Numerical and experimental investigation of the deviation of microparticles inside the microchannel using the vortices caused by the ICEK phenomenon

One field of study in microfluidics is the control, trapping, and separation of microparticles suspended in fluid. Some of its applications are related to cell handling, virus detection, and so on. One of the new methods in this field is using ICEK phenomena and dielectrophoresis forces. In the present study, considering the ICEK phenomena, the microparticles inside the fluid are deviated in the desired ratio using a novel ICEK microchip. The deviation is such that after the microparticles reach the floating electrode, they are trapped in the ICEK flow vortex and deviated through a secondary channel that was placed crosswise and noncoplanar above the main channel. For simulation verification, an experimental test is done. The method used for making two noncoplanar channels and separating the particles in the desired ratio with a simple ICEK microchip is an innovation of the present study. Moreover, the adjustment of the percentage of separation of microparticles by adjusting the parameters of the applied voltage and fluid inlet velocity is one of the other innovations of the present experimental study. We observed that for input velocities of 150-1200 µm/s with applied voltages of 10-33 V, 100% of the particles can be directed toward the secondary-channel.

Reliability assessment and validation of the post-acne hyperpigmentation index (PAHPI) in a population from Sub-Saharan Africa in Senegal

BACKGROUND

A post-acne hyperpigmentation index (PAHPI) has been developed in the United States to better compare therapeutic modalities. Our aim in this study was to validate the PAHPI score in patients with skin type VI from sub-Saharan Africa.

PATIENTS AND METHODS

The study was conducted in Dakar, Senegal. Twenty-one patients with Fitzpatrick skin type VI, aged 17 to 55 years, presenting hyperpigmentation secondary to acne were included. Ongoing use of skin bleaching products or acne treatments was allowed. Four trained dermatologists rated the patients using the PAHPI. A narrow-band reflectance spectrophotometer (Mexameter MX-18, Cologne, Germany) was used to measure the degree of pigmentation of involved and adjacent skin on 6 representative facial lesions.

RESULTS

The average inter-rater reliability (weighted Kappa) showed substantial agreement for intensity (0.67), moderate agreement for number (0.53) and fair agreement for lesion size (0.28). Inter-rater reliability for the total PAHPI was excellent for both day 1 and day 2 (interclass correlation coefficient of 0.87 and 0.85, respectively; P<0.0001). Intra-rater reliability for total PAHPI ranged from 0.83 to 0.93 (P<0.0001). PAHPI scoring thus demonstrated excellent reliability both between and within raters. The association was moderate to substantial for all raters on both days (range for rho on day 1: 0.531 to 0.815; range for rho on day 2: 0.448 0.762). The correlations between the Mexameter (Courage and Khazaka) measurements and PAHPI scores showed moderate to substantial agreement.

CONCLUSION

Although tested primarily in African American women to date, PAHPI is also valid for patients from sub-Saharan Africa.

Transient deformation and swelling of paper by aqueous co-solvent solutions

Inkjet printing inks frequently contain polar liquids of low volatility such as glycerol or poly(ethylene glycols) in addition to the main solvent water. The deposition of these liquids on paper sheets induces swelling of the cellulose fibers, which leads to an overall, anisotropic deformation of the sheet. We characterized the corresponding strain components by means of a grid projection method and white light interferometry. For pure water, most of the hydroexpansion strain vanishes again after drying is complete. However, for aqueous solutions of non-volatile co-solvents, a large fraction of the deformation persists after the water has evaporated. Because swelling occurs only after liquid enters the cellulose fibers, monitoring the dynamics of expansion provides insight into the pore-fiber distribution of co-solvents. The corresponding timescales of pore-fiber transport strongly depend on the co-solvent concentration, as a sufficient quantity of water is needed to plasticize the fiber walls.

Evaluation of margins in pelvic lymph nodes and prostate radiotherapy and the impact of bladder and rectum on prostate position

PURPOSE

The aims of this study were: determination of the CTV to PTV margins for prostate and pelvic lymph nodes. Investigation of the impact of registration modality (pelvic bones or prostate) on the CTV to PTV margins of pelvic lymph nodes. Investigation of the variations of bladder and rectum over the treatment course. Investigation of the impact of bladder and rectum variations on prostate position.

PATIENTS AND METHODS

This study included 15 patients treated for prostate adenocarcinoma. Daily kilo voltage images and weekly CBCT scans were performed to assess prostate displacements and common and external iliac vessels motion. These data was used to calculate the CTV to PTV margins using Van Herk equation in the setting of a daily bone registration. We also compared the CTV to PTV margins of pelvic lymph nodes according to registration method; based on pelvic bone or prostate. We delineated bladder and rectum on all CBCT scans to assess their variations over treatment course at 4 anatomic levels [1.5cm above pubic bone (PB), superior edge, mid- and inferior edge of PB].

RESULTS

Using Van Herk equation, the prostate CTV to PTV margins (bone registration) were 8.03mm, 5.42mm and 8.73mm in AP, ML and SI direction with more than 97% of prostate displacements were less than 5mm. The CTV to PTV margins ranged from 3.12mm to 3.25mm for external iliac vessels and from 3.12mm to 4.18mm for common iliac vessels. Compared to registration based on prostate alignment, bone registration resulted in an important reduction of the CTV to PTV margins up to 54.3% for external iliac vessels and up to 39.6% for common iliac vessels. There was no significant variation of the mean bladder volume over the treatment course. There was a significant variation of the mean rectal volume before and after the third week of treatment. After the third week, the mean rectal volume seemed to be stable. The uni- and multivariate analysis identified the anterior wall of rectum as independent factor acting on prostate motion in AP direction at 2 levels (superior edge of, mid PB). The right rectal wall influenced the prostate motion in ML direction at inferior edge of PB. The bladder volume tends toward significance as factor acting on prostate motion in AP direction.

CONCLUSIONS

We recommend CTV to PTV margins of 8mm, 6mm and 9mm in AP, ML and SI directions for prostate. And, we suggest 4mm and 5mm for external and common iliac vessels respectively. We also prefer registration based on bony landmarks to minimize bowel irradiation. More CBCT scans should be performed during the first 3weeks and especially the first week to check rectum volume.

Investigation of Photocatalytic Efficiency of Supported CuO Nanoparticles on Natural Zeolite Particles in Photodegradation of Methyl Orange

In the current work, CuO nanoparticles were deposited on natural zeolite's particles to resolve the drawbacks of zeolite catalysis. The synthesized composites were characterized by XRD, SEM, BET, and DRS analyses. The results illustrated that in the 15% CuO composite, CuO nanoparticles with a size of 21 nm are deposited on the surface of the zeolite particles. Deposition of CuO nanoparticles on zeolite's particles decreased the specific surface area from 35 m²/g (pure zeolite) to 28 m²/g (20% CuO composite), and causes a red shift in the absorption edge of the sample to 796 nm for 20% CuO composite. In order to compare the samples' performances in eliminating water pollutants, methyl orange dye removal was investigated. The analyses indicated that the optimum efficiency (85% in 120 min) belongs to zeolite-15% CuO composite with a band gap of 1.70 eV.

Insomnia, sleepiness, anxiety and depression among different types of gamers in African countries

Gaming has increasingly become a part of life in Africa. Currently, no data on gaming disorders or their association with mental disorders exist for African countries. This study for the first time investigated (1) the prevalence of insomnia, excessive daytime sleepiness, anxiety and depression among African gamers, (2) the association between these conditions and gamer types (i.e., non-problematic, engaged, problematic and addicted) and (3) the predictive power of socioeconomic markers (education, age, income, marital status, employment status) on these conditions. 10,566 people from 2 low- (Rwanda, Gabon), 6 lower-middle (Cameroon, Nigeria, Morocco, Tunisia, Senegal, Ivory Coast) and 1 upper-middle income countries (South Africa) completed online questionnaires containing validated measures on insomnia, sleepiness, anxiety, depression and gaming addiction. Results showed our sample of gamers (24 ± 2.8 yrs; 88.64% Male), 30% were addicted, 30% were problematic, 8% were engaged and 32% were non-problematic. Gaming significantly contributed to 86.9% of the variance in insomnia, 82.7% of the variance in daytime sleepiness and 82.3% of the variance in anxiety [p < 0.001]. This study establishes the prevalence of gaming, mood and sleep disorders, in a large African sample. Our results corroborate previous studies, reporting problematic and addicted gamers show poorer health outcomes compared with non-problematic gamers.

RapidArc for centrally recurrent cervical cancer in the vaginal cuff following primary surgical therapy: a case report

Background

Pelvic recurrences of cervical cancer after primary surgical treatment can be potentially cured with radical hysterectomy or chemoradiation therapy. Combined radio-chemotherapy is believed to improve results compared to other option. Currently, RapidArc radiotherapy is considered an excellent technological advance that shows great potential for producing highly conformal doses to treatment volumes.

Case presentation

We present a case of a 67-year-old woman with history of early cervical cancer initially treated by radical laparoscopic hysterectomy. More than 5 years later, the patient presented with a central pelvic vaginal cuff recurrence that is histologically confirmed. Salvage radiotherapy using RapidArc with concurrent cisplatin-based chemotherapy was indicated. A high dose of 70 Gy was delivered to the gross recurrent disease with simultaneous integrated boost (SIB) to the subclinical disease and good sparing of organs at risk especially the rectum and sigmoid.

Conclusions

This case clearly demonstrates a large benefit for salvage RapidArc radiotherapy to central pelvic recurrences of gynecological cancers with an excellent rate of local control and less rate of toxicity.

[Cerebral metastasis of a "ghost" bronchopulmonary tumor]

Carcinoma of unknown primary (CUP) is the metastasis of epithelial malignancy whose origin remains unknown. Bronchial carcinoma is the most common cause (45%), however, in more than a quarter of cases, its origin is unknown and the choice of therapy often justifies a histopathological precision brought by the immuno-histochemistry. We present a rare case of cerebral metastasis, revealing an unknown lung cancer after a comprehensive review. This is a patient aged 53 years, chronic smoker, who presented a year and a half ago a sudden loss of consciousness with afebrile tonic-clonic seizure of spontaneous resolution. Clinical examination was unremarkable. Brain imaging by MRI has objectified the presence of two parietal tissue formations, which stereotactic biopsy with histological and immuno-histochemical favored metastasis of lung adenocarcinoma origin. An etiologic in search of the primitive lung remained negative (chest X-ray of face, chest CT and bronchoscopy with sampling upper gastrointestinal endoscopy). The rest of the etiologic, looking for another primitive, remained negative. The diagnosis of a bronchogenic carcinoma with brain metastasis is therefore withheld. The patient received two brain radiotherapies (gamma kniff) with regression of the two nodular formations. We have not given specific treatment and have called for very close monitoring of the patient who remained stable after 18 months. Through this observation, we stress the interest of the histology and immuno-histochemistry of carcinoma of unknown primary (CUP) to the diagnosis, guide therapy and determine prognosis.

Rheology of particulate suspensions in a Poiseuille flow

Particulate dense suspensions behave as complex fluids. They do not lend themselves easily to analytical solution. We propose an analytical model to mimic this problem. Namely, we consider arrays of long parallel plates which represent a simplification of arrays of chains of spherical particles. This simplified model can be solved analytically. The effect of effective rotation of the spherical particles is taken into account by attributing different velocities on each side of the plate that mimics the fact that particles are subject to shear. This work is an extension of a previous study where particle rotation was disregarded. The flow rate, the dissipation and the apparent viscosity are studied as a function of the underlying structure. For a single plate placed out of the flow center, the viscosity is lower when rotation is taken into account. For two plates, the minimal viscosity corresponds to the situation where the particles are as close as possible to the center and arranged symmetrically with respect to the center. We compute the rheological properties for arbitrary plate positions, and exploit them for a periodic arrangement. For N plates, and in a confined geometry, the viscosity is about twice as small as compared to the situation where rotation is ignored. We have conducted a numerical study of a suspension of spherical particles, and linear chains of spherical particles. The numerical study is in good qualitative and semiquantitative agreement with the analytical theory considering long plates. This agreement highlights the fact that our analytical model captures the essential features of a real suspension. The numerical study is based on a fluid dynamic particle method where the particles are represented by a scalar field having high viscosity inside.

Engineering root exudation of Lotus toward the production of two novel carbon compounds leads to the selection of distinct microbial populations in the rhizosphere

The culture of opine-producing transgenic Lotus plants induces the increase in the rhizosphere of bacterial communities that are able to utilize these molecules as sole carbon source. We used transgenic Lotus plants producing two opines, namely mannopine and nopaline, to characterize the microbial communities directly influenced by the modification of root exudation. We showed that opine-utilizers represent a large community in the rhizosphere of opine-producing transgenic Lotus. This community is composed of at least 12 different bacterial species, one third of which are able to utilize the opine mannopine and two thirds the opine nopaline. Opine utilizers are diverse, belonging to the Gram-positive and -negative bacteria. We described two novel mannopine-utilizing species, Rhizobium and Duganella spp., and five novel nopaline-utilizing species, Duganella, Afipia, Phyllobacterium, Arthrobacter, and Bosea spp. Although opine utilizers mostly belong to the alpha-Proteobacteria, Rhizobiaceae family, there is little overlap between the populations able to utilize each of the two opines produced by the plants. Noticeably, in the rhizosphere of transgenic Lotus, only the opine mannopine favors the growth of Agrobacterium tumefaciens, the bacterium from which opines have been characterized. The diversity of opine utilizers from the rhizosphere of Lotus plants is greater than that observed from any other environment. Therefore, transgenic plants with engineered exudation constitute an excellent tool to isolate and characterize specific microbial populations.

[Central nervous system germinoma: retrospective study of six cases]

PURPOSE

Retrospective analysis of six patients with intracranial germinoma treated in INO and a literature review.

MATERIALS AND METHODS

Six patients were treated from 1993 to 1998, for histologically verified primary intracranial germinoma. Median age was 18 years (range: 14-26 years). All patients received chemo-radiotherapy (4FP + radiotherapy from 30 to 50 Gy).

RESULTS

4 tumours were in complete remission. Two patients have kept non-evolutive residual cyst. Five patients are alive with non-evolutive disease after 15-40 months of follow-up (average: 27 months). One patient was lost to follow-up, 14 months after treatment, without disease.

CONCLUSION

The treatment of intracranial germinoma is currently first line chemotherapy followed by low-dose and limited irradiation.

[Intracranial Hodgkin disease: case report]

Hodgkin disease intracranial lesions are uncommon. We report the case of a 24-year-old man who presented with an intracranial relapse without other evidence of disease 24 months after multiple drug therapy and extended field radiation therapy for stage III Bb type 3 Hodgkin disease. The patient was treated by whole brain irradiation (40 Gy/20 fractions/4 weeks). Six months after completion of therapy, the patient had a second relapse, with bilateral inguinal metastatic nodes, which were treated by a second line polychemotherapy. The patient was free of disease 9 months later.

Sequential or alternating administration of docetaxel (Taxotere) combined with FEC in metastatic breast cancer: a randomised phase II trial

The aim of this study, using a Fleming single-stage design, was to explore the efficacy and safety of Taxotere 100 x mg x m(-2) docetaxel and FEC 75 cyclophosphamide 500 mg x m(-2), fluorouracil 500 x mg x m(-2) and epirubicin 75 mg x m(-2), in alternating and sequential schedules for the first-line treatment of metastatic breast cancer. One hundred and thirty-six women were randomly allocated, to one of three treatment regimens: DTX 100 plus FEC 75, alternated for eight courses (ALT); four courses of DTX 100 followed by four courses of FEC 75 (SEQ T); or four courses of FEC 75 followed by four courses of DTX 100 (SEQ F). One hundred and thirty-one women were evaluable for tumour response. Although the treatment outcome was equivalent in the two sequential arms and the alternating regimen (P=0.110, not significant), the response rate was less encouraging in the SEQ F arm (52.3%) than in the other two arms (71.1% for ALT and 70.5% for SEQ T), in which docetaxel was administered first. Time to progression was similar in the ALT, SEQ T and SEQ F arms (9.5, 9.3 and 10.4 months respectively). Grade 3-4 neutropenia was observed in nearly all patients; febrile neutropenia occurred in 9% (ALT), 16% (SEQ T) and 2% (SEQ F) of patients. Few patients (< or =9%) developed grade 3-4 non-haematological toxicities. Relative dose intensity was 97-99% for all regimens. All treatment regimens were active and well tolerated.

A rare case of angiosarcoma of the breast in a man: case report

This is a case report of a 57-year-old man who had primary angiosarcoma of the left breast. Five months after detecting a mass in his breast, he underwent mastectomy with biopsy of the ipsilateral axillary lymph nodes. Three years later, he is still alive without any recurrence. Angiosarcoma of the female breast is rare and exceptional in males. It is a condition with a poor prognosis and there are as yet no established chemotherapeutic regimens.

Primary malignant lymphoma of the ovary: an unusual presentation of a rare disease

Because the outcome of patients with primary ovarian non-Hodgkin's lymphoma (NHL) is controversial, we present the incidental finding of a primary malignant lymphoma of the ovary in a 50-year-old patient. Three and a half years following ablative surgery and adjuvant chemotherapy, the patient is alive and disease free. Ovarian lymphoma is a disease of reportedly poor prognosis. However, many previously reported cases of ovarian lymphoma actually represented ovarian involvement by a more diffuse lymphomatous process. If stringent criteria are used for case selection, true primary ovarian lymphoma is a very rare disease and usually carries a favorable prognosis.

Effect of crop rotation and soil cover on alteration of the soil microflora generated by the culture of transgenic plants producing opines

The culture of transgenic Lotus corniculatus plants producing opines, which are bacterial growth substrates, leads to the selection of rhizospheric bacteria able to utilize these substrates. We have investigated the fate of the opine-utilizing community over time under different experimental conditions following elimination of selective pressure exerted by the transgenic plants. These plants were removed from the soil, which was either left unplanted or replanted with wild-type L. corniculatus or wheat plants. The density of opine-utilizing bacteria in the fallow soils remained essentially unchanged throughout the experiment, regardless of the soil of origin (soil planted with wild-type or transgenic plants). When wild-type Lotus plants were used to replace their transgenic counterparts, only the bacterial populations able to utilize the opines were affected. Long-term changes affecting the opine-utilizing bacterial community on Lotus roots was dependent upon the opine studied. The concentration of nopaline utilizers decreased, upon replacement of the transgenic plants, to a level similar to that of normal plants, while the concentration of mannopine utilizers decreased to levels intermediate between transgenic and normal plants. These data indicate that: (i) the opine-utilizing bacterial populations can be controlled in the rhizosphere via plant-exudate engineering; (ii) the interaction between the engineered plants and their root-associated micro-organisms is transgene specific; and (iii) alterations induced by the cultivation of transgenic plants may sometimes be persistent. Furthermore, opine-utilizing bacterial populations can be controlled by crop rotation. Therefore, favouring the growth of a rhizobacterium of agronomic interest via an opine-based strategy appears feasible.

[Paratesticular malignant mesothelioma. Presentation of a case]

We report a case of malignant mesothelioma of tunica vaginalis in a 65-year-old man. The clinical course was marked by local relapse and distant metastases. Based on a review of the literature, the authors discuss the clinical, epidemiological and therapeutic aspects.

[Non Hodgkin's malignant lymphoma of the uterine cervix. Apropos of a case]

The authors report a case of a 61-year-old woman presenting a primary cervical non Hodgkin's lymphoma, FIGO stage IIIA and Ann Arbor stage IE. The patient was successfully treated by combination of multiple drug therapy and pelvic external radiation therapy. Twenty-eight months later, the patient is in good general health and complete remission.

Electron microscopic immunocytochemical localization of proline-rich proteins in normal mouse parotid salivary glands

Rabbit polyclonal antibodies against isoproterenol-induced mouse proline-rich proteins (PRPs) were used to localize PRPs in the parotid salivary glands of normal adult BALB/c mice. The antibodies recognized both acidic-type and basic-type PRPs. Immunoblotting experiments revealed that the glands contained an acidic-type and a basic-type PRP. Parotid gland tissue was fixed with Karnosky's fixative and embedded in Lowicryl resin at low temperature. PRPs were localized at the electron microscope level using an indirect post-embedding staining technique with protein A-gold. The secretion granules of the acinar cells were strongly labelled. Pre-absorption of the antibody with purified acidic-type and basic-type PRPs indicated that the basic-type PRP is mainly located at the periphery of the granules but that the acidic-type PRP is more evenly distributed within the granules. Pre-absorption of the antibody with alpha-amylase did not affect the staining pattern, suggesting minimal cross-reactivity. PRPs were also detected within the rough endoplasmic reticulum and the Golgi apparatus of acinar cells, within the granules of the proacinar cells and in the lumena of the ducts, but not within the intercalated or striated duct cell granules.

Isoprenaline-induced and constitutive members of a proline-rich protein sub-group from mouse parotid glands studied with monoclonal antibody NAL1

Members of the proline-rich protein (PRP) family of mouse parotid glands were analysed before and after stimulation with the beta-agonist isoprenaline by using a monoclonal antibody raised against the induced PRP A3(0) (GP-27). Antibody NAL1 reacted strongly with isoprenaline-induced B-type PRP precursors and their salivary counterparts, but not against the A-type PRPs A1(0) (Gp-66) and A2(0) (GP-45) or human salivary proteins, and it is likely that NAL1 recognizes a proline-rich repeat variant unique to this group of rodent PRPs. PRP-related antigens were observed in the parotid glands (N1(0) and N2(0] and saliva of normal mice. The antigens were located immunocytochemically in secretory granules of parotid acinar cells of both normal and isoprenaline-stimulated mice. The total amount of PRP antigens increased 16-fold from 2.5 to 40% of parotid protein after 10 days of isoprenaline treatment, as estimated by enzyme-linked immunosorbent assay. Immunoblotting showed that new PRP species appeared during the period of increase. After treatment with isoprenaline, B-type PRPs appeared first, followed by A3(0) and another member of the family. These results show that the mouse PRP family is larger than previously thought and can be divided immunologically into sub-groups. That a subset of PRPs are produced in the normal mouse indicates that there is differential beta-adrenergic regulation within the family, and also has implications for the role of PRPs in the normal maintenance of healthy dentition and other processes.

Relationship between fetal heart rate and umbilical blood flow velocity in term human fetuses during labor

Fourteen pregnant women between 37 and 41 weeks' gestational age, who subsequently were delivered of healthy newborn infants, were studied to examine the effects of spontaneous changes in fetal heart rate on the flow-velocity waveforms in the umbilical artery. The women were in active labor and under epidural anesthesia at the time Doppler measurements were made. There was a significant positive relationship between end-diastolic flow velocity and fetal heart rate. The umbilical artery peak-systolic/end-diastolic ratio was best correlated with the negative reciprocal transformation of the instantaneous fetal heart rate value and end-diastolic flow velocity. No significant correlation was found between fetal heart rate, umbilical artery peak-systolic/end-diastolic ratio, and peak-systolic flow velocity. An upper limit of 3.0 for a normal umbilical artery peak-systolic/end-diastolic ratio was acceptable only if the instantaneous fetal heart rate was greater than or equal to 130 beats/min.

Rupture of retroperitoneal hydatid cyst into the abdominal aorta

We report the case of a retroperitoneal hydatid cyst ruptured into the infrarenal abdominal aorta. Initial treatment consisted of marsupialization of the cyst with patch angioplasty of the aorta. Formation of a false aneurysm led to reoperation for placement of an aortobifemoral bypass, but the patient died postoperatively. In spite of the exceptional character of this location, diagnosis should be suggested routinely in endemic areas when a retroperitoneal mass is discovered. Treatment should be either in situ prosthetic replacement or extra-anatomic exclusion bypass.