ADENOID CYSTIC CARCINOMA MISINTERPRETED AS ANTROCHOANAL POLYP: A RARE PRESENTATION.

Adenoid cystic Carcnoma (ACC) is an uncommon malignant tumour accounting for <1% of all oral and maxillofacial tumors. However, in the sinonasal tract, ACC is the most common salivary gland tumor. The sinonasal ACC is asymptomatic initially or causes non-specific symptoms that are similar to those caused by inflammatory sinus disease and local neurological symptoms such as trigeminal neuralgia in advance stage due to perineural invasion by the tumour.We present a case of 35-year-old female who presented with complaints of nasal obstruction and headache. CT scans revealed an antrochoanal polyp without any bony involvement. The histopathological examination revealed unremarkable respiratory epithelium with underlying sheets and acini of small hyperchromatic cells with hyaline-like material in the lumina, confirming adenoid cystic carcinoma. The highlight of this case is that sinonasal polyps are not always inflammatory in origin, these can be neoplastic also.

Bioconversion of water-hyacinth (Eichhornia crassipes) hemicellulose acid hydrolysate to motor fuel ethanol by xylose-fermenting yeast.

Water-hyacinth (Eichhornia crassipes) hemicellulose acid hydrolysate has been utilized as a substrate for ethanol production using Pichia stipitis NRRL Y-7124. Hydrolysate fermentability was considerable improved by boiling, and overliming up to pH 10.0 with solid Ca(OH)(2) in combination with sodium sulfite. The percent total sugar utilized and ethanol yield (Y(p/s)) for the untreated hydrolysate were 20.15+/-0.17% and 0.19+/-0.003 g(p) g(s)(-1), respectively, compared with 76.0+/-0.32% and 0.35 g(p) g(s)(-1), respectively for the treated material. The fermentation was very effective at an aeration rate of 0.02 v/v/m, temperature 30+/-0.2 degrees C and pH 6.0+/-0.2. However, the volumetric productivity (Q(p)) was still considerably less than observed in a simulated synthetic hydrolysate medium with a sugar composition similar to the hemicellulose acid hydrolysate. L-Arabinose was not fermented but assimilated. The presence of acetic acid in the hydrolysate decreased the ethanol yield and productivity considerably.

The influence of nutritional and environmental conditions on the accumulation of poly-beta-hydroxybutyrate in Bacillus mycoides RLJ B-017.

AIMS: To optimize the nutritional and environmental conditions for growth of and poly-beta-hydroxybutyrate (PHB) accumulation in Bacillus mycoides RLJ B-017. METHODS AND RESULTS: An isolate, identified as B. mycoides, was grown on different sources of carbon and nitrogen. Among these, sucrose, beef extract and di-ammonium sulphate were found to be the most suitable for growth and PHB accumulation. The overall maximum value of PHB (%) in cells, PHB yield (Yp/s) and productivities (Qp and qp) were 69.4 +/- 0.4% dry cell weight (DCW), 0.21 gp gS(-1), 0.104 +/- 0.012 gp l(-1) h(-1) and 0.03 gp gx(-1) h(-1), respectively when grown in a medium containing 20 gs l(-1) sucrose, supplemented with di-ammonium sulphate. The addition of beef extract increased the value of PHB (%) in cells, PHB yield and productivities by 17.58 +/- 0,3, 23.8, 19.23 +/- 0.3 and 13.8 +/- 0.2% , respectively. The overall maximum values of PHB (% DCW), PHB yield and productivities were obtained at pH 7.0 +/- 0 .1, temperature 30 +/- 0.5 degrees C, agitation 650 rev min(-1) and oxygen transfer rate 3.8 mmol O(2) l(-1) h(-1). CONCLUSIONS: Sucrose, glucose and fructose were found to be more suitable for cell growth and PHB accumulation, but sucrose was less expensive than glucose. Among the nitrogen sources, beef extract and di-ammonium sulphate promoted PHB synthesis. The accumulation of PHB was observed to be growth associated. SIGNIFICANCE AND IMPACT OF THE STUDY: Gram-positive bacteria have not been reported to accumulate large amounts of polyhydroxyalkanoate and hence have not been considered as potent candidates for industrial production. A number of Bacillus spp. have been reported to accumulate 9-44.5% DCW PHB. By comparison, Bacillus RLJ B-017 contained 69.4 +/- 0.4% DCW PHB. Therefore, this strain has been considered as a potent organism for industrial interest. A relatively high yield of PHB was obtained in this wild strain and PHB synthesis was independent of nutrient limitation. The conditions for the higher PHB yield and productivity will be optimized in the next phase using fed-batch culture.

Ethanol production from hardwood spent sulfite liquor using an adapted strain of Pichia stipitis.

Conditions have been optimized for fermentation of pretreated hardwood spent sulfite liquor (HSSL) using an adapted strain of Pichia stipitis. The pretreatments, consisting of boiling and overliming with Ca(OH)2 of HSSL, to partially remove inhibitors, and adaptation of the yeast strain to HSSL, were both critical for a successful fermentation. Ethanol concentration was increased from 6.7 to 20.2 g l(-1) using adapted P. stipitis (A) and pretreated HSSL. The maximum ethanol yield (Yp/s) and productivity (Qp) were 0.41 g g(-1) and 0.44 g l(-1) h(-1), respectively, at an oxygen transfer rate of 2.0 mmol O2 l(-1) h(-1). The optimized results with this strain were compared to those of other xylose-fermenting yeasts and Saccharomyces cerevisiae (SSL-acclimatized) currently used at an industrial plant for the fermentation of spent sulfite liquor.

Ethanol production from wheat straw hemicellulose hydrolysate by Pichia stipitis.

Ethanol production was evaluated from wheat straw (WS) hemicellulose acid hydrolysate using an adapted and parent strain of Pichia stipitis. NRRL Y-7124. The treatment by boiling and overliming with Ca(OH)(2) significantly improved the fermentability of the hydrolysate. Ethanol yield (Yp/s) and productivity (Qp av) were increased 2.4+/-0.10 and 5.7+/-0.24 folds, respectively, compared to neutralized hydrolysate. Adaptation of the yeast to the hydrolysate resulted further improvement in yield and productivity. The maximum yield was 0.41+/-0.01 g(p) g(s)(-1), equivalent to 80.4+/-0.55% theoretical conversion efficiency. Acetic acid, furfurals and lignins present in the hydrolysate were inhibitory to microbial growth and ethanol production. The addition of these inhibitory components individually or in various combinations at a concentrations similar to that found in hydrolysate to simulated medium resulted a reduction in ethanol yield (Yp/s) and productivity (Qp av). The hydrolysate used had the following composition (expressed in g x l(-1)): xylose 12.8+/-0.25; glucose 1.7+/-0.3; arabinose 2.6+/-0.21 and acetic acid 2.7+/-0.33.

Development of xylose-fermenting yeast Pichia stipitis for ethanol production through adaptation on hardwood hemicellulose acid prehydrolysate.

AIMS: The objective of this study was to develop a mutant from Pichia stipitis NRRL Y-7124, tolerant of high concentrations of acetic acid and other inhibitory components present in acid hydrolysates, to improve ethanol yield and productivity. METHODS AND RESULTS: The mutant was developed through adaptation in acid hydrolysate supplemented with nutrients and minerals at 30 +/- 0.5 degrees C. When it was tested for its ability to ferment acid hydrolysate, it showed shorter fermentation time, better tolerance to acid and could ferment at lower pH. The ethanol yield (Yp/s) and productivity (Qp) were increased 1.6- and 2.1-fold, respectively. CONCLUSION: The development of a mutant and its tolerance to acetic acid present in hydrolysates is described. The selected mutant is capable of fermenting both hexoses and pentoses present in hydrolysate at lower pH in comparison with the parent strain. SIGNIFICANCE AND IMPACT OF THE STUDY: The mutant could play a significant role in reducing environmental pollution by using sugars present in pulp mill effluent and, at the same time, could produce a marketable liquid fuel ethanol.

Growth-associated production of poly-3-hydroxybutyrate by Bacillus mycoides.

Bacillus mycoides strain RIJ B-017, a growth-associated poly-3-hydroxybutyrate (PHB) producer was grown on sucrose-containing media. PHB accumulated in cells up to 72% of dry cell mass. The overall maximum value of PHB yield (Yp/s) and productivities (Qp and qp) 250 mgp/gs, 120 mgp L-1 h-1 and 30 mgp gx-1 h-1, respectively, were obtained at 15 g/L sucrose. Differential scanning calorimeter heating curve showed two peaks, one at 95.9 degrees C and another at 165.4 degrees C with a shoulder around 154.6 degrees C. The viscosity-average molar mass in chloroform at 27 degrees C was 505 kDa. The carbon content of PHB was 55.4% of the mass.

Use of cervical ultrasonography in prediction of spontaneous preterm birth in twin gestations.

OBJECTIVE: This study was undertaken to compare various ultrasonographic cervical parameters with respect to ability to predict spontaneous preterm birth in twin gestations. STUDY DESIGN: This prospective study involved 131 women carrying twins who were longitudinally evaluated on 524 occasions between 15 and 28 weeks' gestation with transvaginal cervical ultrasonography and transfundal pressure. The following cervical parameters were obtained: funnel width and length, cervical length, percentage of funneling, and cervical index. Receiver operating characteristic curve analysis was used to determine the ultrasonographic cervical parameter evaluated at 15 to 20 weeks' gestation, 21 to 24 weeks' gestation, and 25 to 28 weeks' gestation that were best for prediction of spontaneous preterm birth at <28 weeks' gestation, <30 weeks' gestation, <32 weeks' gestation, and <34 weeks' gestation. RESULTS: The median gestational age at delivery was 36 weeks' gestation (range, 21-41 weeks' gestation). Receiver operating characteristic curve analysis indicted that a cervical length of < or =2.0 cm, regardless of gestational age category at cervical measurement, was at least as good as other ultrasonographic cervical parameters at predicting spontaneous preterm birth. Between 15 and 20 weeks' gestation a cervical length cutoff value of < or =2.0 cm had specificities of 97%, 98%, 99%, and 100% and negative predictive values of 99%, 98%, 95%, and 89% for delivery at <28, <30, <32, and <34 weeks' gestation, respectively. The positive predictive values for delivery at <32 and <34 weeks' gestation were 80% and 100%, respectively. Between 21 and 24 weeks' gestation a cervical length of < or =2.0 cm had specificities of 84%, 84%, 85%, and 86% and negative predictive values of 99%, 99%, 94%, and 87% for delivery at <28, <30, <32, and <34 weeks' gestation, respectively. Between 25 and 28 weeks' gestation cervical length had excellent negative predictive values of 99%, 98%, 95%, and 93% for delivery at <28, <30, <32, and <34 weeks' gestation, respectively. CONCLUSIONS: In twin gestations a cervical length of < or =2.0 cm measured between 15 and 28 weeks' gestation was at least as good as other ultrasonographic cervical parameters at predicting spontaneous preterm birth. The high specificities indicate that cervical length was better at predicting the absence than the presence of various degrees of spontaneous prematurity.

Use of cervical ultrasonography in prediction of spontaneous preterm birth in triplet gestations.

OBJECTIVE: The aim of this study was to assess the role of cervical ultrasonography in the prediction of spontaneous preterm birth in triplet gestations and to compare various ultrasonographic cervical parameters with respect to predictive ability. STUDY DESIGN: This prospective cohort study included 51 triplet gestations longitudinally evaluated between 15 and 28 weeks' gestation on 274 occasions with transvaginal cervical ultrasonography and transfundal pressure. The cervical parameters obtained were funnel width and length, cervical length, percentage of funneling, and cervical index. RESULTS: Receiver operating characteristic curve analyses showed that cervical lengths of < or =2.5 cm and < or =2.0 cm between 15 and 24 weeks' gestation and between 25 and 28 weeks' gestation, respectively, were at least as good as other ultrasonographic cervical parameters for the prediction of spontaneous preterm birth. A cervical length of < or =2.5 cm between 15 and 20 weeks' gestation had both a specificity and a positive predictive value of 100% for delivery at <28 weeks' gestation, and the sensitivities and negative predictive values ranged from 25% to 50% and from 72% to 91%, respectively, for deliveries at <28, <30, and <32 weeks' gestation. A cervical length of < or =2.5 cm between 21 and 24 weeks' gestation had an 86% sensitivity for prediction of spontaneous delivery at <28 weeks' gestation. A cervical length of < or =2.0 cm between 25 and 28 weeks' gestation had both a sensitivity and a negative predictive value of 100% for delivery at both <28 and <30 weeks' gestation. CONCLUSIONS: In triplet gestations cervical lengths of < or =2.5 cm between 15 and 24 weeks' gestation and < or =2.0 cm between 25 and 28 weeks' gestation were at least as good as other ultrasonographic cervical parameters for the prediction of spontaneous preterm birth.

Continuous ethanol production from pineapple cannery waste using immobilized yeast cells.

The cells of Saccharomyces cerevisiae ATCC 24553, were immobilized in k-carrageenan and packed in a tapered glass column reactor for ethanol production from pineapple cannery waste at temperature 30 degrees C and pH 4.5. The maximum productivity was 42.8 g ethanol 1(-1) h(-1) at a dilution rate of 1.5 h(-1). The volumetric ethanol productivity of the immobilized cells was ca. 11.5 times higher than the free cells. The immobilized cell reactor was operated over a period of 87 days at a dilution rate of 1.0 h(-1), without any loss in the immobilized cell activity. The maximum specific ethanol productivity and specific sugar uptake rate of the immobilized cells were 1.2 g ethanol g(-1) dry wt. cell h(-1) and 2.6 g sugar g(-1) dry wt. cell h(-1), respectively, at a dilution rate of 1.5 h(-1).

Agar immobilized yeast cells in tubular reactor for ethanol production.

Saccharomyces cerevisiae cells were immobilized in agar gel and used in a tubular reactor for conversion of cane molasses to ethanol at 30 degrees C, pH 4.5. Reactor was used in a continuous operation to test the operational stability and ethanol productivity. After 100 days of continuous fermentation at a dilution rate of 0.67 hr-1, some deactivation of cells was observed, but ethanol productivity was recovered by reactivating the cells by sparging air intermittently. It was found that intermittent reactivation during continuous operation was very important for satisfactory performance of the reactor. During operation, gel beads maintained their rigidity. Maximum ethanol concentration (94.9 g/L) was obtained with a feed containing 255 g/L reducing sugar, at a dilution rate of 0.2 hr-1. Maximum volumetric productivity (79.5 g ethanol /L/hr), specific ethanol productivity (0.58 g ethanol/g cells/hr), specific sugar uptake rate (1.12 g sugar/g cells/hr) and ethanol yield coefficient (0.43 g ethanol/g sugar) were obtained with a feed containing 195 g/L reducing sugar at a dilution rate of 1.33 hr-1.

Therapeutic value of bovine saliva in wound healing: a histomorphological study.

Biopsies were collected from the control (normal saline solution treated) and saliva treated wounds (back and loin region) of calves on 3rd, 7th, 14th, 21st and 28th days post-wounding. A faster connective tissue and epidermal regeneration was observed in saliva treated group. The inflammatory response was subdued as early as on 3rd day. On the 14th day the test wounds were covered with a dense layer of fibroblast and collagen and epidermal growth started. On 21st day the condensation of collagen and vascularization of the scar tissue was further augmented. By 28th day, the wounds were completely filled and nearly 85% of the wound surface was covered with epidermis.

Does oxybutynin add to the effectiveness of prompted voiding for urinary incontinence among nursing home residents? A placebo-controlled trial.

OBJECTIVE: To determine if oxybutynin, a bladder relaxant medication, adds to the effectiveness of prompted voiding (PV) in the management of urinary incontinence among nursing home residents. DESIGN: Randomized, placebo-controlled, double-blinded, dose-adjusted, crossover trial of oxybutynin added along with PV. SETTING: Seven nursing homes in Los Angeles County, California. PARTICIPANTS: Seventy-five nursing home residents with predominantly urge incontinence, whose incontinence did not respond well to a trial of PV. MAIN OUTCOME MEASURES: The frequency of incontinence, measured as the percentage of hourly (7 AM to 7 PM) physical checks over a 3-day period at which the resident was found wet. RESULTS: Sixty-three (84%) of the residents completed the study. Among those completing the trial, the percent of checks wet went from 26.5% to 23.7% on placebo to 20.2% on active drug. These changes were statistically significant but not clinically meaningful. A clinically significant decrease in the frequency of incontinence, which we defined as a relative reduction in the percent of checks wet of > 33%, occurred in 20 subjects (32%) while on active drug and in 12 subjects (19%) while on placebo (P = .48 by chi-square). Twenty-five subjects (40%) met our "continence criteria" of an average of one or less wet per day while on active drug, and 11 subjects (18%) achieved this goal on placebo (P = .005 by chi-square). CONCLUSION: Oxybutynin does not add to the clinical effectiveness of PV in the majority of nursing home residents with urge type urinary incontinence. Selected residents may, however, become more responsive to PV while on oxybutynin. Our data are consistent with other studies of bladder relaxant medications in functionally impaired populations. New drugs and/or other interventions are needed for the large number of incontinent nursing home residents who do not respond well to PV.

Predictors of successful prompted voiding among incontinent nursing home residents.

OBJECTIVE: To develop a simple, noninvasive assessment strategy that will enable nursing home staff to identify incontinent residents who respond well to prompted voiding. DESIGN: Incontinent nursing home residents underwent an extensive clinical and functional assessment and then 7 days of prompted voiding. Data from the assessment and the first 3 days of prompted voiding were used to predict responsiveness to the intervention. SETTING: Seven nursing homes. PATIENTS: A cohort of 191 incontinent, long-stay nursing home residents who passed a simple behavioral screen (able to state their name or reliably point to one of two named objects). INTERVENTION: Prompted voiding was carried out by trained research nurse's aides from 7 AM to 7 PM for 7 days. The intervention was maintained in responsive residents 5 days per week for an additional 9 weeks. MAIN OUTCOME MEASURES: Physical checks for wetness were done by research staff hourly from 7 AM to 7 PM for 3 days in a baseline condition, during days 5 through 7 of the 7-day prompted voiding intervention, and for 3 days at the end of 9 weeks of prompted voiding in the responsive group. Outcome measures were percentage of checks wet and response to prompted voiding, with "responders" defined as residents with an average of one or fewer wet episode per day on days 5 through 7 of prompted voiding. RESULTS: Seventy-eight (41%) of the residents were responders. Their wet percentage went from 26.7% to 6.4% at the end of 1 week and was maintained at 9.6% after 9 weeks of prompted voiding. The best predictors of responsiveness were the wet percentage and the appropriate toileting percentage during the first 3 days of prompted voiding, the self-care subscale score of the Multidimensional Observational Scale for the Elderly, and the ability to ambulate without human assistance. The best sensitivity and specificity in identifying responders was achieved when either the wet percentage was lower than 20% or the appropriate toileting percentage was higher than 66% during the first 3 days of prompted voiding (sensitivity, 87%; specificity, 69%). Those residents falsely identified as responders by these criteria still had a 46% relative reduction in wetness. CONCLUSIONS: A substantial proportion of nursing home residents respond well to prompted voiding. The most responsive residents can be easily identified using data collected during a 3-day trial of the intervention. The assessment strategy is consistent with federal guidelines and could be used to facilitate quality control by assessing changes in percentage of wetness from the expected norm.

Does eradicating bacteriuria affect the severity of chronic urinary incontinence in nursing home residents?

OBJECTIVE: To determine the effects of eradicating otherwise asymptomatic bacteriuria on the severity of chronic urinary incontinence among nursing home residents. DESIGN: Residents were categorized as nonbacteriuric or bacteriuric on the basis of urine cultures. Bacteriuric residents were then randomly assigned to immediate and delayed treatment groups. The delayed treatment group was included to control for spontaneous changes in the severity of incontinence. The immediate treatment group received antimicrobial therapy for 7 days; after outcome measures had been repeated, the delayed treatment group was treated. SETTING: 6 community-based nursing homes. PATIENTS: Nursing home residents with chronic urinary incontinence. MEASUREMENTS: The frequency and volume of urinary incontinence were determined by physical checks for wetness by trained research aides hourly between 7 a.m. and 7 p.m. for 3 days in all patient groups (non-bacteriuric, bacteriuric with immediate treatment, and bacteriuric with delayed treatment) at baseline, after the immediate treatment group was treated, and again after the delayed treatment group was treated. RESULTS: 191 residents were enrolled, and 176 completed the study. Bacteriuria was eradicated by antimicrobial therapy in 71 residents (40%), and 17 residents (10%) had bacteriuria before and after therapy. The percentage of hourly checks at which the residents were found wet and other measures of incontinence severity remained essentially the same after bacteriuria was eradicated. In the nonbacteriuric group, the percentage of checks that were wet increased from 29% (95% CI, 26% to 32%) at baseline to 30% (CI, 27% to 34%) on repeated measurement. In the bacteriuric groups, the percentage increased from 34% (CI, 30% to 38%) before treatment to 35% (CI, 31% to 39%) after bacteriuria was eradicated. The presence of pyuria did not affect the results. CONCLUSION: Eradicating bacteriuria has no short-term effects on the severity of chronic urinary incontinence among nursing home residents. Our data support the practice of not treating asymptomatic bacteriuria in this population and validate the recommendations in the Health Care Financing Administration's Resident Assessment Protocol for urinary incontinence.

Use of a portable ultrasound device to measure post-void residual volume among incontinent nursing home residents.

OBJECTIVE: To determine the accuracy of a portable ultrasound device for the assessment of post-void residual (PVR) volume among incontinent nursing home (NH) residents. DESIGN: Prospective, clinical series. SETTING: Seven community-based nursing homes. STUDY POPULATION: Two hundred one consecutively assessed incontinent NH residents who were participating in a larger clinical trial. MEASUREMENTS: PVR volumes measured by trained research associates using a portable ultrasound device and by in-and-out catheterization were compared. The accuracy of the ultrasound was calculated using the volume obtained by catheterization as the gold standard. RESULTS: The ultrasound demonstrated excellent test-retest and interrater reliability. For low PVRs, the device was highly sensitive (.90) for PVR < 50 mL and .95 for PVR < 100 mL) and moderately specific (.71 for PVR < 50 mL and .63 for PVR < 100 mL). For PVRs of more than 200 mL (n = 26), the ultrasound had a sensitivity of .69 and a specificity of .99. CONCLUSION: The portable ultrasound we used was reliable and reasonably accurate for assessing PVR in a representative sample of incontinent NH residents. Because the sensitivity for clinically significant urinary retention (PVR > 200 mL) was only .69, repeated measurements may be necessary to exclude high PVR in individual NH residents. Recent changes in ultrasound design should improve its ease of use and accuracy. Although measuring PVR by ultrasound is much easier and more comfortable than catheterization for both NH residents and staff, the cost of the device may be a barrier to its widespread use in the NH setting.

Studies on intravenous regional analgesia of the hind limb in the bovine.

Twenty-five buffalo calves (age: 14 +/- 1.9 months; body weight: 102 +/- 9.4 kg) were subjected to intravenous regional analgesia (IRA) of the hind limb with 2% lignocaine HCl (4 mg/kg b.w.), infused through the dorsal digital vein. In control animals 15 ml of normal saline was infused. The effect of tourniquet release after 35 (8 calves) and 65 min (7 calves) on EEG, ECG, arterial and venous pressures, blood gases and pH, respiration and temperature were studied. A detectable concentration of lignocaine occurred before the release of tourniquet. The lignocaine concentration recorded in the systemic circulation did not produce any significant nervous or cardiovascular changes before or after release of tourniquet. Transient EEG and ECG changes were seen in six (tourniquet release after 35 min) and three (tourniquet release after 65 min) IRA animals, respectively. No significant changes were seen in heart rate, respiratory rate and rectal temperature, systolic, diastolic, mean arterial and central venous pressures. Arterial blood pH, PCO2 and HCO3- concentration showed no significant differences. Animals receiving IRA did not show hypoxaemia typical to postural changes.

Haemodynamic and blood gas changes in buffaloes (Bubalus bubalis) in the supine position following thiopentone anaesthesia with premedication.

Studies were undertaken on seven adult female buffaloes (Bubalus bubalis) premedicated with triflupromazine hydrochloride (0.3 mg/kg) and chloral hydrate (30 mg/kg). Anaesthesia was induced with thiopentone sodium (10 mg/kg) and animals were kept under intermittent positive pressure ventilation. Measurements were made for 30 min in the lateral position, for 20 min in the supine position and subsequently for 40 min again in the lateral position. Regurgitation during anaesthesia was avoided by evacuation of the rumen by rumenotomy two days prior to the experiment. When animals were in the lateral position there were minimal changes in arterial pressure and heart rate but central venous pressure rose. These changes were related to intermittent positive pressure ventilation. In the supine position, increase in heart rate (28%) was associated with profound hypotension (56%) and decrease in central venous pressure (171%) in these animals. There was a fall in venous oxygen tension and a marked increase (91%) in oxygen extraction ratio. Restoration to the lateral position ameliorated all these changes rapidly. It was suggested that a 'low pressure-low flow' circulatory state exists in anaesthetised adult buffaloes in the supine position.

Isolation and Screening of Yeasts That Ferment d-Xylose Directly to Ethanol.

Natural habitats of yeasts were examined for the presence of strains able to produce ethanol from d-xylose. Black knots, insect frass, and tree exudates were screened by enrichment in liquid d-xylose-yeast extract medium. These and each d-xylose-assimilating yeast in a collection from cactus fruits and Drosophila spp. were tested for alcohol production from this sugar. Among the 412 isolates examined, 36 produced more than 1 g of ethanol liter from 20 g of d-xylose liter, all under aerated conditions. Closer examination of the strains indicated that their time courses of d-xylose fermentation followed different patterns. Some strains produced more biomass than ethanol, and among these, ethanol may or may not be assimilated rapidly after depletion of d-xylose. Others produced more ethanol than biomass, but all catabolized ethanol after carbohydrate exhaustion. Ethanol production appeared best at low pH values and under mild aeration. Possible correlations between the nutritional profiles of the yeasts and their ability to produce ethanol from d-xylose were explored by multivariate analysis. d-Xylose appeared slightly better utilized by yeasts which rate poorly in terms of fermentation. The fermentation of d-glucose had no bearing on d-xylose fermentation. No specific nutritional trait could discriminate well between better d-xylose fermentors and other yeasts.

Aerobic Fermentation of D-Xylose to Ethanol by Clavispora sp.

Eleven strains of an undescribed species of Clavispora fermented D-xylose directly to ethanol under aerobic conditions. Strain UWO(PS)83-877-1 was grown in a medium containing 2% D-xylose and 0.5% yeast extract, and the following results were obtained: ethanol yield coefficient (ethanol/D-xylose), 0.29 g g (57.4% of theoretical); cell yield coefficient (dry biomass/D-xylose), 0.25 g g; maximum ethanol concentration, 5.9 g liter; maximum volumetric ethanol productivity, 0.11 g liter h. With initial D-xylose concentrations of 40, 60, and 80 g liter, maximum ethanol concentrations of 8.8, 10.9, and 9.8 g liter were obtained, respectively (57.2, 57.1, and 48.3% of theoretical). Ethanol was found to inhibit the fermentation of D-xylose (K(p) = 0.58 g liter) more than the fermentation of glucose (K(p) = 6.5 g liter). The performance of this yeast compared favorably with that reported for some other D-xylose-fermenting yeasts.