Pediatric emergency care admissions for somatic symptom disorders during the COVID-19 pandemic

During the COVID-19 pandemic, children and adolescents with psychiatric disorders experienced an exacerbation of their symptoms with more access to the emergency department (ED). However, little is known about the experience of somatic symptom disorders (SSDs) during the COVID-19 pandemic in children. Therefore, we aimed to compare the rates of pediatric ED admissions for SSDs before and during the COVID-19 pandemic and to understand whether the relative risk of ED admissions for SSDs changed between the two periods. We retrospectively enrolled all children between 4 and 14 years admitted for SSDs in the pediatric ED of Santobono-Pausilipon Hospital, Naples, Italy, from March 11th, 2020, to March 11th, 2021 (pandemic period), and in the same time period of the previous year (pre-pandemic period). We identified 205/95,743 (0,21%) children with SSDs presenting in ED in the pre-pandemic year and 160/40,165 (0,39%) in the pandemic year (p < 0.05). Considering the accesses for age, we observed a relative decrease of the accesses for SSDs over 12 years old (IRR 0,59; CI 0,39-0,88), while we found no differences under 12 years old (IRR 0,87; CI 0,68-1,10).   Conclusion: In this study, we found that despite the massive decrease in pediatric admissions due to the COVID-19 pandemic, somatic symptom disorders' admissions to the pediatric ED increased, suggesting an impact of the pandemic also on pediatric psychiatric disorders. What is Known: • During the COVID -19 pandemic, children and adolescents with a psychiatric disorder experienced exacerbation of their symptoms with more accesses in Emergency Department. What is New: • We found that despite the massive decrease of the pediatric admissions due to the COVID-19 pandemic, somatic symptom disorders admissions in healthy children to the pediatric Emergency Department increased ,suggesting an impact of the pandemic also on the pediatric psychiatric disorders.

Middle-Level Features for the Explanation of Classification Systems by Sparse Dictionary Methods

Machine learning (ML) systems are affected by a pervasive lack of transparency. The eXplainable Artificial Intelligence (XAI) research area addresses this problem and the related issue of explaining the behavior of ML systems in terms that are understandable to human beings. In many explanation of XAI approaches, the output of ML systems are explained in terms of low-level features of their inputs. However, these approaches leave a substantive explanatory burden with human users, insofar as the latter are required to map low-level properties into more salient and readily understandable parts of the input. To alleviate this cognitive burden, an alternative model-agnostic framework is proposed here. This framework is instantiated to address explanation problems in the context of ML image classification systems, without relying on pixel relevance maps and other low-level features of the input. More specifically, one obtains sets of middle-level properties of classification inputs that are perceptually salient by applying sparse dictionary learning techniques. These middle-level properties are used as building blocks for explanations of image classifications. The achieved explanations are parsimonious, for their reliance on a limited set of middle-level image properties. And they can be contrastive, because the set of middle-level image properties can be used to explain why the system advanced the proposed classification over other antagonist classifications. In view of its model-agnostic character, the proposed framework is adaptable to a variety of other ML systems and explanation problems.

Behaviour of dental pulp stem cells on different types of innovative mesoporous and nanoporous silicon scaffolds with different functionalizations of the surfaces

Dental pulp stem cells (DPSCs) are stem cells found in the dental pulp. The ability of DPSCs to differentiate towards odontoblastic and osteoblastic phenotype was reported first in the literature, then in the following years, numerous studies on odontogenesis were carried out, starting from mesenchymal stem cells isolated from tissues of dental and oral origin. The aim of this research was to evaluate the behaviour of DPSCs grown on silicon nanoporous and mesoporous matrices and differentiated towards the osteogenic phenotype, but also to investigate the use of DPSCs in pilot studies focused on the biological compatibility of innovative dental biomaterials. Twenty-eight silicon samples were created with standardized procedures. These scaffolds were divided into samples made of silicon bulk, nanoporous silicon, mesoporous silicon, nanoporous silicon functionalized with (3-Aminopropyl) Trimethoxysilane (APTMS) and methanol (MeOH), nanoporous silicon functionalized with (3-Aminopropyl) Trimethoxysilane (APTMS)/toluene, mesoporous silicon functionalized with (3-Aminopropyl) Trimethoxysilane (APTMS) and methanol (MeOH) andmesoporous silicon functionalized with (3-Aminopropyl) Trimethoxysilane (APTMS)/toluene. DPSC proliferation on the tested silicon scaffolds was analyzed at 3 and 5 days. The assay showed that DPSCs proliferated better on mesoporous scaffolds functionalized with APTMS/toluene compared to a silicon one. These results show that the functionalization of silicon scaffold with APTMS/toluene supports the growth of DPSCs and could be used for future applications in tissue engineering.

[The results of the experimental prospective study on the effectiveness and efficiency of the implementation of clinical pathways]

Our study was undertaken to determine how the use of care pathways in hospital affected the quality of the care of the patients. We performed a cluster-randomized trial. The use of diagnostic procedures and of medical treatments was more appropriate in the care pathways group, as well as the discharge process. As a consequence the outcomes indicators adopted in our study showed better performances in the care pathways group when compared to the usual care group. Our study added evidences on the value of clinical pathways that can be effectively used to improve the quality of hospital care. The use of CP helped to create a constant dialogue within the clinicians, ensured that important areas of treatment were not overlooked and unnecessary delays were prevented by timely interventions. We think that our results are reliable because we adopted a cluster-randomized controlled trial design that is widely accepted as the most reliable method of determining effectiveness of complex interventions in healthcare.

Surgical treatment with Ligasure Precise of schwannoma of brachial plexus: case report

English version We present a case of bulky schwannoma arising from the brachial plexus treated by a new surgical device. A 38-year-old man presented with a slow-growing left-sided supraclavicular mass and complained paresthesia of the third and forth fingers of the hand and forearm weakness. Physical examination revealed Tinel's sign. A CT-scan revealed a solid mass situated in the left profound supraclavicular fossa. The tumour was resected with the utilization of bipolar vessel sealing system (Ligasure Precise). This device is very useful in sutureless removal of masses localized in deep supraclavicular fossa. During the operation, care was taken to preserve the nerve function.

Evaluation of the biomechanical behavior of maxillary central incisors restored by means of endocrowns compared to a natural tooth: A 3D static linear finite elements analysis

OBJECTIVE

The present study aimed at evaluating different restoring configurations of a crownless maxillary central incisor, in order to compare the biomechanical behavior of the restored tooth with that of a sound tooth.

MATERIALS AND METHODS

A 3D FE model of a maxillary central incisor is presented. An arbitrary static force of 10 N was applied with an angulation of 125 degrees to the tooth longitudinal axis at level of the palatal surface of the crown. Different material configurations were tested: composite, syntered alumina, feldspathic ceramic endocrowns and glass post resorations with syntered alumina and feldspathic ceramic crown.

RESULTS

High modulus materials used for the restoration strongly alter the natural biomechanical behavior of the tooth. Critical areas of high stress concentration are the restoration-cement-dentin interface both in the root canal and on the buccal and lingual aspects of the tooth-restoration interface. Materials with mechanical properties underposable to that of dentin or enamel improve the biomechanical behavior of the restored tooth reducing the areas of high stress concentration.

SIGNIFICANCE

The use of endocrown restorations present the advantage of reducing the interfaces of the restorative system. The choice of the restorative materials should be carefully evaluated. Materials with mechanical properties similar to those of sound teeth improve the reliability of the restoartive system.

Canalicular adenoma of the parotid gland: a case report

Canalicular adenoma is an uncommon benign neoplasm that occurs almost exclusively in the upper lip and, very rarely, in other sites. We describe a case arising in the left parotid gland as a firm, painful mass, in order to underline morphological and immunohistochemical findings, particularly in relation to differential diagnosis with low-grade carcinomas of the salivary glands.

Effect of non-steroidal anti-inflammatory drugs on colon carcinoma Caco-2 cell responsiveness to topoisomerase inhibitor drugs

Numerous studies demonstrate that the chemopreventive effect of non-steroidal anti-inflammatory drugs on colon cancer is mediated through inhibition of cell growth and induction of apoptosis. For these effects non-steroidal anti-inflammatory drugs have been recently employed as sensitising agents in chemotherapy. We have shown previously that treatments with aspirin and NS-398, a cyclo-oxygenase-2 selective inhibitor, affect proliferation, differentiation and apoptosis of the human colon adenocarcinoma Caco-2 cells. In the present study, we have evaluated the effects of aspirin and NS-398 non-steroidal anti-inflammatory drugs on sensitivity of Caco-2 cells to irinotecan (CPT 11) and etoposide (Vp-16) topoisomerase poisons. We find that aspirin co-treatment is able to prevent anticancer drug-induced toxicity, whereas NS-398 co-treatment poorly affects anticancer drug-induced apoptosis. These effects correlate with the different ability of aspirin and NS-398 to interfere with cell cycle during anticancer drug co-treatment. Furthermore, aspirin treatment is associated with an increase in bcl-2 expression, which persists in the presence of the anticancer drugs. Our data indicate that aspirin, but not NS-398, determines a cell cycle arrest associated with death suppression. This provides a plausible mechanism for the inhibition of apoptosis and increase in survival observed in anticancer drug and aspirin co-treatment.

3D-finite element analyses of cusp movements in a human upper premolar, restored with adhesive resin-based composites

The combination of diverse materials and complex geometry makes stress distribution analysis in teeth very complicated. Simulation in a computerized model might enable a study of the simultaneous interaction of the many variables. A 3D solid model of a human maxillary premolar was prepared and exported into a 3D-finite element model (FEM). Additionally, a generic class II MOD cavity preparation and restoration was simulated in the FEM model by a proper choice of the mesh volumes. A validation procedure of the FEM model was executed based on a comparison of theoretical calculations and experimental data. Different rigidities were assigned to the adhesive system and restorative materials. Two different stress conditions were simulated: (a) stresses arising from the polymerization shrinkage and (b) stresses resulting from shrinkage stress in combination with vertical occlusal loading. Three different cases were analyzed: a sound tooth, a tooth with a class II MOD cavity, adhesively restored with a high (25 GPa) and one with a low (12.5GPa) elastic modulus composite. The cusp movements induced by polymerization stress and (over)-functional occlusal loading were evaluated. While cusp displacement was higher for the more rigid composites due to the pre-stressing from polymerization shrinkage, cusp movements turned out to be lower for the more flexible composites in case the restored tooth which was stressed by the occlusal loading. This preliminary study by 3D FEA on adhesively restored teeth with a class II MOD cavity indicated that Young's modulus values of the restorative materials play an essential role in the success of the restoration. Premature failure due to stresses arising from polymerization shrinkage and occlusal loading can be prevented by proper selection and combination of materials.

Factors associated with noncompliance with psychiatric outpatient visits

Adherence to recommended services is essential for long-term effectiveness of ambulatory treatment programs, but factors associated with such adherence are not securely established. We evaluated attendance at 896 scheduled psychiatric clinic visits for 62 patients at a major psychiatric teaching hospital. Visit adherence was found to be significantly higher among patients in an acute stage of illness, those with a personality disorder, those with a post-high-school education, and those living alone. Adherence was also higher when visits were routinely scheduled, when the intervisit interval was shorter, and when the visit entailed psychotherapy rather than pharmacotherapy.

IGF-II/IGF-I receptor pathway up-regulates COX-2 mRNA expression and PGE2 synthesis in Caco-2 human colon carcinoma cells

Nonsteroidal anti-inflammatory drugs reduce the risk of colon cancer and this effect is mediated in part through inhibition of type 2 prostaglandin endoperoxide synthase/ cyclo-oxygenase (COX-2). In the present study, we demonstrate that COX-2 expression and PGE2 synthesis are up-regulated by an IGF-II/IGF-I receptor autocrine pathway in Caco-2 colon carcinoma cells. COX-2 mRNA and PGE2 levels are higher in proliferating cells compared with post-confluent differentiated cells and in cells that constitutively overexpress IGF-II. Up-regulation of COX-2 expression by IGF-II is mediated through activation of IGF-I receptor because: (i) treatment of Caco-2 cells with a blocking antibody to the IGF-I receptor inhibits COX-2 mRNA expression; (ii) transfection of Caco-2 cells with a dominant negative IGF-I receptor reduces COX-2 expression and activity. Also, the blockade of the PI3-kinase, that mediates the proliferative effect of IGF-I receptor in Caco-2 cells, inhibits IGF-II-dependent COX-2 up-regulation and PGE2 synthesis. Moreover, COX-2 expression and activity inversely correlate with the increase of apoptosis in parental, IGF-II and dominant-negative IGF-I receptor transfected cells. This study suggests that induction of proliferation and tumor progression of colon cancer cells by the IGF-II/IGF-I receptor pathway may depend on the activation of COX-2-related events.

[Palatal angioleiomyoma. A clinical case]

A case of angioleiomyoma localized at the level of the soft palate is reported. The 31-year-old patient presented a non-pathognomonic clinical picture and the anamnestic finding of the relatively slow growth of the neoformation raised problems of differential diagnosis in relation to benign growth and lesion of a non-neoplastic nature. The differential diagnosis was only obtained with histological examination of biopsy material.

Carbon fiber post adhesion to resin luting cement in the restoration of endodontically treated teeth

Carbon fiber posts (CFP) are widely used in the restoration of endodontically treated teeth to enhance the mechanical behavior in spite of metallic posts and to prevent vertical fractures of the tooth under chewing loads. The post is cemented inside the canal lumen using polymer resins with Young's modulus lower than dentine. In this conditions the stress concentration is located at the post-cement interface and in the cement bulk itself, preserving radicular dentine from dangerous stress accumulation. The mechanical resistance of CFP posts cemented in human dentine was evaluated by the means of mechanical pull-out tests assisted by the finite element analysis. The average bond strength and the critical stress values of the CHP-cement interface were 25 MPa and 50 MPa respectively.

Cisplatin-epirubicin-paclitaxel weekly administration in advanced breast cancer: a phase I study of the Southern Italy Cooperative Oncology Group

PURPOSE

Both cisplatin and epirubicin have been shown to enhance the antitumor activity of paclitaxel in vitro. Weekly administration could result in a substantial improvement in the therapeutic index of cisplatin and paclitaxel. This study was aimed at determining the MTDs of epirubicin and paclitaxel given weekly with a fixed dose of cisplatin.

PATIENTS AND METHODS

Sixty-three breast cancer patients with advanced disease (24 locally advanced and 39 metastatic), who had not received prior chemotherapy (except adjuvant), received weekly cisplatin (CDDP) doses of 30 mg/m2 together with escalating doses of paclitaxel (PTX) and epirubicin (EPI) for a minimum of six cycles. The dose escalation was stopped if DLT occurred during the first six treatment cycles in > 33% of patients of a given cohort.

RESULTS

Nine different dose levels were tested, for a total of 506 weekly cycles delivered. G-CSF support on days 3-5 of each week was also given in the last four cohorts (24 patients). An overall 11 patients showed DLT in the first six cycles. EPI and PTX doses up to 40 and 85 mg/m2/week, respectively, were safely delivered without G-CSF support. However, the actually delivered mean dose intensity was only 64% in this cohort. Therefore, the dose escalation continued with the addition of filgrastim from day 3 to day 5 each week. Doses of EPI and PTX up to 50 and 120 mg/m2/week were administered without observing DLT in the first six cycles in more than one third of the patients enrolled. No toxic deaths were observed. Only two patients had to be hospitalized because of sepsis. Grade 3-4 neutropenia, thrombocytopenia, and anemia occurred in 25, 9, and 16 patients, respectively. Alopecia was almost universal. Other nonhematologic toxicities were generally mild, being of grade 3-4 in only eight patients (fatigue and loss of appetite in two cases, diarrhoea in four cases, peripheral neuropathy and mucositis in one case). Fifteen complete and 37 partial responses have been registered for an 82% (95% CI = 71-91) overall clinical response rate (ORR). Eight complete and 14 partial responses occurred in the 24 patients with locally advanced disease, for a 92% (95% CI = 73-99) ORR, as compared to seven complete and 23 partial responses in the 39 women with metastatic disease, 77% (95% CI = 61-89). A clear dose-response relationship was not observed, since an overall response rate of at least 70% was achieved at all dose levels. However, the ORR increased to 92% in the last four cohorts which included patients who received higher doses of EPI and PTX with G-CSF support. All of the 24 patients with locally advanced disease underwent modified radical mastectomy with axillary dissection. Three of them showed no invasive cancer on pathologic examination, and in another five patients a tumor smaller than 1 cm was found in the surgical specimen of the breast. At a nine-month median follow-up (range 2-14), 11 patients have progressed and three have died. Twenty-three out of 24 patients who underwent surgery are still free from progression. The one-year projected progression-free survival is 77% for the whole population.

CONCLUSIONS

The CDDP/EPI/PTX weekly administration is a well tolerated and very effective approach in advanced breast cancer patients. Full doses of all the three drugs can be delivered even in absence of G-CSF support. A very impressive increment of the dose-intensity can be obtained, however, by adding filgrastim. A phase II study is under way to better define the therapeutic efficacy of this regimen in patients with advanced breast cancer.

Cell cycle block at G1-S or G2-M phase correlates with differentiation of Caco-2 cells: effect of constitutive insulin-like growth factor II expression

BACKGROUND & AIMS

We have previously shown that autocrine insulin-like growth factor (IGF)-II synthesis through IGF-I receptor stimulates proliferation and inhibits differentiation of Caco-2 cells. To demonstrate whether differentiation of Caco-2 cells is dependent on cell growth status, we analyzed the effect of cell cycle arrest on differentiation of wild-type and IGF-II-overexpressing cells.

METHODS

Cells were treated with drugs that inhibit the progression either to S phase (l-b-D-arabinofuranosylcytosine or M phase (nocodazole). Cell differentiation was analyzed by assessing apolipoprotein A-1 and sucrase-isomaltase expression. Cell proliferation and DNA content were assessed by thymidine incorporation and fluorescence-activated cell sorter analysis, respectively. Cell cycle regulatory molecules were analyzed by assessing p21 and retinoplasma protein (pRb) expression and pRb phosphorylation.

RESULTS

Cell cycle block at G1-S phase was associated with increased expression of differentiation markers in both parental and IGF-II-transfected cells. On the contrary, cell cycle arrest at G2-M phase correlated with the expression of differentiation markers in parental but not in IGF-II-transfected cells. Constitutive IGF-II-expressing cells actively incorporated thymidine and showed an increase in the proportion of cells with >4N DNA ploidy in the presence of nocodazole. Nocodazole treatment of constitutive IGF-II-expressing cells stimulated p21 expression in the presence of hyperphosphorylated pRb.

CONCLUSIONS

The data show that cell cycle arrest increases differentiation of Caco-2 cells. IGF-II-mediated proliferation may prevent cell differentiation through effects on control cell checkpoint proteins.

Cisplatin-topotecan-paclitaxel weekly administration with G-CSF support for ovarian and small-cell lung cancer patients: a dose-finding study

PURPOSE

Paclitaxel (PTX) and topotecan (TPT) have shown promising antitumor activity in both ovarian cancer (OC) and small-cell lung cancer (SCLC) patients. This phase I study was aimed at determining the maximum tolerable dose (MTD) of TPT given weekly over 30 min in combination with fixed doses of cisplatin (CDDP) and (PTX), and with G-CSF support.

PATIENTS AND METHODS

Forty-four patients with OC (19) or SCLC (25), either chemo-naïve (20) or pretreated (24) received CDDP 40 mg/m2, PTX 85 mg/m2 (one-hour infusion) and escalating TPT doses (starting from 0.75 mg/m2) in a 30-min infusion in weekly administration. Filgrastim 5 mg/kg was administered on days 3 to 5 of each week.

RESULTS

Eight different dose levels were tested for a total of 295 delivered cycles. The dose escalation was interrupted at the TPT dose of 2.50 mg/m2. No toxic deaths occurred in this study. Grade 3 to 4 neutropenia, thrombocytopenia, and anemia occurred in 15 patients (36 cycles), seven patients (15 cycles), and four patients (five cycles), respectively. Severe vomiting and diarrhoea occurred in seven and four patients. Peripheral neuropathy was recorded in 11 patients (42 cycles), but it was never severe. An overall 11 of 19 (58%) OC and 11 of 25 (44%) SCLC patients obtained objective responses. Eight patients showed complete responses (three OC and three SCLC). Among the 20 chemo-naïve patients, 9 of 11 (82%) OC and seven of nine (78%) SCLC responded.

CONCLUSIONS

The CDDP/TPT/PTX weekly administration with filgrastim support represents a well-tolerated and active therapeutic approach in both chemo-naïve and pretreated OC and SCLC patients. A weekly dose of TPT of 2.25 mg/m2 is recommended for the phase II study.

Scintimammography with 99mTc-MDP: experience of the National Cancer Institute of Naples

The role of scintimammography with 99mTc-MDP was investigated in patients with mammographic or clinical evidence of breast lesions, suspicious for malignancy, in our Department at the National Cancer Institute of Naples. The end-point of the study was to assess the uselfulness of this test in diagnosing or ruling out breast cancer in more than 2000 women. Scintimammography results were compared with those of mammography and ultrasound and categorized according to histological findings. Overall sensitivity was 92%, specificity was 90%, and accuracy 91%. Sensitivity was affected by the lesions exceeding 12 mm and specificity by sclerotic and/or hyaline or myxoid fibroadenomas, which may be positive. The major advantages of scintimammography appeared in the study of calcifications without a mass and of the indirect mammographic signs of breast cancer, such as distortion and asymmetry. Scintimammography with 99mTc-MDP is a reliable, safe and highly cost-effective procedure to diagnose or to rule out breast cancer, after mammography and ultrasound have yielded questionable results.

A finite-element model study of occlusal schemes in full-arch implant restoration

A three-dimensional finite-element model of a human mandible is presented, and the stresses and deformations computed for loading states induced by two different gnathologic reconstructions using six and four implants are discussed. Occlusal canine guidance and posterior and anterior group functions on cantilevered and distally supported prostheses have been simulated. The stress distributions generated by the different loading conditions on either the osseointegrated prosthesis or the bone tissue surrounding the implants are described. The analysis of the stress distribution on the working side reveals that the posterior group function undergoes a reduction in stress intensity on the cortical bone surrounding the implants (especially for the distal implant) compared with the anterior group function and canine guidance in both gnathologic reconstructions.

Effect of aspirin on cell proliferation and differentiation of colon adenocarcinoma Caco-2 cells

Several lines of evidence suggest that long-term treatment with non-steroidal anti-inflammatory drugs may reduce the risk of colon cancer and the size and number of colonic polyps in patients with familial adenomatous polyposis. Aspirin has also been shown to inhibit cell proliferation in human tumor cell lines and to induce apoptosis in colonic mucosa of familial polyposis patients. To elucidate the molecular mechanisms of the antiproliferative action of aspirin, we studied the effects of aspirin on cell growth and differentiation of the human colon carcinoma Caco-2 cell line. These cells represent a useful tool for studying the mechanisms involved in the regulation of cell growth and differentiation of intestinal epithelial cells since they spontaneously differentiate into polarized cells, expressing brush border enzymes. We show in this study that aspirin (0.1-10 mM) induces a profound inhibition of cell replication as assessed either by cell counts or thymidine incorporation. Moreover, aspirin concentrations of 5 and 10 mM induce apoptosis, whereas concentrations of 1 and 2 mM do not. The inhibition of growth is associated with a dose-dependent reduction in insulin-like growth factor II mRNA expression and with an increase in sucrase activity (a brush border enzyme) and apolipoprotein A-I mRNA expression, 2 specific markers of the differentiative status of this cell line. Our data thus show that aspirin-dependent inhibition of cell growth is associated with the enterocyte-like differentiation of Caco-2 cells.

Analysis of magnetization transfer effects on T1-weighted spin-echo scans using a simple tissue phantom simulating gadolinium-enhanced brain lesions

The purpose of this study was to analyze the effect of several magnetization transfer (MT) pulse and T1-weighted spin-echo (SE) sequence parameters on lesion-to-background contrast, using a simple tissue phantom emulating the T1 relaxation and MT properties of gadolinium-enhanced brain lesions. Eggbeaters (Nabisco Inc., East Hanover, NJ) liquid egg product was doped with gadolinium in six concentrations from .0 to 1.0 mmol and cooked. The gadolinium-doped egg phantom and normal volunteer brains were studied using an SE sequence with TE = 20 msec and high power, pulsed, off-resonance MT saturation. The effects of MT pulse frequency offset (1,000-6,000 Hz), sequence repetition time (TR = 500-1,000 msec, with MT power held constant), and slice-select flip angle (60-120 degrees) on the magnetization transfer ratio (MTR) and the simulated lesion-to-background contrast were determined at the different "intralesion" gadolinium concentrations. The MTR and lesion-to-background contrast of all materials were greatest at narrow MT pulse frequency offsets. There was in inverse relationship between gadolinium concentration and MTR and a positive correlation between the gadolinium concentration and lesion-to-background (L/B) contrast, a weak negative correlation between slice-select flip angle and L/B, and a negative correlation between TR and L/B. The relaxation properties and MT behavior of the egg phantom are close to that expected for enhancing brain lesions, allowing a rigorous analysis of several variables affecting lesion-to-background contrast for high MT power, T1-weighted SE sequences.

[Silibinin and acute poisoning with Amanita phalloides]

The aim of the present study was to show the therapeutic effect of silibinin dihemisuccinate in a case of intoxication by mushrooms of Amanita gender. We report a clinical case of a 4-person family intoxicated by ingestion of mushrooms Amanita phalloides and admitted to the center for poisoning treatment of the Hospital "A. Cardarelli" in Naples. Although all were treated with standard therapy, there was a worsening of the clinical picture till the third day, when it was decided to add silibinin dihemisuccinate by the intravenous route to the therapy. After the beginning of silibinin administration the patients showed a favourable course with a rapid resolution of the clinical picture, although the prognosis appeared severe on the basis of hematochemical examination results. On day 9 silibinin dihemisuccinate was replaced with silibinin betacyclodextrine per os. All patients were discharged on day 10-13. After two months all hematological parameters are in the normal range also a hepatobiliopancreatic echography does not show any morphological alteration. As in the case of polytherapies and because of the lack of comparative studies, it seems difficult to establish which therapeutic component had the major role in the resolution of the clinical picture. However, on the basis of our experience, and of the literature data, we think that silibinin may play a significant role in protecting hepatic tissue not yet injured. However we believe that other studies are necessary to confirm our hypothesis.

Cerebral white matter: technical development and clinical applications of effective magnetization transfer (MT) power concepts for high-power, thin-section, quantitative MT examinations

PURPOSE

To evaluate white matter disorders with magnetization transfer (MT) techniques.

MATERIALS AND METHODS

In 46 healthy volunteers and 46 clinical patients, MT Z spectra were obtained with various continuous-wave-equivalent MT powers (B1CW) and frequency offsets.

RESULTS

With B1CW of 270 Hz and 4,000-Hz frequency offset, the MT ratio of normal callosal white matter was 59.2% +/- 1.5 (standard deviation), with less than 5% contribution from direct saturation and spin locking. A small statistically significant (P < .01) regional variation in normal white matter was seen. Plaques in MS patients had a broad (or wide) range of MT ratios; normal appearing white matter had a slightly reduced MT ratio. Vasogenic edema had a minimal effect on MT ratio, and radiation necrosis showed prominent reductions in MT ratio.

CONCLUSION

High MT power techniques can expand the dynamic range of MT ratios, maintain a relatively pure MT effect, and be used effectively in MT imaging to evaluate white matter disorders.

Prognostic significance of necrosis, elastosis, fibrosis and inflammatory cell reaction in operable breast cancer

We analyzed retrospectively the relationships and the prognostic significance of four anatomopathological features (elastosis, fibrosis, necrosis, inflammatory cell reaction) of the primary tumor in a series of 1,457 cases of infiltrating ductal carcinoma observed at our institution from January 1978 to December 1991. Necrosis, elastosis, fibrosis and inflammatory cell reaction were strongly associated among themselves (all p < 0.0001), the only exception being necrosis and elastosis. Necrosis was significantly related to tumor size (odds ratio [OR] = 5.40, p < 0.0001) and tumor grade (OR = 2.22, p < 0.0001). Univariate analysis showed that the presence of necrosis and cell reaction were significantly related to worse survival (p < 0.0001 and p = 0.03, respectively). Multivariate analysis, including the four variables plus nodal status, tumor size, grading, adjuvant therapy, age and first order interactions, revealed that greater tumor size (p < 0.0001), positive nodal status (p < 0.0001), higher histologic grade (p < 0.0001) and presence of inflammatory cell reaction (p = 0.0007) independently worsened survival. On the other hand, adjuvant therapy had a significant independent role in preventing deaths (p = 0.03). The only first-order interaction retained in the model was that between grading and cell reaction (p = 0.002). Cell reaction had a different prognostic behaviour in the groups G1-G2 and G3: in the former group, survival was worse (p = 0.0001) when the inflammatory cell reaction was present. In conclusion, we demonstrate that cell reaction is an independent prognostic factor in the G1-G2 subgroup of patients, and propose a hypothesis as to the role of cell reaction in primary breast cancer.

Aniracetam improves behavioural responses and facilitates signal transduction in the rat brain

The effect of aniracetam (10, 50, 100 mg/kg i.p. daily for 15 days) on both behavioural and biochemical parameters was investigated in the adult rat. Animals given aniracetam (50 mg/kg 1 h before the trial) showed a significant increase in the percentage of conditioned active avoidance responses and a reduction of latency times. Aniracetam significantly counteracted the scopolamine-induced memory failure at the passive avoidance (step down) test, while it did not modify the locomotion of the animals. In purified frontocortical and hippocampal synaptic membranes of rats treated with aniracetam (50 mg/kg i.p. daily for 15 days) a potentiation of basal, carbamylcholine-, dopamine- and norepinephrine-stimulated adenylyl cyclase activity was observed, while forskolin-stimulated enzyme activity was not modified. With regard to inositol phosphate production measured in fronto-cortical synaptoneurosomes, aniracetam potentiated the stimulation by angiotensin II, while the stimulation by carbamylcholine, not affected by 10 and 50 mg/kg aniracetam, was notably, although not significantly, decreased by 100 mg/kg aniracetam. Furthermore, in synaptosomes derived from hippocampus, aniracetam (50 mg/kg i.p. daily for 15 days) caused an increase of both basal and K(+)-stimulated intrasynaptosomal Ca(2+) concentration. In conclusion, a correlation between the improvement of behavioural performance and the modulation of transducing systems by aniracetam seems to take place in brain areas, such as frontal cortex and hippocampus, known to play a major role in the control of cognitive functions.

Poly(ethylene oxide) (PEO) and different molecular weight PEO blends monolithic devices for drug release

An interpretation of the drug release from monolithic water-swellable and soluble polymer tablets is presented. A convenient parameter, alpha, which compares the drug-diffusive conductance in the gel layer with the swelling and dissolving characteristics of the unpenetrated polymer was used to describe the release behaviour of beta-hydroxyethyl-theophylline (etofylline) from compression-moulded tablets of hydrophilic pure semicrystalline poly(ethylene oxides) of mol wt 600,000 and 4,000,000 and of two blends of the two molecular weights of poly(ethylene oxides). The water swelling and dissolution characteristics of two polymers and two blends were analysed, monitoring the thickness increase of the surface-dissolving layer and the rates of water swelling and penetration in the tablets. The drug diffusivities in the water-penetrated polymer gels were measured by carrying out permeation tests. Finally, drug release tests were performed to investigate the release kinetics of the different systems in an aqueous environment at 37 degrees C. The drug release from the high molecular weight poly(ethylene oxide) is principally related to the material swelling rather than polymer dissolution, leading to a progressive decrease of the drug's diffusive conductance in the growing swollen layer, and hence to a non-constant release induced by the prevailing diffusive control. Conversely, drug release from the low molecular weight poly(ethylene oxide) is strictly related to the polymer dissolution mechanism. The achievement of stationary conditions, in which the rate of swelling equals the rate of dissolution, ensures a constant release rate, even in the case of very low drug-diffusive conductance in the external gel layer. Intermediate behaviours were detected in the case of the two blends.

Ki-67 and B72.3 expression in breast cancer: an immunohistochemical study

The present study was performed to evaluate Ki-67 and B72.3 immunostaining in 20 selected cases of breast cancer. In particular, we have examined the intracellular localization of TAG 72 and the tumour growth fraction, identified by Ki-67 antibody, on frozen sections of mammary carcinoma, by immunohistochemical technique (ABC method sec.Hsu). Immunostaining of TAG 72 and Ki-67 antigen was related to histologic subtype, diameter, nodal involvement, and number of positive axillary nodes. The preliminary results suggest that: (a) the presence of Ki-67 nuclear staining appeared to be associated with a poorer degree of differentiation, but no direct relationships were observed with diameter and nodal involvement; (b) no correlation between Ki-67 labelling rates and B72.3 intracytoplasmic immunostaining was observed; (c) myoepithelial cells show weak intracytoplasmic positivities.

Predominant left hemisphere metabolic dysfunction in dementia

Thirty-one patients with probable Alzheimer's disease and 11 patients with memory disorders, attributable to multiple cerebral infarctions, were studied using 18-F-fluorodeoxyglucose-positron emission tomography scans. Asymmetry in cerebral glucose metabolism within these diagnostic groups was assessed by comparison with the metabolic rates obtained in age-equivalent healthy control subjects. A significantly greater number of individuals in both patient groups exhibited predominant left rather than right hemisphere hypometabolism. In addition, for patients with Alzheimer's disease, the degree of asymmetry was not related to either the severity or duration of dementia. These findings could be explained by greater susceptibility of the left hemisphere to degenerative or ischemic brain disease, by a specific sampling effect, or most likely, by greater metabolic deficits resulting from left rather than right hemisphere impairment.

Two behavioral states studied in a single PET/FDG procedure: error analysis

In a previous publication the theory, procedure, and results of a method were described for making two sequential measurements of cerebral metabolic rate for glucose (CMRglc), within a 2-hr period, using [18F]fluorodeoxyglucose. The error that is specific to this technique was estimated using computer simulations. CMRglc for the second state was sensitive to errors in (a) the values of the rate constants, (b) alignment of PET slices between the two scans, and (c) subtraction of one PET image from another. The root mean square of the average error from each error source was 6.4%, which gives the theoretical reliability of this method. The measured reproducibility, taken from our previous publication, was 4.2-6.2%, which is in good agreement with the present result. This method contributes a small additional error above that expected for two independent scans. However, independent scans done on different days are likely to be subject to larger physiological variations in CMRglc than would occur using this method.

Sensitivity of cerebral glucose metabolism to age, gender, brain volume, brain atrophy, and cerebrovascular risk factors

In 76 normal volunteers studied by positron emission tomography, with [18F]fluorodeoxyglucose, CMRglu was significantly lower in the elderly as compared with young subjects and significantly higher in females relative to males. However, in 58 of these subjects who also had magnetic resonance imaging scans, age and gender were found to be unrelated to CMRglu, when the effects of brain volume and brain atrophy on CMRglu were partialed out using covariate analyses. Individually, brain volume was found to have a significant effect on CMRglu, explaining approximately 17% of the variability in CMRglu measures and brain atrophy explaining approximately 8% of the variance in CMRglu. Together these two measures accounted for approximately 21% of the variance. Cerebrovascular risk factors in normal subjects were not found to affect mean CMRglu or the variability of CMRglu measures. In this study almost 80% of the variance in CMRglu could not be explained by any of the factors that had been considered. This implies a lack of sensitivity of absolute values of global CMRglu to the mild effects of brain dysfunction. Although some of the unexplained variance is probably methodological in origin, physiological factors that are difficult to quantify, such as the state of arousal, are likely to be contributory as well.

Cerebral metabolic effects of a verbal fluency test: a PET scan study

Sixteen normal volunteers were studied with [F-18] fluorodeoxyglucose and positron emission tomography scans during behavioral activation with a verbal fluency test, and 35 age-matched controls were studied with resting-state scans. There was an overall increase of the cerebral glucose metabolic rate of 23.3% during verbal fluency activation, compared to the resting state, with the greatest activation in bilateral temporal and frontal lobes. A negative correlation between test performance scores and indices of metabolism was found in frontal, temporal, and parietal regions. Damage to the left frontal lobe maximally affects scores on verbal fluency tests, but performing the test activates a network of regions, of which the left frontal lobe is only one. Proficient performance in verbal fluency seems to require less metabolic activation than poor performance, perhaps because of the efficiency of cognitive strategies employed.

Behavioral activation and the variability of cerebral glucose metabolic measurements

Variability in cerebral glucose metabolism was examined between and within subjects when paired studies were performed in the resting state or in a behaviorally activated state. Both normal and demented subjects were studied twice each, from 1 to 6 weeks apart, under near-identical conditions, using positron emission tomography (PET) and [18F]fluorodeoxyglucose. Resting state studies were repeated in nine normal and four demented subjects. A picture-viewing test, used for activation during PET, was used repeatedly in seven normal and five demented subjects. Within-subject variability, as assessed by the percent difference in metabolic rates in paired studies, was reduced by 60-70% for activation state compared to resting state studies in normals. It is concluded that PET studies of brain metabolism, which are designed to study the active brain, should indeed be performed in functionally activated states, as in addition to demonstrating metabolism during a defined functional state, activation studies show reduced variability of cerebral metabolic measures.

Two behavioral states studied in a single PET/FDG procedure: theory, method, and preliminary results

We have developed a method that allows two sets of regional cerebral metabolic rates of glucose (rCMRglc) to be obtained in a single extended procedure using positron emission tomography (PET) and [18F]fluorodeoxyglucose (FDG). This is an adaptation of the deoxyglucose method, with the addition of a second injection of FDG immediately after completion of the first scan, then followed 30 min later by a second scan. A model has been developed to allow for correction of measured tracer concentration in the second scan by subtracting the predicted remnant from the first scan. The possible applications of this method in studying behavior-metabolism relationships are demonstrated. The preliminary results show 6%-12% changes in rCMRglc values for appropriate brain regions when the behavioral state is altered, but show 0%-5% change in rCMRglc values when the behavioral state is unchanged. The method can contribute significantly to the understanding of behavior-metabolism relationships by allowing the noninvasive study of two behavioral states in a single PET procedure.