Analysis of the dielectric relaxation in reduced graphene oxide/epoxy composites materials using the modulus formalism.

This work reports an analysis of the dielectric properties of reduced graphene oxide mixed into epoxy resin, diglycidyl ether of bisphenol A, in the frequency range 10[Formula: see text]-10[Formula: see text] Hz and over the temperature range of 300-400 K, using impedance spectroscopy. For this study, a series of samples were prepared with various filler contents. Using the electric modulus formalism, it has been found that these composites exhibit below and above the percolation threshold [Formula: see text] a critical behavior of the dielectric relaxation phenomenon due to the single [Formula: see text]-relaxation, which is associated with the glass-rubbery transition of the epoxy matrix above the glass transition temperature. The Cole-Cole model of dielectric relaxation was used for modeling the relaxation processes from which we extract the relaxation parameters. The obtained relaxation parameters suggest a behavior close to single relaxation time.

Dielectric spectroscopy of melt-extruded polypropylene and as-grown carbon nanofiber composites.

In this work, different weight contents of as-grown carbon nanofibers (CNFs), produced by chemical vapor deposition, were melt-extruded with polypropylene (PP) and their morphologic, structure and dielectric properties examined. The morphologic analysis reveals that the CNFs are randomly distributed in the form of agglomerates within the PP matrix, whereas the structural results depicted by Raman analysis suggest that the degree of disorder of the as-received CNFs was not affected in the PP/CNF composites. The AC conductivity of PP/CNF composites at room temperature evidenced an insulator-conductor transition in the vicinity of 2 wt.%, corresponding to a remarkable rise of the dielectric permittivity up to [Formula: see text] 12 at 400 Hz, with respect to the neat PP ([Formula: see text] 2.5). Accordingly, the AC conductivity and dielectric permittivity of PP/CNF 2 wt.% composites were evaluated by using power laws and discussed in the framework of the intercluster polarization model. Finally, the complex impedance and Nyquist plots of the PP/CNF composites are analyzed by using equivalent circuit models, consisting of a constant phase element (CPE). The analysis gathered in here aims at contributing to the better understanding of the enhanced dielectric properties of low-conducting polymer composites filled with carbon nanofibers.

Low dose prophylaxis in Tunisian children with haemophilia.

INTRODUCTION: Low dose prophylaxis could be recommended in countries with limited resources. AIM: We report our single centre experience in children with haemophilia. PATIENTS: Fifty-five children were included in our study with a weekly median dose of 30 UI kg-1 given once, twice or thrice a week. Age of initiation of prophylaxis is 5.32 years (0.64-11.44). Outcome assessment used were number of bleeding before and after initiating prophylaxis, haemophilia joint health score (HJHS), functional independence score in haemophilia (FISH) and quality of life with the Haemo-QoL. RESULTS: Reduction of number of bleeding was clear in all patients; HJHS, FISH and Haemo-QOL were satisfactory. CONCLUSION: Low dose prophylaxis is effective and better than on-demand therapy. It should be the starting point for prophylaxis in countries with limited resources.

Impact of sampling origin on molecular detection of high-risk human papillomavirus and oncogene expression.

PURPOSE OF INVESTIGATION: The recognition of high-risk human papillomavirus (HR-HPV) as an etiological agent of cervical cancer has increased the importance of testing for HPV, and this might contribute to better risk stratification. METHODS: Eighty-eight randomly selected cervical cancer specimens including biopsies and their respective smears were used in this study. Control scrapings were obtained from ten healthy women. The presence of HPV16 and HPV18 was investigated using the technique of polymerase chain reaction (PCR) with the specific primers for the L1 region, while mRNA expression of HPV16 E6-E7 was evaluated by a reverse transcription PCR method (RT-PCR). RESULTS: The positivity for the viral genotype was influenced by the quantity of amplified DNA used. In tumor biopsies the higher positivity for HPV16 (54.5%) and HPV18 (15.9%) was obtained using 687.4 ng of DNA. At smears level solely 31.8% of HPV16 was detected using an average DNA quantity of about 157.2 ng. The revelation of HPV types depends on clinicopathologic data; HPV16 was detected more in advanced stages of squamous carcinoma (SC) samples (20% stage I, 62% Stage II and 80% stage III), while HPV18 and double infection were found exclusively at advanced stages of SC and in adenocarcinoma (AC), respectively (60%, 40% stage III SC and 80%, 20% Stage II A and C). The prevalence of HPV16 E6-E7 transcripts was evaluated at tumor biopsy with frequencies of 50%. CONCLUSION: Our data provide prospective evidence that HPV16/18L1 revelation at biopsy toward pathological types is efficient and correlates well with oncogenic transcript findings. Subtle changes in viral oncogene dynamics highlight the presence of other regulating proteins serving as additional biomarkers.

[Therapeutic problems of hydatic cyst in the liver dome: 120 cases]. / Prise en charge des kystes hydatiques du dôme du foie: à propos de 120 cas.

Our work plans to study problems of the hydatic cyst of the dome on the double therapeutic aspect and prognosis through a 120 study cases collected over a period of 19 years. In this retrospective study, the predominance is male 65.5% with an average of age of 36 years. The diagnosis is often carried late to the stage of complication (biliary rupture in 13 cases and pleurale at 4 invalids) or fortuitously. The pain of the right hypochondre is found in 79.16% of cases. The scanner remains the method of choice for the positive diagnosis. The tomography plays an important role in the exact topographic diagnosis and the count of cysts. Cysts were multiple in 41% of cases. The treatment is surgical. We deplore two death in this series and the morbidity was dominated by subphrenic abscess, pleuresie, biliary escapes, the suppuration of the residual cavity and the prolonged hyperthermy.

Serological study in Tunisian cervical cancer patients.

OBJECTIVE: The aim of this study is to use a novel ELISA, based on five recombinant HPV-16 and HPV-18 proteins, for detection HPV-specific antibodies in a case-control study. PATIENTS AND METHODS: L1, E6 and E7 genes have been over expressed in Escherichia coli as double fused proteins. These recombinant proteins were used in a GST-capture ELISA as coating antigens. Human sera were collected from women with cervical cancer. Negative human sera were collected from patients apparently healthy and may be affected by other infectious agents. RESULTS: Most of the sera showed a positive reactivity to at least one of the HPV-16 or HPV-18 proteins (52/71). A percentage of 39.50% of the sera from HPV-16 infected women and 21.12% of the sera from women infected by HPV-18 genotype recognised at least one of the HPV-16 or HPV-18 proteins. Sera showed different reactivity to L1, E6 and E7 antigens, and only a few serum samples reacted to L1, E6 and E7 HPV-16, E6 and E7 HPV-18 (co-infection). Differences of reactivity between cases and controls were significant (P<0.0001). CONCLUSION: This novel ELISA, based on recombinant HPV-16 and HPV-18 antigens, is able to detect antibodies in women infected by HPV genotypes. The assay is easy to perform and has low cost, making it suitable for monitoring the natural history of HPV infections as well as for detecting pre-existing HPV antibodies in women who receive vaccination.

Antibody response for L1, E6, E7 HPV 16, and HPV 18 antigens in Tunisian women with cervical cancer.

Results obtained in the present work indicated that the Luminex assay is more sensitive than ELISA. The reactivity to the early antigens E6 and E7 was 37% versus 42% for HPV 16 and 21% versus 20% for HPV 18 among cervical cancer cases using ELISA. However, these ratios were 44% and 61%, respectively, for E6 and E7 HPV 16 versus 28% and 21% for E6 and E7 HPV 18 when using the Luminex technique. Data also indicated that HPV 16 and HPV 18 showed distinct profiles for the different antigens tested. Finally, the differences in antibody responses between cervical cancer cases and benign cases toward the different antigens were significant.

Antibody response for L1, E6 and E7 HPV 16 and HPV 18 antigens in Tunisian women with cervical cancer and controls.

Results obtained in the present work indicated that the Luminex assay is more sensitive than ELISA. The reactivity to the early antigens E6 and E7 was 37% versus 42% for HPV 16 and 21% versus 20% for HPV 18 among cervical cancer cases using ELISA. However, these ratios were 44% and 61%, respectively, for E6 and E7 HPV 16 versus 28% and 21% for E6 and E7 HPV 18 when using the Luminex technique. Data also indicated that HPV 16 and HPV 18 showed distinct profiles for the different antigens tested. Finally, the differences in antibody responses between cervical cancer cases and benign cases toward the different antigens were significant.

[Complete non-obstetrical uterine inversion]. / Inversion utérine complète non obstétricale.

A rare case of a gynaecologic uterine inversion is reported emphasizing on the exceptional character of the gynecologic uterine inversion and the pathogenic problems which are tackled. Gynaecologic inversion results from a tumor implanted on fundus of the uterus or from the essential atrophy of suspension ligaments of the uterus. Treatment depends on the anatomic type and the stage.

[Multiple cancers. Apropos of a quadruple cancer]. / Les cancers multiples. A propos d'un cancer quadruple.

A woman of 48 years of age presented over a period of twelve years with, successively, a cancer of the rectum, a cancer of the breast, cancer of the scalp and finally of the endometrium without metastases. Her general condition stayed good. We have looked into the nosological, statistical, pathogenic and prognostic features of multiple cancers. It does seem that the hormone state may be the trigger for this polycancerous condition (hyperoestrogenaemia). This was linked to an alimentary factor (obesity) and to a family history of a predisposition to cancer, as our patient was the tissue of a blood-related marriage and a member of a family where the incidence of cancer was 40%. Multiple cancers are 2.42% of all cancers but are mainly double or triple cancers. There are only 20 cases of quadruple cancers in the literature. One can divide these into: Cancers with a short interval between each appearance of simultaneous appearances, which usually occur at an advanced age, due to simple chance and often with a bad prognosis. Cancers that occur at longer intervals in younger people, which are rarer and show a family predisposition or endogenous factors. Their prognosis is as a whole better.

The interaction of the SRA domain of ICBP90 with a novel domain of DNMT1 is involved in the regulation of VEGF gene expression.

Inverted CCAAT box-binding protein of 90 kDa (ICBP90) is over-expressed in several types of cancer, including breast, prostate and lung cancers. In search for proteins that interact with the set and ring-associated (SRA) domain of ICBP90, we used the two-hybrid system and screened a placental cDNA library. Several clones coding for a new domain of DNMT1 were found. The interaction, between the ICBP90 SRA domain and the DNMT1 domain, has been confirmed with purified proteins by glutathione-S-transferase pull-down experiments. We checked whether ICBP90 and DNMT1 are present in the same macro-molecular complexes in Jurkat cells and immortalized human vascular smooth muscle cells (HVTs-SM1). Co-immunoprecipitation experiments showed that ICBP90 and DNMT1 are present in the same molecular complex, which was further confirmed by co-localization experiments as assessed by immunocytochemistry. Downregulation of ICBP90 and DNMT1 decreased VEGF gene expression, a major pro-angiogenic factor, whereas those of p16(INK4A) gene and RB1 gene were significantly enhanced. Together, these results indicate that DNMT1 and ICBP90 are involved in VEGF gene expression, possibly via an interaction of the SRA domain of ICBP90 with a novel domain of DNMT1 and an upregulation of p16(INK4A). They further suggest a new role of ICBP90 in the relationship between histone ubiquitination and DNA methylation in the context of tumoral angiogenesis and tumour suppressor genes silencing.

[Fetal hydrocolpos]. / L'hydrocolpos foetal.

Foetal hydrocolpos is a rare abnormality, which may be detected by antenatal ultrasound, during neonatal clinical examination or during autopsy of the foetus. Foetal prognosis is related to the extent of the initial anatomical abnormality. Foetal hydrocolpos is usually combined with other congenital malformations and is therefore part of a syndrome or combination. A review of the literature was carried out when two cases occurred in the Rabta maternity clinic in Tunis in order to investigate the incidence, diagnostic tools and prognosis of this abnormality.

[Struma ovarii. A case report]. / Goitre ovarien. A propos d'un cas.

Struma ovarii is a rare ovarian tumor composed entirely or in part of thyroid tissue. Pathogenesis is unclear. Diagnosis rests on the histologic study. A case is reported. Specific features of struma ovarii are discussed based on a review of the literature. The treatment is surgical and the outcome generally favorable.