Real-life use of ropeg-interferon α2b in polycythemia vera: patient selection and clinical outcomes.

Ropeginterferon-alfa2b (ropegIFNα2b) is a long-acting IFN formulation with broad FDA/EMA approval as a therapy of polycythemia vera (PV) with no symptomatic splenomegaly. There is currently lack of information on the real-world patient selection, including the impact of local reimbursement policies, and drug management, particularly: type/timing of screening and follow-up tests; absolute/relative contraindications to therapy; ropegIFNα2b dose and combinations with hydroxyurea. As a sub-analysis of the PV-ARC retrospective study (NCT06134102), we here report our monocenter experience with ropegIFNα2b in the period from January 2021, corresponding to drug availability outside clinical trial, and December 2023. Among the 149 patients with EMA/FDA indication, only 55 (36.9%) met the local reimbursement criteria and 18 (12.1%) received ropegIFNα2b. Thanks to appropriate screening, relative/absolute contraindications to ropegIFNα2b were detected and managed in a multidisciplinary manner. Efficacy and safety of ropegIFNα2b was confirmed, with 3 cases of early molecular response. General use of low ropegIFNα2b dose, with frequent need for hydroxyurea combinations, was noted. This real-world experience suggests a significant impact of local regulations on drug prescription and the need for greater real-world data collection on ropegIFNα2b in PV patients. Also, it describes appropriate multidisciplinary screening and monitoring procedures during ropegIFNα2b therapy.

Perioperative dental screening and treatment in patients undergoing cardiothoracic surgery and interventional cardiovascular procedures. A consensus report based on RAND/UCLA methodology.

AIM: To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures. METHODOLOGY: A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, a systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients, had never been defined. Following the systematic review, several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently, and then, a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures. RESULTS: A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered. CONCLUSIONS: Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus will become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.

Perioperative dental screening and treatment in patients undergoing cardio-thoracic surgery and interventional cardiovascular procedures. A consensus report based on RAND/UCLA methodology.

AIM: To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections, and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures. METHODOLOGY: A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients had never been defined. Following the systematic review several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently and then a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures. RESULTS: A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions, and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered. CONCLUSIONS: Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus can become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.

Nail dystrophies, scalp and intergluteal/perianal psoriatic lesions: risk factors for psoriatic arthritis in mild skin psoriasis?

AIM: In the literature, clinical features of psoriasis associated with psoriatic arthritis (PsA) onset have not been clarified, even if high Psoriasis Area and Severity Index (PASI) was found to be directly related with PsA. METHODS: The study was conducted between November 2008 and April 2009 on consecutive psoriatic outpatients referred to a service of dermatological consultations, on indication of other hospital specialists. Participants were affected by mild skin psoriasis, in particular with nail dystrophies and/or scalp and/or intergluteal/perianal lesions. The questionnaire provided by the Classification of Psoriatic Arthritis (CASPAR) study group was proposed to all patients and we added a question about the time of psoriasis onset. RESULTS: Eighty-seven subjects (34 males and 53 females) aged between 18 and 91 years (mean age 48 years) with such psoriatic features were recruited. Other 30 refused to take part to the study. Forty-seven per cent of these participants were found to suffer from PsA, in particular 83% of those with nail and scalp psoriasis, 40% of subjects with intergluteal/perianal involvement and 37% of patients with just scalp lesions. We present the first exploratory and observational study focused on a population with mild skin psoriasis, in order to evaluate if nail dystrophies, scalp or intergluteal/perianal psoriatic lesions might be indicative of a higher risk of PsA even in cases with mild skin psoriasis. CONCLUSION: Nail psoriasis is probably a suggestive feature of joint involvement. The scalp psoriasis, as well as intergluteal/perianal psoriatic lesions, is likely to be less associated to PsA, but may be an important comorbidity factor for the development of PsA. Further investigations in a larger population are encouraged to assess a potential link between PsA, site-specific and mild skin psoriasis.

Periungual pyogenic granulomas due to topical tazarotene for nail psoriasis.

Tazarotene is a topically-applied, receptor-selective retinoid that has been shown to modulate several major pathogenic factors of psoriasis. Adverse effects are those of topical application of retinoids, the most common being mild to moderate burning, itching, stinging, and erythema, due to mild to moderate local skin irritation. While pyogenic granuloma-like lesions are a well recognized side effects of systemic retinoids, to our knowledge in the literature there is only one reported case of pyogenic granuloma (PG) following topical application of tazarotene for scalp psoriasis. In this paper we report 2 cases of periungual PGs following application of topical tazarotene and we present a review of the literature.

A novel bispecific EGFR/Met antibody blocks tumor-promoting phenotypic effects induced by resistance to EGFR inhibition and has potent antitumor activity.

Simultaneous targeting of epidermal growth factor receptor (EGFR) and Met in cancer therapy is under pre-clinical and clinical evaluation. Here, we report the finding that treatment with EGFR inhibitors of various tumor cells, when stimulated with hepatocyte growth factor (HGF) and EGF, results in transient upregulation of phosphorylated AKT. Furthermore, EGFR inhibition in this setting stimulates a pro-invasive phenotype as assessed in Matrigel-based assays. Simultaneous treatment with AKT and EGFR inhibitors abrogates this invasive growth, hence functionally linking signaling and phenotype. This observation implies that during treatment of tumors a balanced ratio of EGFR and Met inhibition is required. To address this, we designed a bispecific antibody targeting EGFR and Met, which has the advantage of a fixed 2:1 stoichiometry. This bispecific antibody inhibits proliferation in tumor cell cultures and co-cultures with fibroblasts in an additive manner compared with treatment with both single agents. In addition, cell migration assays reveal a higher potency of the bispecific antibody in comparison with the antibodies' combination at low doses. We demonstrate that the bispecific antibody inhibits invasive growth, which is specifically observed with cetuximab. Finally, the bispecific antibody potently inhibits tumor growth in a non-small cell lung cancer xenograft model bearing a strong autocrine HGF-loop. Together, our findings strongly support a combination treatment of EGFR and Met inhibitors and further evaluation of resistance mechanisms to EGFR inhibition in the context of active Met signaling.

Trans-obturator colonic suspension during Altemeier's operation for full-thickness rectal prolapse: preliminary results with a new technique.

AIM: With the aim of reducing recurrence after perineal surgery for full-thickness rectal prolapse, a new operation consisting of a trans-obturator colonic suspension during Altemeier's operation has been developed. METHOD: Eighteen women with full-thickness rectal prolapse were examined clinically, with validated quality of life and continence scores, colonoscopy, anorectal manometry, anal EMG and sacral reflex latency. Ten had a newly diagnosed and eight a recurrent prolapse. The Altemeier operation was combined with a levatorplasty in all cases using two porcine collagen prostheses sutured to the descending colon and passed through the trans-obturator space bilaterally. The operation was completed by a manual or stapled colo-anal anastomosis. Clinical examination, with quality of life and continence scores, anorectal manometry, EMG and sacral reflex latency, was scheduled during follow up, with the recurrence of prolapse as the primary outcome measure. RESULTS: There were no recurrences at 30 months. There was no mortality and no complications. All patients experienced significant improvement in quality of life and faecal continence scores (P<0.01). Surgery did not affect anorectal pressures or sacral reflex latencies. CONCLUSION: The new technique appears to be relatively easy to perform and is complication free with no recurrence after a short period of follow up. A larger study with appropriate controls and longer follow up is now needed to assess its real effectiveness in reducing the risk of recurrence.

Immunohistochemical expression of p16(INK4A) protein in oral lichen planus.

The expression of p16(INK4A) has been investigated in oral leukoplakias (OLK), but no data are available about oral lichen planus (OLP). In this study, p16(INK4A) immunohistochemical expression was evaluated in 56 OLP and 36 OLK (12 without inflammation [NI-OLK] and 24 with chronic inflammation [I-OLK]) and compared with 23 reactive nonspecific inflammations (INF) and 14 normal control samples. The p16(INK4A) immunostaining was considered to be positive when >5% of keratinocytes were stained. All normal control samples were negative. Positive p16(INK4A) was detected in OLP, IOLK, and INF. Significant differences in p16(INK4A) positivity were found between OLP (64%) and OLK (28%) (χ(2) = 17.7; P < .01), and between I-OLK and NI-OLK (χ(2) = 4.5; P < .05). No significant difference was found between OLP and INF (43%). In conclusion, positive p16(INK4A) in OLP patients seems to be related to reactive inflammatory processes rather than to a risk of progression to oral squamous cell carcinoma.

Low-grade myofibroblastic sarcoma of the gingiva.

Low-grade myofibroblastic sarcoma is a malignant tumour from myofibroblasts, which has only recently become clearly defined. It represents a rare entity developing in the soft tissues of the head and neck. About 20 cases have been reported in the oral cavity, especially in the tongue and bone, while gingiva as the primary site has been described only once to date. Diagnostic methods include histology and immunohistochemistry. The present report concerns a case of a 37-year-old man who presented with a persistent gingival ulcerated swelling that was interpreted for a long time as a gingival epulis. A low-grade myofibrosarcoma was diagnosed and the patient underwent a segmental osteotomy of the mandibular symphisys for complete excision. There was no sign of recurrence or metastatic disease during the 18-month postoperative period.

Tuberculosis teaching in Brazilian medical schools.

To achieve tuberculosis (TB) control, National Tuberculosis Programme guidelines should be implemented effectively. In a survey conducted in 2005-2006, 33 Brazilian medical school coordinators answered a questionnaire about TB education. The median time dedicated to TB was 27 h (4-119 h), spread over several disciplines, mainly biological and clinical. This included 12 h (0-88 h) of practical activities, mainly in university hospitals (53%). The recommendation to offer human immunodeficiency virus testing for TB patients was taught in only 54% of the schools. TB education in Brazil is fragmented and restricted to a biological approach, while field activities are insufficient and carried out in inadequate settings. Important changes to the TB curriculum are necessary.

[Inguinal tension-free hernioplasty performed by day-care surgery in a non-specialized hospital]. / Ernioplastica inguinale tension-free praticata in regime di Day Surgery in un ospedale non dedicato.

BACKGROUND: At present, as a result of the introduction of tension-free techniques, the general opinion is that the treatment of inguinal hernia needs day-care surgery. Nevertheless day-care surgery requires a specific organization of the hospital and of the territorial services, after the discharge of the patient. These facilities are not always available all over the country. The aim of this paper is to present the results of the treatment of inguinal hernia performed by day-care surgery in an unspecialized hospital. METHODS: From April 1999 to April 2000, 28 patients (25 M), median age 54 years (range 25-85), affected by inguinal hernia, underwent ernioplasty operation according to Trabucco technique, by only one skilled surgeon, in an unspecialized hospital. Five patients were affected by inguinal hernia of type I of Nyhus, 9 of type II, 10 of type IIIa and 4 of type IIIb. Twenty-five patients underwent spinal anaesthesia and 3 general anaesthesia due to failure of the previous one or for contraindications due to spine diseases or due to patient's request. All patients remained in the hospital the night after the operation. After discharge, patients were controlled in the outpatient ambulatory every other day for 10 days. After that, patients were required to submit to physical examination only if they were symptomatic. At present, average follow-up is of 18.1+/-6.3 months. RESULTS: The following unspecific complications prevalently due to spinal anaesthesia were observed: 2 (7.1%) acute urinary retentions, 1 (3.6%) headache, 1 (3.6%) acute hypotension, 2 (7.1%) feverets, 1 (3.6%) vomiting, and 1 (3.6%) influenza. The specific complications were: 2 (7.1%) transient neuralgias, 2 (7.1%) ecchimosis and 1 (3.6%) infection of the wound. Average intensity of postoperative pain (VAS) was of 2.8+/-1.2. The average abstention from work was of 12.5 days. Until now, any recurrence has been observed. CONCLUSIONS: In spite of the few cases, our results are similar to those of specialized hospitals organized for day-care surgery. Anyway, in the management of these patients in unspecialized hospitals, according to our opinion one night in the hospital after the operation is required for the easiness of the patient and of the surgeon.

Selection criteria and long-term results of surgery in symptomatic rectocele.

BACKGROUND: The aim of this study was to confirm some selection criteria for the transrectal repair of the anterior rectocele and to compare our surgical results with those reported in the literature. METHODS: From January 1992 to December 1999, 30 females (mean age 52.9 years, range 28-70 yrs) affected by anterior rectocele were prospectively evaluated with a standard questionnaire, clinical examination, proctosigmoidoscopy, colonic transit time, dynamic defecography, anal EMG, anal manometry. Then, they were submitted to transrectal repair of rectocele with anterior plication of the rectal muscular wall. Fourteen (46.6%) of them were also submitted to perineal levatorplasty. Patients were followed postoperatively (mean 25.7 months) with the same standard questionnaire, clinical examination, defecography, and manometry. Results were tested by Fisher's Exact text, Wilcoxon's test, and "t"-test. RESULTS: Rectal dyschezia, incomplete evacuation, digital help in defecating, mean stool frequency, and rectal bleeding significantly improved. After 3 months, 30% of patients had no complaints, 40% had only 1-2 episodes/month complaints, 13.3% had evacuation only using laxatives, and 16.6% were unchanged. Defecography showed a significant reduction of the rectocele in 70% of patients after 3 months. Manometric parameters were not significantly modified. Four (28.6%) out of 14 patients submitted to perineal levatorplasty complained of dyspareunia. CONCLUSIONS: Our surgical results were comparable with those reported in the literature, with more than 80% of successful outcome. Preoperative clinical data and defecography were confirmed to be basic parameters in selecting patients for surgery. Colonic transit time, anal EMG, and anorectal manometry demonstrated to be useful to recognize conditions as slow colonic transit time, peripheral denervation, and reduced voluntary contraction that could lead to a less satisfactory outcome after surgery, and might benefit with a postoperative perineal rehabilitation by biofeedback and anal electrostimulations. The perineal levatorplasty is not suitable in young females, due to the risk of dyspareunia.

Randomised controlled trial between stapled circumferential mucosectomy and conventional circular hemorrhoidectomy in advanced hemorrhoids with external mucosal prolapse.

BACKGROUND: This randomized prospective study compared the outcome of circular hemorrhoidectomy according to the Hospital Leopold Bellan (HLB) technique (Paris) with Longo stapled circumferential mucosectomy (LSCM) in two homogeneous groups of patients affected by circular fourth-degree hemorrhoids with external mucosal prolapse. METHODS: From December 1996 to December 1999, 80 consecutive patients with fourth-degree hemorrhoids and external mucosal prolapse were randomly assigned to two groups. Forty patients (group A: 18 men, 22 women, mean age 50.5 years, range 21 to 82) underwent HLB hemorrhoidectomy, and 40 patients (group B: 15 men, 25 women, mean age 51.0 years, range 29 to 92) underwent LSCM. Before surgery, all patients were selected with a standard questionnaire for symptom evaluation, full proctological examination, flexible rectosigmoidoscopy, dynamic defecography, and anorectal manometry. No significant differences among the two groups were found. All patients were controlled with follow-up questionnaire and with clinical examination at 1, 2, 4, 12, and 54 weeks after the operation. A postoperative manometry was performed 3 months after surgery. RESULTS: The length of the operation was significantly lower in group B (25 +/- 3.1 SD versus 50 +/- 5.3 minutes, P <0.001). Mean hospital stay was 3 +/- 0.4 days in group A and 2 +/- 0.5 days in group B (P <0.01). Mean duration of inability to work was 8 +/- 0.9 days in group B and 15 +/- 1.4 days in group A (P <0.001). Postoperative pain was significantly lower in group B (P <0.001). Mean length of follow-up was 20 +/- 8.0 months in group A and 20 +/- 7.8 months in group B. Late complications were similar in the two groups, with 0%, at present, recurrence rate. CONCLUSIONS: Our results confirm that both operations are safe, easy to perform, and effective in the treatment of advanced hemorrhoids with external mucosal prolapse. However, the LSCM seems to be preferable owing to the fewer postoperative complications, easier postoperative management, and shorter time to return to work. A longer follow-up is required to confirm the true efficacy of this surgical method.

Oligomerization of NhaA, the Na+/H+ antiporter of Escherichia coli in the membrane and its functional and structural consequences.

Recently, a two-dimensional crystal structure of NhaA, the Na+/H+ antiporter of Escherichia coli has been obtained [Williams, K. A., Kaufer, U. G., Padan, E., Schuldiner, S. and Kühlbrandt, W. (1999) EMBO J., 18, 3558-3563]. In these crystals NhaA exists as a dimer. Using biochemical and genetic approaches here we show that NhaA exists in the native membrane as a homooligomer. Functional complementation between the polypeptides of NhaA was demonstrated by coexpression of pairs of conditional lethal (at high pH in the presence of Na+) mutant alleles of nhaA in EP432, a strain lacking antiporters. Physical interaction in the membrane was shown between the His-tagged NhaA polypeptide which is readily affinity purified from DM-solubilized membranes with a Ni2+-NTA column and another which is not; only when coexpressed did both copurify on the column. The organization of the oligomer in the membrane was studied in situ by site-directed cross-linking experiments. Cysteine residues were introduced--one per NhaA--into certain loops of Cys-less NhaA, so that only intermolecular cross-linking could take place. Different linker-size cross-linkers were applied to the membranes, and the amount of the cross-linked protein was analyzed by mobility shift on SDS-PAGE. The results are consistent with homooligomeric NhaA and the location of residue 254 in the interface between monomers. Intermolecular cross-linking of V254C caused an acidic shift in the pH profile of NhaA.

Which surgical approach for rectocele? A multicentric report from Italian coloproctologists.

The most effective surgical technique for rectocele has not yet been clearly established. A retrospective multicentric study was carried out to compare the long-term results of 3 endorectal techniques (Block, Sarles and stapled) and the perineal levatorplasty, alone and in association, in a series of patients with symptomatic rectocele. From January 1992 to December 1999, 2212 patients with defecation disorders were referred to 5 Italian coloproctology units. An anterior rectocele was clinically diagnosed in 1045 patients and confirmed with defecography. On the basis of clinical and radiological parameters, 317 patients (312 women; mean age, 52.4+/-20.1 years) were selected for surgery. Group 1 consisted of 141 patients (136 women; mean age, 50.4+/-18.8 years) who were submitted to endorectal operations. Group 2 consisted of 126 women (mean age, 52.5+/-19.7 years) who received perineal levatorplasty. Finally, 50 women (mean age, 54.3+/-21.9 years) in Group 3 received endorectal operations associated with perineal levatorplasty. A total of 269 patients were followed postoperatively (mean period, 24.2+/-3.1 months, 27.5+/-5.4 months and, 22.8+/-2.8 months, respectively) with the same questionnaire and clinical examination. Three months after surgery, a defecography examination and anorectal manometry were performed in 136 and 132 patients, respectively. Operative time, hospital stay and time to return to work were significantly higher in Group 3 (p<0.001). There was one death in Group 3 due to severe sepsis. Main postoperative complications were: in Group 1, hemorrhage (7.8%, all Sarles), dehiscence of the endorectal suture (5.0%, all Block), distal rectal stenosis (2.1%, 1 stapled, 2 block), and rectovaginal fistula (1.4%, all Sarles); in Group 2, delayed healing of the perineal wound (16.4%); in Group 3 delayed healing of the perineal wound (22.0%), hemorrhage (6%, all Sarles), dehiscence (4.0%), stenosis (2.0%). 17.3% of patients of Group 2 and 22.5% of Group 3 complained of dyspareunia. Postoperative defecography showed a complete absence of the rectocele in 44.1% of patients and reduction of size in the others, without significant differences among the three groups. Manometric pattern was not significantly modified by surgery. Significant symptoms recurred in 5.9% of the patients in Group 1, 6.4% in Group 2, and 5.0% in Group 3. Perineal levatorplasty did not significantly improve obstructed defecation, as it did not allow to excise the rectal mucosal prolapse, and was followed by an high incidence of delayed healing of the perineal wound and dyspareunia. Sarles procedure achieved better control of mucosal prolapse but carried a higher complication rate compared to the others. The association of the perineal levatorplasty with an endorectal technique required significantly longer operative time, and led to a longer hospital stay and time to return to work. In conclusion, the investigated techniques showed different patterns of postoperative complications: bleeding after Sarles, dehiscence after Block, dyspareunia after perineoplasty and fatal gangrene after stapled, but non of them showed a clear superiority over the others in term of clinical or functional results 2 years after surgery.

A photochemically driven molecular-level abacus

A molecular-level abacus-like system driven by light inputs has been designed in the form of a [2]rotaxane, comprising the pi-electron-donating macrocyclic polyether bis-p-phenylene-34-crown-10 (BPP34C10) and a dumbbell-shaped component that contains 1) a Ru(II) polypyridine complex as one of its stoppers in the form of a photoactive unit, 2) a p-terphenyl-type ring system as a rigid spacer, 3) a 4,4'-bipyridinium unit and a 3,3'-dimethyl-4,4'-bipyridinium unit as pi-electron-accepting stations, and 4) a tetraarylmethane group as the second stopper. The synthesis of the [2]rotaxane was accomplished in four successive stages. First of all, the dumbbell-shaped component of the [2]rotaxane was constructed by using conventional synthetic methodology to make 1) the so-called "west-side" comprised of the Ru(II) polypyridine complex linked by a bismethylene spacer to the p-terphenyl-type ring system terminated by a benzylic bromomethyl function and 2) the so-called "east-side" comprised of the tetraarylmethane group, attached by a polyether linkage to the bipyridinium unit, itself joined in turn by a trismethylene spacer to an incipient 3,3'-dimethyl-4,4'-bipyridinium unit. Next, 3) the "west-side" and "east-side" were fused together by means of an alkylation to give the dumbbell-shaped compound, which was 4) finally subjected to a thermodynamically driven slippage reaction, with BPP34C10 as the ring, to afford the [2]rotaxane. The structure of this interlocked molecular compound was characterized by mass spectrometry and NMR spectroscopy, which also established, along with cyclic voltammetry, the co-conformational behavior of the molecular shuttle. The stable translational isomer is the one in which the BPP34C10 component encircles the 4,4'-bipyridinium unit, in keeping with the fact that this station is a better pi-electron acceptor than the other station. This observation raises the question- can the BPP34C10 macrocycle be made to shuttle between the two stations by a sequence of photoinduced electron transfer processes? In order to find an answer to this question, the electrochemical, photophysical, and photochemical (under continuous and pulsed excitation) properties of the [2]rotaxane, its dumbbell-shaped component, and some model compounds containing electro- and photoactive units have been investigated. In an attempt to obtain the photoinduced abacus-like movement of the BPP34C10 macrocycle between the two stations, two strategies have been employed-one was based fully on processes that involved only the rotaxane components (intramolecular mechanism), while the other one required the help of external reactants (sacrificial mechanism). Both mechanisms imply a sequence of four steps (destabilization of the stable translational isomer, macrocyclic ring displacement, electronic reset, and nuclear reset) that have to compete with energy-wasteful steps. The results have demonstrated that photochemically driven switching can be performed successfully by the sacrificial mechanism, whereas, in the case of the intramolecular mechanism, it would appear that the electronic reset of the system is faster than the ring displacement.

Role of iodine in evolution and carcinogenesis of thyroid, breast and stomach.

The authors have hypothesized that dietary iodine (deficiency or excess) is associated with the development of some gastric and mammary cancers, as it is well-known for thyroid cancer. They report a short review of their own work and of the general literature on this correlation and on the antioxidant function of iodide in stomach, breast and thyroid. Thyroid cells phylogenetically derived from primitive iodide-concentrating gastroenteric cells which, during evolution, migrated and specialized in uptake and storage of iodine, also in order to adapt the organisms from iodine-rich sea to iodine-deficient land. Mammary cells also derived from primitive iodide-concentrating ectoderm. Stomach, breast and thyroid share an important iodide-concentrating ability and an efficient peroxidase activity, which transfers electrons from iodides to the oxygen of hydrogen peroxide and so protects the cells from damage caused by lipid peroxidation. The authors suggest that iodide might have an ancestral antioxidant function in all iodide-concentrating cells from primitive Algae to more recent Vertebrates. In Italy, gastric cancer is more frequent in farmers and in iodine-deficient populations, living in mountainous and hilly areas, than in fishermen. In the last two decades, Italian decrease of gastric cancer seems to be correlated more to the higher dietary consumption of iodine-rich fish rather than to consumption of fruit and vegetables, which indeed has decreased in Italy.