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Experiments of continuous alcoholic fermentation of sugarcane juice with flocculating yeast recycle were conducted in a system of two 0.22-L tower bioreactors in series, operated at a range of dilution rates (D 1 = D 2 = 0.27–0.95 h−1), constant recycle ratio (α = F R /F = 4.0) and a sugar concentration in the feed stream (S 0) around 150 g/L. The data obtained in these experimental conditions were used to adjust the parameters of a mathematical model previously developed for the single-stage process. This model considers each of the tower bioreactors as a perfectly mixed continuous reactor and the kinetics of cell growth and product formation takes into account the limitation by substrate and the inhibition by ethanol and biomass, as well as the substrate consumption for cellular maintenance. The model predictions agreed satisfactorily with the measurements taken in both stages of the cascade. The major differences with respect to the kinetic parameters previously estimated for a single-stage system were observed for the maximum specific growth rate, for the inhibition constants of cell growth and for the specific rate of substrate consumption for cell maintenance. Mathematical models were validated and used to simulate alternative operating conditions as well as to analyze the performance of the two-stage process against that of the single-stage process.

The scale-up effects on kinetic parameters and on predictions of a yeast recycle continuous ethanol fermentation model incorporating loss of cell viability were evaluated. The average level of cell viability estimated for large scale was similar to that estimated for small scale, although with a major standard deviation. The values of specific rate of cell viability loss were equal for the two scales. These results were due to the utilization of the same aeration rate for both scales, one of the main factors for cell-viability maintenance. The kinetic parameters were not significantly affected by the scale-up of the fermentation process. Major differences were observed for the maximum specific growth rate and for maximum ethanol concentrations for which, growth and ethanol production are totally inhibited. The scale-up did not result in lack of fit of the mathematical model to the experimental data.

At present, postpartum hemorrhage is still an important cause of maternal mortality and morbidity. When medical therapy has no success, conservative surgical procedures are applied before making a hysterectomy. Three transverse sutures are applied to the entire uterine wall both to the right and the left side of the uterus. Our technique has been applied to 4 women with postpartum hemorrhage secondary to uterine atony. Bleeding was stopped immediately by compressive sutures. The four patients had normal menstruation cycles after delivery and had new pregnancies. No woman had postoperative complications. Uterus compressive suture is an effective alternative to hysterectomy to treat postpartum hemorrhage secondary to atony. This is a simple and quick procedure that preserves fertility.

Abdominal scar recurrence of endometrial carcinoma after abdominal total hysterectomy is very rare. We report a case of a 65-year-old woman who had two recurrences in the abdominal incisional scar after total hysterectomy.A 65-year-old woman underwent total hysterectomy with bilateral salpingo-oophorectomy and pelvic lymphadenectomy because of well-differentiated endometrial adenocarcinoma (Stage IIB). Thus, the patient was treated by external beam radiotherapy. She developed two recurrences in the abdominal incisional scar two and three years after total hysterectomy, respectively. Surgery plus chemotherapy and surgery plus hormonal therapy were used for treatment of the first and second scar recurrence, respectively.It is a very intriguing and controversial biologic question how neoplastic cells can implant and grow in an abdominal scar without other concomitant metastases. We report a review of the literature and the possible mechanism of recurrences in laparotomy wounds.

The term female adnexal tumor of probable Wolffian origin "FATWO" designs this tumor wich arises by the rare persisting remnants of the mesonephric duct (Wolffian duct). About 40 cases have been reported in literature. Few cases of recurrence have been reported, FATWO usually shows no signs of hormonal activity. We report a case of the youngest patient affected by FATWO in October 2002. At laparotomy the left adnexa were deformed by a well-capsulated mass, totally removed and sent to the pathologist with a specimen of peritoneal fluid and of the omentum. The histological examination showed a prevalent tubular structure with focal retiform area, without intraluminal mucines. Immunohistochemical findings of the case reported are similar to those described by other authors, except for inhibin which has not been detected by us. The cytofluorimetry showed the low presence of aneuploid cells, with a very low prolifing component (1%).

To assess CA-125 in defining tumor response in patients treated with paclitaxel.We analyzed 150 women treated for epithelial ovarian carcinoma with platinum or paclitaxel. We compared the patients treated with two agents, using a precise definition of CA-125 response, determined by 50% and 75% reductions, like other authors have published.CA-125 criteria gave response rates very similar to the standard response rates, both for patients treated with platinum (75% vs 63%) and also for those treated with paclitaxel (40% vs 39%). Rates of false-positive prediction of response by CA-125 were also similar for patients treated with these two agents.Precise 50% or 75% CA-125 response criteria are as sensitive as standard criteria for assessing activity of therapy for the ovarian cancers treated with platinum or paclitaxel. We propose that they may be useful in defining response in lieu of or in addition to standard response criteria in clinical trials involving epithelial ovarian cancer.

We present our initial clinical experience with a recently introduced 64-detector computed tomography (64-MDCT) scanner that makes use of a periodic motion of the focal spot in the longitudinal direction (z-flying focal spot), which enables it to reach a final spatial resolution of 0.4 x 0.4 x 0.4 mm(3) and a temporal resolution of 83 ms.A total of 114 patients (108 men, six women; age range 36-77 years, mean 63.1 years) underwent retrospective electrocardiogram (ECG)-gated examination of the coronary arteries using a 64-MDCT scanner (Somatom Sensation 64, Siemens Medical Solutions, Germany). Acquisition parameters were the following: collimation 64 x 0.6 mm, 800 quality reference milliampere second (mAs), 120 kVp, 0.33-s gantry rotation time and pitch 0.2. Images were acquired in all cases after i.v. administration of 80 ml of contrast agent (Iomeron 400 mgI/dl, Bracco, Italy) + 30 ml of saline at 4 /s and delay time determined using a bolus triggering technique. Oral betablockers were administered to patients with heart rate (HR)75 bpm. To reduce radiation exposure, an automatic exposure control system was applied in all cases to adapt tube current to patient size and anatomic shape (CARE Dose 4D, Siemens Medical Solutions, Germany). The optimal temporal window for raw data reconstruction was chosen from an initial preview of images reconstructed with different phase settings (range 0%-95% RR interval with 5% gap) at a selected anatomical level in the mid part of the right coronary artery. CT dose index volume and effective dose were quantified in all patients using dedicated software.Mean HR recorded during image acquisition was 65.6+/-19.2 bmp (range: 44-96 bmp), and beta-blockers were administered to 16/114 patients (14.0%). Technical adequacy was achieved in all patients but two (2/114; 1.7%). In patients with HR60 bmp, the best reconstruction intervals were identified in the end-systolic (30%-35% of the RR interval) and end-diastolic (60%-65% of the RR interval) phases; with faster HR (80 bmp), high image quality was observed in end-systole (30%-35% of the RR interval). Mean CT dose index (CTDI) volume was 36.53+/-8.30 mGy per patient. In comparison with a conventional examination with fixed mAs, the use of the CARE Dose 4D system provided a 33.3% CTDI volume reduction (p0.001). Mean effective dose was 9.5+/-3.4 millisievert (mSv) per patient (range 7.1-17.7).The 64-MDCT scanner diagnostic performance for coronary CT angiography is further improved with better spatial and temporal resolution and faster scan times; besides, initial clinical results are promising. The use of dose-reducing acquisition techniques is mandatory to limit radiation exposure to the patient.

The aim of this study was to determine the incidence of AGUS (atypical glandular cells of undetermined significance), ASCUS (atypical squamous cells of undetermined significance) and SIL (squamous intraepithelial lesion) in the cytologic diagnosis in pre- and postmenopausal women.We did a retrospective study selecting 183 patients who were screened for cervical pathology. Ninety-six patients were in postmenopausal age. We determined the incidence of cytologic abnormalities defined as ASCUS, SIL, and AGUS in pre- and postmenopausal women.We expected a marked incidence of low-grade SILs in the fertile population, while the postmenopausal group was thought to be affected more by AGUS and ASCUS. We obtained different results. In our population study, premenopausal women presented more AGUS and ASCUS; the two subgroups presented the same incidence of low-grade SILs; postmenopausal women were more affected by high-grade SILs.The significance of the new categories introduced by the Bethesda System is still uncertain for different authors. As we look to the future new markers that more specifically identify individuals at-risk can be expected.

Discrimination between different rival models for describing the inhibitory effect of ethanol both on yeast growth and on fermentation was studied for a continuous process of alcoholic fermentation in a tower reactor with recycling of flocculating cells. Models tested include linear, parabolic, hyperbolic, exponential, and generalized nonlinear power-law types. The best expressions were identified under the criteria that all the kinetic parameters should assume acceptable values in a feasible range and should result in the best fit of the experimental data. The kinetic parameters were estimated from steady-state data of several sugar concentrations in feeding stream (S0 = 160, 170, 180, 190, 200 g/L), constant dilution rate (D = 0.2 h-1), recycle ratio (alpha = 13.6), and temperature (T = 30 degrees C). The best model for the yeast growth was of power-law type, whereas for the product formation the best model was of linear type. These models were able to reproduce the trends of the process variables satisfactorily.

The influence of different substrate concentrations on the performance of a continuous system of alcohol production by fermentation using a tower reactor with recycling of flocculating yeasts was investigated. All experiments were carried out using a flocculating yeast strain IR-2, isolated from fermented food, and identified as Saccharomyces cerevisiae. Cane sugar juice was used as a substrate with sugar concentrations of 160, 170, 180, 190, and 200 g/L. Constant values of dilution rate, 0.20 h-1, temperature, 30 degrees C, and pH 3.3, were used. The performance of the reactor was observed to be efficient with high substrate concentrations. Maximum productivities of 18 g/L/h 99% substrate conversion and ethanol concentrations of 90 g/L were obtained using 200 g/L of sugar in the feedstock. For substrate concentrations of 160 g/L, a maximum yield of 0.45 g of ethanol/g of sugar was observed or 90% of the theoretical value.

The concept of loss of cell viability was introduced into a model previously developed for a continuous alcoholic fermentation process in a tower reactor with recycling of flocculating yeasts. The two models take into account substrate limitation and inhibition phenomena linked to ethanol and biomass. The kinetic parameters were estimated from steady-state data of several sugar concentrations in feeding stream and constant dilution rate, recycle ratio and temperature. Some parameters of the modified model (maximum specific rates) were significantly different from those estimated with the original model while others (inhibition parameters) remained practically unchanged. Both models provided similar predictions and were equally suitable for modelling of the process.

An unsegregated and unstructured model developed for a small-scale process of ethanol production in a tower reactor with cell recycle was applied to describe the experimental data obtained in a large-scale process. The model was developed considering the following points: reactor hydrodynamic behavior analogous to that of ideal CSTR, substrate limitation, inhibition phenomena linked both to ethanol and to biomass, absence of fermentation in the settler, and no loss of cell viability. The scale-up criterion consisted in maintaining an identical relation settler volume/fermentor volume on the two scales. All large-scale experiments were carried out using a flocculating yeast strain IR-2, isolated from fermented food, and identified as Saccharomyces cerevisiae. Sugarcane juice was used as the substrate source with sugar concentrations of 150 g/l. Different values of dilution rate and recycle ratio were employed (D = 0.11–0.33 h−1, α = 5.4–18.0) and the temperature was of 32 °C. The kinetic parameters were similar on both scales and the model predictions agreed well with the large-scale experimental data.

The authors carried out a coprological survey in Pemba Island, analysing, by modified Ritchie technique, 413 stools samples. The specimens were collected among the population from apparently healthy subjects chosen at random in a number equal to 2% of the whole population. The examined subjects were divided in 3 age groups, 211 were males, 202 females. The following results were obtained (in order of prevalence): a) Protozoa: Entamoeba coli 35.6%, Giardia intestinalis 5.6%, Endolimax nana 4.3%, E. histolytica 3.1%, Chilomastix mesnili 2.9%, Iodamoeba buetschlii 4.3%, E. hartmanni 0.7%; b) Helminths: Trichuris trichiura 87.9%, Ancylostomatidae 67.5%, Ascaris lumbricoides 39.7%, Strongyloides stercoralis 18.9%, Schistosoma haematobium 1.9%, S. mansoni 0.2%, S. fuelleborni 0.2%, Enterobius vermicularis 0.2%. The high moisture of soil and the rain distribution during the year could be favouring the high prevalence of T. trichiura and Ancylostomatidae. The case of schistosomiasis due to S. mansoni reported, seems to be imported from the Mainland, while the case of S. fuelleborni could be autochtonous. Totally, 392 subjects (94.4%) were found positive for pathogenic species (Helminths and Protozoa).

In 1983 the authors carried out a survey in the Democratic Republic of São Tomé and Principe, analysing 1050 specimens of stools collected among the population from apparently healthy subjects chosen at random and in a number proportional to the distribution of the population in the regions of the country (about 1% of the population was examined). The examined subjects were divided into 3 age groups (0-3, 4-12, more than 12 years old), to have homogeneous groups in relation principally to modalities of life and nutritional patterns. There were 488 male subjects and 562 females. The survey was preceded by a sensitization of the people to the problem of intestinal parasites and by two preliminary surveys about the number of existing latrines and about people's believes and attitudes in relation to helmintiasis. The tests were made according to the modified Ritchie technique on fecal specimens preserved with 10% formol solution. The following results were found: a) Protozoa: Entamoeba coli, 43.0%; Iodamoeba buetschlii, 9.0%; Giardia intestinalis, 8.8%; Endolimax nana, 7.0%; E. histolytica, 5.5%; E. hartmanni, 2.5%; Chilomastix mesnili, 2.3%; Trichomonas intestinalis, 0.2%; Balantidium coli, 0.1%. b) Helminths: Trichuris trichiura, 87.7%; Ascaris lumbricoides, 64.3%; Ancylostomatidae, 40.5%; Strongyloides stercoralis, 6.8%; Hymenolepis diminuta, 0.3%; H. nana, 0.2%; Schistosoma haematobium, 0.2%. In 28.2% of the specimens (with more than 50% of subjects in some villages) eggs of Heterophyidae were found, very similar to Metagonimus yokogawai, but not yet identified by us, with the following characteristics: elliptical shape, average size 25 mu (22.2-27.7) X 18.5 mu (17-21), thick wall, operculum difficult to see, not sticking out from the outline but visible by focusing being in a different refractiveness, presence of a small polar knob, colour slightly brownish, asymmetric miracidium. Further investigations are necessary to identify the species of this trematode and to understand if it is a true human parasite or a pseudoparasite. The general results show the existence of a heavy fecal pollution all over the territory of the D.R. of São Tomé and Principe, connected with unhygienic life conditions, dangerous for health. This suggests to start urgently a sanitation program.

The presence of Cryptosporidium sp. and Isospora suis is reported for the first time in piglets in Italy, in the province of Mantova: the first one has been found in 1 and the second one in 39 out of 200 litters. Two piglets, respectively 20-day-old and 24-day-old, were experimentally infected with Cryptosporidium sp. oocysts from naturally infected calves, without clinical signs.

A coprological survey was carried out in 1982-1983 in East Boè and in Canhabaque Island, (Bijagòs Islands), where 289 and 288 specimens of stools, respectively, have been collected. The samples were taken from apparently healthy subjects, of both sexes and of different age groups. The tests were made according to the modified Ritchie technique. The following results were obtained: A) East Boè: 1) Protozoa: E. coli 68.9%, E. nana 24.6%, G. intestinalis 8.7%, I. buetschlii 5.9%, E. histolytica 1.7%, E. hartmanni 0.7%, T. intestinalis 0.7%. b) Helminths: Ancylostomatidae 69.2%, T. trichiura 38.4%, S. stercoralis 6.2%, Taenia sp. 1.7%, H. nana 0.7%, S. haematobium 0.7%, S. mansoni 0.7%, S. fuelleborni 0.7%. B) Canhabaque: a) Protozoa: E. coli 85.1%, I. buetschlii 14.9%, E. nana 12.5%, G. intestinalis 8.3%, C. mesnili 7.3%, E. hartmanni 1.4%, E. histolytica 1.0%, T. intestinalis 0.4%. b) Helminths: Ancylostomatidae 87.9%, T. trichiura 9.4%, S. stercoralis 7.9%, S. fuelleborni 2.8%, Trichostrongylus sp. 1.4%, A. lumbricoides 0.7%, H. nana 0.4%. Eggs of Capillaria sp. probably pseudoparasites, were found in 8.7% of samples. The high prevalence of Ancylostomatidae infections appears to be related to the heavy fecal pollution all over the examined territory. The utilization of antihelminthic drug of popular medicine, which has a specific action on A. lumbricoides, could explain the lack and the low prevalence, respectively, of A. lumbricoides infections in both examined areas. In the past, other authors emphasized the low prevalence of this parasite for other Guinea Bissau regions which have a different geomorfological constitution. The cases of S. fuelleborni and H. nana are the first reported for Guinea Bissau.