Relative resistance of Salmonella serotypes (Typhimurium, Infantis, and Reading) to peroxyacetic acid on chicken wings.

Peroxyacetic acid (PAA) is widely used as an antimicrobial in poultry processing. Recent salmonellosis outbreaks caused by Salmonella Infantis (SI) from chicken products and Salmonella Reading (SR) from turkey products have raised concerns about their enhanced resistance (compared to Salmonella Typhimurium [ST]) to commonly used antimicrobial interventions such as PAA. The objective of this research was to evaluate the efficacy of PAA against Salmonella serotypes (Typhimurium, Infantis and Reading), effect on product color and decomposition of PAA at different pH levels. Fresh chicken wings (0.45 kg) were inoculated with a cocktail (ca. 6 log CFU/mL) of nalidixic acid resistant ST, rifampicin resistant SI and kanamycin resistant SR. Inoculated chicken wings were immersed in PAA solutions (100 or 500 ppm; adjusted to either pH 8.5 or unadjusted natural pH) for either 10 s or 60 min to replicate treatments for chicken parts or whole carcasses, respectively. Treated chicken wings were rinsed in buffered peptone water (100 mL) containing sodium thiosulfate (0.1 %), serially diluted in peptone water supplemented with 200 ppm of nalidixic acid, rifampicin or kanamycin for enumeration of ST, SI, and SR respectively, and plated on APC Petrifilm. Immersion of chicken wings in 500 ppm PAA for 60 min resulted in greater microbial reductions (P ≤ 0.05) of ST, SI, SR of ca. Two log CFU/mL each, compared to 10 s treatment. Regardless of concentration and pH of PAA, increased exposure time (60 min vs. 10 s) resulted in greater reductions (P ≤ 0.05) of ST, SI, SR. ST was slightly more resistant to PAA solutions than S. Infantis and S. Reading (P ≤ 0.05) for all experimental conditions (PAA conc, pH, and exposure times). Faster decomposition of PAA (100 and 500 ppm) was observed at pH 8.5 compared to unadjusted, natural pH (P ≤ 0.05). Product color (lightness, L*) was not affected regardless of the PAA concentration, exposure time or the pH.

Low-dose Perioperative Dexamethasone Improves 24-hour Post-Operative Pain after Anterior Cruciate Ligament Reconstruction.

Introduction: Post-operative pain following anterior cruciate ligament reconstruction remains an important challenge. Steroids are used in various surgical procedures to decrease post-operative nausea, vomiting and pain. However, only a few studies have reported the effect of systemic administration of steroids in controlling postoperative pain after anterior cruciate ligament surgery. Materials and methods: We have conducted a prospective randomised trial with 109 patients divided into two groups to determine if administration of dexamethasone in the perioperative period improves pain in the post-operative period. The patients were divided into two groups: D, treatment (dexamethasone) and P, control placebo (saline). Patients in the D treatment group were given the first dose of 10mg of intravenous dexamethasone intravenously intraoperatively and the second dose on transferring of the patient to the inpatient department. The patients in the placebo P group, were administered normal saline in the perioperative period in a similar manner. Result: Post-operative pain was significantly less in the dexamethasone group at rest and on walking (p<0.001) for the first 24 hours after surgical procedure. Subsequently, the VAS pain scores were almost similar in both groups at 48 and 72 hours. The administration of dexamethasone resulted in less requirement of antiemetic and rescue analgesia medication There was no difference in range of motion and wound complications rate during the follow-up period at six months. No adverse side effect, like osteonecrosis of the hip, was detected. Conclusion: The pain following anterior cruciate ligament reconstruction is severe during the first 24 hours and perioperative administration of dexamethasone can decrease the post-operative pain substantially.

Low-dose Perioperative Dexamethasone Improves 24-hour Post-Operative Pain after Anterior Cruciate Ligament Reconstruction

@#Introduction: Post-operative pain following anterior cruciate ligament reconstruction remains an important challenge. Steroids are used in various surgical procedures to decrease post-operative nausea, vomiting and pain. However, only a few studies have reported the effect of systemic administration of steroids in controlling postoperative pain after anterior cruciate ligament surgery. Materials and methods: We have conducted a prospective randomised trial with 109 patients divided into two groups to determine if administration of dexamethasone in the perioperative period improves pain in the post-operative period. The patients were divided into two groups: D, treatment (dexamethasone) and P, control placebo (saline). Patients in the D treatment group were given the first dose of 10mg of intravenous dexamethasone intravenously intraoperatively and the second dose on transferring of the patient to the inpatient department. The patients in the placebo P group, were administered normal saline in the perioperative period in a similar manner. Result: Post-operative pain was significantly less in the dexamethasone group at rest and on walking (p<0.001) for the first 24 hours after surgical procedure. Subsequently, the VAS pain scores were almost similar in both groups at 48 and 72 hours. The administration of dexamethasone resulted in less requirement of antiemetic and rescue analgesia medication There was no difference in range of motion and wound complications rate during the follow-up period at six months. No adverse side effect, like osteonecrosis of the hip, was detected. Conclusion: The pain following anterior cruciate ligament reconstruction is severe during the first 24 hours and perioperative administration of dexamethasone can decrease the post-operative pain substantially.

On-site generated peroxy acetic acid (PAA) technology reduces Salmonella and Campylobacter on chicken wings.

Peroxyacetic acid (PAA) is a widely used antimicrobial during poultry processing that requires to be shipped in a concentrated solution, stored under hazardous conditions and diluted for use. On-site PAA generation using nonhazardous ingredients can help eliminate transportation and storage issues at the processing plant and reduce the risk of occupational hazards. The objective of the proposed research was to 1) evaluate the efficacy of on-site generated PAA in reducing Salmonella and Campylobacter populations compared to the commercially available PAA stock solutions and 2) to perform color measurements to evaluate any deviations between treatments. PAA solutions at 50 and 100 ppm were used for treating the chicken wings. Fresh chicken wings (0.45 kg) were inoculated with a cocktail of nalidixic acid resistant Salmonella Typhimurium (STNR) and gentamicin resistant Campylobacter coli (CCGR) and immersed in PAA solutions (50 and 100 ppm) adjusted to pH 8.5 and 10.0 or 10.5, for either 10 s or 60 min. Treated chicken wings were rinsed for 1 min in chilled BPW (100 mL), serially diluted and plated on APC Petrifilm for Salmonella, spread plated on Campy-cefex agar supplemented with gentamicin (200 ppm) for Campylobacter enumeration. Immersion of chicken wings in 100 ppm PAA for 60 min irrespective of pH levels and PAA solutions resulted in greater microbial reductions (P < 0.05) of Salmonella by 1.68 and 1.42 log CFU/mL for SaniDate, 1.82 and 1.83 log CFU/mL for OxyFusion (on-site generated). For the same treatments, Campylobacter reductions of 1.59 and 1.36 log CFU/mL for SaniDate, 1.63 and 1.71 log CFU/mL for OxyFusion were achieved. The antimicrobial efficiency of PAA was not affected by pH and type of PAA solution. No significant differences (P > 0.05) in color were observed between treatments and controls. On-site generated PAA provides poultry processors an effective, safer, and less hazardous alternative to commercially available PAA solutions, ensuring poultry workers' health and safety.

The removal of acetabular bone in hip resurfacing and cementless total hip replacement: a comparison using the ratio of the size of the acetabular component to the diameter of the native femoral head.

The purpose of this study was to compare the amount of acetabular bone removed during hip resurfacing (HR) and cementless total hip replacement (THR), after controlling for the diameter of the patient's native femoral head. Based on a power analysis, 64 consecutive patients (68 hips) undergoing HR or THR were prospectively enrolled in the study. The following data were recorded intra-operatively: the diameter of the native femoral head, the largest reamer used, the final size of the acetabular component, the size of the prosthetic femoral head and whether a decision was made to increase the size of the acetabular component in order to accommodate a larger prosthetic femoral head. Results were compared using two-sided, independent samples Student's t-tests. A statistically significant difference was seen in the mean ratio of the size of the acetabular component to the diameter of the native femoral head (HR: 1.05 (SD 0.04) versus THR: 1.09 (SD 0.05); p < 0.001) and largest acetabular reamer used to the diameter of the native femoral head (HR: 1.03 (SD 0.04) versus THR: 1.09 (SD 0.05); p < 0.001). The ratios varied minimally when the groups were subdivided by gender, age and obesity. The decision to increase the size of the acetabular component to accommodate a larger femoral head occurred more often in the THR group (27% versus 9%). Despite the emphasis on avoiding damage to the femoral neck during HR, the ratio of the size of the acetabular component to the diameter of the native femoral head was larger in cementless THR than in HR.

Verification of some building materials as gamma-ray shields.

The shielding properties for gamma rays of a few low Z materials were investigated. The values of the mass attenuation coefficient, equivalent atomic number, effective atomic number, exposure buildup factor and energy absorption buildup factor were calculated and used to estimate the shielding effectiveness of the samples under investigation. It has been observed that the shielding effectiveness of a sample is directly related to its effective atomic number. The shielding character of any sample is a function of the incident photon energy. Good shielding behaviour has been verified in soil samples in the photon energy region of 0.015-0.30 MeV and of dolomite in 3-15 MeV. The results have been shown graphically with more useful conclusions.

Verification of dosimetric materials to be used as tissue-substitutes in radiological diagnosis.

Dosimetric materials have been investigated in terms of calculated mass energy absorption coefficient, equivalent atomic number and KERMA (kinetic energy released per unit mass) in the energy range 0.015-15 MeV. Using analytical methodology it has verified that nylon is the best substitute dosimetric material for skin, muscle, bone and soft-tissues. Relative energy absorption buildup factors calculated by G-P fitting method confirm the findings. Nylon has been found to be good tissue substitute material for making tissue-phantoms of the biological tissues investigated.

The fate and significance of retained staples after stapled haemorrhoidopexy.

AIM: We studied the fate of staples after stapled haemorrhoidectomy (SH) and reviewed the complications they may cause. METHOD: A survey was carried among 16 surgeons experienced at performing SH to assess their knowledge regarding retained staples. In addition, plain pelvic radiology was used to visualize residual staples at different time intervals after SH in 45 patients. RESULTS: Ten (63%) surgeons informed their patients that the staples would be shed within 3 months of SH. Regardless of the timing of surgery, part of the staple line was radiologically visible in all patients, and in 19 patients (45%) the staple line was completely visible. CONCLUSION: Contrary to the common belief, the majority of staples are retained after SH.

Alkaline stress-induced apoptosis in human pulmonary artery endothelial cells.

The effect of alkaline stress, or an increase in extracellular pH (pHext), on cell viability is poorly defined. Human pulmonary artery endothelial cells (HPAEC) were subjected to alkaline stress using different methods of increasing pHext. Viability and mode of cell death following alkaline stress were determined by assessing nuclear morphology, ultrastructural features, and caspase-3 activity. Incubation of monolayers in media set to different pHext values (7.4-8.4) for 24-h induced morphological changes suggesting apoptosis (35-45% apoptotic cells) following severe alkaline stress. The magnitude of apoptosis was related to the severity of alkaline stress. These findings were confirmed with an assessment of ultrastructural changes and caspase-3 activation. While there was no difference in the intracellular calcium level ([Ca(2+)](i)) in monolayers set to pHext 7.4 versus 8.4 following the first hour of alkaline stress, blockade of calcium uptake with the chelator, EGTA, potentiated the magnitude of apoptosis under these conditions. Potentiation of apoptosis was reduced by calcium supplementation of the media. Finally, alkaline stress was associated with an increase in intracellular pH. This is the first report of apoptosis following alkaline stress in endothelial cells in the absence of other cell death stimuli.

Enhancement of wound healing by shikonin analogue 93/637 in normal and impaired healing.

Wound healing is a complicated biological process, which involves interactions of multiple cell types, various growth factors, their mediators and the extracellular matrix proteins. In this study, we evaluated the effects of shikonin analogue 93/637 (SA), derived from the plant Arnebia nobilis, on normal and hydrocortisone-induced impaired healing in full thickness cutaneous punch wounds in rats. SA (0.1%) was applied topically daily as an ointment in polyethylene glycol base on wounds. SA treatment significantly accelerated healing of wounds, as measured by wound contraction compared to controls in hydrocortisone-impaired animals. SA treatment promoted formation of granulation tissue including cell migration and neovascularization, collagenization and reepithelialization. The expression of basic fibroblast growth factor (bFGF) was higher as revealed by immunohistochemistry in treated wounds compared to controls. However, the expression of transforming growth factor-beta(1) was not affected by SA treatment. Since bFGF is known to accelerate wound healing, the increased expression of bFGF by SA may be partly responsible for the enhancement of wound healing. These studies suggest that SA could be further studied for clinical use to enhance wound healing.

Risk factors in neuroleptic malignant syndrome.

Neuroleptic malignant syndrome (NMS) is an uncommon but potentially serious idiosyncratic response to neuroleptic antipsychotics. It usually affects young males, but the risk has been seen to increase with certain factors including the administration practices of antipsychotic neuroleptics in these individuals. Even though no predictors for NMS are yet known, this article highlights the findings on certain risk factors as seen from a series of fifteen patients who developed NMS. Cautious use of neuroleptics in those at risk, early recognition and institution of immediate management is important.

Migratory pulmonary infiltrates in a patient with rheumatoid arthritis.

The case history is described of an elderly man with rheumatoid arthritis receiving treatment with sulfasalazine and the cyclooxygenase-2 inhibitor celecoxib who presented with severe shortness of breath, cough, and decreased exercise tolerance. The chest radiograph showed unilateral alveolo-interstitial infiltrates and a biopsy specimen of the lung parenchyma showed changes consistent with acute eosinophilic pneumonia. Antibiotic treatment was unsuccessful, but treatment with steroids and discontinuation of sulfasalazine and celecoxib resulted in a marked clinical improvement confirmed by arterial blood gas analysis. The condition may have developed as an adverse reaction either to sulfasalazine or to celecoxib, although hypersensitivity to the latter has not previously been reported.

Is repeat prostate biopsy for high-grade prostatic intraepithelial neoplasia necessary after routine 12-core sampling?

OBJECTIVES: To determine whether repeat biopsy is necessary when the diagnosis of high-grade prostatic intraepithelial neoplasia (HGPIN) is made with a 12-core biopsy. Repeated biopsy has been recommended for individuals with HGPIN noted on sextant prostate biopsy because of the high likelihood of cancer detection. Recently, we have recommended the routine use of 12 cores, rather than 6, to improve cancer detection. METHODS: The charts of all patients undergoing prostate biopsy during a 2-year period at the Manhattan Veterans Administration Medical Center were reviewed. Patients diagnosed with HGPIN on a 12-core biopsy were identified, and those undergoing a repeat 12-core biopsy within 1 year of the initial biopsy were evaluated to determine the rate of cancer detection. RESULTS: A total of 619 men underwent biopsy during the study period. Of 103 men diagnosed with HGPIN, 43 underwent a repeat biopsy within 1 year at the discretion of the managing urologist. The mean age and median prostate-specific antigen level of those undergoing a repeat biopsy was 65.5 years and 5.37 ng/mL, respectively. At the time of the repeat biopsy, 1 patient was found to have cancer (2.3%), 20 had HGPIN (46.5%), 20 had benign pathologic findings (46.5%), and 1 patient (2.3%) had atypical small acinar proliferation. CONCLUSIONS: A repeat biopsy after the diagnosis of HGPIN on 12-core prostate biopsy rarely results in cancer detection. In the absence of other factors increasing the suspicion of cancer, immediate repeat biopsy for HGPIN diagnosed on a 12-core biopsy is unnecessary.

Dissecting the electrostatic interactions and pH-dependent activity of a family 11 glycosidase.

Previous studies of the low molecular mass family 11 xylanase from Bacillus circulans show that the ionization state of the nucleophile (Glu78, pK(a) 4.6) and the acid/base catalyst (Glu172, pK(a) 6.7) gives rise to its pH-dependent activity profile. Inspection of the crystal structure of BCX reveals that Glu78 and Glu172 are in very similar environments and are surrounded by several chemically equivalent and highly conserved active site residues. Hence, there are no obvious reasons why their apparent pK(a) values are different. To address this question, a mutagenic approach was implemented to determine what features establish the pK(a) values (measured directly by (13)C NMR and indirectly by pH-dependent activity profiles) of these two catalytic carboxylic acids. Analysis of several BCX variants indicates that the ionized form of Glu78 is preferentially stabilized over that of Glu172 in part by stronger hydrogen bonds contributed by two well-ordered residues, namely, Tyr69 and Gln127. In addition, theoretical pK(a) calculations show that Glu78 has a lower pK(a) value than Glu172 due to a smaller desolvation energy and more favorable background interactions with permanent partial charges and ionizable groups within the protein. The pK(a) value of Glu172 is in turn elevated due to electrostatic repulsion from the negatively charged glutamate at position 78. The results also indicate that all of the conserved active site residues act concertedly in establishing the pK(a) values of Glu78 and Glu172, with no particular residue being singly more important than any of the others. In general, residues that contribute positive charges and hydrogen bonds serve to lower the pK(a) values of Glu78 and Glu172. The degree to which a hydrogen bond lowers a pK(a) value is largely dependent on the length of the hydrogen bond (shorter bonds lower pK(a) values more) and the chemical nature of the donor (COOH > OH > CONH(2)). In contrast, neighboring carboxyl groups can either lower or raise the pK(a) values of the catalytic glutamic acids depending upon the electrostatic linkage of the ionization constants of the residues involved in the interaction. While the pH optimum of BCX can be shifted from -1.1 to +0.6 pH units by mutating neighboring residues within the active site, activity is usually compromised due to the loss of important ground and/or transition state interactions. These results suggest that the pH optima of an enzyme might be best engineered by making strategic amino acid substitutions, at positions outside of the "core" active site, that electrostatically influence catalytic residues without perturbing their immediate structural environment.

Malignant fibrous histiocytoma arising in the upper posterior triangle of the neck.

We describe the case of a 59-year-old man who came to us with a right neck mass of 4 to 5 months' duration. A histologic diagnosis of malignant fibrous histiocytoma was made, and the patient underwent wide local excision and neck dissection followed by postoperative radiation therapy. We briefly discuss the characteristics and treatment of this rare entity.

Synchronous gastric adenocarcinomas in a patient with Meckel's diverticulum.

Meckel's diverticulum, which is the most common congenital anomaly of the gastrointestinal tract, occurs when the vitelline duct persists past the 7th week of gestation. Although complications may occur in 8% to 22% of patients with Meckel's diverticula, adenocarcinoma is very uncommon. We describe a patient with early gastric cancer who was incidentally found to have a superficial adenocarcinoma arising from ectopic gastric mucosa within a Meckel's diverticulum. To the best of our knowledge, synchronous gastric adenocarcinoma in a patient with Meckel's diverticulum has not been previously reported.