Rate-induced tracking for concave or d-concave transitions in a time-dependent environment with application in ecology.

This paper investigates biological models that represent the transition equation from a system in the past to a system in the future. It is shown that finite-time Lyapunov exponents calculated along a locally pullback attractive solution are efficient indicators (early-warning signals) of the presence of a tipping point. Precise time-dependent transitions with concave or d-concave variation in the state variable giving rise to scenarios of rate-induced tracking are shown. They are classified depending on the internal dynamics of the set of bounded solutions. Based on this classification, some representative features of these models are investigated by means of a careful numerical analysis.

Electric and magnetic fields do not modify the biochemical properties of FRTL-5 cells.

BACKGROUND: Electric and magnetic fields (EMF) might be involved in human disease and numerous research and scientific reviews have been conducted to address this question. In particular thyroid structural and functional alterations caused by various forms of non-ionizing radiation have been described. AIM: The aim of this study was to analyze the possible effects of EMF on thyroid, in particular we analyzed the effects caused by a GSM (Global System for Mobile Communications) signal (900 MHz) on cultured thyroid cells (FRTL- 5). MATERIAL AND METHODS: The experimental setup was designed in order to expose samples to a radiofrequency wave in well-controlled conditions. We used the FRTL-5 cell line, an epithelial monoclonal continuous cell line derived from Fisher rat thyroid tissue growing as monolayer, expressing the TSH receptor and the sodium-iodide symporter (NIS). FRTL-5 were subsequently irradiate for 24, 48, and 96 h with EMF (800-900 MHz, power-frequency of mobile communication systems) and iodide uptake and cAMP production were measured. RESULTS: The irradiation of cells with EMF at 900 Mhz for 24, 48, and 96 h did not influence the level of cAMP production and was not able to modify iodide accumulation in FRTL- 5 cells with respect to basal conditions. CONCLUSIONS: In conclusion, EMF do not seem to be able to interfere with the biochemical properties of FRTL-5 cells in vitro.

The XLMR gene ACSL4 plays a role in dendritic spine architecture.

ACSL4 is a gene involved in non-syndromic X-linked mental retardation. It encodes for a ubiquitous protein that adds coenzyme A to long-chain fatty acids, with a high substrate preference for arachidonic acid. It presents also a brain-specific isoform deriving from an alternative splicing and containing 41 additional N-terminal amino acids. To start to unravelling the link between ACSL4 and mental retardation, we have performed molecular and cell biological studies. By retro-transcription polymerase chain reaction analyses we identified a new transcript with a shorter 5'-UTR region. By immunofluorescence microscopy in embryonic rat hippocampal neurons we report that ACSL4 is associated preferentially to endoplasmic reticulum tubules. ACSL4 knockdown by siRNAs in hippocampal neurons indicated that this protein is largely dispensable for these cells' gross architectural features (i.e. axonal and dendritic formation and final length) yet it is required for the presence of normal spines. In fact, reduced levels of ACSL4 led to a significant reduction in dendritic spine density and an alteration in spine/filopodia distribution. The possible mechanisms behind this phenotype are discussed.

Quality of Life, Behaviour and Attitudes towards Actinic Keratosis in Spain: The PIQA Study. / Calidad de vida, comportamiento y actitudes hacia la queratosis actínica en España: estudio PIQA.

OBJECTIVE: This study was aimed to examine patients' knowledge, behaviours and attitudes regarding actinic keratosis (AK) lesions and the impact of the disease on patients' quality of life (QoL). METHODS: Observational study of patients with AK lesions in Spain. QoL was evaluated with the validated version of Spanish AKQoL questionnaire. Skin self-examination, sun-exposure, habits and attitudes towards AK's treatment were recorded using different questionnaires. The adherence was assessed by means of the Morisky-Green test. Among other variables, QoL and adherence to treatment were compared by using Pearson's χ2 test and one-way ANOVA tests. Inferential analysis regarding such factors and length of treatment were also performed. RESULTS: A total of 1240 patients (73.6 [10.5] years old) were recruited. Overall, patients that showed higher levels of concern were also showed a higher impairment on QoL. AK had greater effects on women's QoL and those who performed skin self-examination, think that AK is a disease and/or believe that moisturizers can prevent skin aging (P<.05). Adherence and length of treatment were strongly related, since patients with treatments intended for <1week were more likely to show good adherence and complete remission of AK (Odds Ratio [95%CI]: 6.25 [4.55-8.33] and 2.63 [1.96-3.45]), respectively). CONCLUSIONS: Concerns due to AK are mainly related to sex and to the consideration of AK as a disease. More concerned patients tend to have lower QoL and good adherence to treatment. Short length of treatment was associated with better adherence and complete remission of AK lesions.

The Italian XLMR bank: a clinical and molecular database.

Mental retardation (MR) is a nonprogressive condition characterized by a significant impairment of intellectual capabilities with deficit of cognitive and adaptive functioning and onset before 18 years. Mental retardation occurs in about 2 to 3% of the general population and it is estimated that 25 to 35% of the cases may be due to genetic causes. Among these "genetic" MR, 25 to 30% are probably due to mutations in a gene on the X chromosome (X-linked mental retardation, XLMR). Given the genetic heterogeneity of XLMR, the availability of a considerable number of patients with accurate phenotypic classification is a crucial factor for research. The X-linked Mental Retardation Italian Network, which has been active since 2003, has collected detailed clinical information and biological samples from a vast number of MR patients. Collected samples and clinical information are inserted within the XLMR bank, a comprehensive molecular and clinical web-based database available at the address http://xlmr.unisi.it. The database is organized in three distinct parts. Part I and II contain several electronic schedules to register information on the family, the phenotypic description, the photographs, and a 20 sec movie of the patient. Part III allows the registration of molecular analyses performed on each case; samples and clinical data are usable via password-restricted access. Clinical and molecular centers interested in joining the network may request a password by simply contacting the Medical Genetics of the University of Siena. The XLMR bank is an innovative biological database that allows the collection of molecular and clinical data, combines descriptive and iconographic resources, and represents a fundamental tool for researchers in the field of mental retardation.

A 2.6 Mb deletion of 6q24.3-25.1 in a patient with growth failure, cardiac septal defect, thin upperlip and asymmetric dysmorphic ears.

We report a female patient with neurodevelopmental delay and peculiar facial features. She has postnatal growth failure and an atrial septal defect. Patent duct arteriosis and tricuspidal insufficiency were also noted at birth. Characteristic facial features include medial flare eyebrows, dysmorphic helix of the right ear, cupshaped left ear, anteverted nares, long and smooth philtrum, thin upper lip, high vaulted palate. Array-CGH analysis demonstrated the presence of a 2.6 Mb deletion in 6q24.3-25.1. The phenotypic features of this case are very similar to those previously reported in a patient with a 7Mb overlapping deletion, pointing to a specific new syndrome. Twenty-two genes are present in the common critical deleted region. Among them, there is the PPP1R14C gene that encodes for KEPI, a PKC-potentiated inhibitory protein for type-1 Ser/Thr protein phosphatase. Its selective distribution in brain and heart well correlates with developmental delay and cardiac anomalies observed in the patient.

CDKL5/STK9 is mutated in Rett syndrome variant with infantile spasms.

BACKGROUND: Rett syndrome is a severe neurodevelopmental disorder, almost exclusively affecting females and characterised by a wide spectrum of clinical manifestations. Both the classic form and preserved speech variant of Rett syndrome are due to mutations in the MECP2 gene. Several other variants of Rett syndrome have been described. In 1985, Hanefeld described a variant with the early appearance of convulsions. In this variant, the normal perinatal period is soon followed by the appearance of seizures, usually infantile spasms. We have observed two patients with signs of Rett syndrome showing acquired microcephaly and stereotypic midline hand movements. The disease started with generalised convulsions and myoclonic fits at 1.5 months in the first patient and with spasms at 10 days in the other, suggesting a diagnosis of the Hanefeld variant. In these patients, MECP2 point mutations and gross rearrangements were excluded by denaturing high performance liquid chromatography and real time quantitative PCR. The ARX and CDKL5 genes have been associated with West syndrome (infantile spasms, hypsarrhythmia, and mental retardation). METHODS: Based on the clinical overlap between the Hanefeld variant and West syndrome, we analysed ARX and CDKL5 in the two girls. RESULTS: We found frameshift deletions in CDKL5 in both patients; one in exon 5 (c.163_166delGAAA) and the other in exon 18 (c.2635_2636delCT). CDKL5 was then analysed in 19 classic Rett and 15 preserved speech variant patients, all MECP2 negative, but no mutations were found. CONCLUSION: Our results show that CDKL5 is responsible for a rare variant of Rett syndrome characterised by early development of convulsions, usually of the spasm type.

A third MRX family (MRX68) is the result of mutation in the long chain fatty acid-CoA ligase 4 (FACL4) gene: proposal of a rapid enzymatic assay for screening mentally retarded patients.

BACKGROUND: The gene encoding fatty acid CoA ligase 4 (FACL4) is mutated in families with non-specific X linked mental retardation (MRX) and is responsible for cognitive impairment in the contiguous gene syndrome ATS-MR (Alport syndrome and mental retardation), mapped to Xq22.3. This finding makes this gene a good candidate for other mental retardation disorders mapping in this region. METHODS: We have screened the FACL4 gene in eight families, two MRX and six syndromic X linked mental retardation (MRXS), mapping in a large interval encompassing Xq22.3. RESULTS: We have found a missense mutation in MRX68. The mutation (c.1001C>T in the brain isoform) cosegregates with the disease and changes a highly conserved proline into a leucine (p.P375L) in the first luciferase domain, which markedly reduces the enzymatic activity. Furthermore, all heterozygous females showed completely skewed X inactivation in blood leucocytes, as happens in all reported females with other FACL4 point mutations or deletions. CONCLUSIONS: Since the FACL4 gene is highly expressed in brain, where it encodes a brain specific isoform, and is located in hippocampal and cerebellar neurones, a role for this gene in cognitive processes can be expected. Here we report the third MRX family with a FACL4 mutation and describe the development of a rapid enzymatic assay on peripheral blood that we propose as a sensitive, robust, and efficient diagnostic tool in mentally retarded males.

Analgesic effect of He-Ne (632.8 nm) low-level laser therapy on acute inflammatory pain.

OBJECTIVE: The aim of this study was to evaluate the analgesic effect of the low level laser therapy (LLLT) with a He-Ne laser on acute inflammatory pain, verifying the contribution of the peripheral opioid receptors and the action of LLLT on the hyperalgesia produced by the release of hyperalgesic mediators of inflammation. BACKGROUND DATA: All analgesic drugs have undesired effects. Because of that, other therapies are being investigated for treatment of the inflammatory pain. Among those, LLLT seems to be very promising. MATERIAL AND METHODS: Male Wistar rats were used. Three complementary experiments were done. (1) The inflammatory reaction was induced by the injection of carrageenin into one of the hind paws. Pain threshold and volume increase of the edema were measured by a pressure gauge and plethysmography, respectively. (2) The involvement of peripheral opioid receptors on the analgesic effect of the laser was evaluated by simultaneous injection of carrageenin and naloxone into one hind paw. (3) Hyperalgesia was induced by injecting PGE2 for the study of the effect of the laser on the sensitization increase of nociceptors. A He-Ne laser (632.8 nm) of 2.5 J/cm2 was used for irradiation. RESULTS: We found that He-Ne stimulation increased the pain threshold by a factor between 68% and 95% depending on the injected drug. We also observed a 54% reduction on the volume increase of the edema when it was irradiated. CONCLUSION: He-Ne LLLT inhibits the sensitization increase of nociceptors on the inflammatory process. The analgesic effect seems to involve hyperalgesic mediators instead of peripheral opioid receptors.

[Clinical and genetic features of the Alport 'syndromes']. / Le 'sindromi' di Alport: dalla clinica alla genetica.

Alport syndrome (ATS) is a clinically and genetically heterogeneous progressive nephropathy often associated with deafness and/or ocular lesions. The histological aspect is characterized by thinning, thickening and splitting of the glomerular basement membrane (GBM). Alport syndrome is caused by mutations in COL4A3 gene (type IV collagen, alfa-3 chain), or COL4A4 gene (type IV collagen, alfa-4 chain) or COL4A5 gene (type IV collagen, alfa-5 chain) genes. Alport syndrome accounts for 1-2% of renal failure cases in Europe, and for 2-3% of transplanted patients in United States. This review focuses on the three types of Alport syndrome which differ in the clinical progression and in the mode of inheritance. The common X-linked form is caused by mutations in the COL4A5 gene and it accounts for 85% of cases. The autosomal dominant and the autosomal recessive forms are caused by mutations in either COL4A3 or COL4A4 genes. The autosomal recessive form which is responsible for the 10-15% of Alport cases, has been known since several years. On the contrary, the autosomal dominant form has only recently been identified in some families. Furthermore, this review will focus on the difficulties encountered during the genetic counselling related to the differential diagnosis between Alport syndrome and Thin Basement Membrane Disease (TBMD). We will report direct experiences of our group showing the difficulties to give an exact prognosis and a correct recurrence risk to the family.

Preserved speech variant is allelic of classic Rett syndrome.

Rett syndrome is a neurological disorder affecting predominantly females with regression loss of speech and purposeful hand use, after a few months of almost normal development. Postnatal microcephaly, hand dispraxia, stereotypic 'hand-washing' activities, ataxia, and abnormal breathing are among its most characteristic features. Another aspect of this disorder is growth failure. The preserved speech variant (PSV) shares with Rett syndrome the same course and the stereotypic hand-washing activities but it differs in that patients typically recover some degree of speech and hand use and usually do not show growth failure. Progressive scoliosis, epilepsy and other minor handicaps, usually present in Rett syndrome, are rare in the preserved speech variant. Here we explore the spectrum of mutations affecting the MECP2 gene in a group of 25 classic Rett syndrome girls and in three patients with the preserved speech variant. Among the Rett syndrome group, two novel mutational hot spots (R270X and R294X), four novel mutations, two novel small deletions, as well as the previously reported 806delG, R168X and R255X mutations, were identified in 20/25 patients. Of note, among the preserved speech variants, two patients carry deletions of 41 bp and 44 bp each, which are strikingly similar to those observed in classic Rett syndrome. Our results confirm the presence of mutational hot spots in MECP2, broaden the spectrum of mutations, pinpoint additional mutational hot spots and establish that the preserved speech variant is indeed allelic of the classic form. Phenotype variability is only partially dependent on the kind of MECP2 mutation and other mechanisms such as skewed X-inactivation, and/or modifier gene effects should be investigated to explain the variable recovery in speech and hand use.

Preserved speech variants of the Rett syndrome: molecular and clinical analysis.

Mutations in the MECP2 gene cause the severe neurodevelopmental disorder called Rett syndrome. Preliminary evidence suggests that MECP2 may be involved in a broader phenotype than classical Rett syndrome including preserved speech variants (PSV). Here we report clinical and mutation analysis of 18 PSV patients. Ten of them had a MECP2 mutation (55%). The clinical features of these girls have been characterized and two subgroups defined. All of them had slow recovery of verbal and praxic abilities, evident autistic behavior, and normal head circumference. Six were overweight, often obese, had kyphosis, coarse face, and mental age of two-to-three years, and were able to speak in sentences; four had normal weight, mental age not beyond one-to-two years, and spoke in single words and two-word phrases. The course of the disorder was in stages as in classic Rett syndrome. Hand-washing was present in the first years of life but often subsequently disappeared. Significantly, all mutations found in PSV are either missense or late truncating mutations. In particular, we did not find the four early truncating hot spots: R168X, R255X, R270X, R294X. These results suggest that early truncating mutations lead to a poor prognosis (classic Rett), while late truncating and missense mutations lead either to classic Rett or PSV. We hypothesize that a missense or late truncating mutation is necessary but not sufficient to produce a PSV, based on the presence of one (or more) modifier genes whose product may interact in a epistatic manner with MeCP2 protein.

High-field, multifrequency EPR spectroscopy using whispering gallery dielectric resonators.

High-field/high frequency EPR spectroscopy measurements are shown. Experiments were carried out at 240- and 316-GHz frequencies. The employed apparatus uses a novel combination of far infrared molecular lasers and of probehead exploiting dielectric resonators working in the whispering gallery modes. This approach constitutes a relatively simple method of multifrequency EPR spectroscopy and opens appealing perspectives in high-sensitivity EPR spectroscopy up to the THz regime.

Hyperalgesia induced by Asp49 and Lys49 phospholipases A2 from Bothrops asper snake venom: pharmacological mediation and molecular determinants.

The ability of Lys49 and Asp49 phospholipases A(2) (PLA(2)), from Bothrops asper snake venom, to cause hyperalgesia was investigated in rats, using the paw pressure test. Intraplantar injection of both toxins (5-20 micro g/paw) caused hyperalgesia, which peaked 1h after injections. Incubation of both proteins with heparin, prior to their injection, partially reduced this response. Chemical modification of Asp49 PLA(2) with p-bromophenacyl bromide (p-BPB), which abrogates its PLA(2) activity, also abolished hyperalgesia. Intraplantar injection of a synthetic peptide corresponding to the C-terminal sequence 115-129 of Lys49 PLA(2), caused hyperalgesia of similar time course, but varying magnitude, than that induced by the native protein. In contrast, a homologous peptide derived from the Asp49 PLA(2) did not show any nociceptive effect. Hyperalgesia induced by both PLA(2)s was blocked by the histamine and serotonin receptor antagonists promethazine and methysergide, respectively, by the bradykinin B(2) receptor antagonist HOE 140 and by antibodies to tumor necrosis factor alfa (TNFalpha) and interleukin 1 (IL-1). Pretreatment with guanethidine, atenolol, prazosin and yohimbine, inhibitors of sympathomimetic amines, or with indomethacin, inhibitor of the cyclo-oxygenase pathway, reduced Lys49 PLA(2)-induced hyperalgesia without interfering with the nociceptive activity of Asp49 PLA(2). The hyperalgesic response to both myotoxins was not modified by pretreatment with celecoxib, an inhibitor of the cyclo-oxygenase type II, by zileuton, an inhibitor of the lipoxygenase pathway or by N(g)-methyl-L-arginine (LNMMA), an inhibitor of nitric oxide synthase. These results suggest that Asp49 and Lys49 PLA(2)s are important hyperalgesic components of B. asper venom, and that Lys49 and Asp49 PLA(2)s exert their algogenic actions through different molecular mechanisms.

Detection of the human T lymphocyte soluble receptor for sheep erythrocytes by double gel diffusion.

An anti-human T lymphocyte serum specific to the membrane receptor for sheep erythrocytes (E) was produced by immunizing sheep with the autologous E-soluble E receptor complex. The soluble E receptor (RS) was obtained by heating human lymphocytes at 45 degrees C for 1 h. The anti-RS serum reacted by double gel diffusion with preparations containing Rs such as the supernatant of heated peripheral lymphocytes (SHPL), the supernatant of heated spleen lymphocytes (SHSL) and concentrated normal human serum (NHSc), producing a single precipitation line with each preparation. The pattern obtained was that of total identify. The reactivity of SHPL, SHSL or NHSc was abolished by previous absorption with 2-aminoethylisothiouronium bromide-treated E. Anti-RS serum also did not react with the supernatant of heated cells such as HeLa cells and polymorphonuclear leukocytes which do not have exposed E receptors.

Transfer of cell-mediated immunity to HIV antigens in vivo to a Cebus monkey and in vitro to human lymphocytes with xenogeneic immune RNA.

1. Immune RNA (iRNA) was extracted from the spleen of a sheep immunized with human immunodeficiency virus (HIV) antigens. 2. The transfer of cell-mediated immunity to HIV antigens was accomplished by injecting iRNA into a Cebus monkey, as evaluated in vitro by leukocyte migration inhibition. The in vitro treatment of normal human leukocytes with iRNA also promoted the inhibition of leukocyte migration in the presence of HIV antigens. 3. These findings have important theoretical and potential practical applications in the field of Acquired Immunodeficiency Syndrome (AIDS).

Coal energy vs nuclear energy: a comparison of the radiological risks.

We examined past and current work comparing radiological risks from coal-fired and nuclear plants. We found some errors and under- and over-evaluations. They appear to be generally in the direction of maximizing coal risks and minimizing nuclear risks. Our analysis removes these apparent inconsistencies and takes full account of the Suess effect and shows that the radiological risks from coal-fired plants are fully counterbalanced by this effect and are, in any case, small in comparison with those from nuclear plants.

Quantitation of the soluble E-receptor of human T lymphocytes by rocket electrophoresis in the serum of patients with lepromatous and tuberculoid leprosy.

Human T lymphocytes carry a membrane receptor for sheep erythrocytes (E) which is responsible for the well-known phenomenon of E-rosette formation. This receptor has been related to CD2 molecules; it is present in a soluble form (Rs) in normal serum and may play an immunoregulatory role. In this study we quantitated soluble E-receptor in serum samples of 43 normal controls, 32 patients with tuberculoid leprosy and 53 with lepromatous leprosy, using rocket electrophoresis and an anti E receptor serum (anti-Rs) obtained from an adult sheep immunized with autologous E treated with Rs. In the 3 groups studied, the rocket means were respectively 5.0, 7.5 and 10.9 mm (p less than 0.001). We found abnormally high levels of Rs in the serum of various diseases associated with a depression of cell-mediated immunity. The increase of Rs levels in the serum may be one of the mechanisms responsible for the depression of cellular immunity in leprosy.