Threat learning in space: How stimulus-outcome spatial compatibility modulates conditioned skin conductance response

A central question in Pavlovian conditioning concerns the critical conditions that drive the acquisition and maintenance of the stimulus-outcome association. The spatial relationship between the conditioned (CS) and unconditioned (US) stimuli is considered to exert strong effects on learning. However, how spatial information modulates Pavlovian learning remains mostly unexplored in humans. Here, we test how the compatibility between the CS and the US location influences the acquisition, extinction, and recovery (following reinstatement) of Pavlovian conditioned threat. Participants (N = 20) completed a differential threat conditioning task in which visual CSs appeared on the same (compatible) or opposite (incompatible) hemispace as the US delivery (aversive shock to one hand), while their skin conductance response served as an index of learning. Results show that initial threat expectations were biased in favor of compatible CSs before conditioning. Nevertheless, this bias was revised during acquisition to reflect current stimulus-outcome contingencies. Computational modeling suggested that this effect occurred through a higher reliance on positive aversive prediction errors for incompatible CSs, thereby facilitating learning of their association with the US. Additionally, the conditioned response to incompatible CSs was associated with initially slower extinction and a greater recovery after threat reinstatement. These findings suggest that spatial information conveyed by stimuli and outcomes can be flexibly used to enact defensive responses to the current source of danger, highlighting the adaptive nature of Pavlovian learning.

Microglial diversity along the hippocampal longitudinal axis impacts synaptic plasticity in adult male mice under homeostatic conditions

The hippocampus is a plastic brain area that shows functional segregation along its longitudinal axis, reflected by a higher level of long-term potentiation (LTP) in the CA1 region of the dorsal hippocampus (DH) compared to the ventral hippocampus (VH), but the mechanisms underlying this difference remain elusive. Numerous studies have highlighted the importance of microglia-neuronal communication in modulating synaptic transmission and hippocampal plasticity, although its role in physiological contexts is still largely unknown. We characterized in depth the features of microglia in the two hippocampal poles and investigated their contribution to CA1 plasticity under physiological conditions. We unveiled the influence of microglia in differentially modulating the amplitude of LTP in the DH and VH, showing that minocycline or PLX5622 treatment reduced LTP amplitude in the DH, while increasing it in the VH. This was recapitulated in Cx3cr1 knockout mice, indicating that microglia have a key role in setting the conditions for plasticity processes in a region-specific manner, and that the CX3CL1-CX3CR1 pathway is a key element in determining the basal level of CA1 LTP in the two regions. The observed LTP differences at the two poles were associated with transcriptional changes in the expression of genes encoding for Il-1, Tnf-α, Il-6, and Bdnf, essential players of neuronal plasticity. Furthermore, microglia in the CA1 SR region showed an increase in soma and a more extensive arborization, an increased prevalence of immature lysosomes accompanied by an elevation in mRNA expression of phagocytic markers Mertk and Cd68 and a surge in the expression of microglial outward K⁺ currents in the VH compared to DH, suggesting a distinct basal phenotypic state of microglia across the two hippocampal poles. Overall, we characterized the molecular, morphological, ultrastructural, and functional profile of microglia at the two poles, suggesting that modifications in hippocampal subregions related to different microglial statuses can contribute to dissect the phenotypical aspects of many diseases in which microglia are known to be involved.

Bayesian models to explain autistic traits in psychiatric population

Introduction

Studies on psychiatric patients have shown that the presence of autistic traits affects the effectiveness of the treatment, decreasing the likelihood of positive clinical outcomes.

Objectives

The aim of the present study is to investigate which are the areas of overlap between psychiatric symptoms and the traits of the autism spectrum using a bayesian approach.

Methods

A sample of 190 adult psychiatric patients, diagnosed with schizophrenia, bipolar disorder, major depression, and personality disorder participated in the study. The RAADS-R questionnaire was used to assess the presence of autistic traits. The severity of psychiatric symptoms was measured with the BPRS and PANSS scales, the perceived well-being and disability using the Whodas and Whoqol scales, the TOL and STROOP for the measurement of executive functions, the attentional matrices for visual-spatial attention, the Raven for general cognitive skills.

Results

No difference emerged between the diagnoses regarding the presence of symptoms of the autism spectrum, which affects 64% of subjects. Logistic regression showed that the severity of symptoms measured as BPRS and PANSS predicted the probability of having autistic traits. Bayesian regression showed that specific autistic traits are indicative of executive functions deficits. Namely, motor impairment severity measured at RAADS is strongly predicted by rule violation with number of correct moves measured at TOL. The other executive functions seemed to be only moderately linked to autistic traits.

Conclusions

These results provide new information about the expression of comorbidity with autism in psychiatric patients.

Altered subcortical emotional salience processing differentiates Parkinson's patients with and without psychotic symptoms

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Emotional salience processing differentiates PD patients with and without psychosis.

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Enhanced striatal, hippocampal and midbrain responses in PD patients with psychosis.

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Indication for ‘jumping to conclusions’ bias in the same PD patients with psychosis.

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Aberrant top-down and salience processing associated with PD psychosis.

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Similar deficits as proposed in ‘aberrant salience hypothesis’ of schizophrenia.

Objective

Current research does not provide a clear explanation for why some patients with Parkinson’s Disease (PD) develop psychotic symptoms. The ‘aberrant salience hypothesis’ of psychosis has been influential and proposes that dopaminergic dysregulation leads to inappropriate attribution of salience to irrelevant/non-informative stimuli, facilitating the formation of hallucinations and delusions. The aim of this study is to investigate whether non-motivational salience is altered in PD patients and possibly linked to the development of psychotic symptoms.

Methods

We investigated salience processing in 14 PD patients with psychotic symptoms, 23 PD patients without psychotic symptoms and 19 healthy controls. All patients were on dopaminergic medication for their PD. We examined emotional salience using a visual oddball fMRI paradigm that has been used to investigate early stages of schizophrenia spectrum psychosis, controlling for resting cerebral blood flow as assessed with arterial spin labelling fMRI.

Results

We found significant differences between patient groups in brain responses to emotional salience. PD patients with psychotic symptoms had enhanced brain responses in the striatum, dopaminergic midbrain, hippocampus and amygdala compared to patients without psychotic symptoms. PD patients with psychotic symptoms showed significant correlations between the levels of dopaminergic drugs they were taking and BOLD signalling, as well as psychotic symptom scores.

Conclusion

Our study suggests that enhanced signalling in the striatum, dopaminergic midbrain, the hippocampus and amygdala is associated with the development of psychotic symptoms in PD, in line with that proposed in the ‘aberrant salience hypothesis’ of psychosis in schizophrenia.

Preoperative Evaluation of Ferritinemia in Primary Epithelial Ovarian Cancer

Aims and background

High ferritin serum levels have been reported in patients suffering from various malignancies. The aim of this study was to evaluate the role of ferritinemia in the preoperative diagnosis of ovarian carcinoma.

Methods

Between March 1993 and September 1996, 60 patients suffering from ovarian carcinoma were surgically treated at our Department. Their ferritin serum levels were measured preoperatively by a solid-phase, two-site chemiluminescent immunometric assay and compared with those of a group of 60 healthy, age-matched, non pregnant controls.

Results

The mean serum concentration of ferritin was 54.7 ± 7.8 ng/ml (range, 14–135) in healthy controls and 112.3 ± 21.2 ng/ml (range, 9–947) in patients with ovarian carcinoma. The difference was statistically significant (P = 0.005, X2 test = 7.951). Serum ferritin was elevated preoperatively (cutoff ≥ 120 ng/ml) in 18/60 patients with malignancy (sensitivity 30%), whereas the CA 125 levels were above the cutoff in 53/60 patients (sensitivity 88.3%). Only 2/60 women of the control group had ferritin titers > 120 ng/ml (specificity 96.7%). The ferritin levels increased with advancing disease stage; no significant correlation was found between ferritin concentration and neoplastic histology and grading. The mean serum iron levels were also measured preoperatively in patients with ovarian carcinoma and healthy controls. They were 57.2 ± 3.8 and 66.3 ± 2.61 μg/dl, respectively, and the difference was not significant (P = 0.655, X2 test= 0.200).

Conclusions

The present study underlines that although ferritin shows an elevated specificity, its low sensitivity does not suggest any true usefulness as a tumor marker in epithelial ovarian cancer.

Massive Retro-Pneumoperitoneum and Lower Limb Subcutaneous Emphysema After Pediatric Heart Transplantation: A Case Report

An emphysema in a lower limb is usually a clinical sign of a severe and life-threatening infection. We report a rare case of subcutaneous emphysema of the left lower limb associated with a massive retro-pneumoperitoneum and pneumatosis intestinalis after cardiac transplantation in a 4-year-old girl. The child was nearly asymptomatic beside an abdominal distension. A benign pneumoperitoneum associated with an extensive pneumatosis intestinalis is a rare complication after organ transplantation and should be treated conservatively. The association with an emphysema in a lower limb in a child has not been previously reported to our knowledge in the literature.

An adolescent with persistent cervical lymphadenopathy and retropharyngeal abscess: case report

Tuberculosis keeps on representing a serious threat worldwide and one of the major challenge of our century. Different strategies have been developed in order to eradicate the disease, and particular attention is paid to children, who are at great risk for developing severe manifestations and poor outcome. Age at exposure, nutritional conditions and immune status can lead to great variability of disease expressions, with subsequent difficulties in making an appropriate and rapid diagnosis. Moreover, children coming from tuberculosis-endemic areas should be carefully evaluated for M. tuberculosis infection. Here we present a infrequent manifestation of extrapulmonary tuberculosis in a 13-years-old girl coming from Latin America: a superficial persistent cervical lymphadenopathy was associated with a totally asymptomatic retropharyngeal abscess. Diagnostic approach was discussed. Treatment consisted with a combination of surgical drainage of the abscess and a prolonged combined 6-month chemotherapy. The cervical lymphadenopathy disappeared and no relapses were found during the subsequent follow up.

The relationship between TORCH complex false positivity and obstetric outcome in patients with antiphospholipid syndrome

OBJECTIVE

The presence of TORCH IgM positivity is not a specific indicator of primary infection; the assessment of IgG avidity index has been shown to be useful in identifying or excluding primary infection in pregnant women with no pre-gestational TORCH serology. TORCH is an acronym for Toxoplasmosis, Others (HBV, syphilis, Varicella-Zoster virus, Epstein Barr virus, Coxsackie virus and Parvovirus), Rubella, Cytomegalovirus (CMV) and Herpes Simplex.

PATIENTS AND METHODS

Data from 54 pregnancies in women with antiphospholipid syndrome (APS) were assessed in comparison with data from 222 healthy pregnant women as controls. Each woman in both groups was systematically screened for TORCH IgG and IgM during pre-conceptional evaluation and/or at the beginning of pregnancy. The assessment of IgG avidity was also evaluated in order to identify primary infection or false positivity.

RESULTS

A significant increase of CMV IgM false positivity in APS in comparison with controls was detected. A worse pregnancy outcome was observed among APS patients having CMV IgM false positivity in comparison with APS patients without false positivity; in particular a statistically significant lower neonatal birth weight and a lower neonatal birth weight percentile were observed.

CONCLUSION

Our data suggest that the presence of CMV IgM false positivity could represent a novel prognostic factor for poor pregnancy outcome in APS patients.

PP029. Gestational hypertension and birth weight in twin pregnancies

INTRODUCTION

It is well known that hypertensive disorders of pregnancy are most frequent in twin pregnancies than in singleton ones. As demonstrated by a previous work of our group, twin pregnancies complicated by preeclampsia are associated with a higher rate of "small for gestational age" (SGA) neonates and inter-twin weight discordance than normotensive ones.

OBJECTIVES

The present study investigates the effect of gestational hypertension (GH) on neonatal birth weight, inter-twin weight discordance and growth restriction rate among twin pregnancies.

METHODS

A 26 year retrospective study was undertaken by examining 196 twin pregnancies complicated by GH, from January 1, 1980 to December 31, 2006, and comparing them to 912 normotensive twin pregnancies.

RESULTS

No significant differences were observed between the two groups in relationship to birth weight, inter-twin weight discordance and growth restriction rate, with a trend towards a higher birth weight in GH group. In normotensive group, the discordance >25% was associated with a lower gestational age at the delivery (p<0.00001). Moreover, the rate of pregnancies with SGA second twin gradually rose while paralleling the degree of discordance.

CONCLUSION

Contrary to preeclampsia in twin pregnancies the outcome of those complicated by GH is similar to normotensive ones. The trend towards a higher birth weight in GH seems apparently paradoxical, but it may reflect the role of uncomplicated hypertension in twin pregnancies: the increased blood pressure could be a physiologic response for more blood nutrient supply to the fetuses.

Forced chondrocyte expression of sonic hedgehog impairs joint formation affecting proliferation and apoptosis

Proliferation and apoptosis are two fundamental processes that occur during limb development, and in particular in joint formation. To study the role of hedgehog proteins in limbs, we have misexpressed Sonic Hedgehog specifically in chondrocytes. We found that the appendicular skeleton was severely misshapen while pelvic and shoulder girdles developed normally. In particular, we detected fusion of the elbow/knee joint, no definite carpal/tarsal, metacarpal/metatarsal bones and absence of distinct phalanges, fused in a continuous cartilaginous rod. Molecular markers of joints, such as Gdf5 and sFrp2 were absent at presumptive joint sites and Tenascin C, a molecule associated with joint formation and expressed in permanent cartilage, was expressed in a wider region in transgenic animals as compared to the wild type. The ratio of proliferating to non-proliferating chondrocytes was about two times higher in transgenic developing cartilage as compared to the wild type. Accordingly, the proapoptotic gene Bax was barely detectable in the growth plate of transgenic mice and Tunel assay showed the absence of apoptosis in presumptive joints at E15.5. Taken together, these results suggest that misexpression of Sonic Hedgehog causes apoptosis and proliferation defects leading to the lack of joint cavity and fusion of selected limb skeletal elements.

Celiac disease and inflammatory bowel disease in pregnancy

An adverse influence on reproductive life and obstetric complications are known to occur in women with celiac disease (clinical and subclinical disease) or inflammatory bowel diseases. Treatment can improve the pregnancy outcome; therefore, it is advisable that a clinical evaluation is performed by a joint team of obstetricians, internists and surgeons. The preconception clinical evaluation of the affected women is useful to focus on the different clinical aspects of the disease and to indicate specific therapeutic strategies. In this study a review of the literature regard to celiac disease and inflammatory bowel disease in pregnancy is presented.

Skeletal dysplasia and defective chondrocyte differentiation by targeted overexpression of fibroblast growth factor 9 in transgenic mice

Mutations in fibroblast growth factor receptor 3 (FGFR3) cause several human chondrodysplasias, including achondroplasia, the most common form of dwarfism in humans. From in vitro studies, the skeletal defects observed in these disorders have been attributed to constitutive activation of FGFR3. Here we show that FGF9 and FGFR3, a high-affinity receptor for this ligand, have similar developmental expression patterns, particularly in areas of active chondrogenesis. Targeted overexpression of FGF9 to cartilage of transgenic mice disturbs postnatal skeletal development and linear bone growth. The growth plate of these mice exhibits reduced proliferation and terminal differentiation of chondrocytes similar to that observed in the human disorders. The observations provide evidence that targeted, in vivo activation of endogenous FGFR3 inhibits bone growth and demonstrate that signals derived from FGF9-FGFR3 interactions can physiologically block endochondral ossification to produce a phenotype characteristic of the achondroplasia group of human chondrodysplasias.

Analgesic effects of nonsteroidal anti-inflammatory drugs in cancer pain due to somatic or visceral mechanisms

The role of nonsteroidal anti-inflammatory drugs (NSAIDs) is well established in the treatment of cancer pain. This class of drugs is considered particularly effective in pain due to somatic mechanisms, although proof of this observation is lacking. To ascertain whether NSAIDs are more effective in specific nociceptive forms of cancer pain, they were administered alone or added to opioids in 32 patients with a sole pain mechanism, somatic pain due to bone metastases (17 patients) or visceral pain (15 patients), respectively. Pain intensity, mean doses of opioids used, and symptoms were recorded after starting NSAID. A significant reduction in pain intensity was found at 3, 7, and 14 days. No differences in pain intensity between the two groups were observed. However, patients with a visceral mechanism required higher opioid doses after a week of treatment. No differences in adverse effects were reported. NSAIDs may be useful drugs in the management of cancer pain, regardless of the mechanism of pain involved. The incidence of adverse effects during prolonged administration should be assessed in future studies.

[Mucinous adenocarcinoma of the ovary in pregnancy]

A clinical case of ovarian adenocarcinoma during pregnancy is reported. The diagnostic and therapeutic problems which may be encountered, are illustrated. The data found in the literature concerning ovarian carcinoma in pregnancy are not so many. Most authors agree for the prosecution of pregnancy, with a careful observation of the patient. Also in this case, with a careful observation, an outcome without risk for the mother and the fetus has been obtained. After one month from birth, the surgical therapy has been completed. The tumoral markers CA 125 and CA 72-4 after birth were normal. After one year from intervention, the patient is good health.

Craniofacial and otic capsule abnormalities in a transgenic mouse strain with a Col2a1 mutation

Abnormal craniofacial features of a transgenic mouse model of chondrodysplasia with a type II collagen mutation (Gly574Ser) are described in this report. In addition to a shortened mandible and cleft palate, a misshapen otic capsule was observed. Interestingly, hearing impairment is often a component of the chondrodysplasia phenotype that results from mutations in COL2A1. To identify a potential mechanism in the hearing loss associated with type II collagen mutations, we examined the development of the otic capsule in the transgenic mice. It appeared to be smaller overall, relative to the skull proportions, and rather than the normal rounded dimensions, the transgenic capsule was flattened and elongated. We speculate that the cartilage of the developing otic capsule was less able to resist the mechanical forces from the developing brain and other tissues within the cranium and thus became deformed under pressure. We further speculate that the hearing loss associated with the chondrodysplasia phenotype is at least partially due to these defects in the developing cartilage matrix of the otic capsule.

Dextropropoxyphene versus morphine in opioid-naive cancer patients with pain

The role of opioids for moderate pain (so-called "weak" opioids) in the second step of the World Health Organization's analgesic ladder has been investigated in a prospective randomized study. Sixteen patients were administered dextropropoxyphene (DPP) in a dosage ranging from 120 mg to 240 mg daily (group 1), and 16 patients were administered the lowest doses (20 mg daily) of commercially available controlled-release morphine (group 2). Equianalgesic doses of oral morphine, pain relief, and symptoms during the first 10 days of therapy and during the last 4 weeks before death were assessed. Three of 16 patients maintained DPP until death, whereas three patients in group 2 were switched to DPP due to the occurrence of intolerable side effects. Intensity and frequency of nausea and vomiting, drowsiness, and dry mouth were higher in group 2 than in group 1 during the initial treatment. These results stress the role of "weak" opioids during the induction of opioid therapy in opioid-naive cancer patients.

Type II collagen pro-alpha-chains containing a Gly574Ser mutation are not incorporated into the cartilage matrix of transgenic mice

The biochemical consequences of a type II procollagen mutation that contained a Gly574Ser amino acid substitution were analyzed in a transgenic mouse strain. The mutation correlated with one previously characterized in a patient with the lethal human chondrodysplasia, hypochondrogenesis (Horton et al., 1992), and resulted in a similar shortlimbed phenotype. There were fewer collagen fibrils present in the transgenic cartilage and reduced immunofluorescence of cartilage matrix using a type II collagen antibody. Pepsin-extracted collagen from transgenic mouse embryo cartilage was analyzed electrophoretically and indicated less type II as well as type XI collagen compared to their wild-type littermates. A pulse-chase experiment was performed to evaluate the biosynthesis and fate of type II collagen. Chondrocytes isolated from transgenic tissue synthesized fewer stable molecules, resulting in decreased secretion of the procollagen chains. By amino acid sequence analysis of the type II collagen peptides from cartilage of transgenic mouse embryos, serine was not detected at residue 574, the site mutated in the transgene. Based on sequence data, we believe that the molecules incorporated into collagen fibrils of the extracellular matrix, while fewer in number, were composed of normal alpha 1(II) chains.

High prevalence of hepatitis C virus infection in patients with B-cell lymphoproliferative disorders in Italy

Starting from the observation that a number of consecutive patients with non-Hodgkin's lymphoma (NHL) resulted positive for hepatitis C virus (HCV) antibodies on routine testing, we set up a survey for HCV contact prevalence in all patients with lymphoproliferative disorders (LPD) followed in our institution. We searched for HCV antibodies by a third-generation ELISA technique, followed by a confirmation test (RIBA III); serum viral RNA and HCV genotype were investigated by a RT-PCR technique. We screened a total of 315 patients suffering from B-NHL (91), multiple myeloma (56), MGUS (48), chronic lymphocytic leukemia (57), Waldentrom's macroglobulinemia (13), Hodgkin's disease (HD)(43), and T-NHL (9). While only 1 of 52 patients with a non-B-LPD (HD or T-NHL) had signs of HCV contact (i.e., 1.9%, which is in the range of the normal population in the South of Italy), 59 of 263 patients with a B-LPD (22.4%) had HCV antibodies or RNA, or both, with no major differences among the various types of disorders, except for WM, in which the rate was higher (61.5%). The same prevalence was found for patients tested at diagnosis or during the follow-up, and in transfused or never-transfused patients. Only a few patients were aware of having a liver disease; one-half of HCV-positive patients never had transaminase increase. A review of data from Central and Northern Italy is included, showing similar findings; a report from Japan has confirmed such an association, while limited surveys in England have not revealed any correlation. These findings may have important biological and clinical implications.

High prevalence of hepatitis C virus infection in patients with B-cell lymphoproliferative disorders in Italy

Starting from the observation that a number of consecutive patients with non-Hodgkin's lymphoma (NHL) resulted positive for hepatitis C virus (HCV) antibodies on routine testing, we set up a survey for HCV contact prevalence in all patients with lymphoproliferative disorders (LPD) followed in our institution. We searched for HCV antibodies by a third-generation ELISA technique, followed by a confirmation test (RIBA III); serum viral RNA and HCV genotype were investigated by a RT-PCR technique. We screened a total of 315 patients suffering from B-NHL (91), multiple myeloma (56), MGUS (48), chronic lymphocytic leukemia (57), Waldentrom's macroglobulinemia (13), Hodgkin's disease (HD)(43), and T-NHL (9). While only 1 of 52 patients with a non-B-LPD (HD or T-NHL) had signs of HCV contact (i.e., 1.9%, which is in the range of the normal population in the South of Italy), 59 of 263 patients with a B-LPD (22.4%) had HCV antibodies or RNA, or both, with no major differences among the various types of disorders, except for WM, in which the rate was higher (61.5%). The same prevalence was found for patients tested at diagnosis or during the follow-up, and in transfused or never-transfused patients. Only a few patients were aware of having a liver disease; one-half of HCV-positive patients never had transaminase increase. A review of data from Central and Northern Italy is included, showing similar findings; a report from Japan has confirmed such an association, while limited surveys in England have not revealed any correlation. These findings may have important biological and clinical implications.

Activation of Stat1 by mutant fibroblast growth-factor receptor in thanatophoric dysplasia type II dwarfism

The achondroplasia class of chondrodysplasias comprises the most common genetic forms of dwarfism in humans and includes achondroplasia, hypochondroplasia and thanatophoric dysplasia types I and II (TDI and TDII), which are caused by different mutations in a fibroblast growth-factor receptor FGFR3 (ref. 1). The molecular mechanism and the mediators of these FGFR3-related growth abnormalities are not known. Here we show that mutant TDII FGFR3 has a constitutive tyrosine kinase activity which can specifically activate the transcription factor Stat1 (for signal transducer and activator of transcription). Furthermore, expression of TDII FGFR3 induced nuclear translocation of Stat1, expression of the cell-cycle inhibitor p21(WAF1/CIP1), and growth arrest of the cell. Thus, TDII FGFR3 may use Stat1 as a mediator of growth retardation in bone development. Consistent with this, Stat1 activation and increased p21(WAF1/CIP1) expression was found in the cartilage cells from the TDII fetus, but not in those from the normal fetus. Thus, abnormal STAT activation and p21(WAF1/CIP1) expression by the TDII mutant receptor may be responsible for this FGFR3-related bone disease.

Skeletal development in transgenic mice expressing a mutation at Gly574Ser of type II collagen

Skeletal development of transgenic mice with a type II collagen mutation was analyzed and compared with wild-type littermates. The single base substitution in Col2a1 resulted in a glycine to serine mutation within the helical domain and corresponded to one previously identified in a patient with the lethal human chondrodysplasia, hypochondrogenesis (Horton et al. [1992] Proc. Natl. Acad. Sci. U.S.A. 89:4583-4587). Skeletal staining of embryos from 14.5 through 18.5 days of gestation demonstrated a dwarf phenotype in the transgenic embryos, most notably short limb bones and vertebral column that was first detected at 15.5 days post-coitus. In addition to the reduced length, the extent of ossification was less in the transgenic mice. The architecture of the long bone growth plate was abnormal in the transgenic tissue, in particular there was no discernible proliferative zone. There were few stacks of characteristically flattened cells and the overall length of the growth plate in the mutant embryos was reduced. At the ultrastructural level, there were fewer collagen fibrils present in the transgenic mouse cartilage compared to that of wild-type littermates. Ultrastructural localization of collagen types II, IX and XI revealed a similar pattern between the transgenic and wild-type pups, suggesting that the collagen fibrils present in the matrix of littermates with both phenotypes had a similar composition. Skeletal analysis and cartilage histochemistry indicated that effect of the type II collagen mutation was to reduce the density of the collagen fibrils within the cartilage matrix which was associated with delayed bone formation and resulted in a short-limbed phenotype.

Nocturnal enuresis and daytime wetting: a multicentric trial with oxybutynin and desmopressin

OBJECTIVE

Different etiopathological mechanisms of enuresis are today under study, and different therapies and drugs have been proposed. The Italian Multicentric Trial was undertaken in twelve pediatric and urological centers in order to assess the efficacy of two of the most popular drugs, desmopressin (DDAVP) and oxybutynin.

METHODS

114 enuretic patients were enrolled in the study. After a 2-week observation period, 66 patients with primary monosymptomatic enuresis were treated with DDAVP, 30 micrograms/day intranasally, for 6 weeks, 48 patients with enuresis and voiding dysfunction were randomly assigned to a protocol with oxybutynin alone or oxybutynin plus DDAVP. The efficacy of the two drugs was measured in terms of reduction of wet nights per week during the 6-week treatment period and a 2-week follow-up period. Children with 0-3 dry nights/week were considered as nonresponders.

RESULTS

Patients with monosymptomatic enuresis treated with DDAVP reported a significantly lower number of wet night during treatment than during the baseline period, with 79% showing a 'good' (6-7 dry nights/week) or 'intermediate' response (4-5 dry nights/week). Of the patients with diurnal voiding disturbances and enuresis, those treated with oxybutynin alone had a 54% success rate. The patients treated with both oxybutynin and DDAVP showed a better response, with a 71% rate of success.

CONCLUSIONS

The efficacy of the two drugs is confirmed in patients carefully selected on the clinical basis of voiding disturbances. In patients with enuresis and voiding dysfunction, the reduced urinary output and the lower bladder filling rate due to DDAVP can reduce uninhibited bladder contractions, thus enhancing the oxybutynin action.

A 182 bp fragment of the mouse pro alpha 1(II) collagen gene is sufficient to direct chondrocyte expression in transgenic mice

Type II collagen is a major chondrocyte-specific component of the cartilage extracellular matrix and it represents a typical differentiation marker of mature chondrocytes. In order to delineate cis-acting elements of the mouse pro alpha 1(II) collagen gene that control chondrocyte-specific expression in intact mouse embryos, we generated transgenic mice harboring chimeric constructions in which varying lengths of the promoter and intron 1 sequences were linked to a beta-galactosidase reporter gene. A construction containing a 3,000 bp promoter and a 3,020 bp intron 1 fragment directed high levels of beta-galactosidase expression specifically to chondrocytes. Expression of the transgene coincided with the temporal expression of the endogenous gene at all stages of embryonic development. Successive deletions of intron 1 delineated a 182 bp fragment which targeted beta-galactosidase expression to chondrocytes with the same specificity as the larger intron 1 fragment. Transgenic mice harboring a 309 bp Col2a1 promoter lacking intron 1 tester sequences showed no beta-galactosidase expression in chondrocytes. Reduction of the 182 bp fragment to a 73 bp subfragment surrounding a decamer sequence previously reported to be involved in chondrocyte specificity, resulted in loss of transgene expression in chondrocytes. When the Col2a1 promoter was replaced with a minimal beta-globin promoter, the 182 bp intron 1 sequence was still able to target expression of the transgene to chondrocytes. We conclude that a 182 bp intron 1 DNA segment of the mouse Col2a1 gene contains the necessary information to confer high-level, temporally correct, chondrocyte expression on a reporter gene in intact mouse embryos and that Col2a1 promoter sequences are dispensable for chondrocyte expression.

Use of a new rat chondrosarcoma cell line to delineate a 119-base pair chondrocyte-specific enhancer element and to define active promoter segments in the mouse pro-alpha 1(II) collagen gene

We show that a new rat chondrosarcoma (RCS) cell line established in long-term culture from the Swarm tumor displayed a stable differentiated chondrocyte-like phenotype. Indeed, these cells produced the collagen types II, IX, and XI and alcian blue-stainable cartilage-specific proteoglycans, but no type I or type III collagen. To functionally characterize their chondrocytic nature, the cells were stably transfected with a type II collagen/beta geo chimeric gene which confers essentially perfect chondrocyte-specific expression in transgenic mice. RCS cells expressed both beta-galactosidase and G418 resistance, in comparison with similarly transfected 10T1/2 and NIH/3T3 fibroblasts which did not. These cells were then used to perform a systematic deletion analysis of the first intron of the mouse type II collagen gene (Col2a1) using transient expression experiments to determine which segments stimulated expression of a luciferase reporter gene in RCS cells but not in 10T1/2 fibroblasts. Cloning of two tandem copies of a 156-base pair (bp) intron 1 fragment (+2188 to +2343) in a construction containing a 314-bp Col2a1 promoter caused an almost 200-fold increase in promoter activity in RCS cells but no increase in 10T1/2 cells. DNase I footprint analysis over this 156-bp fragment revealed two adjacent protected regions, FP1 and FP2, located in the 3'-half of this segment, but no differences were seen with nuclear extracts of RCS cells and 10T1/2 fibroblasts. Deletion of FP2 to leave a 119-bp segment decreased enhancer activity by severalfold, but RCS cell specificity was maintained. Further deletions indicated that sequences both in the 5' part of the 119-bp fragment and in FP1 were needed simultaneously for RCS cell-specific enhancer activity. A series of deletions in the promoter region of the mouse Col2a1 gene progressively reduced activity when these promoters were tested by themselves in transient expression experiments. However, these promoter deletions were all activated to a similar level in RCS cells by a 231-bp intron 1 fragment that included the 156-bp enhancer. The RCS cell-specific activity persisted even if the Col2a1 promoter was replaced by a minimal adenovirus major late promoter. This 231-bp intron 1 fragment also had strong enhancing activity in transiently transfected mouse primary chondrocytes. Our experiments establish the usefulness of RCS cells as an experimental system for studies of the control of chondrocyte-specific genes, provide an extensive delineation of segments in the Col2a1 first intron involved in chondrocyte-specific activity, and show that promoter sequences are dispensable for chondrocyte specificity.

Developmental expression of a type II collagen/beta-galactosidase fusion gene in transgenic mice

The correct temporal and spatial expression of the type II collagen gene is believed to be important for normal development and growth of the skeleton and the eye, i.e., tissues where the protein product is predominantly found. To study transcriptional activation of type II collagen gene in skeletal and nonskeletal tissues we produced transgenic mice carrying murine proalpha1(II) collagen/beta-galactosidase fusion gene constructs. The expression of the fusion gene was found to depend on the presence of intron 1 deleted failed to reveal any beta-galactosidase activity confirming the important role of regulatory sequences within intron 1 of the gene. High-level expression of the functional construct was clearly confined to cartilaginous tissues but transient low-level expression was also observed in extraskeletal locations, such as the developing brain and the notochord. The results demonstrate that the regulatory elements in the proalpha1(II) collagen/beta-galactosidase fusion gene construct confer both temporal and spatial specificity indistinguishable from that of the endogenous proalpha1(II) collagen gene as determined by the presence of the corresponding mRNA by in situ hybridization. Furthermore the beta-galactosidase activity correlated well with the progression of chondrogenesis as seen by staining of whole mouse embryos with Alizarin red S and Alcian blue in the hybrid mouse strain used for microinjections. The transgenic mouse line produced should prove useful for studies on various aspects of chondrogenesis. Furthermore, the data shows that the regulatory elements present in the construct are sufficient for targetting the expression of other genes in cartilage.

Transgenic mice with deficiencies in cartilage collagens: possible models for gene therapy

We address three issues that are important when considering somatic gene therapy approaches to osteoarthritis (OA) and related syndromes. First, only those diseases for which a precise molecular etiology has been established should be contemplated for somatic gene therapy. Second, DNA sequences should be identified that restrict expression of correcting genes to chondrocytes; we discuss the use of transgenic mice to identify such sequences. Third, we emphasize the usefulness of establishing animal models that mimic human OA syndromes by genetic manipulations. These transgenic models should be essential for testing gene therapy approaches in vivo.

Type X collagen gene expression in mouse chondrocytes immortalized by a temperature-sensitive simian virus 40 large tumor antigen

Mouse endochondral chondrocytes were immortalized with a temperature-sensitive simian virus 40 large tumor antigen. Several clonal isolates as well as pools of immortalized cells were characterized. In monolayer cultures at the temperature permissive for the activity of the large tumor antigen (32 degrees C), the cells grew continuously with a doubling time of approximately 2 d, whereas they stopped growing at nonpermissive temperatures (37 degrees C-39 degrees C). The cells from all pools and from most clones expressed the genes for several markers of hypertrophic chondrocytes, such as type X collagen, matrix Gla protein, and osteopontin, but had lost expression of type II collagen mRNA and failed to be stained by alcian blue which detects cartilage-specific proteoglycans. The cells also contained mRNAs for type I collagen and bone Gla protein, consistent with acquisition of osteoblastic-like properties. Higher levels of mRNAs for type X collagen, bone Gla protein, and osteopontin were found at nonpermissive temperatures, suggesting that the expression of these genes was upregulated upon growth arrest, as is the case in vivo during chondrocyte hypertrophy. Cells also retained their ability to respond to retinoic acid, as indicated by retinoic acid dose-dependent and time-dependent increases in type X collagen mRNA levels. These cell lines, the first to express characteristic features of hypertrophic chondrocytes, should be very useful to study the regulation of the type X collagen gene and other genes activated during the last stages of chondrocyte differentiation.

Normal long bone growth and development in type X collagen-null mice

To investigate the role of type X collagen in skeletal development, we have generated type X collagen-null mice. Surprisingly, mice without type X collagen were viable and fertile and had no gross abnormalities in long bone growth or development. No differences were detected between the type X collagen-null mice and controls when growth plates of both newborn and 3-week old mice were examined by histology and by immunostaining for extracellular matrix components of bone including osteopontin, osteocalcin and type II collagen. Our results suggest that type X collagen is not required for long bone development. However, mice and humans with dominant acting type X collagen mutations have bone abnormalities, suggesting that only the presence of abnormal type X collagen can modify bone growth and development.

Characterization of primary cultures of chondrocytes from type II collagen/beta-galactosidase transgenic mice

Studies on the function of extracellular matrix components of cartilages and on chondrocyte-specific regulatory mechanisms will benefit from approaches in which transgenic mice and cell cultures will complement each other. We therefore established and extensively characterized primary cultures of mouse chondrocytes isolated from rib growth plates of newborn mice harboring a transgene in which type II collagen gene regulatory sequences were driving expression of an E. coli beta-galactosidase reporter gene. Primary chondrocytes expressed a fully differentiated phenotype in monolayer culture, producing mRNAs for the collagen types II, IX and X, and for the transgene. Transgenic cells also synthesized high levels of E. coli beta-galactosidase, easily quantifiable and also detectable in individual cells by X-gal staining. When chondrocytes were isolated from transgenic mice in which beta-galactosidase was fused to the product of the neomycin resistance gene, they displayed resistance to G418. After one to two weeks in culture, chondrocytes progressively lost expression of the transgenes, in parallel with that of cartilage-specific genes, and started expressing high levels of type I collagen RNA. The use of transgenic chondrocytes allowed us to easily score phenotypic changes by assaying beta-galactosidase activity and neomycin resistance. Cultures of mouse chondrocytes, such as those reported here, should also help characterize biochemically the phenotypes of other transgenic mice in studies of genetic diseases of cartilages and of mechanisms involved in chondrogenesis.

Abnormal craniofacial morphology and cartilage structure in transgenic mice harboring a Gly --> Cys mutation in the cartilage-specific type II collagen gene

Gross morphology and histology of the craniofacial complex was studied in the offspring of two transgenic founder mice, Gly85-1 and Gly85-3, carrying several copies of a mouse type II collagen transgene that causes a single amino acid substitution (Gly-->Cys) at position 85 of the triple helix. The newborn transgenic mice had a short snout and mandible, a protruding tongue, a cleft of the secondary palate with the tongue situated between the shelves, and a doming cranial vault. Radiological examination revealed that the cranial base of the transgenic mice was shorter and its posterior part downward bent; in addition both the palate and the cribriform plate were less extended in relation to the cranial base than in the controls. Histologically the midline cartilaginous structures were composed of densely packed enlarged chondrocytes in a reduced extracellular matrix containing abnormally thick collagen fibrils. With the exception of the zone of hypertrophic chondrocytes the matrix also showed a loss of glycosaminoglycans. The cellular architecture of the basicranial synchondroses was disorganized, and the nasocerebrally oriented collagen fibrils formed unevenly distributed aggregates. The craniofacial morphology described here for the Gly85 mice shares features typical for other mouse mutations causing short limbed dwarfism. The observations indicate that defective cartilage production causes disproportionate craniofacial growth. Transgenic mice with specific mutations in cartilage-specific genes should therefore be useful for elucidating the complex mechanisms involved in determining the craniofacial growth.

Assembly of cartilage collagen fibrils is disrupted by overexpression of normal type II collagen in transgenic mice

Cartilage collagen fibrils, which are characterized by their thin, uniform diameters, are formed of a multicomponent system of three collagen types (II, IX, and XI) and interacting proteoglycans. We have used a genetic approach to test whether the proper assembly of this multiprotein structure was altered by overexpression of one of its normal components. Here we show that in transgenic mice in which the normal mouse alpha 1(II) collagen is overexpressed, thick abnormal collagen fibrils are generated. Mice that showed the highest expression of the transgene also displayed a larger proportion of abnormal fibrils and died at birth. We propose that an imbalance among the constituents of the cartilage collagen fibrils disrupts the mechanism that controls their assembly. The results show the applicability of the transgenic mice system to studies of complex multicomponent protein assemblies in intact animals.

The mouse collagen X gene: complete nucleotide sequence, exon structure and expression pattern

Overlapping genomic clones covering the 7.2 kb mouse alpha 1(X) collagen gene, 0.86 kb of promoter and 1.25 kb of 3'-flanking sequences were isolated from two genomic libraries and characterized by nucleotide sequencing. Typical features of the gene include a unique three-exon structure, similar to that in the chick gene, with the entire triple-helical domain of 463 amino acids coded by a single large exon. The highest degree of amino acid and nucleotide sequence conservation was seen in the coding region for the collagenous and C-terminal non-collagenous domains between the mouse and known chick, bovine and human collagen type X sequences. More divergence between the sequences occurred in the N-terminal non-collagenous domain. Similarity between the mammalian collagen X sequences extended into the 3'-untranslated sequence, particularly near the polyadenylation site. The promoter of the mouse collagen X gene was found to contain two TATAA boxes 159 bp apart; primer extension analyses of the transcription start site revealed that both were functional. The promoter has an unusual structure with a very low G + C content of 28% between positions -220 and -1 of the upstream transcription start site. Northern and in situ hybridization analyses confirmed that the expression of the alpha 1(X) collagen gene is restricted to hypertrophic chondrocytes in tissues undergoing endochondral calcification. The detailed sequence information of the gene is useful for studies on the promoter activity of the gene and for generation of transgenic mice.

Chondrodysplasia in transgenic mice harboring a 15-amino acid deletion in the triple helical domain of pro alpha 1(II) collagen chain

We have generated transgenic mice by microinjection of a 39-kb mouse pro alpha 1(II) collagen gene construct containing a deletion of exon 7 and intron 7. This mutation was expected to disturb the assembly and processing of the homotrimeric type II collagen molecule in cartilage. Expression of transgene mRNA at levels equivalent or higher than the endogenous mRNA in the offspring of two founder animals resulted in a severe chondrodysplastic phenotype with short limbs, hypoplastic thorax, abnormal craniofacial development, and other skeletal deformities. The affected pups died at birth due to respiratory distress. Light microscopy of epiphyseal growth plates of transgenic pups demonstrated a marked reduction in cartilaginous extracellular matrix and disruption of the normal organization of the growth plate. The zone of proliferating chondrocytes was greatly reduced whereas the zone of hypertrophic chondrocytes was markedly increased extending deep into the diaphysis suggestive of a defect in endochondral ossification. Electron microscopic examination revealed chondrocytes with extended RER, a very severe reduction in the amount of cartilage collagen fibrils, and abnormalities in their structure. We postulate that the deletion in the alpha 1(II) collagen acts as a dominant negative mutation disrupting the assembly and secretion of type II collagen molecules. The consequences of the mutation include interference with normal endochondral ossification. These mice constitute a valuable model to study the mechanisms underlying human chondrodysplasias and normal bone formation.

Specific hybridization probes for mouse alpha 2(IX) and alpha 1(X) collagen mRNAs

We have used polymerase chain reaction (PCR) technology and available cross-species sequence information to construct cDNA probes for mouse alpha 2(IX) and alpha 1(X) collagen transcripts. Sequencing confirmed the identification of the clones. Northern analysis proved sufficient divergence of the cloned sequences from other collagen transcripts: specific detection of the mouse 2.9 kb alpha 2(IX) and 3.3 kb alpha 1(X) collagen mRNAs was seen under normal hybridization and washing conditions.