Modelling of factors influencing the effect of osmotic solution on reduction of selected microorganisms.

AIMS: The goal of this research is to model the effects of two osmotic solutions factors on the reduction of selected microorganisms, and to assess the application in osmotic dehydration process of animal raw materials from the aspect of microbiological safety. METHODS AND RESULTS: Sugar beet molasses and aquatic osmotic solution were prepared and inoculated with Escherichia coli, Listeria monocytogenes and Salmonella spp. Varied factors of osmotic solutions were: time, temperature and concentration of osmotic solutions. Samples of osmotic solutions were subjected to standard and modified microbiological ISO methods. The result showed that increase in factors had a positive effect on the reduction of microbiological load, while the time of the process was the most influential technological parameter. Number of L. monocytogenes was reduced to <10 CFU per g at the end of the process in the highest concentration of sugar beet molasses at all process temperatures. CONCLUSIONS: Developed mathematical models of reduction ratios for tested microorganisms were statistically significant, allowing good prediction of reduction ratio values based on applied factors. SIGNIFICANCE AND IMPACT OF THE STUDY: Obtained levels of reduction of all tested microorganisms present good base for the production of safe osmotically dehydrated products of animal origin.

Band tail absorption saturation in CdWO4 with 100 fs laser pulses.

The decay kinetics of the excitonic emission of CdWO4 scintillators was studied under excitation by powerful 100 fs laser pulses in the band tail (Urbach) absorption region. A special imaging technique possessing both spatial and temporal resolution provided a unique insight into the Förster dipole-dipole interaction of self-trapped excitons, which is the main cause of the nonlinear quenching of luminescence in this material. In addition, the saturation of phonon-assisted excitonic absorption due to extremely short excitation pulses was discovered. A model describing the evolution of electronic excitations in the conditions of absorption saturation was developed and an earlier model of decay kinetics based on the Förster interaction was extended to include the saturation effect. Compared to the previous studies, a more accurate calculation yields 3.7 nm as the Förster interaction radius. It was shown that exciton-exciton interaction is the main source of scintillation nonproportionality in CdWO4. A quantitative description using a new model of nonproportionality was presented, making use of the corrected value of the Förster radius.

Comparison of behavioral effects of cortexin and cerebrolysin injected into brain ventricles.

We compared central effects of polypeptide preparations cortexin and cerebrolysin injected into brain ventricles of Wistar rats in doses of 1, 10, and 100 microg. Both drugs exhibited moderate psychoactivating effect, the effects cortexin were more pronounced compared to those of cerebrolysin in all tests.

[Cranial bone neoplasm in early triassic amphibia]. / Novoobrazovanie pokrovnykh kostei chereepa rannetriasovoi amfibii.

A neoplasm in cranial bone of an early Triassic amphibian has been investigated. Although no tissue has survived, the cranial flat bone is similar to that in living animals of the same class. Evidence is presented in support of a hypothesis that the neoplasm is a skeletal tumor which consists of non-functional bone and looks like an atypical tumorous bone of skeletal origin. It was identified as a parostotic osteosarcoma on the basis of macro- and microscopic and X-ray examination.

Investigation of kinetics of zinc biosorption by Saccharomyces cerevisiae cells.

The highest amount of zinc (approximately 90%) is bound after 3 h of contact at low initial (total) concentrations of zinc in yeast broth, 2.0-16.0 g/l at 10-30 degrees C. The equilibrium between bound and free zinc ions is established after 6 h of contact time, independently on total zinc concentration in yeast milk. No bigger changes of content of zinc bound to yeast cells was determined at 10 degrees C and 30 degrees C. 40% of bound zinc in the equilibrium state is bound during the first 15 min of contact of zinc ions and yeast cells at all initial (total) zinc concentrations in yeast milk both at 10 degrees C and 30 degrees C. The KEKAM (Kolmogorov-Erofeev-Kozeeva-Avrami-Mampel) equation can be used for the description of kinetics of zinc biosorption by yeast cells, for the ranges of zinc concentration of 2.0-16.0 g/l at 30 degrees C (mean correlation coefficient 0.96) and 10.0-16.0 g/l at 10 degrees C (mean correlation coefficient 0.95).

Utilization of cyanobacteria in photobioreactors for orthophosphate removal from water.

The effectiveness of photosynthetic free-living and polyurethane foam (PU) immobilized Anabaena variabilis cells for removal of orthophosphate (P) from water in batch cultures and in a photobioreactor was studied. Immobilization in PU foams was found to have a positive effect on P uptake by cyanobacteria in batch cultures. The efficiency of P uptake by immobilized cells was higher than by free-living cells. A laboratory scale photobioreactor was constructed for removal of P from water by the immobilized cyanobacteria. The photobioreactor was designed so that the growth medium (water) from a reservoir was pumped through a photobioreactor column with immobilized cyanobacteria and back to the reservoir. This created a closed system in which it was possible to measure P uptake. No leakage of cells into the photobioreactor medium reservoir was observed during the operation. The immobilized cells incorporated into a photobioreactor column removed P continuously for about 15 d. No measurable uptake was demonstrated after this period. Orthophosphate uptake efficiency of 88-92% was achieved by the photobioreactor.

Intrapartum external cephalic version of footling-breech presentation.

BACKGROUND: External cephalic version is attempted prior to the onset of labor. Women who present in labor with footling breech presentation are usually delivered by cesarean section. We present our experience of external version in women in labor. MATERIAL AND METHODS: External cephalic version was attempted in thirteen patients in labor with footling breech presentation with the breech out of the pelvis. RESULTS: The procedure was successful in twelve of the thirteen patients. Ten of them delivered vaginally. There were no maternal or neonatal complications. CONCLUSIONS: It may be reasonable to attempt external cephalic version in patients in labor prior to performing a cesarean section.

Induction of labor versus expectant management in macrosomia: a randomized study.

OBJECTIVE: Macrosomia at term is associated with increased maternal and neonatal morbidity, including a higher rate of cesarean delivery and shoulder dystocia. Induction of labor has been suggested as a means to prevent further weight gain and improve outcome. The aim of this study was to determine whether or not induction of labor in these cases improves maternal and neonatal outcome. METHODS: Patients at term with an ultrasonic fetal weight estimation of 4000-4500 g were prospectively randomized into two groups: induction of labor (group D and expectant management (group II). Patients with diabetes, a previous cesarean delivery, or nonvertex presentation were excluded. Outcome variables included mode of delivery, arterial cord pH, presence of shoulder dystocia, brachial plexus injury, clavicular fracture, cephalohematoma, and intraventricular hemorrhage. RESULTS: Of 273 patients who were eligible for the study, 134 were randomized to group I and 139 to group II. Parity, gestational age, and fetal weight estimation were similar in the two groups. The neonates of group II patients were significantly heavier (4132.8 +/- 347.4 versus 4062.8 +/- 306.9 g; P = .024). The rate of cesarean delivery was 19.4% in group I and 21.6% in group II patients (not significant [NS]). Cord pH was similar in both groups. Shoulder dystocia was diagnosed in five group I and six group II patients (NS). None developed brachial plexus injury. There were two cases of mild, transient brachial plexus injury in group II patients without documented shoulder dystocia. Mild intraventricular hemorrhage was diagnosed in three of 44 group I and two of 31 group II neonates evaluated (NS). CONCLUSION: In this prospective, randomized study, induction of labor for suspected macrosomia at term did not decrease the rate of cesarean delivery or reduce neonatal morbidity. Ultrasonic estimation of fetal weight between 4000 and 4500 g should not be considered an indication for induction of labor.

Spiral tubular bioreactors for hydrogen production by photosynthetic microorganisms : design and operation.

Spiral tubular bioreactors were constructed out of transparent PVC tubing for H2 production applications. Both a cyanobacterial Anabaena variabilis mutant that lacks uptake hydrogenase activity and the photosynthetic bacterium Rhodobacter sp. CBS were tested in the bioreactors. Continuous H2 photoproduction at an average rate of 19 mL min-2.h-1 was observed using the A. variabilis mutant under an air atmosphere (without argon sparging or application of a partial vacuum). The cyanobacterial photobioreactor was run continuously for over one month with an average efficiency of light energy conversion to H2 of 1.4%. Another H2-producing approach employed a unique type of activity found in a strain of photosynthetic bacteria that shifts CO (and H2O) into H2 (and CO2) in darkness. Continuous dark H2 production by Rhodobacter sp. CBS from CO (in anticipation of using synthesis gas as the future substrate) at rates up to 140 mL . g cdw-1 . h-1 was observed in a bubble-train bioreactor for more than 10 d.

Diagnostic value of transvaginal color Doppler flow in ovarian torsion.

OBJECTIVE: To evaluate the role of Doppler flow in the diagnostic process of ovarian torsion. METHODS: Twenty-two patients who displayed the clinical symptoms of abdominal pain concomitant with an ovarian mass and were scheduled for explorative laparoscopy were enrolled in the study. The cohort was divided into 3 groups: (A) 8 patients with clinical and sonographic evidence of torsion; (B) 8 patients with abdominal pain and sonographic diagnosis of hemorrhagic cyst; and (C) 6 patients with a simple cystic mass who had undergone explorative surgery due to abdominal pain. RESULTS: After Doppler flow imaging, Group A displayed no blood flow within the mass, and surgery confirmed the diagnosis of ovarian torsion. Seven of the 8 group B patients showed ovarian vascular flow (RI = 0.472 +/- 0.067). Only 2 of the 6 Group C patients displayed vascular flow (RI = 0.680 +/- 0.129) within an untwisted cyst, confirmed by laparoscopy. CONCLUSIONS: The combination of Doppler flow imaging with the morphologic assessment improves the diagnostic accuracy of ovarian torsion.

Transvaginal color flow imaging in the diagnosis of ovarian tumors.

Transvaginal ultrasonography and color flow imaging, performed to investigate whether there is any diagnostic advantage, were assessed over a 3 year period in 217 patients with adnexal masses prior to explorative laparotomy. Gray scale sonography and color Doppler flow were performed 1 day prior to surgery. Benign tumors were found in 165 patients and flow was detectable in 82 (49.7%); 14 patients had tumors of low malignant potential, 12 (85.7%) of whom showed detectable flow, and 38 had malignant tumors, in 25 (65.8%) of whom flow was detectable. Blood flow velocity was evaluated by the calculation of the resistance index prior to surgery. Mean resistive index was 0.39 +/- 0.05 for malignant tumors, compared with 0.49 +/- 0.06 and 0.55 +/- 0.07 for the low malignant potential and benign tumors, respectively. These differences were statistically significant (P < 0.01). When a resistive index of 0.47 was considered the cut-off value, the sensitivity was 88% and the specificity was calculated to be 85% (using color Doppler flow as the only diagnostic method). With our large cohort of patients, we demonstration the contribution of color Doppler flow examination in differentiating benign from malignant ovarian tumors prior to surgery.

Ovarian volume in postmenopausal women--suggestions to an ovarian size nomogram for menopausal age.

BACKGROUND: Transvaginal ultrasonography is an accurate and reliable technique for measuring ovarian size. However, there is no consensus as to the normal ovarian size in post-menopausal women. The purpose of this study was to establish normal values for ovarian volume in postmenopausal age. METHODS: A prospective study was undertaken, in which the ovaries of 311 healthy post-menopausal women were examined by transvaginal ultrasonography. Menopausal age ranged from one to more than 15 years. Three dimensions of each ovary were measured and ovarian volume of every menopausal year was calculated. RESULTS: Curvilinear relationships were found between ovarian volume and menopausal age. Ovarian volume (as plotted on the nomogram) shows a progessive decrease from 8.6 +/- 2.3 cm3 in the first menopausal year, to 2.2 +/- 1.4 cm3 after more than 15 years after the menopause. CONCLUSIONS: These data represent a comprehensive characterization of normal ovarian volumes related to postmenopausal age. These baseline values provide the data which will assist the physician to obtain the sonographic diagnosis of abnormal ovarian size, thus eventually establishing early diagnosis of ovarian tumors.

Fetal surveillance. Should it begin at 40 weeks' gestation in a low-risk population?

We evaluated the possible benefits of antepartum surveillance during the 41st week of pregnancy in a low-risk population. Three hundred low-risk patients (study group) underwent a nonstress test (NST) at the beginning of the 41st week of pregnancy. Outcomes in study group patients who delivered during the 41st week were compared to those in 100 similar control patients who were not tested. One antepartum fetal demise occurred in each group: study group rate, 1/300 (0.3%); control group rate, 1/100 (1%), P > .05. During the 41st week, 158 of 300 (53%) study patients and 59 (59%) control patients delivered. Four of 158 (2.5%) study patients had labor induced for the indication of an abnormal antepartum test during the 41st week. Cesarean delivery for distress during the 41st week was performed on 1/157 (0.6%) study and 1/58 (1.7%) control patients (P > .05). No statistically significant improvement in outcome occurred in the study group even though 4 of 300 study group patients required induction of labor for abnormal antepartum testing during the 41st week of gestation. The current practice of not evaluating low-risk pregnancy with an NST until after the completion of 41 weeks is supported by the results of this study.

The potential applications of cyanobacterial photosynthesis for clean technologies.

Natural photosynthesis may be adapted to advantage in the development of clean energy technologies. Efficient biocatalysts that can be used in solar energy conversion technologies are the cyanobacteria. Photobioreactors incorporating cyanobacteria have been used to demonstrate (a) the production of hydrogen gas, (b) the assimilation of CO2 with the production of algal biomass, (c) the excretion of ammonium, and (d) the removal of nitrate and phosphate from contaminated waters.

Antibiotic for cesarean section: the case for 'true' prophylaxis.

OBJECTIVES: To assess prospectively the efficiency and safety of two extended spectrum cephalosporins used as pre-operative prophylaxis in nonelective cesarean sections, and compare the results to those of a third group of patients that received cefamezine post cord clamping. METHODS: Two hundred and forty one patients undergoing a nonscheduled cesarean section were assigned to receive either cefonicid or ceftriaxone prior to skin incision. These patients were followed prospectively for infectious and fetal complications. The outcome of these patients was also compared with another group of 194 patients that received cefamezine prophylaxis post cord clamping, and whose data were collected retrospectively. Chi-square analysis of variance were performed with P < 0.05 considered significant. RESULTS: There were no significant differences in the febrile complications among the two groups of patients that received pre-operative prophylaxis. However, these patients had significantly less wound infections (P = 0.008) and a significantly shorter hospital stay (P < 0.001) than the patients who received their prophylactic antibiotics post cord clamping. CONCLUSIONS: Extended-spectrum cephalosporins, when given pre-operatively, are both effective and safe, and may have an advantage over intra-operative first generation cephalosporins in the reduction of post cesarean section infectious morbidity.

Microhysteroscopy and endometrial biopsy results following failed diagnostic dilatation and curettage in women with postmenopausal bleeding.

OBJECTIVE: The aim of this study was twofold: firstly to evaluate and compare the diagnostic precision of the microhysteroscopy (MH) and endometrial biopsy in a group of menopausal women in whom D&C had failed to obtain an adequate endometrial sample, and secondly to quantitate the value of a hysteroscopy in determining endometrial sampling in these patients. METHODS: A Hamou type II CO2 microhysteroscope (MH) was used to evaluate the endocervical canal and the uterine cavity, followed by endometrial sampling. RESULTS: Thirty-nine women were assessed using MH and endometrial biopsy. Histopathology results were available for diagnosis in 29 of them (74.3%). In the remaining ten patients, the MH diagnosis was atrophic endometrium. Biopsy results corroborated with MH in 86.2% (25/29) of the patients with tissue samples. The analysis (r) of this concordance rate was statistically significant (r = 0.96). Sample results for patients with MH determined pathological and normal endometrium corroborated in 83% and 91%, respectively, inclusive of three cases of endometrial adenocarcinoma. The sensitivity, specificity and predictive values for MH alone were 93.7%, 76.9% and 83.3%, respectively. CONCLUSIONS: These significant results are indicative that this simplified endoscopic method surpasses all blind hospital or office endometrial sampling methods. Therefore, we suggest that MH and endometrial sampling should be the initial assessment tool for any type of indication requiring endometrial and uterine cavity assessment.

Maternal and fetal serum and tissue levels of ceftriaxone following preoperative prophylaxis in emergency cesarean section.

The use of antibiotic prophylaxis in emergency cesarean section has become the standard of care. Concern over fetal exposure has been the reason that antibiotics are traditionally given post cord clamping, but this does not allow adequate antibiotic levels in maternal blood and tissue to be achieved at the stage of incision and during surgery. We evaluated by bioassay maternal and fetal serum and placental ceftriaxone concentrations following the intravenous administration of 1.0 g of ceftriaxone upon the decision to perform cesarean section. The preoperative prophylaxis with ceftriaxone resulted in adequate protective levels in the mother and very low fetal blood levels.

Decrease of aflatoxin B1 in yoghurt and acidified milks.

Fermentation of yoghurt and acidified milks containing aflatoxin B1 (AB1) were studied. AB1 added to milk before fermentation at concentrations of 600, 1000 and 1400 micrograms/kg was reduced in yoghurts (pH 4.0) by 97, 91 and 90%, respectively. Coagulation time was approximately the same as in the controls. Streptococci had longer chains than those in the controls. The main decrease of AB1 occurred during the milk fermentation. A decrease of AB1 (conc. 1000 micrograms/kg) in milks acidified with citric, lactic and acetic acids (pH 4.0) was 90, 84 and 73%, respectively.

The use of PGE2 for induction of labor in parturients with a previous cesarean section scar.

Controversy still dominates the discussion of the correct method for delivering patients with a previous cesarean section (C/S) scar. Although many have abandoned the slogan of "once a cesarean, always a cesarean", repeat cesareans are still the rule in many institutions. We have abandoned this dogma, and are now advancing to new ideas and are promoting a new protocol. Nineteen post-one cesarean section patients were induced on various indications by means of PGE2 pessaries. Close surveillance revealed no complications and 16 were delivered vaginally. All neonates had good Apgar scores, and all scars were found to be intact upon examination. We recommend cautious use of prostaglandins for selected post-cesarean patients.