1232 Trust-Wide Assessment of Delirium in Post-Operative Elective Surgery

Aim

Delirium is an acute change in cognition and associated with adverse patient outcomes. The incidence of post-operative delirium after elective non-cardiac surgery is unknown. We aimed to assess the incidence of post-operative delirium in this group and the effect on patient outcomes.

Method

Patients aged 65 and over who underwent elective non-cardiac surgery were identified on post-operative day three. Delirium screening was performed in real time using the validated 4-AT assessment tool. A retrospective review of the patients’ preoperative and perioperative record was conducted to collect demographics and identify risk factors for delirium. Outcome data was collected at 30 days. Patients with a positive delirium score (>4) underwent a more in-depth assessment and managing teams given a delirium management pack.

Results

75 (39 male) consecutive patients were screened over a period of 4 months. Median age 77 years and 18% had frailty assessed as “vulnerable”. The majority of patients (37.3%) underwent thoracic surgery, followed by hepatobiliary (17.3%), gynaecological (17.3%), colorectal (12%), maxillofacial (9.3%) and ENT (4%). 5.3% (4) of patients had a positive 4-AT screen. No patients had a formal delirium screen or diagnosis in the initial 48 hours. The median length of stay for patients with a positive screen was 8.5 days (IQR 7.5-12) compared to 8 days (IQR 5-13) for patients with a negative screen.

Conclusions

Reassuringly, rate of post-operative delirium following elective operations in our Trust are low (5%). Larger numbers of patients are required to assess the impact this has on patient outcomes and identify correlation with risk factors.

Association of hyperglycaemia with hospital mortality in nondiabetic COVID-19 patients: A cohort study

Objective

Diabetes is a known risk factor for mortality in Coronavirus disease 2019 (COVID-19) patients. Our objective was to identify prevalence of hyperglycaemia in COVID-19 patients with and without prior diabetes and quantify its association with COVID-19 disease course.

Research design and methods

This observational cohort study included all consecutive COVID-19 patients admitted to John H Stroger Jr. Hospital, Chicago, IL from March 15, 2020 to May 3, 2020 and followed till May 15, 2020. The primary outcome was hospital mortality, and the studied predictor was hyperglycaemia [any blood glucose ≥7.78 mmol/L (140 mg/dL) during hospitalization].

Results

Of the 403 COVID-19 patients studied, 51 (12.7%) died; 335 (83.1%) were discharged while 17 (4%) were still in hospital. Hyperglycaemia occurred in 228 (56.6%) patients; 83 of these hyperglycaemic patients (36.4%) had no prior history of diabetes. Compared to the reference group no-diabetes/no-hyperglycaemia patients the no-diabetes/hyperglycaemia patients showed higher mortality [1.8% versus 20.5%, adjusted odds ratio 21.94 (95% confidence interval 4.04–119.0), P < 0.001]; improved prediction of death (P = 0.01) and faster progression to death (P < 0.01). Hyperglycaemia within the first 24 and 48 h was also significantly associated with mortality (odds ratio 2.15 and 3.31, respectively).

Conclusions

Hyperglycaemia without prior diabetes was common (20.6% of hospitalized COVID-19 patients) and was associated with an increased risk of and faster progression to death. Development of hyperglycaemia in COVID-19 patients who do not have diabetes is an early indicator of progressive disease.

Combining Diffusion Tensor Metrics and DSC Perfusion Imaging: Can It Improve the Diagnostic Accuracy in Differentiating Tumefactive Demyelination from High-Grade Glioma?

BACKGROUND AND PURPOSE

Tumefactive demyelinating lesions with atypical features can mimic high-grade gliomas on conventional imaging sequences. The aim of this study was to assess the role of conventional imaging, DTI metrics (p:q tensor decomposition), and DSC perfusion in differentiating tumefactive demyelinating lesions and high-grade gliomas.

MATERIALS AND METHODS

Fourteen patients with tumefactive demyelinating lesions and 21 patients with high-grade gliomas underwent brain MR imaging with conventional, DTI, and DSC perfusion imaging. Imaging sequences were assessed for differentiation of the lesions. DTI metrics in the enhancing areas and perilesional hyperintensity were obtained by ROI analysis, and the relative CBV values in enhancing areas were calculated on DSC perfusion imaging.

RESULTS

Conventional imaging sequences had a sensitivity of 80.9% and specificity of 57.1% in differentiating high-grade gliomas (P = .049) from tumefactive demyelinating lesions. DTI metrics (p:q tensor decomposition) and DSC perfusion demonstrated a statistically significant difference in the mean values of ADC, the isotropic component of the diffusion tensor, the anisotropic component of the diffusion tensor, the total magnitude of the diffusion tensor, and rCBV among enhancing portions in tumefactive demyelinating lesions and high-grade gliomas (P ≤ .02), with the highest specificity for ADC, the anisotropic component of the diffusion tensor, and relative CBV (92.9%). Mean fractional anisotropy values showed no significant statistical difference between tumefactive demyelinating lesions and high-grade gliomas. The combination of DTI and DSC parameters improved the diagnostic accuracy (area under the curve = 0.901). Addition of a heterogeneous enhancement pattern to DTI and DSC parameters improved it further (area under the curve = 0.966). The sensitivity increased from 71.4% to 85.7% after the addition of the enhancement pattern.

CONCLUSIONS

DTI and DSC perfusion add profoundly to conventional imaging in differentiating tumefactive demyelinating lesions and high-grade gliomas. The combination of DTI metrics and DSC perfusion markedly improved diagnostic accuracy.

Outcome of Surgical Treatment in Medically Refractory Epilepsy

The aim of epilepsy surgery is not only to control seizures but also to curtail future adverse neurological sequelae and improve quality of life. Epilepsy surgery is a viable treatment option for selected cases of medically refractory epilepsy. A study was carried out with a series of 34 cases who underwent epilepsy surgery at Sree Chitra Tirunal Institute for Medical Science & Technology, Kerala, India during July, 2010 to December, 2010. Clinical features, operative procedures and early response to treatment were cha'racterized. Among 34 cases, main clinical manifestation was recurrent seizures. All cases were evaluated by Video Electro Encephalogram (EEG) & Magnetic Resonance Imaging (MRI) of brain with epilepsy protocol. Nearly 58% cases were diagnosed as mesial temporal sclerosis who were treated by anterior temporal lobectomy (ATL) with amygdalohippocampectomy (AH). Excision of epileptogenic foci was confirmed by preoperative Electro Cardiogram. Early response to surgery was good. However, a prolonged longitudinal follow up is essential for accurate assessment of seizure outcome.

Deposition of the spermatozoon in the human oocyte at ICSI: impact on oocyte survival, fertilization and blastocyst formation

PURPOSE

To evaluate whether the deposition of the spermatozoon in the human oocyte at ICSI has any effect on oocyte survival, fertilization, blastocyst development and quality.

METHODS

In a prospective study, including 78 ICSI cycles, sibling oocytes were injected with "no intention" (group A, standard ICSI, n = 393) or "intention" to deposit the spermatozoon under the cortex (group B, n = 354). Outcome parameters were oocyte survival and fertilization, as well as blastocyst formation and quality.

RESULTS

Depositing the sperm under the cortex of the oocyte was not always successful for its final position, therefore, group B was divided into three subgroups: B1 successful deposition (119 oocytes, 33.6 % of oocytes in group B); B2 initially successful but spermatozoon spontaneously relocated after 2 min (136 oocytes, 38.4 %); and B3 unsuccessful deposition (99 oocytes, 28.0 %). Group A and B were compared on an intention-to-treat basis. Additionally, A, B1, B2 and B3 were also compared. The oocyte survival and fertilization, blastocyst and top-quality blastocyst developmental rates were not significantly different.

CONCLUSIONS

The procedure of depositing the spermatozoon intentionally under the oocyte cortex demanded high technical skills. Successful positioning was only obtained in 34 % of the attempts. We obtained no evidence of improved oocyte survival and fertilization, blastocyst formation and quality when the spermatozoon was permanently positioned under the oocyte cortex. Taken together, depositing the spermatozoon under the oocyte cortex is not recommended for routine ICSI application.

Gastrointestinal ultrasonography of normal Standardbred neonates and frequency of asymptomatic intussusceptions

Background

Ultrasonographic appearance of the gastrointestinal (GI) tract of equine neonates has not been completely described.

Objectives

To describe (1) sonographic characteristics of the GI segments in normal nonsedated equine neonates, (2) intra‐ and interobserver variation in wall thickness, and (3) the sonographic appearance of asymptomatic intussusceptions, and (4) to compare age and sonographic findings of foals with and without asymptomatic intussusceptions.

Animals

Eighteen healthy Standardbred foals ≤5 days of age.

Methods

Prospective, cross‐sectional blinded study. Gastrointestinal sonograms were performed stall‐side. Intraobserver variability in wall thickness measurements was determined by calculating the coefficient of variation (CV). The Bland–Altman method was used to assess interobserver bias. Student's t‐test and Fisher's exact test were used to test the association among presence of intussusceptions, age, and selected sonographic findings.

Results

The reference ranges (95% predictive interval) for wall thickness were 1.6–3.6 mm for the stomach, 1.9–3.2 mm for the duodenum, 1.9–3.1 mm for the jejunum, 1.3–2.2 mm for the colon, and 0.8–2.7 mm for the cecum. Intraobserver wall thickness CV ranged from 8 to 21% for the 2 observers for 5 gastrointestinal segments. The interobserver bias for wall thickness measurements was not significant except for the stomach (0.14 mm, P < .05) and duodenum (0.29 mm, P < .05). Diagnostic images of mural blood flow could not be obtained. Asymptomatic intussusceptions were found in 10/18 neonates. Associations between sonographic variables or age and the presence of intussusceptions were not found.

Conclusions and Clinical Importance

Sonographic characteristics of the GI tract of normal Standardbred neonates can be useful in evaluating ill foals. Asymptomatic small intestinal intussusceptions occur in normal Standardbred neonates.

Blackhead disease: reduced sensitivity of Histomonas meleagridis to nitarsone in vitro and in vivo

Histomonas meleagridis, a flagellated protozoan parasite, is the causative agent of blackhead disease or histomoniasis in gallinaceous birds. Currently nitarsone (4-nitrophenylarsonic acid) is the only approved preventative drug available in the United States against blackhead disease. Initially we tested the sensitivity of three different isolates of H. meleagridis collected from outbreaks in North Carolina (strain MNC), Michigan (strain ZM), and Georgia (strain BG) to nitarsone using in vitro culture conditions. Strain ZM and strain BG at 100 and 400 ppm showed reduced growth in comparison to their respective control groups. However, there was no inhibition of growth in strain MNC treated with nitarsone at 100 ppm, while reduced growth was seen at 400 ppm. To test the resistance of strain MNC to nitarsone in vivo, turkey poults fed a nitarsone or a control diet were inoculated cloacally with H. meleagridis. The nitarsone-treated group of birds did not show any significant difference compared to that of infected control group when measuring weight gain and liver and cecal lesions scores. Histomonas meleagridis were reisolated from the nitarsone-fed turkeys and subjected to the in vitro assay. Regenerated H. meleagridis maintain their resistance to nitarsone at 100 ppm. This study demonstrates that strain MNC has acquired partial resistance to nitarsone.

Long-term effects of continuing adjuvant tamoxifen to 10 years versus stopping at 5 years after diagnosis of oestrogen receptor-positive breast cancer: ATLAS, a randomised trial

BACKGROUND

For women with oestrogen receptor (ER)-positive early breast cancer, treatment with tamoxifen for 5 years substantially reduces the breast cancer mortality rate throughout the first 15 years after diagnosis. We aimed to assess the further effects of continuing tamoxifen to 10 years instead of stopping at 5 years.

METHODS

In the worldwide Adjuvant Tamoxifen: Longer Against Shorter (ATLAS) trial, 12,894 women with early breast cancer who had completed 5 years of treatment with tamoxifen were randomly allocated to continue tamoxifen to 10 years or stop at 5 years (open control). Allocation (1:1) was by central computer, using minimisation. After entry (between 1996 and 2005), yearly follow-up forms recorded any recurrence, second cancer, hospital admission, or death. We report effects on breast cancer outcomes among the 6846 women with ER-positive disease, and side-effects among all women (with positive, negative, or unknown ER status). Long-term follow-up still continues. This study is registered, number ISRCTN19652633.

FINDINGS

Among women with ER-positive disease, allocation to continue tamoxifen reduced the risk of breast cancer recurrence (617 recurrences in 3428 women allocated to continue vs 711 in 3418 controls, p=0·002), reduced breast cancer mortality (331 deaths vs 397 deaths, p=0·01), and reduced overall mortality (639 deaths vs 722 deaths, p=0·01). The reductions in adverse breast cancer outcomes appeared to be less extreme before than after year 10 (recurrence rate ratio [RR] 0·90 [95% CI 0·79–1·02] during years 5–9 and 0·75 [0·62–0·90] in later years; breast cancer mortality RR 0·97 [0·79–1·18] during years 5–9 and 0·71 [0·58–0·88] in later years). The cumulative risk of recurrence during years 5–14 was 21·4% for women allocated to continue versus 25·1% for controls; breast cancer mortality during years 5–14 was 12·2% for women allocated to continue versus 15·0% for controls (absolute mortality reduction 2·8%). Treatment allocation seemed to have no effect on breast cancer outcome among 1248 women with ER-negative disease, and an intermediate effect among 4800 women with unknown ER status. Among all 12,894 women, mortality without recurrence from causes other than breast cancer was little affected (691 deaths without recurrence in 6454 women allocated to continue versus 679 deaths in 6440 controls; RR 0·99 [0·89–1·10]; p=0·84). For the incidence (hospitalisation or death) rates of specific diseases, RRs were as follows: pulmonary embolus 1·87 (95% CI 1·13–3·07, p=0·01 [including 0·2% mortality in both treatment groups]), stroke 1·06 (0·83–1·36), ischaemic heart disease 0·76 (0·60–0·95, p=0·02), and endometrial cancer 1·74 (1·30–2·34, p=0·0002). The cumulative risk of endometrial cancer during years 5–14 was 3·1% (mortality 0·4%) for women allocated to continue versus 1·6% (mortality 0·2%) for controls (absolute mortality increase 0·2%).

INTERPRETATION

For women with ER-positive disease, continuing tamoxifen to 10 years rather than stopping at 5 years produces a further reduction in recurrence and mortality, particularly after year 10. These results, taken together with results from previous trials of 5 years of tamoxifen treatment versus none, suggest that 10 years of tamoxifen treatment can approximately halve breast cancer mortality during the second decade after diagnosis.

FUNDING

Cancer Research UK, UK Medical Research Council, AstraZeneca UK, US Army, EU-Biomed.

An outbreak of blackhead disease (Histomonas meleagridis) in farm-reared bobwhite quail (Colinus virginianus)

An outbreak of blackhead disease (Histomonas meleagridis) in farm-reared flock of 13,500 bobwhite quail (Colinus virginianus) resulted in mortality totaling approximately 1500 in 4 wk. Necropsy of 56 dead birds at midoutbreak (from a total that day of 131) revealed that 55 had severe cecal lesions typical of blackhead, and only 3 had visible lesions in the liver. Necropsy of apparently healthy birds failed to detect any signs of infection. Presence of H. meleagridis in affected ceca was proved by culture in vitro and PCR tests.

Validation of the Arabic version of the early inflammatory arthritis detection tool

OBJECTIVE

To evaluate the reliability and validity of the Arabic version of the Early Inflammatory Arthritis Questionnaire (EIAQ-A), a detection tool for screening for early inflammatory arthritis (EIA) in Arabic-speaking populations.

SUBJECTS AND METHODS

A cross-sectional study was conducted among 30 consecutive participants (21 female and 9 male) attending the Internal Medicine Outpatient Clinic at Mubarak Al-Kabeer Hospital. They completed the self-administered EIAQ-A twice within a 2-week period. Their disease activity was evaluated during the visits based on clinical and laboratory variables. Cross-cultural adaptation was performed using forward and backward translations of the original questionnaire. Test-retest reliability of the EIAQ-A was evaluated using the measure of agreement, kappa (κ), between the response of participants in the two interviews. Internal consistency of the EIAQ-A was measured using the Kudar-Richardson-20 coefficient (KR-20), a binary response equivalent to Cronbach's α. External construct validity was assessed by Spearman's rank correlation coefficient (rs) between the score of EIAQ-A and both clinical and laboratory variables of disease activity.

RESULTS

The test-retest reliability for EIAQ-A was good (κ = 0.558) for the overall score and between 0.841 and 0.368 for the subscale scores. Internal consistency had an acceptable value of KR-20 = 0.869. The construct validity for EIAQ-A was high for all disease activity variables tested, rs was between 0.727 (swollen joint count) and 0.896 (visual analog scale pain score).

CONCLUSION

The EIAQ-A was a reliable and valid tool for population screening for EIA. Its use may accelerate the early detection of EIA in Arabic-speaking communities.

Back to basics: ankle reflex in the evaluation of peripheral neuropathy in type 2 diabetes mellitus

BACKGROUND

Ankle reflex is a simple screening tool frequently used in the detection of peripheral neuropathy.

AIM

The purpose of this study is to assess the performance characteristics of ankle reflex in detecting diabetic peripheral neuropathy (DPN) by evaluating the sensitivity, specificity and the predictive ability of the ankle reflex, a component of Neuropathy Disability Score (NDS) with reference to Nerve Conduction Studies (NCS).

METHODS

A total of 151 patients with type 2 diabetes were assessed (47 males, 104 females). Grading of neuropathy was done using Neuropathy Symptom Score (NSS), NDS and NCS. Patients were divided into two groups, those with abnormal NCS (Group 1) and those with normal NCS (Group 2). Demographic characteristics, biochemistry, NSS and NDS were assessed between the two groups. Taking NCS as the gold standard, sensitivity, specificity and predictive ability of the ankle reflex were calculated and compared with other tests included in NDS, namely vibration sense, superficial pain and temperature sensation.

RESULTS

There were 59 (39.1%) patients in Group 1 and 92 (60.9%) in Group 2. NSS and NDS demonstrated strong positive association with NCS. Taking NCS as the gold standard, ankle reflex yielded the highest sensitivity and specificity (91.5 and 67.4%, respectively), closely followed by that of vibration sense.

CONCLUSION

Ankle reflex is a powerful screening tool with high sensitivity and negative predictive value, but a combination of ankle reflex and vibration sense has superior sensitivity and specificity compared with either of them done alone for the detection of DPN in clinical settings.

[Kikuchi disease and lupus: case report, literature review and FDG PET/CT interest]

Kikuchi disease is a rare entity characterized by lymphadenopathy and fever. Pathology study of lymph node biopsies provides the diagnosis. The disease course is favorable. The disease can occur isolated, or associated with other pathologies including lupus or mixed connective tissue disease. We report a case of Kikuchi disease in a 35-year-old woman, occurring 12 years after the diagnosis of overlap syndrome with antiphospholipid antibodies. The patient was given prednisone 25mg per day and long-term hydroxychloroquine. FDG PET/CT showed FDG-avidity nodular masses. After bolus corticosteroid therapy, outcome was favorable with disappearance of metabolic hyperactivity on the FDG PET/CT. The bolus prednisone treatment could then be discontinued. In the 61 cases of Kikuchi disease and lupus associations previously published, Kikuchi disease was diagnosed after lupus in only 13 % of the observations. In these cases, use of FDG PET/ CT was not reported. For us, FDG PET/CT was useful for diagnosis, for choosing the biopsy site and for follow-up.

Cellular responses in the skin of the gilthead sea bream Sparus aurata L. and the sea bass Dicentrarchus labrax (L.) exposed to high ammonia

Adult gilthead sea bream Sparus aurata and sea bass Dicentrarchus labrax were exposed for 24 and 48 h, respectively, to two concentrations of ammonia each (mean values of 3·34 and 13·10 mg l(-1) TA-N in S. aurata; 2·99 and 11·90 mg l(-1) TA-N in D. labrax). Light microscopy and computerized morphometry were used to evaluate ammonia-induced alterations in skin structure during exposure and following recovery in normal water. In S. aurata, ammonia exposure induced a concentration-dependent increase in the number (hyperplasia) of neutral mucous cells (mc), with peak values at 24 h recovery after exposure. An increase in the dispersion of melanosomes in skin melanocytes was also observed in the dermis and occasionally in the epidermis of S. aurata, with peak values at 24 h of ammonia exposure. Exposure of D. labrax to ammonia had, likewise, concentration-dependent effects on mucous secretion. Of the two types of mc in this species, there was an increase in the number of the neutral mc and a reduction in the much more numerous acid mc, with peak values at 24 and 48 h, respectively, of ammonia exposure. The more intense mucous secretion in D. labrax compared to S. aurata could be related to the lower tolerance to ammonia in D. labrax, as reported elsewhere. Finally, the increase in melanosome dispersion was less evident in D. labrax, due to highly variable control values. These morphological alterations to the skin could be useful indicators of non-specific stress in cultured fishes.

Multifocal desmoplastic noninfantile astrocytoma

This is a report of a case of multifocal desmoplastic astrocytoma in an 11-year-old child in which we describe the MRI findings and discuss the possible mechanism of its development. The MRI appearances in our case support the view that the tumor is primarily of leptomeningeal or superficial cortical origin, with cystic formation secondary to entrapment of cerebrospinal fluid. The question of whether or not the lesions are metastases or metachronous lesions is also discussed. Desmoplastic astrocytoma at a noninfantile age is extremely rare: only four cases have been reported in the literature so far. Even more unusual is the presence of this lesion in multiple locations at the initial presentation.

Oral Valgancyclovir Versus Intravenous Gancyclovir for Cytomegalovirus Prophylaxis in Kidney Transplant Recipients

BACKGROUND

Prophylaxis against cytomegalovirus (CMV) is a regular practice in organ transplantation. Oral valgancyclovir appears to be an interesting alternative to the usual intravenous form.

PATIENTS AND METHODS

We prospectively compared the response of intravenous gancyclovir for 2 weeks (GAN; n=41) to oral valgancyclovir for 2 weeks (VAL2w; n=23) or 3 months (VAL3m; n=46) in kidney transplant recipients receiving induction immunosuppression. CMV antigenemia assay and/or polymerase chain reaction (PCR) were used for viral detection. Patients were followed for a minimum of 6 months posttransplantation. SPSS software was used for statistical analysis using a cutoff of significance as P<.05.

RESULTS

There was no statistical difference in the demographic features among the study groups. However, human leukocyte antigen (HLA) match was better in the VAL3m group and the patients of this group received less ATG induction immunosuppression (41.3%) compared with the GAN group (100%). The incidence of acute rejection was not different among the study groups. There was a higher incidence of fever with positive CMV tests in the VAL2w group (P=.035) compared with the other groups, while leukopenia with a negative CMV test was significantly higher in the VAL3m group (P=.04). The incidence of CMV disease was higher in the VAL2w group (30.4%) compared with the GAN group (14.6%) or the VAL3m group (8.7%). Renal function was significantly worse in the VAL2w group at 3 and 6 months (P=.011 and .02, respectively).

CONCLUSIONS

Three months oral valgancyclovir prophylaxis for CMV was a more effective regimen compared with intravenous gancyclovir for 2 weeks. Shorter courses were associated with a higher incidence of CMV infection and poorer graft function. Leukopenia observed in patients receiving valgancyclovir may be a drug-related side effect.

Telovelar approach: technical issues for large fourth ventricle tumors

OBJECTS

Fourth ventricle is conventionally accessed via resection of the part of the vermis for total excision of the tumors at the expense of significant morbidity. Numerous avenues have been identified to minimize the morbidity; some of which include transforaminal, subtonsillar, telovelar approaches, etc. These approaches are devised on the basis that accurate dissection along the natural avascular planes will avoid injury to the important structures in this area minimizing morbidity. We attempt to emphasize the technique of telovelar approach and the problems encountered while employing this technique for excision of large fourth ventricle tumors.

MATERIALS AND METHODS

Fifteen patients with fourth ventricle tumors were operated during January to September 2005 at Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India. Fourteen of these cases were medulloblastomas, and one was ependymoma. All the patients were operated in prone oblique position via telovelar approach.

CONCLUSION

Clear understanding of the normal anatomy will help in meticulous dissection and will result in reduced morbidity. Significant incidence of postoperative ataxia and mutism is seen with this approach in large tumors, and this can be avoided by staged dissection of the uvulotonsillar cleft.

Influence of commercial sanitizers on lipopolysaccharide production by Salmonella Enteritidis ATCC 13076

The effect of typical sanitizers on the composition and toxicity of lipopolysaccharides (LPSs) produced by Salmonella Enteritidis ATCC 13076 was analyzed. Salmonella Enteritidis was propagated up to the late exponential phase in the presence of commercial sanitizing solutions. LPS was extracted and derivatized with trifluoroacetylation, and gas chromatography-mass spectrometry analysis and the chromogenic Limulus amoebocyte lysate assay were used to assess the ultrastructure and toxicity of the LPS. The viability and debris formation during growth were evaluated to verify the bactericidal and bacteriostatic effects of the sanitizers and to assess sanitizer effects on LPS formation. The LPSs produced were quantified at 1.7 x 10(4), 1.2 x 10(4), 3.6 x 10(3), and 9.6 x 10(4) [KDO] x OD(620nm)(-1) for the controls and the organisms grown in the presence of a chlorinated sanitizer, a heavy-duty alkaline cleaner, and a phenolic hand wash solution, respectively. In response to these treatments, the short-chain polysaccharide fractions of the LPSs in the Salmonella Enteritidis cells increased. This finding suggests that this organism increases the low-molecular-weight fraction of the LPS in relation to the high-molecular-weight fraction to survive these unfavorable conditions. The cumulative change in the LPS in response to the sanitizers influenced the toxicity of the LPS; however, this change could not be related to an individual compound within any of the assessed fractions.

Bagasse-assisted bioremediation of ammonia from shrimp farm wastewater

Development of new economically feasible ecofriendly products from agricultural wastes or byproducts for shrimp farm wastewater treatment is the objective of our continued research. Ammonia is a nitrogenous toxicant, which is commonly found in wastewater from shrimp farms. In the present study, we explored the possibility of the use of simply and inexpensively prepared bagasse products so that this abundant crop byproduct could be used to remove ammonia from shrimp farm wastewater. Bagasse, a natural highly fibrous lignocellulosic byproduct of sugarcane, was converted into five different products. Experimental results have shown that ammonia is efficiently removed from wastewater by four bagasse products with a dose of 1 to 6 g/L within 24 hours. The effect of bagasse products on other water quality parameters and growth kinetics of biofilm bacteria onto bagasse fiber have also been studied. Efficacies of products were compared by using statistical analysis. Products developed from bagasse are useful and economical.