Be(a)ware of spider! An attentional blink study on fear detection

We investigated whether detection of fearful stimuli is independent from attention by using an iconic version of the Attentional Blink Task in arachnophobic individuals. A colored animal icon (Target) and a black spider or butterfly icon (Probe) appeared in close temporal proximity within a stream of distractors, at one of 4 possible time lags. In one task, Probe detection was required; in another one, Target identification was also requested. In this case, competition for attentional resources produces the so-called AB effect, that is the decrease of Probe perception as a function of lag. During spider-Probe detection, arachnophobics showed a reduced AB effect with respect to the butterfly-Probe session. Their spider detection scores were also greater than ratings obtained by non-phobic controls with both Probe types. Thus, fear appears to enhance the probability of consciously perceiving the stimulus even when attention is engaged by a previous demanding event. One may assume that spider-Probe is scarcely attention demanding because detection of threat in arachnophobics is increased by rapid amygdala activation of visual areas and/or facilitated by a strong arousal-induced noradrenergic cortical input. Alternatively, an attention capturing mechanism involuntary triggered by the phobic meaning of the stimulus could be hypothesized.

Gastrointestinal perforations following kidney transplantation

This study reports major gastrointestinal (GI) complications among a group of 1611 patients following kidney transplantation. The immunosuppressive regimen changed somewhat during the course of the study but included azathioprine, prednisolone, antilymphocyte globulin, cyclosporine, tacrolimus, mycophenolate mofetil, and sirolimus. Perforations occurred in the colon (n=21), small bowel (n=15), duodenum (n=6), and stomach (n=4). Nearly 50% of the complications occurred while patients were being given high-dose immunosuppression to manage either the early postoperative period or acute rejection episodes. Of the 46 patients affected, 11 (24%) died as a direct result of the GI complication. This high mortality appeared to be related to the effects of the immunosuppression and the associated response to sepsis. Reduction of these complications may be achieved by improved surgical management, preventive measures, prompt diagnosis, and a reduced immunosuppressive protocol.

Hernia repair with porcine small-intestinal submucosa

PURPOSE

Although at present nonabsorbable meshes are the preferred material for tension-free hernioplasty, some problems with their use have yet to be addressed (i.e., chronic pain and infections). In order to address these disadvantages, a collagen-based material, the porcine small-intestinal submucosa mesh (Surgisis Inguinal Hernia Matrix, Cook Surgical, Bloomington, IN, USA), has recently been developed for hernia repair.

METHODS

With the aim of investigating the clinical safety and effectiveness of Surgisis IHM inguinal hernia repair, we report our experience of 45 consecutive hernioplasties with a medium-term follow-up. The surgical technique for the use of this material in hernioplasty is described in detail.

RESULTS

Although some local (i.e., seromas) and general (i.e., hyperpyrexia), complications appeared in the immediate postoperative period (all of them disappeared spontaneously), no rejection or infection was observed after operations. At the 2-year follow-up, a low degree of pain and discomfort and no recurrences were observed.

CONCLUSIONS

We conclude that the Surgisis IHM hernioplasty is feasible with promising results and, from a clinical perspective, seems safe and effective.

Hypnotizability and spatial attentional functions

Many theories of hypnotic responding have proposed that differences in hypnotic trait rely on differences in frontal attentional functions. Evidence of hypnotizability-related attentional abilities are, however, very scant. This study was designed to investigate the relationship between hypnotizability and executive control components of attention in the spatial domain. We chose the Attention Network Test that enables to analyze alerting, orienting and executive control functions by measuring reaction times (RTs) to targets cued for different locations in space. According to Posner theory, alerting, orienting and executive control effects were found in both groups. No differences between highly susceptible (Highs) and low susceptible individuals (Lows) on executive control functions were found. However, in Highs alerting was significantly smaller than in Lows and Highs were significantly faster than Lows in the no and central cue conditions. These findings suggest that Highs would be endowed with a basal higher efficiency in achieving and maintaining their readiness to respond to incoming stimuli. This relation between hypnotizability and alerting, is discussed in terms of a possible more efficient noradrenergic activity driven by frontal attentional systems.

Use of porcine dermal collagen graft (Permacol) for hernia repair in contaminated fields

BACKGROUND

Complicated hernias often involve contaminating surgical procedures in which the use of polypropylene meshes can be hazardous. Prostheses made of porcine dermal collagen (PDC) have recently been proposed as a means to offset the disadvantages of polypropylene meshes and have since been used in humans for hernia repairs. The aim of our study was to evaluate the safety and efficacy of incisional hernia repair using PDC as a mesh in complicated cases involving contamination.

METHODS

A prospective study of hernia repair of complicated incisional hernias with contamination using PDC grafts was carried out at the Department of General, Emergency and Transplant Surgery of St Orsola-Malpighi University Hospital.

RESULTS

From January 2004 up to the writing of this article, seven patients were treated for complicated incisional hernias with a PDC prosthesis. In six out of seven patients a bowel resection was carried out. There were not surgical complications. Morbidity was 14.2%. No recurrences and wound infections were observed.

CONCLUSIONS

Incisional hernioplasty using PDC grafts is a potentially safe and efficient approach in complicated cases with contamination.

A positive feedback loop between hepatocyte growth factor receptor and beta-catenin sustains colorectal cancer cell invasive growth

Overexpressed or activated hepatocyte growth factor receptor, encoded by the MET proto-oncogene, was found in the majority of colorectal carcinomas (CRCs), whose stepwise progression to malignancy requires transcriptional activation of beta-catenin. We here demonstrate that a functional crosstalk between Met and beta-catenin signaling sustains and increases CRC cell invasive properties. Hepatocyte growth factor (HGF) stimulation prompts beta-catenin tyrosine phosphorylation and dissociation from Met, and upregulates beta-catenin expression via the phosphatidylinositol 3-kinase pathway in conditions that mimic those found by the invading and metastasizing cells. Additionally, a transcriptionally active form of beta-catenin, known to be oncogenic, enhances Met expression. Furthermore, HGF treatment increases the activity of the beta-catenin-regulated T-cell factor transcription factor in cells expressing the wild-type or the oncogenic beta-catenin. In the mirror experiments, either Met or beta-catenin knocking down also reduces their protein level. In biological assays, beta-catenin knocking down abrogates the HGF-induced motile phenotype, whereas active beta-catenin fosters ligand-independent cell scattering. Met and beta-catenin also cooperate in promoting entry into the cell cycle and in protecting cells from apoptosis. In conclusion, Met and beta-catenin pathways are mutually activated in CRC cells. This might generate a self-amplifying positive feedback loop resulting in the upregulation of the invasive growth properties of CRC cells.

Lichtenstein repair of inguinal hernia with Surgisis inguinal hernia matrix soft-tissue graft in immunodepressed patients

While polypropylene mesh remains the preferred prosthesis material for hernioplasties, there are some problems with infections, intestinal obstruction and fistulization, and migration particularly in immunodepressed patients. A new degradable and reabsorbable material, the porcine small intestinal submucosa (Surgisis) has been developed for hernia repairs in humans. This prospective study evaluated the safety and efficacy of Lichtenstein hernioplasty using the Surgisis inguinal hernia matrix soft-tissue graft as a mesh in ten immunodepressed subjects. Six subjects were HIV-positive in the immunodepressive phase, and the other four had undergone transplantation (three kidney, one liver). There were no intraoperative or postoperative complications, recurrences, or wound infections. Thus Lichtenstein's hernioplasty using the Surgisis inguinal hernia matrix soft-tissue graft in immunodepressed patients promises safety and efficacy.

[Volvulus of the gallbladder]

The gallbladder volvulus is a very rare but extremely dangerous event. Described for the first time by Wendel in 1898, it affects more frequently the female sex, particularly in old age. The clinical case of a patient affected by this pathology, personally observed, is presented and the initial symptoms, diagnostic procedures and surgical intervention are described in detail. The anatomical and physiological backgrounds that permit the gallbladder to twist on its axis are analysed and finally the importance of an early diagnosis to avoid the complications of a bilious peritonitis is underlined. In any case the definite diagnosis is made more frequently during surgical intervention. An early intervention allows a rapid resolution of the clinical picture preventing the perforation of the viscus into the peritoneal cavity and the complication of a bilious peritonitis besides the spreading of the biliary stones into the abdominal cavity.

Uroporphyrinogen decarboxylase: complete human gene sequence and molecular study of three families with hepatoerythropoietic porphyria

A deficiency in uroporphyrinogen decarboxylase (UROD) enzyme activity, the fifth enzyme of the heme biosynthetic pathway, is found in patients with sporadic porphyria cutanea tarda (s-PCT), familial porphyria cutanea tarda (f-PCT), and hepatoerythropoietic porphyria (HEP). Subnormal UROD activity is due to mutations of the UROD gene in both f-PCT and HEP, but no mutations have been found in s-PCT. Genetic analysis has determined that f-PCT is transmitted as an autosomal dominant trait. In contrast, HEP, a severe form of cutaneous porphyria, is transmitted as an autosomal recessive trait. HEP is characterized by a profound deficiency of UROD activity, and the disease is usually manifest in childhood. In this study, a strategy was designed to identify alleles responsible for the HEP phenotype in three unrelated families. Mutations of UROD were identified by direct sequencing of four amplified fragments that contained the entire coding sequence of the UROD gene. Two new missense mutations were observed at the homoallelic state: P62L (proline-to-leucine substitution at codon 62) in a Portuguese family and Y311C (tyrosine-to-cysteine substitution at codon 311) in an Italian family. A third mutation, G281E, was observed in a Spanish family. This mutation has been previously described in three families from Spain and one from Tunisia. In the Spanish family described in this report, a paternal uncle of the proband developed clinically overt PCT as an adult and proved to be heterozygous for the G281E mutation. Mutant cDNAs corresponding to the P62L and Y311C changes detected in these families were created by site-directed mutagenesis. Recombinant proteins proved to have subnormal enzyme activity, and the Y311C mutant was thermolabile.

Incidence of hereditary porphyria cutanea tarda (PCT) in a sample of the Italian population

The determination of the enzymatic activity of URO-D in erythrocytes is the screening method used for differentiation between hereditary and non-hereditary forms of porphyria cutanea tarda (PCT). The aim of the present work was to establish the relative frequencies of the symptomatic and hereditary forms by the determination of the URO-D enzyme in the PCT patients who were regularly treated at the Centre for Porphyrins in our Institute. In the course of this work we also examined the statistical properties of the distributions of both normal and porphyric subjects, so as to be able to suggest values for discriminating between normal subjects and the various types of porphyric subjects.

Parathyroid gastrin and parathormone-producing tumour in the Zollinger-Ellison syndrome of MEN 1 origin

A case of Zollinger-Ellison syndrome of multiple endocrine neoplasia type 1 (MEN 1) origin with hyperparathyroidism and with a rise in serum gastrin due to an unusual parathyroid "gastrinoma" has been investigated. The patient had multiple endocrine tumours (pituitary and parathyroid), but no evidence of pancreatic or duodenal gastrin-producing neoplasm. Radio-immunoassay, immunohistochemistry and electron microscopy showed gastrin in one parathyroid adenoma. These findings, together with a decrease of gastrinaemia after parathyroidectomy suggest that true gastrin was produced by parathyroid tumour cells and that they themselves may be the origin of the hypergastrinaemia. Our ultrastructural investigation extends these observations and the results are discussed.

Neurogenic intrathoracic tumors. A clinicopathological review of 92 cases

Ninety-two cases of intrathoracic neurogenic tumors operated on between 1950 and 1982 are reviewed. The benign forms (86 cases, 93.5%) included 23 ganglioneuromas, 50 neurilemmomas and 13 neurofibromas. Of the latter, 4 occurred in patients with Von Recklinghausen's disease. A double local recurrence was observed after the removal of a neurilemmoma. One of the patients with generalized neurofibromatosis died 5 months after operation from local sarcomatous degeneration and distant metastases. In this group of benign lesions, no other death was observed which could be attributed to the endothoracic neural tumor. The malignant forms (6 cases, 6.5%) included 4 ganglioneuroblastomas and 2 neurofibrosarcomas. The surgical excisions were described as radical in every case and all the patients were given radiotherapy postoperatively. One patient with ganglioneuroblastoma died from metastases 2 years later, and one with neurofibrosarcoma from local recurrences 7 months later. One patient with neurofibrosarcoma and 3 with ganglioneuroblastomas are alive and well 4, 5, 6 and 11 years, respectively, later. Surgical excision remains the best method of diagnosing and treating endothoracic tumors of neural origin. Of special interest are the "dumbbell" or hourglass tumors and lesions which occur in Von Recklinghausen's disease.

Action of antithymocyte globulin on normal human erythroid progenitor cell proliferation in vitro: erythropoietic growth-enhancing factors are released from marrow accessory cells

Studies were undertaken to determine the mechanism of action of a horse antithymocyte globulin preparation (ATGAM) (HATG) and its control preparation of horse gamma globulin (HIgG) on the proliferation of normal human marrow and blood erythroid progenitor cells (CFU-E, BFU-E) in vitro. In preincubation studies with marrow mononuclear cells and complement, HATG did not significantly augment CFU-E or BFU-E growth greater than that expected because of removal of marrow T cells by this agent. However, direct addition of HATG but not HIgG to marrow cultures significantly stimulated CFU-E and BFU-E up to two to four times that of media or HIgG controls (P less than 0.05). The peak effect was observed at 10 to 100 micrograms/ml HATG; HATG was toxic at 1000 micrograms/ml. By contrast, the OKT3 monoclonal antibody was less stimulatory than HATG. The in vitro erythropoietic stimulatory effect of HATG was dependent on the presence of accessory cells because removal of T cells or monocytes (less than 2% to 5%) or adsorptions of HATG with T cells or monocytes reduced its stimulatory effect, highly purified BFU-E nearly devoid of accessory cells required irradiated accessory cells for demonstration of the HATG stimulatory effect, and an erythroid burst-promoting activity was released from T cells or unseparated mononuclear cells in the presence of HATG but not HIgG. The HATG enhancing effect was optimal in the first 96 hours of cultures in the presence of erythropoietin, and was reproducible with three separate lots of HATG. Up to 16% of HATG-stimulated erythroid colonies expressed nonerythroid lineage cells. Iron 59 incorporation into heme of CFU-E- or BFU-E-derived colonies was augmented equally by HATG or HIgG at 10 micrograms/ml. Erythropoietin dose-response curves and studies with antierythropoietin sera suggested that HATG also increased the sensitivity of erythroid progenitor cells to very low concentrations of erythropoietin. We conclude that HATG but not HIgG control has potent dose-dependent erythroid progenitor cell growth-enhancing effects. In addition to the ability of HATG to lyse T-suppressor cells, these findings suggest that HATG may also stimulate erythropoiesis indirectly by releasing growth-enhancing factor(s) from T cells and other marrow accessory cells, sensitizing erythroid progenitor cells to low concentrations to erythropoietin, and stimulating growth of bipotential progenitor cells. Collectively, these effects may explain the efficacy of HATG in the treatment of some patients with erythropoietic marrow failure states.

Hypoplastic anemia in B cell chronic lymphocytic leukemia: evolution of T cell-mediated suppression of erythropoiesis in early-stage and late-stage disease

To define further the role of marrow T suppressor lymphocytes in the pathogenesis of the hypoproliferative anemia in all Rai clinical stages of B cell chronic lymphocytic leukemia (CLL), marrow erythroid progenitor cell (CFU-E and BFU-E) frequency, marrow T gamma lymphocyte frequency per 1,000 nucleated marrow cells, and T cell-erythroid progenitor cell interactions were examined in 30 CLL patients and normal control subjects. As compared with control subjects, decreased numbers of CFU-E and BFU-E were found in patient marrow depleted of neoplastic B cells in all Rai stages of the disease. As a group, Rai stage III through IV patients with or without aplasia (CLL-aplasia) had significantly fewer CFU-E and BFU-E than did Rai O through II stage patients. The numbers of T gamma cells infiltrating CLL marrows were increased 3, 9, and 20 times normal in Rai O through II, Rai III through IV, and CLL-aplasia groups, respectively. Removal of T cells from marrow increased growth of CFU-E and BFU-E in all Rai O through IV patients, but the increase was significant in the CLL-aplasia group only (P less than .05). However, autologous coculture of marrow T cells or T gamma cells but not B cells with marrow B + T-depleted null cells at ratios of 0.2:1 to 1:1 suppressed CFU-E and BFU-E growth in all three patient groups. We conclude that the hypoproliferative anemia occurring in the course of B cell CLL is due to gradual accumulation in the marrow of T gamma lymphocytes which suppress erythroid progenitor cell growth. T gamma cell suppression of erythropoiesis and marrow T gamma cell expansion is detectable in the earliest Rai stages of the disease.

Hereditary coproporphyria: unusual nervous system involvement in two cases

Two cases of hereditary coproporphyria showed unusual nervous system involvement, one epilepsy with onset in childhood, and the other chronic central and peripheral nervous system damage. The literature is briefly discussed.

Dermatomyositis-like syndrome due to toxoplasma

A woman had the typical clinical, cutaneous, and muscular picture of dermatomyositis but without some of the biochemical alterations of that disease. The positive serological investigations for toxoplasmosis, the pressure in muscles of very numerous toxoplasms and their culture in mice, and the improvement after treatment with pyrimethamine and sulphametoxypyridine demonstrated that the signs of dermatomyositis had been caused by infection with toxoplasmosis.