.

Antibacterial and anti-biofilm effects of cathelicidin peptides against pathogens isolated from cystic fibrosis patients.

Six different cathelicidin-derived peptides were compared to tobramycin for antibacterial and anti-biofilm effects against S. aureus, P. aeruginosa, and S. maltophilia strains isolated from cystic fibrosis patients. Overall, SMAP-29, BMAP-28, and BMAP-27 showed relevant antibacterial activity (MIC(50) 4-8µg/ml), and in some cases higher than tobramycin. In contrast, indolicidin, LL-37, and Bac7(1-35) showed no significant antimicrobial activity (MIC(50)>32µg/ml). Killing kinetics experiments showed that in contrast to tobramycin the active cathelicidin peptides exert a rapid bactericidal activity regardless of the species tested. All three peptides significantly reduced biofilm formation by S. maltophilia and P. aeruginosa strains at 1/2× MIC, although at a lower extent than tobramycin. In addition, BMAP-28, as well as tobramycin, was also active against S. aureus biofilm formation. Preformed biofilms were significantly affected by bactericidal SMAP-29, BMAP-27 and BMAP-28 concentrations, although at a lesser extent than tobramycin. Overall, our results indicate the potential of some cathelicidin-derived peptides for the development of novel therapeutic agents for cystic fibrosis lung disease.

Myasthenia gravis: a changing pattern of incidence.

The annual incidence of myasthenia gravis (MG) ranges from 3 to 30 per 1,000,000 people. Since the mid-1980s, an increasing incidence has been reported, mainly due to late-onset MG. Whether the increase was due to population aging, improved diagnosis and case collection, or a true excess of incidence cases is still under debate. We used a complete enumeration approach by reviewing all possible sources of case collection in the province of Ferrara, Italy, to estimate the MG incidence and its temporal trend over the study period (1985-2007). The mean annual age-adjusted incidence of MG was 18 per 1,000,000, without any significant temporal trend. The incidence rates in the period 1985-1990 were 14 both for early and late-onset MG. Thereafter, a significant increase in incidence of late-onset MG (p < 0.05), and a decrease in early onset MG were detected (p < 0.01). These findings were related to nonthymoma MG. The median age at onset of the disease steadily increased over time. A changing pattern of MG incidence with an increase in frequency of late-onset and a decrease of early onset MG was found in the last years, giving a significant shift to older age at onset of the disease. Unknown environmental factors may have driven this change in MG epidemiology.

Activity of antimicrobial peptides in the presence of polysaccharides produced by pulmonary pathogens.

Antimicrobial peptides (AMPs) are secreted in the airway and contribute to initial defence against inhaled pathogens. Infections of the respiratory tract are a major cause of morbidity and mortality in preterm newborns and in patients with cystic fibrosis (CF). In this latter group, the state of chronic lung infection is due to the ability of bacteria to grow as mucoid biofilm, a condition characterised by overproduction and release of polysaccharides (PSs). In this study, we investigate the effect of PSs produced by lung pathogens such as Pseudomonas aeruginosa, Klebsiella pneumoniae and members of the Burkholderia cepacia complex on the antibacterial activity of structurally different peptides. The AMPs tested in this study include the cathelicidin LL-37 and the beta-defensin hBD-3 from humans, both released at the alveolar level, as well as peptides from other mammals, i.e. SMAP-29, PG-1 and Bac7(1-35). Susceptibility assays, time killing and membrane permeabilization kinetics experiments were carried out to establish whether PSs produced by lung pathogens may be involved in the poor defence reaction of infected lungs and thus explain infection persistence. All the PSs investigated inhibited, albeit to a different extent, the antibacterial activity of the peptides tested, suggesting that their presence in the lungs of patients with CF may contribute to the decreased defence response of this district upon infection by PS-producing microorganisms. The results also show that inhibition of the antibacterial activity is not simply due to ionic interaction between the negatively charged PSs and the cationic AMPs, but it also involves other structural features of both interactors.

Multiple sclerosis in the Republic of San Marino: a prevalence and incidence study.

Studies on the distribution of multiple sclerosis (MS) carried out in Southern Europe in the last years have shown a significant increase in the frequency of the disease. A previous descriptive survey in the Republic of San Marino, northern Italian peninsula, published in 1984 established that this area is at high risk for MS. We updated the frequency estimates of the disease by adopting a complete enumeration approach. On 31 December 2005, 50 MS patients (36 women and 14 men) yielded a crude prevalence rate of 166.7 per 100, 000 (95% CI 123.7-220), 235.3 (95% CI 165-327.4) for women and 95.2 (95% CI 52-160) for men. The average incidence from 1990 to 2005 was 7.9 (95% CI 5.3-11.1) per 100,000, 11.7 (95% CI 7.6-17.3) for women and 3.9 (95% CI 1.7-7.7) for men. We did not detect any significant temporal trend over the study period. These results confirm that in San Marino the disease occurs more frequently than that suggested in the past and support the data on MS frequency in continental Italy. The marked increase in MS prevalence ratio is partly due to the increasing survival of patients and the accumulation of new incidence cases owing to the reduction in diagnostic latency for better quality of neurological diagnostic procedures. However, an increased incidence of the disease could be considered.

Multiple sclerosis in the province of Ferrara : evidence for an increasing trend.

BACKGROUND: Epidemiological studies on the distribution of multiple sclerosis (MS) conducted in the Mediterranean area in the last two decades have disclosed a significant increase in frequency of the disease, indicating caution when a latitude-related model of MS is accepted. Previous descriptive surveys in the province of Ferrara, northern Italy, carried out by our own epidemiological research group, have established that this area is at high risk for MS. OBJECTIVE: To confirm the above assumption and to update MS frequency estimates in this area. DESIGN AND SETTING: We conducted a community-based intensive prevalence and incidence study, by adopting a complete enumeration approach. RESULTS: On December 31, 2004, 423 patients (300 women and 123 men) suffering from definite or probable MS (Poser's criteria) living in the province of Ferrara, yielded a crude prevalence rate of 120.93 (95 % CI, 110.05-134.23) per 100,000, 164.26 for women and 73.59 for men. The average incidence from 1990 to 2003 was 4.35 per 100,000 (95 % CI, 3.77-4.99), 5.91 for women and 2.63 for men. The incidence rate,which was relatively stable during the previous 25 years (1965-1989) with a mean rate of 2.3 per 100,000, increased to a value of 3.39 per 100,000 in the period 1990-1994, 4.09 per 100,000 in the period 1995-1999 and 3.84 per 100,000 in the period 2000-2003. CONCLUSIONS: These results confirm that in Ferrara MS occurs more frequently than suggested by the geographic- related distribution model and, based on other recent national surveys, support the view that northern Italy is a high-risk area for the disease. The marked increase in MS prevalence rate, in comparison with previous investigations, is in part due to the increasing survival of patients as a result of improved supportive care and the accumulation of new incidence cases owing to the reduction in diagnostic latency for better quality of neurological diagnostic procedures. The incidence in the province of Ferrara was found to slowly change with an incremental trend,which cannot only be attributed to improvements in diagnostic ability. Environmental risk factors in genetically predisposed people over time could be considered.

Continuous subcutaneous insulin infusion (CSII) in the Veneto region: efficacy, acceptability and quality of life.

AIM: To study the effect of continuous subcutaneous insulin infusion (CSII) on metabolic control and well-being in patients with Type 1 diabetes. METHODS: Efficacy, safety and interference with everyday life associated with CSII were studied retrospectively in 138 diabetic patients from the Veneto region treated for 7.4 +/- 0.4 years. RESULTS: Glycosylated haemoglobin decreased during the first year of CSII from 9.3 +/- 0.2% to 7.9 +/- 0.1% (P < 0.0001), and then remained unchanged. Serious hypoglycaemia decreased from 0.31 +/- 0.07/year to 0.09 +/- 0.02/year (P < 0.003), as did ketoacidosis (from 0.41 +/- 0.12/year to 0.11 +/- 0.03/year, P < 0.013). During the first year of therapy daily insulin requirement decreased from 49 +/- 1 to 42 +/- 2 U/day (P < 0.0001) and did not change thereafter. The number of out-patient consultations and hospital admissions per year also decreased significantly. CSII was associated with a progressive increase of body weight (P < 0.05) and with 0.2 +/- 0.04 infections/patient per year at the infusion site. Infection was rated as mild in 72%, moderate in 18%, severe in 10%. Patients reported that CSII improved metabolic control (71%), sense of well-being (41%), and allowed more freedom (40%). Quality of life, assessed using the DQOL, after 7 years of CSII was rated as good by patients (score of 73.0 +/- 1.8 on a scale from 0 to 100). CONCLUSIONS: This retrospective analysis suggests that CSII improves metabolic control in Type 1 diabetic patients, reduces hypoglycaemic and ketoacidotic events, is well accepted, allows a good quality of life and decreases out-patient consultations and hospital admissions.

Preparation of an antibody recognizing both human and rodent MRP1.

Based on the high level of identity among human, mouse, and rat MRP1 protein sequence, we produced a specific polyclonal antibody (MRP1-A23) against a synthetic polypeptide covering the C-terminus of the human protein. Western blot analysis showed a reactivity against human MRP1 similar to that obtained with the monoclonal QCRL1 antibody. Differently from other available antibodies against human MPR1, MRP1-A23 also detected both rat and mouse MRP1. No cross-reactivity was observed with either human or mouse MRP2 while MRP1-A23 weakly cross-reacted with rat MRP2 in the protein region ranging from 1512 to 1533 amino acids. These data indicate that MRP1-A23 allows specific MRP1 detection in both human and rodent tissues and may provide an important tool in the study of MRP1 expression and function in both experimental and clinical materials.

Anti-microbial activity and cell binding are controlled by sequence determinants in the anti-microbial peptide PR-39.

PR-39 is a member of the proline-rich group of cathelicidin peptides, a class of anti-microbial peptides found in skin and in leukocytes. In addition to their innate defense function, these proline-rich peptides influence a number of mammalian cell processes, including inflammation, development, differentiation, and metastatic transformation. To characterize the mechanism further, through which proline-rich cathelicidin peptides may exert their numerous effects, we altered various conserved peptide sequence motifs using a biologically active fragment of PR-39 [PR-39(15)] as the template: We altered the N-terminal charge of its SH3 binding motif, substituted tryptophan for a conserved intervening leucine, and modified a proline-arginine stretch (residues 10-13). These peptide variants were tested for binding known targets of PR-39 and for biologic activity in mammalian and bacterial systems. We found that the N-terminal arginines are crucial for protein binding and that modification in this domain results in loss of affinity and specificity in binding to generalized and SH3-containing targets. The N-terminal charged residues are also required for NIH 3T3 syndecan induction and anti-microbial activity. In addition, modification of more C-terminal residues eliminates anti-bacterial activity while having less of an effect on peptide interactions in mammalian cell assays. This study shows that the presence of a charged N-terminus is important for peptide activity in both mammalian and bacterial systems whereas the C-terminal alterations of PR-39(15) more definitively affect anti-bacterial activity.

Structural and functional analysis of horse cathelicidin peptides.

Cathelicidin-derived antimicrobial peptides are a component of the peptide-based host defense of neutrophils and epithelia, with a widespread distribution in mammals. We recently reported the cDNA sequences of three putative horse myeloid cathelicidins, named eCATH-1, -2, and -3. A Western analysis was performed to investigate their presence in neutrophils and processing to mature peptides. eCATH-2 and eCATH-3, but not eCATH-1, were found to be present in uncleaved forms in horse neutrophils. The corresponding mature peptides were detected in inflammatory sites, suggesting that processing of the propeptides takes place upon neutrophil activation. A functional characterization was then performed with synthetic eCATH peptides. Circular dichroism measurements indicated an amphipathic alpha-helical conformation of these peptides in an anisotropic environment, and in vitro assays revealed a potent activity and a broad spectrum of antimicrobial activity for eCATH-1 and a somewhat more restricted spectrum of activity for eCATH-2. Conversely, a strong dependence on salt concentration was observed when the activity of eCATH-3 was tested. This peptide efficiently killed bacteria and some fungal species, i.e., Cryptococcus neoformans and Rhodotorula rubra, in low-ionic-strength media, but the activity was inhibited in the presence of physiological salt medium. This behavior could be modified by modulating the amphipathicity of the molecule. In fact, the synthetic analogue LLK-eCATH-3, with a slightly modified sequence that increases the hydrophobic moment of the peptide, displayed a potent activity in physiological salt medium against the strains resistant to eCATH-3 under these conditions.

Structural features and biological activities of the cathelicidin-derived antimicrobial peptides.

Cathelicidins are a numerous group of mammalian proteins that carry diverse antimicrobial peptides at the C-terminus of a highly conserved preproregion. These peptides, which become active when released from the proregion, display a remarkable variety of sizes, sequences, and structures, and in fact comprise representatives of all the structural groups in which the known antimicrobial peptides have been classified. Most of the cathelicidin-derived peptides exert a broad spectrum and potent antimicrobial activity and also bind to lipopolysaccharide and neutralize its effects. In addition, some of them have recently been shown to exert other activities and might participate in host defense also by virtue of their ability to induce expression of molecules involved in a variety of biological processes. This review is aimed at providing a general overview of the cathelicidins and of the peptides derived therefrom, with emphasis on aspects such as structure, biological activities in vitro and in vivo, and structure/activity relationship studies.

SMAP-29: a potent antibacterial and antifungal peptide from sheep leukocytes.

SMAP-29 is a cathelicidin-derived peptide deduced from sheep myeloid mRNA. The C-terminally amidated form of this peptide was chemically synthesized and shown to exert a potent antimicrobial activity. Antibiotic-resistant clinical isolates highly susceptible to this peptide include MRSA and VREF isolates, that are a major worldwide problem, and mucoid Pseudomonas aeruginosa associated with chronic respiratory inflammation in CF patients. In addition, SMAP-29 is also active against fungi, including Cryptococcus neoformans isolated from immunocompromised patients. SMAP-29 causes significant morphological alterations of the bacterial surfaces, as shown by scanning electron microscopy, and is also hemolytic against human, but not sheep erythrocytes. Its potent antimicrobial activity suggests that this peptide is an excellent candidate as a lead compound for the development of novel antiinfective agents.

Biological characterization of a novel mammalian antimicrobial peptide.

A putative antimicrobial peptide of 34 residues was recently deduced from a bovine cathelicidin gene sequence and named BMAP-34. A peptide based on the deduced sequence was chemically synthesized and used to study the localization, structure and biological activities of BMAP-34. A Western blot analysis using antibodies raised to the synthetic peptide showed that BMAP-34 is stored as proform in the cytoplasmic granules of bovine neutrophils. CD spectroscopy indicates that the peptide assumes an amphipathic alpha-helical conformation, as also predicted by secondary structure analysis. The peptide exerts a broad spectrum antimicrobial activity against both Gram-negative and Gram-positive organisms, and is not active against eukaryotic cells. When tested on Escherichia coli ML-35, the kinetics of bacterial killing and of inner membrane permeabilization are slower than those observed for other alpha-helical peptides derived from cathelicidins.

Cytotoxicity and apoptosis mediated by two peptides of innate immunity.

Antimicrobial peptides are present in a wide range of species, from protozoa to man, as effector molecules of innate immunity. Several bovine precursors of antimicrobial peptides have recently been identified, as deduced from cDNA, and assigned to the cathelicidin family. Two of these are the proforms of the antimicrobial peptides BMAP-27 and BMAP-28, which share a similar amino acid sequence, structural conformation, and toxic activity toward several bacterial and fungal strains. Here we report that they are cytotoxic to human tumor cells and normal proliferating, but not resting, lymphocytes at concentrations comparable to those microbiocidal. This effect is primarily due to damage of plasma membrane integrity. A more detailed investigation of the U937 cell line revealed that a Ca2+ influx into the cytosol occurs in the early steps of permeabilization. The perturbation of the membrane structure and the Ca2+ influx are followed by programmed death. A similar apoptosis inducing effect is also observed on in vitro activated human lymphocytes.

Cloning and analysis of a transcript derived from two contiguous genes of the cathelicidin family.

Bac4 is a bovine cathelicidin gene contiguous to another member of this family named Bac7. Although mutations in the sequence suggested that Bac4 gene might be non-functional, primers based on Bac4 specific sequences allowed amplification of a 900 bp cDNA. The transcript comprises the sequences of exons 1, 2 and 3 of Bac7, and of exons 2, 3 and 4 of Bac4 gene and may result from a weak termination control of the transcription of the upstream Bac7 gene.

Identification of CRAMP, a cathelin-related antimicrobial peptide expressed in the embryonic and adult mouse.

Cathelicidins are the precursors of potent antimicrobial peptides that have been identified in several mammalian species. Prior work has suggested that members of this gene family can participate in host defense through their antimicrobial effects and activate mesenchymal cells during wound repair. To permit further study of these proteins a reverse transcriptase-polymerase chain reaction approach was used to identify potential mouse homologs. A full-length 562-base pair cDNA clone was obtained encoding an NH2-terminal prepro domain homologous to other cathelicidins and a unique COOH-terminal peptide. This gene, named Cramp for cathelin-related antimicrobial peptide, was mapped to chromosome 9 at a region of conserved synteny to which genes for cathelicidins have been mapped in pig and man. Northern blot analysis detected a 1-kilobase transcript that was expressed in adult bone marrow and during embryogenesis as early as E12, the earliest stage of blood development. Reverse transcriptase-polymerase chain reaction also detected CRAMP expression in adult testis, spleen, stomach, and intestine but not in brain, liver, heart, or skeletal muscle. To evaluate further the expression and function of CRAMP, a peptide corresponding to the predicted COOH-terminal region was synthesized. CD spectral analysis showed that CRAMP will form an amphipathic alpha-helix similar to other antimicrobial peptides. Functional studies showed CRAMP to be a potent antibiotic against Gram-negative bacteria by inhibiting growth of a variety of bacterial strains (minimum inhibitory concentrations 0.5-8.0 microM) and by permeabilizing the inner membrane of Escherichia coli directly at 1 microM. Antiserum against CRAMP revealed abundant expression in myeloid precursors and neutrophils. Thus, CRAMP represents the first antibiotic peptide found in cells of myeloid lineage in the mouse. These data suggest that inflammatory cells in the mouse can use a nonoxidative mechanism for microbial killing and permit use of the mouse to study the role such peptides play in host defense and wound repair.