Computed tomography follow-up of acute portal vein thrombosis.

PURPOSE: To assess the evolution of acute portal vein thrombosis by computed tomography (CT). PATIENTS AND METHODS: Retrospective single-centre study (2005-2011) including 23 patients who had an initial CT scan and a CT scan during the first year. The analysis compared the last CT scan available with that of the initial CT scan. Neoplastic thrombosis, extrinsic compressions and cavernomas were excluded. All patients received anticoagulant treatment. RESULTS: The causes included: cirrhoses (n = 6), blood disorders (n = 4), locoregional inflammations and infections (n = 8), abdominal surgery (n = 1). The thrombosis was idiopathic in 4 cases. After a mean follow-up of 7.7 months, 7 patients (30%) benefited from a restitutio ad integrum of the portal system, a stable or partially regressive thrombosis was noted in 12 patients (52%) and an aggravation of the thrombosis was noted in 4 patients (18%). In the sub-group of portal vein thrombosis, repermeabilisation was noted in 37.5% of the patients (6/16) and 6 cavernomas developed. CONCLUSION: CT monitoring helps follow the evolution of an acute portal vein thrombosis and demonstrates complete repermeabilisation of the portal vein in 30% of the patients.

[Splenic cyst during pregnancy: a rare disease with difficult management]. / Kyste splénique et grossesse : une pathologie rare de prise en charge difficile.

Maternal splenic cyst during pregnancy seems to be a rare disease whose treatment is not codified. The most feared complication of these cysts is the rupture. In case of rupture, 60% of cases occur during the third trimester of pregnancy and result in a significant maternal and fetal morbidity and mortality. We examine the two main modes of treatment used nowadays: surgical splenectomy or radiological drainage.

Reporter gene expression from LTR-circles as tool to identify HIV-1 integrase inhibitors.

Early HIV-1 integrase inhibitors, such as compounds containing a ß-diketo acid moiety, were identified by extensive high-throughput screening campaigns. Traditionally, in vitro biochemical assays, measuring the catalytic activities of integrase, have been used for this purpose. However, these assays are confounded by the absence of cellular processes or cofactors that play a role in the integration of HIV-1 DNA in the cellular genome. In contrast to regular cell-based virus inhibition assays, which targets all steps of the viral replication cycle, a novel cellular screening assays was developed to enable the specific identification of integrase inhibitors, employing a readout that is linked with the inhibition of integrase activity. Therefore, a HIV-1 lentiviral vector equipped with the enhanced green fluorescent protein (eGFP) reporter gene was used to detect expression from extrachromosomal viral DNA (1- or 2-long terminal repeat circles), formed when integration of vector DNA into the cellular genome is prevented by an integrase inhibitor. In this assay, eGFP expression from the low residual level of transcriptional activity of extrachromosomal DNA was measured via high-throughput flow cytometry. An algorithm for analysis of eGFP expression histograms enabled the specific identification of integrase inhibitors. This assay is amenable for high throughput screening to identify inhibitors of HIV-1 integrase.

Local colorectal cancer recurrence: pelvic MRI evaluation.

Surveillance of colorectal cancer is currently based on dosage of tumoral markers, colonoscopy and multidetector row computed tomography. However, pelvic magnetic resonance imaging (MRI) and PET-CT are two second-line useful imaging modalities to assess colorectal cancer local recurrence (LR). The anatomical information derived from MRI combined to the functional information provided by diffusion-weighted imaging currently remain of value. Pelvic MRI is accurate not only for detection of pelvic colorectal recurrence but also for the prediction of absence of tumoral invasion in pelvic structures, and it may thus provide a preoperative road map of the recurrence to allow for appropriate surgical planning. As always, correlation of imaging and clinical findings in the multidisciplinary forum is paramount. MRI can also be used to follow-up LR treated with radiofrequency ablation. The aim of this review is to discuss clinical practice and application of MRI in the assessment or pelvic recurrence from colorectal cancer.

Cirrhotic and malignant ascites: differential CT diagnosis.

OBJECTIVES: To assess the diagnostic accuracy of the different computed tomography (CT) signs for differentiating between malignant and cirrhotic ascites. MATERIALS AND METHODS: We performed a retrospective study of 102 CT scans in adults, distributed into two groups based on the cirrhotic or malignant etiology of their ascites. The CT signs studied were ascites volume and relative distribution between the greater peritoneal cavity (GPC) and the omental bursa (OB), the density of the ascites, the thickness of the gallbladder wall, the thickness of the parietal peritoneum and its degree of enhancement, and tethered-bowel sign. RESULTS: The CT signs associated with malignant ascites were: presence of fluid in the omental bursa (P=0.003), thickening of the peritoneum its degree of enhancement (P=0.005), increased density of the ascites (P=0.01), and loss of mobility of bowel loops in the ascites (P=0.001). There was no difference in gallbladder wall thickness between the two groups. CONCLUSION: The CT scan can play a role in diagnosing malignant ascites. We confirm the usefulness of the indirect signs composed of distribution of ascites fluid, thickening and enhancement of the parietal peritoneum, and loss of mobility of the bowel loops in the ascites.

A novel high-throughput cellular screening assay for the discovery of HIV-1 integrase inhibitors.

The discovery of HIV-1 integrase inhibitors has been enabled by high-throughput screening and rational design of novel chemotypes. Traditionally, biochemical assays focusing on the strand transfer activity of integrase have been used to screen compound libraries for identification of novel inhibitors. In contrast, cellular screening assays enable a phenotypic or multi-target approach, and may result in identification of compounds inhibiting integrase in its natural context, the pre-integration complex. Furthermore, a cellular assay encompassing 3' processing, strand transfer and nuclear import may lead to the identification of compounds with novel mechanisms of action targeting cellular and viral factors. Therefore, a cellular screening assay was developed, which focused on integrase activity, where infection of MT4 cells with an HIV-1 based lentiviral vector was synchronized by temporary arrest at the reverse transcriptase step and subsequent release to enable integration. The assay was validated using a panel of antivirals and proved to be a robust cellular screening assay for the identification of novel integrase inhibitors.

CT in predicting abdominal cocoon in patients on peritoneal dialysis.

AIM: To evaluate the computed tomography (CT) signs of encapsulating peritoneal sclerosis (EPS) in patients on peritoneal dialysis (PD) as predictive factors for the evolution to abdominal cocoon (AC). MATERIALS AND METHODS: Clinical features and CT signs of 90 patients on PD were retrospectively reviewed. According to the clinical features, they were divided into three groups (asymptomatic, moderate, or severe). Clinical results were correlated with previously reported CT signs of EPS, i.e., peritoneal thickening, peritoneal calcifications, loculated fluids, small bowel faeces sign, small bowel obstruction, clustered bowel loops, pseudo sac, signs of bowel ischaemia or necrosis. AC was defined at CT by the association of clustered bowel loops and a pseudo sac. Statistical analysis was performed using the Fisher's exact test and the t-test. RESULTS: Although demonstrated in symptomatic patients (p=0.041), the occurrence of AC was not correlated with the severity of the symptoms (p=0.16). Among the CT signs, the presence of loculated fluids (p=0.011), a small bowel faeces sign (p=0.002); and small bowel obstruction (p=0.0001) were found to be statistically correlated with the appearance of an AC. Moreover, the association of loculated fluids, small bowel faeces sign, small bowel obstruction was extremely sensitive and specific in the development of AC (sensitivity=67%, specifity=100%, positive predictive value=100%, negative predictive value=96%). CONCLUSION: CT should be carried out in every symptomatic patient on PD. Indeed, the association of loculated fluid, small bowel faeces sign, and small bowel obstruction enables the prediction of the development of AC, which is likely to curtail PD and require surgery.

Pathogenic interactions between Chlamydophila psittaci and avian pneumovirus infections in turkeys.

Both Chlamydophila psittaci and avian pneumovirus (APV) are highly prevalent in Belgian turkeys and might contribute to the respiratory disease complex observed in turkeys. Initial outbreaks of chlamydiosis occur mostly at the age of 4-8 weeks, often accompanied by an APV infection in APV non-vaccinated farms. Regardless APV vaccination, breakthroughs of APV infection from 8 weeks on do occur, a period when also a second C. psittaci infection appears. Therefore, this study examined the pathogenicity of an APV superinfection in C. psittaci predisposed turkeys. Turkeys were infected with C. psittaci, APV or with C. psittaci followed by APV. Simulating the impact of an APV infection during the acute phase or latent phase of a C. psittaci infection, turkeys have been infected with APV at 1 and 5 weeks post C. psittaci infection, respectively. APV infection during the acute phase of a C. psittaci infection aggravates the severity of clinical signs, macroscopic lesions, pharyngeal APV excretion and histological tracheae lesions. In contrast, no clear interaction could be established after APV infection in latently C. psittaci infected specific pathogen-free (SPF) turkeys. This study clearly demonstrates the exacerbating role of APV during acute C. psittaci infection, which can play an important role in the respiratory disease complex of turkeys.

Protection of turkeys against Chlamydophila psittaci challenge by DNA and rMOMP vaccination and evaluation of the immunomodulating effect of 1 alpha,25-dihydroxyvitamin D(3).

Plasmid DNA expressing the major outer membrane protein (MOMP) of an avian Chlamydophila psittaci serovar D strain and recombinant MOMP (rMOMP) with or without the immunomodulating adjuvant 1 alpha,25-dihydroxyvitamin D(3) have been tested for their ability to elicit an immune response and induce protection in turkeys against challenge with the same serovar. Three vaccination strategies were compared: priming and boosting with either pcDNA1::MOMP or rMOMP and priming with pcDNA1::MOMP followed by rMOMP boosting. Turkeys primed with pcDNA1::MOMP showed significant protection against Cp. psittaci challenge, turkeys primed with rMOMP did not. The steroid hormone 1 alpha,25-dihydroxyvitamin D(3) augmented serum and mucosal antibody titres. However, higher antibody titres were not related to better protection and even had a negative effect on especially bacterial excretion.

Key role of Chlamydophila psittaci on Belgian turkey farms in association with other respiratory pathogens.

Two hundred turkey sera from eight Belgian and two French farms were tested for the presence of antibodies against avian pneumovirus (APV), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum, Mycoplasma meleagridis and Chlamydophila psittaci. At slaughter, C. psittaci, APV and ORT antibodies were detected in 94, 34 and 6.5% of the turkeys, respectively. No antibodies against M. gallisepticum or M. meleagridis were present. Additionally, turkeys on three Belgian farms were examined from production onset until slaughter using both serology and antigen or gene detection. All farms experienced two C. psittaci infection waves, at 3-6 and 8-12 weeks of age. Each first infection wave was closely followed by an ORT infection starting at the age of 6-8 weeks, which was still detectable when the second C. psittaci infection waves started. Animals on farm A were not vaccinated against APV leading to an APV subtype B outbreak accompanying the first C. psittaci infection wave. Despite subtype A APV vaccination on farms B and C, the second C. psittaci infection waves were accompanied (farm B) or followed (farm C) by a subtype B APV infection. On all farms respiratory signs always appeared together with a proven C. psittaci, APV and/or ORT infection. This study suggests an association between C. psittaci, APV and ORT, and indicates the multi-factorial aetiology of respiratory infections in commercial turkeys. All three pathogens should be considered when developing prevention strategies for respiratory disease.

Influence of maternal antibodies on Chlamydophila psittaci-specific immune responses in turkeys elicited by naked DNA.

Plasmid DNA (pcDNA1::MOMP D) expressing the major outer membrane protein (MOMP) of an avian Chlamydophila psittaci serovar D strain was tested for its ability to induce protective immunity against C. psittaci challenge in the presence of maternal antibodies. A combined parenteral (intramuscular injection) and mucosal route (DNA drops administered to the nares) of DNA inoculation was used. Following pcDNA1::MOMP vaccination, both T helper and B cell memory were primed. However, high maternal antibodies titres affected the induction of vaccine-specific antibody responses as assessed by MOMP-specific antibody levels in enzyme-linked immunosorbent assay (ELISA). Cell-mediated immunity was unaltered as demonstrated by the significantly heightened proliferative responses of peripheral blood lymphocytes (PBL) following vaccination. DNA vaccination could significantly reduce clinical symptoms, pharyngeal and cloacal excretion as well as Chlamydophila replication, even in the presence of maternal antibodies.

Missing links in the divergence of Chlamydophila abortus from Chlamydophila psittaci.

Pathological and serological evidence and DNA-DNA reassociation data indicate that Chlamydophila psittaci and Chlamydophila abortus are separate species. C. psittaci causes avian systemic disease and C. abortus causes abortion. Both previously belonged to Chlamydia psittaci are associated with zoonotic and enzootic outbreaks. Genetic studies suggest that they are closely related and because of the recent availability of diverse C. psittaci strains and comparative data for several genes, it was possible to explore this relationship. The parrot C. psittaci strain 84/2334 was found to have DNA sequences that were identical to an extrachromosomal plasmid in duck C. psittaci strain N352, to rnpB in strain R54 from a brown skua and to the rrn intergenic spacer in parakeet strain Prk/Daruma (from Germany, Antarctica and Japan, respectively). Analysis of ompA and the rrn spacer revealed progressive diversification of the strains, with 84/2334 resembling what might have been a recent ancestor of C. abortus. Another C. psittaci strain (VS225) showed evidence of having undergone convergent evolution towards the C. abortus-like genotype, whereas strain R54 diverged independently. For the first time, these studies link C. abortus in an evolutionary context to the C. psittaci lineage. It has been concluded that C. abortus diverged from C. psittaci, and so strain R54 was designated a C. psittaci strain. It is recommended that characterization of C. psittaci and C. abortus strains should utilize more than a single method and more than a single gene.

Chlamydophila psittaci DNA vaccination in turkeys in the presence of maternal antibodies.

Plasmid DNA (pcDNA1::MOMP D) expressing the major outer membrane protein of an avian Chlamydophila psittaci serovar D strain was tested for its ability to induce protective immunity against Chlamydophila psittaci challenge in the presence of maternal antibodies. A combined parenteral (intramuscular injection) and mucosal route (DNA drops administered to the nares) of DNA inoculation was used. Only placebo-vaccinated turkeys showed a primary response following challenge, although DNA vaccination didn't generate high antibody titres. Following pcDNA::MOMP vaccination, both T-helper and B-cell memory were primed. However, high maternal antibodies titres affected the induction of vaccine-specific antibody responses as assessed by MOMP-specific antibody levels in ELISA. Cell-mediated immunity was unaltered as demonstrated by the significantly heightened proliferative responses of peripheral blood lymphocytes following vaccination. DNA vaccination could significantly reduce clinical symptoms, pharyngeal and cloacal excretion as well as chlamydophila replication, even in the presence of maternal antibodies.

Serological and molecular characterization of Chlamydophila psittaci strains using serovar-specific monoclonal antibodies and ompA sequence analysis.

In the present study, 21 avian Chlamydophila psittaci field isolates from 4 different European countries (Belgium, Germany, Italy and The Netherlands) were characterized using serovar-specific monoclonal antibodies as well as ompA sequence analysis, enabling the comparison between the two characterization methods for future epidemiological studies. The 21 European isolates included 6 isolates from the order Psittaciformes, 6 isolates from the Anseriformes, 5 isolates from the order Columbiformes and 4 Galliformes respectively. Only 19 on 21 isolates could be serotyped while all isolates were successfully genotyped. In addition, genotyping revealed the presence of mixed infections in 5 on 21 isolates while serotyping could only detect one of these 5 mixed infections. Interestingly, genotyping indicated the existence of a new genotype designated E/B. The E/B genotype is closely related to the genotypes A, B and E but the ompA gene of E/B strains shows a guanosine on position 1006 and 1021 in combination with a cytidine on position 1022 to be unique. Genotype E/B isolates reacted with both the serovar E- and B-specific monoclonal antibody leading to the conclusion of a mixed infection while only one specific ompA sequence was present in the sample. For epidemiological studies genotyping by use of ompA sequence analysis is to be preferred as it is more sensitive than serotyping and can distinguish genotype B, E and E/B strains.

Protection of turkeys against Chlamydophila psittaci challenge by parenteral and mucosal inoculations and the effect of turkey interferon-gamma on genetic immunization.

Plasmid DNA (pcDNA1::MOMP A) expressing the major outer membrane protein of an avian Chlamydophila psittaci serovar A strain was tested for its ability to induce protective immunity against challenge with the same C. psittaci serovar. A combined parenteral (intramuscular injection) and mucosal route (DNA drops administered to the nares) of DNA inoculation was compared to three other, different routes of administration (intramuscular inoculation, DNA drops administered to the nares and aerosol immunization). In addition, the effect of turkey interferon gamma (tIFN-gamma) on intramuscular immunization was evaluated by co-expressing pCIneo::tIFN-gamma. A significant level of protection was observed in turkeys immunized via the combined parenteral/mucosal route, the intramuscular route or by aerosol. Severe clinical signs and lesions were observed in the non-vaccinated control groups, in 80% of turkeys inoculated with a mixture of pcDNA1::MOMP A and pCIneo::tIFN-gamma, and in 60% of turkeys vaccinated with DNA drops administered to the nares. The use of MOMP-based DNA vaccination as a means of preventing severe clinical signs and lesions in a turkey model of C. psittaci infection was demonstrated, as was down-regulation of the immune response by co-expression of tIFN-gamma.

Short-term antihypertensive medication does not exacerbate sleep-disordered breathing in newly diagnosed hypertensive patients.

It has been speculated for some time that various antihypertensive medications may have a deleterious effect on respiration during sleep and thereby enhance the apparent association between hypertension and sleep apnea/hypopnea (SAH). However, there are few data to support this contention. The present study used a double-blind, randomized, cross-over design to contrast the effects of 6 weeks treatment with alpha-methyldopa and the combination of hydrochlorothiazide and amiloride with that of amlodipine and the combined diuretics in a group of 24 newly diagnosed patients with primary hypertension. All-night polysomnography was performed before the initiation of therapy (baseline) and at the end of the two treatment periods. Respiratory variables failed to reveal any significant differences between the treatments and baseline, or between the two different treatment regimens. The two treatment regimens achieved similar reductions in blood pressure. The prevalence of SAH was 25% before treatment, which is comparable to a prevalence of 20% in a similar group drawn from the same population but receiving various antihypertensive medications. The findings of this study are in agreement with previous reports using other classes of antihypertensive drugs that also failed to detect any tendency for increases in nocturnal respiratory disturbance indices over assessment periods of 8 weeks or shorter.

Hypertension and sleep apnea in black South Africans. A case control study.

Despite relatively consistent findings that patients with hypertension have higher than anticipated prevalences of sleep apnea/hypopnea (SAH), inadequately controlled factors such as age and obesity have been implicated as possibly accounting for these findings. All-night polysomnograms were performed on 20 hypertensive black South Africans, a group with increased risk for this disease. They were matched with a control group of black subjects in respect of age, gender, body mass index (BMI), neck circumference and scores on a sleep questionnaire. While the groups failed to differ significantly in terms of demographic variables, nor in regard to 8/9 anthropometric measures, the hypertensive group had a significantly higher apnea/hypopnea index (AHI) (P = .01), longer duration of AH (P = .01) and lower mean minimum arterial oxygen saturation levels (P = .005). Of the anthropometric measures, only age and neck circumference were found to be cofactors for AHI and were accounted for in the analysis. Five of the hypertensive patients and two of the controls had an AHI > 10, giving a prevalence odds ratio of 3 (95% confidence interval: 0.66-14.50). The present study appears to be the first in black African subjects and with prevalence findings largely comparable to those obtained in other ethnic groups. There was a trend for more severe SAH to occur in this subgroup of five hypertensives (AHI = 14-30) than in controls (maximum AHI = 12). While data are lacking to link antihypertensive medication to SAH in humans, further study is necessary before discarding this factor.

Selected risk factors for coronary heart disease in male scholars from the major South African population groups.

A number of risk factors for coronary heart disease (CHD) in 7 groups of South African male scholars aged between 15 and 20 years were surveyed. Selection of the groups was based on socioeconomic status and comprised urban and rural blacks, Indians of higher and lower socio-economic status, coloureds of higher and lower socioeconomic status, and middle-class whites. Both Indian groups, both coloured groups and the whites had a much greater prevalence and severity of CHD risk factors than the two black groups. This held for total cholesterol, low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), the HDLC/LDLC ratio, apolipoprotein B, apolipoprotein A-I, insulin, fibrinogen and mass. One exception was lipoprotein a, levels of which were higher in both black groups. In general the CHD risk factor profile was worse in the higher socio-economic groups, and it also tended to be worse in urban than in rural blacks. These findings stress the need to reduce CHD risk factors in our developed populations and to prevent their emergence in our developing peoples.