North Atlantic climate far more predictable than models imply.

Quantifying signals and uncertainties in climate models is essential for the detection, attribution, prediction and projection of climate change1-3. Although inter-model agreement is high for large-scale temperature signals, dynamical changes in atmospheric circulation are very uncertain4. This leads to low confidence in regional projections, especially for precipitation, over the coming decades5,6. The chaotic nature of the climate system7-9 may also mean that signal uncertainties are largely irreducible. However, climate projections are difficult to verify until further observations become available. Here we assess retrospective climate model predictions of the past six decades and show that decadal variations in North Atlantic winter climate are highly predictable, despite a lack of agreement between individual model simulations and the poor predictive ability of raw model outputs. Crucially, current models underestimate the predictable signal (the predictable fraction of the total variability) of the North Atlantic Oscillation (the leading mode of variability in North Atlantic atmospheric circulation) by an order of magnitude. Consequently, compared to perfect models, 100 times as many ensemble members are needed in current models to extract this signal, and its effects on the climate are underestimated relative to other factors. To address these limitations, we implement a two-stage post-processing technique. We first adjust the variance of the ensemble-mean North Atlantic Oscillation forecast to match the observed variance of the predictable signal. We then select and use only the ensemble members with a North Atlantic Oscillation sufficiently close to the variance-adjusted ensemble-mean forecast North Atlantic Oscillation. This approach greatly improves decadal predictions of winter climate for Europe and eastern North America. Predictions of Atlantic multidecadal variability are also improved, suggesting that the North Atlantic Oscillation is not driven solely by Atlantic multidecadal variability. Our results highlight the need to understand why the signal-to-noise ratio is too small in current climate models10, and the extent to which correcting this model error would reduce uncertainties in regional climate change projections on timescales beyond a decade.

Posterolateral transpedicular approach for ventrally seated cervicothoracic spinal cord lesions: how I do it.

BACKGROUND: Surgical exposure of lower cervical and upper thoracic intradural extramedullary lesions located along the ventral medulla are among the most complexes to address in spinal surgery, and their surgical removal carries a high risk. METHODS: We describe the surgical steps of a posterolateral transpedicular approach for resection of an intradural extramedullary lesion located anterolaterally at C7-T1 level. CONCLUSIONS: A posterolateral transpedicular approach is a safe and efficient surgical corridor to explore the ventral spinal cord and to have a direct access to lower cervical-upper thoracic lesions without the extensive manipulation of the spinal cord and the spine instability.

A novel BRAF mutation in association with primary amelanotic melanoma with oral metastases.

BACKGROUND: In the context of amelanotic melanoma, little is known on the genetic or molecular background that determines the onset of this peculiar phenotype of melanoma and its sites of metastatic spread. However, it appears that amelanotic melanomas frequently lack BRAF mutations. OBJECTIVE: To report the genetical analysis of one case amelanotic melanoma developing oral metastasis. METHODS: The BRAF mutational status of the primary lesion was assessed by both Sanger sequencing and pyrosequencing. RESULTS: Both methodologies showed changes in three nucleotides: C1796T; G1798A and T1799A. These mutations should result in a rare double aminoacid substitution in codons 599 and 600 of the BRAF protein (BRAF T599I/V600K). CONCLUSION: This unusual mutation was associated with an uncommon clinical phenotype of the primary tumour and with an unusual site of metastatic spread. In the lack of comparable data, a potential association between the unusual mutation and clinical findings remains a matter of further studies.

Exploring Synthetic Dihydrobenzofuran and Benzofuran Neolignans as Antiprotozoal Agents against Trypanosoma cruzi.

Chagas disease is a neglected tropical disease that affects more than 8 million people. Although there are therapies against this disease, the search for new drugs is important because the current treatments show limited effectiveness and high toxicity. In this work, eighteen dihydrobenzofuran-type neolignans (DBNs) and two benzofuran-type neolignans (BNs) were synthesized and evaluated against amastigote forms of two Trypanosoma cruzi strains. The in vitro cytotoxicity and hemolytic activity of the most active compounds were also evaluated and their relationships with T. cruzi tubulin DBNs were investigated by an in silico approach. Four DBNs demonstrated activity against the T. cruzi Tulahuen lac-Z strain (IC50 from 7.96 to 21.12 µM), and DBN 1 exhibited the highest activity against the amastigote forms of the T. cruzi Y strain (IC50 3.26 µM). Compounds 1-4 showed CC50 values higher than antitrypanosomal activities, except for DBN 3. All DBNs with antitrypanosomal activity demonstrated CH50 higher than 100 µM. The in silico results indicated that DBNs 1, 2, and 4 are capable of destabilizing the dynamics of the tubulin-microtubule from the vinca site. These compounds displayed promising in vitro activity against T. cruzi, especially compound 1, and can be considered molecular prototypes for the development of new antiparasitic drugs.

Activating c-KIT mutations in a subset of thymic carcinoma and response to different c-KIT inhibitors.

BACKGROUND: To analyze a multi-institutional series of type C thymic carcinomas (TCs) (including neuroendocrine tumors), focusing on the expression and mutations of c-KIT. MATERIALS AND METHODS: Immunohistochemical expression of c-KIT/CD117, p63, CD5 and neuroendocrine markers, as well as mutational analysis of c-KIT exons 9, 11, 13, 14, 17 by direct sequencing of 48 cases of TCs. Immunohistochemical and molecular data were statistically crossed with clinicopathological features. RESULTS: Overall, 29 tumors (60%) expressed CD117, 69% were positive for CD5 and 85% (41 cases) for p63. Neuroendocrine markers stained all six atypical carcinoids and five poorly-differentiated thymic squamous cell carcinomas. Overall, six CD117-positive cases (12.5%) showed c-KIT mutation. No mutation was detected in CD117-negative tumors and carcinoids. All the mutations were found in poorly-differentiated thymic squamous cell carcinomas expressing CD117, CD5, p63 and lacking neuroendocrine markers (6 of 12 cases with these features). Mutations involved exon 11 (four cases: V559A, L576P, Y553N, W557R), exon 9 (E490K) and exon 17 (D820E). CONCLUSIONS: All TCs need an immunohistochemical screening with CD117, while c-KIT mutation analysis is mandatory only in CD117-positive cases, particularly when coexpressing CD5 and p63, lacking neuroendocrine differentiation. The finding of c-KIT mutation can predict efficacy with different c-KIT inhibitors.

Analysis of MGMT promoter methylation status on intraoperative fresh tissue section from frameless neuronavigation needle biopsy of 25 patients with brain tumor.

Formalin fixation under conditions that adversely affected the quality of the DNA, or indeterminant assay, or extensive tumor necrosis can compromise the genetic analysis of a brain bioptic sample. The success of DNA extraction and Methyl Guanine Methyl Transferase (MGMT) promoter methylation testing could be improved by freezing of fresh tumor tissue at the moment of biopsy. To ensure an increased concentration of the DNA samples the withdrawal should be performed in an area with high probability of neoplastic cells. From May 2007 to January 2011 fifty-two frameless neuronavigation brain needle biopsy were performed at the Neurosurgery Unit of the "Arcispedale Santa Maria Nuova" City Hospital of Reggio Emilia. The "image-guided" neuronavigated protocol sampling provided withdrawal specimens highly correlated with neuroimaging characteristics of the lesions. In this study the Authors report the genetic analysis on 24 cases of freezing fresh tissue from brain needle bioptic sample starting from July 2008. The molecular determination of MGMT promoter was assessed with the Nested-Methylation Specific-Polymerase Chain Reaction on fresh or cryopreserved needle bioptic tissue. The genetic characterization was feasible in all the bioptic samples. The MGMT promoter was methylated in eleven patients, including a brain infection. The diagnostic yield of brain biopsy could be increased by the neuronavigated trajectories and the intraoperative frozen sections. In the future the availability of the molecular-genetic characterization of a brain tumor before open surgery will provide important information for the optimal treatment. The MGMT promoter status analysis on needle bioptic fresh tissue could be available also for that patient not eligible for surgical remotion of the tumor.

Detection of IDH1 mutations and the status of MGMT promoter on intraoperative fresh tissue section from frameless neuronavigation needle biopsy. Analysis on 17 patients with brain glial tumor ineligible for craniotomy and tumor resection.

It is well known that primary and secondary glioblastomas are histologically largely indistinguishable. Therefore, the detection of IDH1 mutations or the status of the MGMT promoter on a simple bioptic sample could be one of major diagnostic and prognostic importance for glial patients that complements clinical criteria for distinguishing secondary from primary glioblastomas and to predict a more favourable prognosis. Currently, biopsy is the method of choice to obtain tissue from intracranial lesions with uncertain neurodiagnostic findings or in deep locations, with a minimal invasive approach. The needle biopsy with frameless neuronavigation could provide a sampling with elevated diagnostic yield and high concentration of DNA, due to the "image-guided" computer assisted technique of needle insertion through the most neurodiagnostic representative tumor area. The freezing of fresh tumor tissue at biopsy could greatly improve the success of DNA extraction. The concentration of the DNA samples can also improved from a withdrawal in an area with high probability of neoplastic cells. The present study reports the results of 17 patients who had undergone frameless image-guided intracranial needle biopsy from April 2008 until July 2010 at Neurosurgery Unit of the "Arcispedale Santa Maria Nuova" of Reggio Emilia. For these patients the molecular determination of MGMT promoter was assessed with the Nested-Methylation Specific-Polymerase Chain Reaction and the screening of mutations in IDH1 e IDH2 genes was performer by polymerase chain reaction (PCR) and direct sequencing on fresh or cryopreserved needle bioptic tissue.

Homogeneous fluorescent immunoassay.

A fluorescent immunoassay based on the correlation of fluctuations in particle number measures the amount of tagged species bound to micrometer-sized beads and is insensitive to background fluorescence. Without separation steps, a competitive assay can resolve I nanogram of gentamicin per milliliter from a total sample volume of only 10 microliters.

Protein Z G79A and A-13G gene polymorphisms in Italian patients with Behçet's disease.

OBJECTIVE: To investigate potential associations between A-13G and G79A polymorphisms of the protein Z gene and venous thrombosis and other clinical manifestations in Italian patients with Behçet's disease (BD). METHODS: 176 Italian patients who satisfied the International Study Group criteria for BD and 134 healthy age- and sex- matched blood donors were genotyped for A-13G and G79A polymorphisms of the protein Z gene by molecular methods. 113 and 112 of the 176 BD patients were also genotyped for factor V Leiden and prothrombin gene G20210A polymorphisms. Serological HLA class B51 typing was performed by a standard microlymphocytotoxicity technique. The patients were subgrouped according to the presence or absence of clinical manifestations. RESULTS: The distribution of allele and genotype frequencies of A-13G and G79A polymorphisms did not differ significantly between BD patients and healthy controls.The frequencies of carriage rates of protein Z G79A and A-13G polymorphisms in BD patients with and without DVT were similar. Similarly, no associations between thrombotic events and the protein Z gene polymorphisms studied were observed in BD patients carrying factor V Leiden or prothrombin gene G20210A mutations. No significant associations were observed between protein Z polymorphisms and the occurrence of specific clinical findings. CONCLUSION: No association between DVT and A-13G or G79A polymorphisms of the protein Z gene was found in Italian BD patients. Furthermore, these protein Z polymorphisms in BD do not seem to increase the risk of DVT due to factor V Leiden or prothrombin gene G20210A mutations.

Toll-like receptor 4 (TLR4) gene polymorphisms in giant cell arteritis.

OBJECTIVE: To investigate potential associations between toll-like receptor 4 (TLR4) gene polymorphisms and susceptibility to, and clinical features of giant cell arteritis (GCA). METHODS: A total of 155 patients with biopsy-proven GCA who were residents of Reggio Emilia, Italy, and 210 population-based controls from the same geographical area were genotyped for two coding single nucleotide polymorphisms of TLR4 (Asp299Gly and Thr399Ile) by molecular methods. The patients were subgrouped according to the presence or absence of polymyalgia rheumatica and severe ischemic complications (visual loss and/or cerebrovascular accidents). RESULTS: The distribution of allele and genotype frequencies did not differ significantly between GCA patients and healthy controls. Carriers of the -299 G allele (G/A+ G/G) [odds ratio (OR) 1.78, 95% confidence intervals (CI) 0.90-3.50)] were more frequent among GCA patients than among the controls, but the difference was not statistically significant. No significant associations were found when GCA patients with and without PMR or with and without severe ischemic complications were compared. CONCLUSION: Our data suggest that the TLR4 gene polymorphisms are not associated with susceptibility to, and clinical expression of, GCA in Italian patients.

Toll-like receptor 4 (TLR4) gene polymorphisms in Italian patients with Behçet's disease.

OBJECTIVE: To investigate potential associations between toll-like receptor 4 (TLR4) gene polymorphisms and susceptibility to, clinical features, and severity of Behçet's disease (BD). METHODS: A total of 189 Italian patients who satisfied the International Study Group criteria for BD and 210 healthy age- and sex-matched blood donors were genotyped for two coding single nucleotide polymorphisms of TLR4 (Asp299Gly and Thr399Ile) by molecular methods. The patients were subgrouped according to the presence or absence of clinical manifestations. Severity score was calculated. RESULTS: The distribution of allele and genotype frequencies did not differ significantly between the BD patients and the healthy controls. No significant associations were found when BD patients with and those without clinical manifestations were compared. No association between TLR4 polymorphisms and severity score was observed. CONCLUSION: Our data suggest that the TLR4 gene polymorphisms are not associated with susceptibility to, clinical expression of, and severity of BD in Italian patients.

-463 G/A myeloperoxidase promoter polymorphism in giant cell arteritis.

OBJECTIVE: To investigate potential associations between-463 G/A myeloperoxidase (MPO) promoter polymorphism and susceptibility to, and clinical features of giant cell arteritis (GCA). METHODS: A total of 156 patients with biopsy-proven GCA who were residents of Reggio Emilia, Italy, and 235 population-based controls from the same geographic area were genotyped for-463 G/A promoter polymorphism of the MPO gene by molecular methods. The patients were subgrouped according to the presence or absence of polymyalgia rheumatica and severe ischaemic complications (visual loss and/or cerebrovascular accidents). RESULTS: The distribution of the MPO-G/A genotype differed significantly between patients with GCA and the controls (p(corr) = 0.003). Allele G was significantly more frequent in patients with GCA than in the controls (p(corr) = 0.0002, OR 2.0, 95% CI 1.4 to 2.9). Homozygosity for the G allele was significantly more frequent in patients with GCA than in controls (p(corr) = 0.0002, OR 2.2, 95% CI 1.4 to 3.4). No significant associations were found when patients with GCA with and without polymyalgia rheumatica or with and without severe ischaemic complications were compared. CONCLUSIONS: Our findings show that the-463 G/A promoter polymorphism of the MPO gene is associated with GCA susceptibility and support a role for MPO in the pathophysiology of GCA.

The codon 72 polymorphic variants of p53 in Italian rheumatoid arthritis patients.

OBJECTIVE: The p53 tumor suppressor protein plays an important role in cell apoptosis. The wild type p53 protein presents a common polymorphism at position 72 resulting in either a proline or an arginine residue at this position, leading to differences between the two variants in the induction of apoptosis. We examined the possible associations of this polymorphism with the occurrence of rheumatoid arthritis (RA) and its severity in a series of RA patients of Italian origin. METHODS: 170 consecutive RA patients fulfilling the 1997 ACR criteria and seen over a 4-month period in our rheumatology centre were studied. The medical records of the patients were reviewed for demographic and clinical parameters. Radiographs of the hands and feet taken at disease onset and after 5 years were available for 122 of the patients and were used to determine the presence and number of erosions, which were scored according to the modified Sharp/van der Heijde method (S/vdH). All of the RA patients and controls were genotyped by the polymerase chain reaction and allele-specific oligonucleotide techniques for p53 gene polymorphism Arg/Pro at codon 72. RESULTS: The distribution of the polymorphism of Arg/Pro 72 did not differ significantly between patients and healthy controls (Arg/Arg 47.1 vs 48.5%, Arg/Pro 43.5% vs 42%, Pro/Pro 9.8 vs 9.5% respectively, p=ns). Patients carrying the Pro/Pro genotype had a significantly higher percentage of erosive disease at year 5 compared with patients carrying the Arg/Arg genotype (Pro/Pro 93%, Arg/Arg 52%, p=0.0001). The mean number of eroded joints per patient at 5 years was higher in the Pro/Pro subgroup and significantly lower in the Arg/Arg subgroup (Pro/Pro 13.2, Arg/Arg 3.6, p=0.0001). The mean S/vdH erosive score, joint space narrowing score and total damage score were significantly higher in the Pro/Pro subgroup compared with the Arg/Arg and Arg/Pro subgroups. CONCLUSION: In the Italian population there is no association between codon 72-p53 gene polymorphism and the occurrence of RA. However, this polymorphism is associated with the structural damage of the disease.

Fluorescence fluctuation immunoassay.

The homogeneous fluorescent immunoassay described above allows one to measure the brightness of fluorescently tagged carrier particles that are suspended in a background of free, unbound fluorescent sources. We have demonstrated the feasibility of our technique using a gentamicin competitive assay as well as idealized model systems. We have seen that the fluctuation-correlation method is able to discriminate against free background sources because each fluorescing particle in solution contributes to the correlation peak [Eq. (4)] with a weighting equal to the square of its respective intensity. Hence, a few very bright sources contribute disproportionately to the "signal" relative to many weak ones. To take advantage of this property, one would therefore design an assay that uses relatively larger carrier particles, each of which is capable of binding on the order of 10(3) to 10(4) tagged antibodies or antigens. Unfortunately, the nonlinear dependence of the correlation peak on the brightness of the fluorescing species causes the technique to be perturbed by carrier particle aggregation; the apparent bound fluorescence intensity increases with the extent of aggregation. The latter may be an unavoidable consequence of performing assays using raw blood serum, for example. The ultimate usefulness of this method will depend on its sensitivity and speed when applied to "real" assays of clinical significance. These characteristics will be influenced by a number of technical details. Given our limited experience with the method thus far, it would appear that its principal drawback is its relatively slow speed. In order to decrease the time needed for a reliable measurement, one must average the random fluctuations in the fluorescent intensity to zero more quickly. In principle, this can be accomplished by decreasing the shot noise by collecting a larger fraction of the fluorescent light, and increasing the sampling rate. The method requires rather complicated instrumentation; it is by no means clear that this level of complexity is justified given the realistic level of sensitivity that will be obtained by this technique.

Quantitative verification of the existence of high molecular weight protein aggregates in the intact normal human lens by light-scattering spectroscopy.

The method of quasi-elastic light-scattering spectroscopy was used to establish quantitatively the concentration of high mmolecular weight (HMW) aggregates present in the normal human intact lens as a function of age. The concentration of HMW proteins increases monotonically with age. HMW proteins are absent in the infant lens, but represent 3% of the total soluble lens protein at age 60 years. The percent concentration of HMW proteins measured in intact lenses of various ages by quasi-elastic light scattering is in striking agreement with values determined biochemically.

-344C/T polymorphism of CYP11B2 gene in Italian patients with idiopathic low renin hypertension.

Most patients with low renin essential hypertension are not qualitatively different from patients with idiopathic hyperaldosteronism, as in both conditions aldosterone secretion is not appropriately reduced. The aim of the study was to investigate allele and genotype frequencies of the -344C/T polymorphism, located in the promoter region of the aldosterone synthase gene, in 83 patients with idiopathic low renin hypertension characterized by an increased aldosterone to renin ratio, including both patients with low renin essential hypertension (n=53) and subjects with idiopathic hyperaldosteronism (n=30), compared with 78 patients with normal to high renin essential hypertension and 126 normotensive control subjects. The relationship of -344C/T genotypes to basal and postcaptopril plasma aldosterone/plasma renin activity ratio was also examined in the entire hypertensive population. An increased frequency of the T allele and a relative excess of TT homozygosity over CC homozygosity were found in patients with idiopathic low renin hypertension in comparison with both normal to high renin hypertensives and normotensive controls. A higher post-captopril aldosterone to renin ratio was found in the hypertensives with TT genotype than in those with CC genotype, and TT+TC genotypes were associated with a smaller decrease in the aldosterone-to-renin ratio elicited by captopril administration. The present study suggests that the -344C/T polymorphism, or a functional variant in linkage disequilibrium with it, may play a role in the abnormal regulation of aldosterone secretion in idiopathic low renin hypertension.

Increased plasma levels of platelet-derived growth factor (PDGF-BB + PDGF-AB) in patients with never-treated mild essential hypertension.

Platelet-derived growth factor (PDGF) could play a role in both vascular hypertrophy and atherosclerotic disease associated with hypertension. To assess whether plasma PDGF level is increased in mild essential hypertension, we measured plasma PDGF concentration in 25 never-treated patients with uncomplicated mild essential hypertension and in 22 normotensive healthy subjects. To evaluate the contribution of platelets to plasma PDGF in the two groups, we also measured plasma beta-thromboglobulin (BTG). Measurement of PDGF was carried out through an enzyme-linked immunoadsorbent assay, which detects two PDGF dimers, namely PDGF-BB and PDGF-AB. Both plasma PDGF and BTG were higher in the hypertensive than in the normotensive subjects. The ratio of PDGF to BTG was similar in the two groups. Plasma PDGF was weakly correlated with plasma BTG in the normotensive subjects, whereas this relationship was lost in the hypertensive patients. Our results suggest that the increase in plasma PDGF (PDGF-AB + PDGF-BB) in never-treated essential hypertension is mainly due to platelet activation. The increased circulating level of PDGF could play a role in the vascular structural changes associated with hypertension.

Intercellular adhesion molecule 1 (ICAM-1) gene polymorphisms in Italian patients with rheumatoid arthritis.

AIMS: Rheumatoid arthritis (RA) has a wide range of clinical expressions which probably reflects different genetic backgrounds. Intercellular adhesion molecule-1 (ICAM-1) plays an important role in the inflammatory synovial activity in RA. The aim of this study was to examine the potential associations of ICAM-1 gene polymorphisms with RA and its severity. METHODS: Seventy-eight seropositive Italian RA patients with erosive disease entered the study. Radiographs of hands and feet 5 years after the diagnosis were available for 68 patients and were evaluated for the number of eroded joints. We obtained an erosive score for each patient by counting the number of joints with at least one erosion. Patients in the upper part of the distribution over the median were considered as fast eroders (FE) and the others as slow eroders (SE). Patients' records were also evaluated for the presence of extra-articular features. 228 healthy subjects of the same ethnic origin were selected as a control group. All of the RA patients and controls were genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for ICAM-1 polymorphisms G/R at codon 241 (exon 4) and E/K at codon 469 (exon 6). RESULTS: The carriage rate of allele R241 was significantly higher in RA patients than in healthy controls (12.8% versus 5.7%, p = 0.039; odds ratio: 2.4 [95% CI 1.02 to 5.79]). The allele frequencies and carriage rate of the E 469 gene did not differ significantly between RA patients and the control group. When we compared the control group with the patients with more or less severe disease (presence or absence of extra-articular features, SE and FE) we found that only the group of patients with the more favourable course maintained a significant difference in the carriage rate of R241 (16.7 vs 5.7%, p = 0.009 for patients without extra-articular features and 18.9 vs 5.7%, p = 0.004 for SE patients). CONCLUSION: Our preliminary findings show that G/R 241 polymorphism of ICAM-1 is associated with RA, and that this confers a reduced risk of extra-articular manifestations and is associated with a slow rate of joint destruction.

Modifications in the psychological and behavioural structure of women after mastectomy.

The authors report a psychological equiry carried out by interviews and tests on mastectomised patients to find out the psycho-effective and behavioural implications related to this type of mutilation, to the type of preoperative information and to the relation with the doctor in charge, also to an eventual morphological reconstruction of the breast. They also analyse the relation between the objective result evaluated by the surgeon and the subjective evaluation of the patient. Some results of breast reconstruction are presented.

Study of lung reactions in six asymptomatic workers occupationally exposed to hard metal dusts.

The description of one case of pulmonary fibrosis in a group of workers occupationally exposed to hard metal dusts with high concentrations of cobalt (50-90%), followed for five years, prompted us to perform a cytological examination on the bronchoalveolar lavage fluid plus determination of the lymphocytic subpopulations in six asymptomatic workers with the longest exposure. Bronchoalveolar lavage performed 16 hours (3 cases) or 48 hours (3 cases) after the end of the workshift showed a lymphocytosis with inversion of the helper/suppressor ratio in 3 cases. This demonstrates an immune response at deep lung level. No difference was observed between a subject with ascertained interstitial fibrosis and the other subjects. Furthermore, bronchoscopy revealed marked inflammatory reaction of the tracheobronchial mucosa.