Large field of view aberrations correction with deformable lenses and multi conjugate adaptive optics

Optical microscopes can have limited resolution due to aberrations caused by samples and sample holders. Using deformable mirrors and wavefront sensorless optimization algorithms can correct these aberrations, but the correction is limited to a small area of the field of view. This study presents an adaptive optics method that uses a series of plug-and-play deformable lenses for large field of view wavefront correction. A direct wavefront measurement method using the spinning sub-pupil aberration measurement technique is combined with correction based on the deformable lenses. Experimental results using fluorescence microscopy with a wide field and a light sheet fluorescence microscope show that the proposed method can achieve detection and correction over an extended field of view with a compact transmissive module placed in the detection path of the microscope. This method could improve the resolution and accuracy of imaging in a variety of fields, including biology and materials science.

Large Region of Homozygous (ROH) Identified in Indian Patients with Autosomal Recessive Limb-Girdle Muscular Dystrophy with p.Thr182Pro Variant in SGCB Gene

The sarcoglycanopathies are autosomal recessive limb-girdle muscular dystrophies (LGMDs) caused by the mutations in genes encoding the α, β, γ, and δ proteins which stabilizes the sarcolemma of muscle cells. The clinical phenotype is characterized by progressive proximal muscle weakness with childhood onset. Muscle biopsy findings are diagnostic in confirming dystrophic changes and deficiency of one or more sarcoglycan proteins. In this study, we summarized 1,046 LGMD patients for which a precise diagnosis was identified using targeted sequencing. The most frequent phenotypes identified in the patients are LGMDR1 (19.7%), LGMDR4 (19.0%), LGMDR2 (17.5%), and MMD1 (14.5%). Among the reported genes, each of CAPN3, SGCB, and DYSF variants was reported in more than 10% of our study cohort. The most common variant SGCB p.Thr182Pro was identified in 146 (12.5%) of the LGMD patients, and in 97.9% of these patients, the variant was found to be homozygous. To understand the genetic structure of the patients carrying SGCB p.Thr182Pro, we genotyped 68 LGMD patients using a whole genome microarray. Analysis of the array data identified a large ~1 Mb region of homozygosity (ROH) (chr4:51817441-528499552) suggestive of a shared genomic region overlapping the recurrent missense variant and shared across all 68 patients. Haplotype analysis identified 133 marker haplotypes that were present in ~85.3% of the probands as a double allele and absent in all random controls. We also identified 5 markers (rs1910739, rs6852236, rs13122418, rs13353646, and rs6554360) which were present in a significantly higher proportion in the patients compared to random control set ( $n=128$ ) and the population database. Of note, admixture analysis was suggestive of greater proportion of West Eurasian/European ancestry as compared to random controls. Haplotype analysis and frequency in the population database indicate a probable event of founder effect. Further systematic study is needed to identify the communities and regions where the SGCB p.Thr182Pro variant is observed in higher proportions. After identifying these communities and//or region, a screening program is needed to identify carriers and provide them counselling.

Somatic yolk sac differentiation in tumors of the gynecologic tract: A report of two cases and review of the literature

•Somatic yolk sac tumor differentiation associated with malignant neoplasms is uncommon and associated with poor outcome.•In the gynecologic tract, somatic yolk sac differentiation most often arises in postmenopausal patients.•Somatic yolk sac differentiation shares driver mutations with and likely differentiates from the corresponding carcinoma.•This is the first report of somatic yolk sac differentiation in the gynecologic tract from a non-epithelial malignancy.

Controlled evaLuation of Angiotensin Receptor Blockers for COVID-19 respIraTorY disease (CLARITY): statistical analysis plan for a randomised controlled Bayesian adaptive sample size trial

The CLARITY trial (Controlled evaLuation of Angiotensin Receptor Blockers for COVID-19 respIraTorY disease) is a two-arm, multi-centre, randomised controlled trial being run in India and Australia that investigates the effectiveness of angiotensin receptor blockers in addition to standard care compared to placebo (in Indian sites) with standard care in reducing the duration and severity of lung failure in patients with COVID-19. The trial was designed as a Bayesian adaptive sample size trial with regular planned analyses where pre-specified decision rules will be assessed to determine whether the trial should be stopped due to sufficient evidence of treatment effectiveness or futility. Here, we describe the statistical analysis plan for the trial and define the pre-specified decision rules, including those that could lead to the trial being halted. The primary outcome is clinical status on a 7-point ordinal scale adapted from the WHO Clinical Progression scale assessed at day 14. The primary analysis will follow the intention-to-treat principle. A Bayesian adaptive trial design was selected because there is considerable uncertainty about the extent of potential benefit of this treatment.

Trial registration

ClinicalTrials.gov NCT04394117. Registered on 19 May 2020Clinical Trial Registry of India CTRI/2020/07/026831

Version and revisions

Version 1.0. No revisions.

Aberration measurement and correction on a large field of view in fluorescence microscopy

The aberrations induced by the sample and/or by the sample holder limit the resolution of optical microscopes. Wavefront correction can be achieved using a deformable mirror with wavefront sensorless optimization algorithms but, despite the complexity of these systems, the level of correction is often limited to a small area in the field of view of the microscope. In this work, we present a plug and play module for aberration measurement and correction. The wavefront correction is performed through direct wavefront reconstruction using the spinning-pupil aberration measurement and controlling a deformable lens in closed loop. The lens corrects the aberrations in the center of the field of view, leaving residual aberrations at the margins, that are removed by anisoplanatic deconvolution. We present experimental results obtained in fluorescence microscopy, with a wide field and a light sheet fluorescence microscope. These results indicate that detection and correction over the full field of view can be achieved with a compact transmissive module placed in the detection path of the fluorescence microscope.

Need for pharmacological analgesia after cast immobilisation in children with bone fractures: an observational cross-sectional study

BACKGROUND

Bone fractures are a common reason for children and adolescents to seek evaluation in the ED. Little is known about the pain experienced after cast immobilisation and discharge from the ED and its optimal management. We aimed to investigate the administration of pharmacological analgesia in the first days after cast immobilisation and to identify possible influencing variables.

METHODS

A prospective observational cross-sectional study was conducted at the ED of the children's hospital, Institute for Maternal and Child Health of Trieste, Italy, from October 2019 to June 2020. Patients aged 0-17 years with bone fractures were included. The primary outcome was the administration of analgesia during the 10 days following discharge, while secondary outcomes were the associated variables, including age, gender, fracture type and location, the mean limitation in usual activities and the frequency of re-evaluation at the ED for pain. Data were recorded through a questionnaire, completed by caregivers and collected by the researchers mainly through a telephone interview. The primary endpoint was evaluated as the ratio between the number of children who took at least one analgesic dose and the total enrolled children, while Χ² or Fisher's exact tests were used to assess secondary outcomes.

RESULTS

During the study period, 213 patients, mean age 10 years (IQR: 8-13), were enrolled. Among them, 137 (64.3%) did not take any analgesic during follow-up. Among children who were administered analgesia, 22 (28.9%) received it only on the first day, and 47 (61.8%) for less than 5 days. One hundred and sixty one patients (75.6%) did not report any limitation in usual activities because of pain. The administration of analgesia was not related to the child's age, gender or fracture site. Displaced fractures were associated with significantly more frequent analgesia being taken (OR 5.5, 95% CI 1.4 to 21.0).

CONCLUSION

Although some studies recommend scheduled analgesic treatment after discharge for bone fractures, this study would suggest analgesia on demand in children with non-displaced fractures, limiting scheduled analgesia to children with displaced fractures.

Impact of Dynamical Collapse Models on Inflationary Cosmology

Inflation solves several cosmological problems at the classical and quantum level, with a strong agreement between the theoretical predictions of well-motivated inflationary models and observations. In this Letter, we study the corrections induced by dynamical collapse models, which phenomenologically solve the quantum measurement problem, to the power spectrum of the comoving curvature perturbation during inflation and the radiation-dominated era. We find that the corrections are strongly negligible for the reference values of the collapse parameters.

Gravitational Decoherence and the Possibility of Its Interferometric Detection

We present a general master equation describing the quantum dynamics of a scalar bosonic field interacting with an external weak and stochastic gravitational field. The dynamics predicts decoherence both in position and in energy momentum. We show how the master equation reproduces, thus generalizing, the previous results in the literature by taking appropriate limits. We estimate the effect of gravitational decoherence in atom interferometers, providing also a straightforward way to assess the magnitude of the effect.

Narrowing the Parameter Space of Collapse Models with Ultracold Layered Force Sensors

Despite the unquestionable empirical success of quantum theory, witnessed by the recent uprising of quantum technologies, the debate on how to reconcile the theory with the macroscopic classical world is still open. Spontaneous collapse models are one of the few testable solutions so far proposed. In particular, the continuous spontaneous localization (CSL) model has become subject of intense experimental research. Experiments looking for the universal force noise predicted by CSL in ultrasensitive mechanical resonators have recently set the strongest unambiguous bounds on CSL. Further improving these experiments by direct reduction of mechanical noise is technically challenging. Here, we implement a recently proposed alternative strategy that aims at enhancing the CSL noise by exploiting a multilayer test mass attached on a high quality factor microcantilever. The test mass is specifically designed to enhance the effect of CSL noise at the characteristic length r_{c}=10^{-7}  m. The measurements are in good agreement with pure thermal motion for temperatures down to 100 mK. From the absence of excess noise, we infer a new bound on the collapse rate at the characteristic length r_{c}=10^{-7}  m, which improves over previous mechanical experiments by more than 1 order of magnitude. Our results explicitly challenge a well-motivated region of the CSL parameter space proposed by Adler.

Novel time-resolved camera based on compressed sensing

Time-resolved cameras with high temporal resolution (down to ps) enable a huge set of novel applications ranging from biomedicine and environmental science to material and device characterization. In this work, we propose, and experimentally validate, a novel detection scheme for time-resolved imaging based on a compressed sampling approach. The proposed scheme unifies into a single element all the required operations, i.e. space modulation, space integration and time-resolved detection, paving the way to dramatic cost reduction, performance improvement and ease of use.

The Role of Hemapheresis in Autotransfusion

Hemapheresis is a commonly used technique for single donor procedures of cell and/or plasma collection. In our blood center a new protocol was carried out to study the application of Hemonetics MCS3p to autotransfusion. PES and TAE protocols were applied: 40 patients for ‘each branch and 40 as controls completed the protocol. In the TAE protocol, 2 units of red cell concentrate were collected at day 0, in the PES protocol 300 ml of plasma were added, while in the control group 400 ml of whole blood were collected. Complete blood cell count, clotting parameters, and the EPO level were tested. The two protocols (TAE and PES) prove effective and safe: no significant change was shown for the clotting time and factors, other hematological and plasma values were controlled:; the endogenous EPO doubles its value 24-h after the procedure and the difference compared to controls is highly significant.

Autotransfusion: 15 Years Experience at Rizzoli Orthopaedic Institute

The program of blood saving, result of 15 years of experience, includes predeposit (1977) hemodilution (1979) intra (1984) and postoperative (1985) salvage, careful intra and postoperative bleeding control, use of homologous transfusion only in case of intolerated anaemia even for 7-8g/dl Hb values. The use of autologous compared to homologous transfusion passed from 19% in 1984 to 62% in 1992. In 1992 in the surgical division of the 1st Anaesthesia and Intensive Care unit, 414 patients underwent prosthetic hip and knee surgery, 8% of these patients were homologously transfused.

Plasma Predeposit: The Role of Productive Plasmapheresis

At the Rizzoli Orthopaedic Institute, as part of our autotransfusion program, we have recently had the possibility to introduce plasma predeposit by means of productive plasmapheresis in patients undergoing major orthopaedic surgery, in which bleeding more than 50-60% of circulating blood mass was expected and so a greater quantity of plasma compared to red blood cells was considered necessary. Red cells and fresh frozen plasma predeposits and perioperative blood recovery was sufficient to cover transfusional needs. In our opinion, plasma predepositing by plasmapheresis is indicated in patients with anaemia, cardiopathy and/or vasculopathy, minute constitution.

Blood Saving Program: A Multicenter Italian Experience

To assess the causes of failure in a blood saving program and the consequent need for homologous transfusions during major orthopedic surgery, data were collected from six orthopedic centers where an autotransfusion program was carried out from 1992–1994. The 1,576 (1,016 female and 560 male) patients studied (average age 63.6 ± 10 years) were treated either for total hip prosthesis (1,144 pts) total knee prosthesis (212 pts), plate and screw removal plus hip prosthesis (8 pts), hip revision (cup 48 pts, stem 10 pts, cup plus stem 146 pts) and total knee revision (8 pts). Ninety percent of patients did not undergo homologous transfusions, which was significantly connected to: male sex (8% versus 11.7% p=0.02), younger age (63.2 vs 66.9 years, p=0.0001), higher weight (male 76 vs 70.7 Kg. p = 0.003, female 65.6 vs 61.9 Kg. p = 0.0003); higher baseline Hb (13.9 vs 12.8 gl dl, p = 0.0041), shorter operation time (110 vs 128 minutes, p = 0.0001); use of indobufen for antithromboembolic prophylaxis (indobufen 4.6% vs heparin calcium 15.2% vs low molecular weight heparin 9% p = 0.0001). On the contrary, the factors favoring homologous transfusions were: peripheral anesthesia (spinal and epidural 15.3% vs general 9.3% vs integrated 9.8% p = 0.016), total hip or knee revision, fixation device removal before hip prosthesis, systemic hypertension and coronary heart disease.

Anaesthesia and Autologous Transfusion

The anaesthesiologist plays a central role in co-ordinating the combined application of the various blood saving techniques. In fact, to carry out transfusion therapy correctly, the anaesthesiologist must plan the right number of units of predeposit blood during the first examination, estimate the salvage of intra and post operative blood loss and spread the infusion of the units over the first three days in order to keep the patient in a state of haemodilution. From January 1992 to June 1994 in the department of anaesthesia and the intensive care unit, 980 patients were treated for total joint replacement: 714 total hips (7 after removal of plates and screws) 145 revisions, and 121 total knee prostheses. Basal Hb was 13.4 ± 1.4 g/dl (range 6.7 – 17.9 g/dl). Homologous transfusions were carried out in 6.3% of these patients. The need to use homologous transfusions was negatively influenced by female sex, coronary heart disease (p = 0.005), length of surgery and type of antithromboembolic prophylaxis (indobufen has a significantly low incidence - p = 0.0001 - compared to calcium heparin or low molecular weight heparin).

Practice Pattern of Hemodialysis Vascular Access in Maiduguri, Nigeria

Background

Despite available evidence based recommendations and guidelines there are differences in the preferred type of vascular access in use in different localities and geographical regions. This one center study on the practice pattern of vascular access was carried out in Maiduguri, Nigeria covering a period of the first 5 years of renal care in the area.

Methods

We analysed the dialysis and hospital records of consecutive patients that received hemodialysis in the renal center during the period between January 2000 and December 2004. Data comprised patients' demographics, vascular access used, complications encountered during the treatment period. Clinical and laboratory features of the patients were also recorded and analysed.

Results

The study involved one hundred and seventy-nine patients (M:F=2:1) who suffered kidney failure whose cause was clinically determined to be mainly due to chronic glomerulonephritis, hypertension, obstructive nephropathy and interstitial nephritis. Majority presented as late referrals to the nephrologist. Overall 9 % of the study population used AVFs while 91 % used catheters inserted into the femoral or internal jugular veins.

Conclusion

The use of catheters for vascular access was the practice in the majority of the patients and this is possibly related to the poor survival of the patients on hemodialysis. Socioeconomic circumstances of the patients in turn largely influenced the rate of AVF use.

Exploring synergies between transit investment and dense redevelopment: a scenario analysis in a rapidly urbanizing landscape

Like many urban areas around the world, Durham and Orange counties in North Carolina, USA are experiencing population growth and sprawl that is putting stress on the transportation system. Light rail and denser transit-oriented development are being considered as possible solutions. However, local agencies and stakeholders are concerned the light rail may worsen housing affordability and have questioned whether investment in both light rail and dense redevelopment are necessary to achieve community goals. We developed an integrated system dynamics model to quantitatively explore the outcomes of these land use and transportation options across multiple societal dimensions. The model incorporates feedbacks among the land, transportation, economic, equity, and energy sectors. This paper uses the results of four model scenarios, run between 2000 and 2040, to address two main questions: (1) what role does redevelopment play in capturing the socioeconomic benefits of transit infrastructure investment? And (2) how do redevelopment and light-rail transit interact to affect housing and transportation affordability? We find that transit investment and dense redevelopment combine synergistically to better achieve the goals of the light-rail line, including economic development, mobility, and compact growth. However, housing affordability does worsen in the combined scenario, as transportation-cost savings are not sufficient to offset the rise in housing costs. We emphasize that model users may input their own assumptions to explore the dynamics of alternative scenarios. We demonstrate how spatially-aggregated systems models can complement traditional land use and transportation models in the regional planning process.

A multi-centre audit of excess steroid use in 1176 patients with inflammatory bowel disease

BACKGROUND

Corticosteroids are central to inducing remission in inflammatory bowel disease (IBD) but are ineffective maintenance agents.

AIM

To benchmark steroid usage in British outpatients and assess factors associated with excess exposure.

METHODS

We recorded steroid use in unselected IBD outpatients. Cases meeting criteria for steroid dependency or excess were blind peer reviewed to determine whether steroid prescriptions were avoidable. Associations between steroid use and patient/institutional factors were analysed.

RESULTS

Of 1176 patients, 30% received steroids in the prior 12 months. 14.9% had steroid dependency or excess, which was more common in moderate/severe ulcerative colitis (UC) than Crohn's disease (CD) (42.6% vs 28.1%; P = .027). Steroid dependency or excess was deemed avoidable in 49.1%. The annual incidence of inappropriate steroid excess was 7.1%. Mixed-effects logistic regression analysis revealed independent predictors of inappropriate steroid excess. The odds ratio (OR, 95%CI) for moderate/severe compared to mild/quiescent disease activity was 4.59 (1.53-20.64) for UC and 4.60 (2.21-12.00) for CD. In CD, lower rates of inappropriate steroid excess were found in centres with an IBD multi-disciplinary team (OR 0.62 [0.46-0.91]), whilst dedicated IBD clinics protected against inappropriate steroid excess in UC (OR 0.64, 95% CI 0.21-0.94). The total number of GI trainees was associated with rates of inappropriate steroid excess.

CONCLUSIONS

Steroid dependency or excess occurred in 14.9% of British IBD patients (in 7.1% potentially avoidable). We demonstrated positive effects of service configurations (IBD multi-disciplinary team, dedicated IBD clinics). Routine recording of steroid dependency or excess is feasible and should be considered a quality metric.

Improved Noninterferometric Test of Collapse Models Using Ultracold Cantilevers

Spontaneous collapse models predict that a weak force noise acts on any mechanical system, as a consequence of the collapse of the wave function. Significant upper limits on the collapse rate have been recently inferred from precision mechanical experiments, such as ultracold cantilevers and the space mission LISA Pathfinder. Here, we report new results from an experiment based on a high-Q cantilever cooled to millikelvin temperatures, which is potentially able to improve the current bounds on the continuous spontaneous localization (CSL) model by 1 order of magnitude. High accuracy measurements of the cantilever thermal fluctuations reveal a nonthermal force noise of unknown origin. This excess noise is compatible with the CSL heating predicted by Adler. Several physical mechanisms able to explain the observed noise have been ruled out.

Upper Bounds on Spontaneous Wave-Function Collapse Models Using Millikelvin-Cooled Nanocantilevers

Collapse models predict a tiny violation of energy conservation, as a consequence of the spontaneous collapse of the wave function. This property allows us to set experimental bounds on their parameters. We consider an ultrasoft magnetically tipped nanocantilever cooled to millikelvin temperature. The thermal noise of the cantilever fundamental mode has been accurately estimated in the range 0.03-1 K, and any other excess noise is found to be negligible within the experimental uncertainty. From the measured data and the cantilever geometry, we estimate the upper bound on the continuous spontaneous localization collapse rate in a wide range of the correlation length r_{C}. Our upper bound improves significantly previous constraints for r_{C}>10^{-6}  m, and partially excludes the enhanced collapse rate suggested by Adler. We discuss future improvements.

Donor-specific anti-HLA antibodies after bone-graft transplantation. Impact on a subsequent renal transplantation: a case report

Immunological evaluation by panel-reactive antibody (PRA) and determination of anti-HLA specificity are important phases in the evaluation of patients awaiting kidney transplantation. The main causes of immunization are previous solid organ transplantation, hemotransfusion, and pregnancy. It is also possible that immunogenicity can be triggered by vascularized tissue grafts. Immune induction by cryopreserved bone prostheses is not yet understood. A 19-year-old patient with osteosarcoma had undergone resection of the left proximal tibia with reconstruction using human bone in 1997. The donor HLA typing was as follows: A3, A29 (19); B44 (12), Bw4; DR13 (6), DR7, DR52, DR53. The patient was subsequently enrolled onto the waiting list for cadaveric donor kidney transplantation due to chronic kidney failure caused by cisplatin toxicity. Pretransplantation immunological screening using the complement-dependent cytotoxicity (CDC) technique revealed a PRA of 63%. IgG antibody specificities were detected against class I and class II donor antigens, specifically anti-A3, B44, DR7 antibodies, using flow cytometry (Tepnel Luminex). Further immunological studies using single HLA specificity analysis (LSA Class I degrees -II degrees , Tepnel-Luminex) showed direct antibodies against all donor antigen specificities. This case showed immune induction after the implantation of bone prosthesis in a kidney transplant candidate, underlining the importance of the availability of HLA typing data of donors of a human prosthesis.

[Hemodiafiltration with endogenous reinfusion in chronic inflammation: a possible therapeutic alternative?]

The patients under maintenance haemodialysis (HD) continue to have an unacceptably excess of mortality compared to general population, that may be explained by high prevalence of inflammation that significantly influences the survival of these patients. Indeed, chronic inflammation is very common in HD and it may cause malnutrition and progression of atherosclerotic disease by several pathogenetic mechanisms triggered by pro-inflammatory cytokines. Currently no pharmacological intervention is specifically targeted the idiopathic chronic inflammation. Hemodiafiltration with endogenous reinfusion (HFR) is a dialysis technique, highly biocompatible, that combines three depurative mechanisms: diffusion, convection and absorption. The ultrafiltrate is obtained from convective section of dialyzer (convection). It is regenerated by passing through the adsorbent macro-porous synthetic resin cartridge (absorption) and then it is reinfused into the second section of the filter (diffusion). This resin cartridge is able to absorb cytokines and other uremic toxins, whereas allows to pass nutrients and antioxidants, as amino acids and vitamins, with a consequent decrement of inflammation and oxidative stress. These characteristics suggest the use of HFR in HD patients affected by overt and idiopathic chronic inflammation. In these patients, we observed that the switching from Bic-HD to HFR allowed an improvement of inflammatory as testified by a significant decrement of serum levels of CRP IL-6, IL-1 and TNF- and a significant increase of albumin and pre-albumin. Whether these favorable effects may modify the outcomes of these high-risk patients, needs to be confirmed by studies ad-hoc.

In vitro gene and chromosome characterization of expanded bone marrow mesenchymal stem cells for musculo-skeletal applications

OBJECTIVE

A number of studies have shown the role of expanded Bone Marrow-derived Mesenchymal Stem Cells in the repair and regeneration of musculo-skeletal tissues. The current European regulations define in vitro expanded cells for clinical purposes as substantially manipulated and include them in the class of Advanced-Therapy Medicinal Products to be manufactured in compliance with current Good Manufacturing Practice. Among the characteristics that such cells should display, genomic stability has recently become a major safety concern. The aim of this study is to perform a chromosomal and genetic characterization of Bone Marrow-derived Mesenchymal Stem Cells expanded in compliance with Good Manufacturing Practice for a potential clinical use in orthopaedics.

MATERIALS AND METHODS

Mesenchymal Stem Cells, isolated from bone marrow, were expanded for six weeks in compliance with current Good Manufacturing Practice. DNA profiling analyses were applied to test cross-contamination absence. Genomic stability was evaluated by means of karyotyping, sequencing of TP53, p21/CDKN1A and MDM2 genes and the expression analysis of c-MYC and H-RAS oncogenes, p21/CDKN1A, TP53, p16/CDKN2A, RB1 and p27/CDKN1B tumor suppressor genes and hTERT gene.

RESULTS

The DNA profiling analysis showed a unique genetic profile for each Mesenchymal Stem Cell culture, indicating the absence of cross-contamination. Karyotyping evidentiated some chromosomal abnormalities within the 10% limit set by the Cell Products Working Party review, except for one patient. In all cases, the molecular biology analyses did not revealed DNA point mutations, acquisition or changes in gene expression. hTERT levels were undetectable.

CONCLUSIONS

Cultured Mesenchymal Stem Cells do not seem to be prone to malignant transformation. In fact, although some chromosomal aberrations were found, molecular biology analyses demonstrated that the expansion phase did not induce the acquisition of de novo genetic changes.

Malassezia skin diseases in humans

Although Malassezia yeasts are a part of the normal microflora, under certain conditions they can cause superficial skin infection, such as pityriasis versicolor (PV) and Malassezia folliculitis. Moreover the yeasts of the genus Malassezia have been associated with seborrheic dermatitis and dandruff, atopic dermatitis, psoriasis, and, less commonly, with confluent and reticulated papillomatosis, onychomycosis, and transient acantholytic dermatosis. The study of the clinical role of Malassezia species has been surrounded by controversy due to the relative difficulty in isolation, cultivation, and identification. This review focuses on the clinical, mycologic, and immunologic aspects of the various skin diseases associated with Malassezia. Moreover, since there exists little information about the epidemiology and ecology of Malassezia species in the Italian population and the clinical significance of these species is not fully distinguished, we will report data about a study we carried out. The aim of our study was the isolation and the identification of Malassezia species in PV-affected skin and non-affected skin in patients with PV and in clinically healthy individuals without any Malassezia associated skin disease.

Treatment of severe nail psoriasis with acitretin: an impressive therapeutic result

Nail psoriasis is common in adult psoriatic patients. Although several new drugs have recently been introduced for the treatment of skin psoriasis, treatment of nail psoriasis still remains a challenge. Topical treatments (e.g., corticosteroids, tazarotene, 5-fluorouracil, calcipotriol) are the first line in the management of skin psoriasis. The efficacy of these drugs in nail disease, however, is limited, mainly due to the difficulty in penetrating the nail bed and nail matrix. In cases of nail disease resistant to topical treatment, methotrexate, ciclosporin, acitretin, or biological agents can be used. The present authors introduce a 73-year-old patient affected by impressive psoriatic nail disease involving all her fingernails and toenails treated by acitretin, a traditional systemic treatment. After 2 months of treatment there was a marked improvement. The clinical improvement of the nails was progressive and 6 months later it was stable and satisfactory. The remarkable response to treatment in this case suggests that oral acitretin, in association to urea nail lacquer, might be useful in the management of disabling severe nail psoriasis even in absence of severe cutaneous involvement.