Economic feasibility of cooling dry cows across the United States.

Heat stress during the dry period reduces milk yield in the subsequent lactation of dairy cows. Our objectives were to quantify the economic losses due to heat stress if dry cows are not cooled and to evaluate the economic feasibility of dry cow cooling. We used weather data from the National Oceanic and Atmospheric Administration to calculate the number of heat stress days for each of the 50 US states. A heat stress day was declared when the daily average temperature-humidity index was ≥68. The number of dairy cows in each state in 2015 was obtained from the USDA-National Agricultural Statistics Service. We assumed that 15% of the cows were dry at any time, a 60-d dry period, and a calving interval of 400d. Only cows in their second or greater parity (65%) benefitted from cooling during the dry period of the previous parity. Milk yield decreased by 5kg in the subsequent lactation (340d) if the cow experienced heat stress during the dry period based on a review of the literature. The default marginal value of milk minus feed cost was $0.33/kg of milk. The investment analysis included purchases of fans and soakers and use of water and electricity. Investment in a dry cow barn was considered separately. The average US dairy cow would experience 96 (26%) heat stress days during the year if not cooled and loses 447kg of milk in the subsequent lactation if not cooled when dry. Annual losses would be $810 million if dry cows were not cooled ($87/cow per yr). For the top 3 milk-producing states (California, Wisconsin, New York), and Florida and Texas, the average milk losses in the subsequent lactation were 522, 349, 387, 1,197, and 904kg, and reduced profit per cow per year would be $101, $68, $75, $233, and $176, respectively. The average benefit-cost ratio and payback periods of cooling dry cows in the United States were 3.15 and 0.27 yr (dry cow barn already present) and 1.45 and 5.68 yr (if investing in a dry cow barn) in the default scenario. To reach positive net present values, 6d (barn is present) and 55d (barn investment necessary) of heat stress annually were necessary (default assumptions). Other benefits of cooling, such as increased health and more productive offspring, were not considered. In conclusion, cooling of dry cows was profitable for 89% of the cows in the United States when building a new barn is required (under default assumptions) and very profitable when construction of a dry cow barn is not required (except for Alaska).

Physiologic, health, and production responses of dairy cows supplemented with an immunomodulatory feed ingredient during the transition period.

This study compared physiological, health, and productive parameters in dairy cows supplemented or not with Omnigen-AF (OMN; Phibro Animal Health, Teaneck, NJ) during the transition period. Thirty-eight nonlactating, multiparous, pregnant Holstein × Gir cows were ranked by body weight (BW) and body condition score (BCS), and assigned to receive (n=19) or not (CON; n=19) OMN at 56 g/cow daily (as-fed basis) beginning 35 d before expected date of calving. Before calving, cows were maintained in single drylot pen with ad libitum access to corn silage, and received (as-fed basis) 3kg/cow daily of a concentrate. After calving, cows were moved to an adjacent drylot pen, milked twice daily, offered (as-fed basis) 35kg/cow daily of corn silage, and individually received a concentrate formulated to meet their nutritional requirements after both milkings. Cows received OMN individually as top-dressing in the morning concentrate feeding. Before calving, cow BW and BCS were recorded weekly and blood samples were collected every 5 d beginning on d -35 relative to expected calving date. After calving and until 46 d in milk, BW and BCS were recorded weekly, individual milk production was recorded, and milk samples were collected daily for total solids and somatic cell count analyses. Blood was sampled daily from 0 to 7 d in milk, every other day from 9 to 21 d in milk, and every 5 d from 26 to 46 d in milk. On 30 and 46 d in milk, cows were evaluated for endometritis via cytobrush technique, based on % of polymorphonuclear (PMN) cells in 100 total cell count (PMN + endometrial cells). On 48.7±1.6 d in milk, 9 cows/treatment received a lipopolysaccharide (LPS) injection (0.25µg/kg of BW), and blood was sampled hourly from -2 to 8 h, at 12-h intervals from 12 to 72 h, and at 24-h intervals form 96 to 120 h relative to LPS administration. No treatment differences were detected on BW, BCS, serum concentrations of cortisol, fatty acids, insulin, glucose, haptoglobin, cortisol, and insulin-like growth factor-I. Cows receiving OMN had greater milk yield (30.3 vs. 27.1kg/d) and percentage of PMN cells in endometrial cell population (12.2 vs. 3.9%) compared with CON cows. After LPS administration, cows receiving OMN had greater mean serum haptoglobin (212 vs. 94 µg/mL), as well as greater serum concentration of tumor necrosis factor α at 1, 2, and 3 h relative to LPS injection compared with CON cows. In conclusion, OMN supplementation during the transition period enhanced innate immunity parameters and increased milk production in dairy cows.

Mammary Paget's disease and radiotherapy: a systematic literature review.

OBJECTIVE: Paget disease of the breast (PDB) is a rare form of cutaneous breast cancer. Up to date, no randomized studies evaluated the different management strategies. This systematic review investigates the role of radiotherapy and its best technical profile in the treatment of this disease, with great attention to doses and fractionation regimens. MATERIALS AND METHODS: A systematic search was performed on PubMed, Embase and Scopus in order to detect case reports, case series and prospective as well as retrospective clinical studies describing histologically proven PDB and providing information about pertinent radiation treatments. Searching strategy followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. RESULTS: Inclusion criteria were met by six papers, dealing with radiation treatments performed postoperatively and in exclusive settings. No evaluations were performed on preoperative radiotherapy. CONCLUSIONS: Actually, the standard treatment of PDB reflects oncological principles of breast carcinoma therapy, including the role of breast-preserving surgery. The traditional radiotherapic dose is 50 Gy, with daily fractionation of 2 Gy. Adjuvant radiotherapy following breast preserving surgery represents the current standard of care; prospective studies could be of help in defining the role of exclusive radiotherapy, hypofractionated schemes and smaller target volumes.

Ovulation and fertility response to commercially available GnRH products in lactating cows synchronized with the Double-Ovsynch protocol.

This study was designed to evaluate whether commonly used gonadorelin products that are commercially available in the United States results in comparable ovulation and pregnancy per AI (P/AI) in synchronized lactating dairy cows. A total of 1411 Holstein cows receiving a Double-Ovsynch protocol (DOV) for conducting the first postpartum AI were randomized to receive one of the following GnRH products throughout the Double-Ovsynch: 1) Cystorelin® (CYS, gonadorelin diacetate tetrahydrate, n = 484); 2) Factrel® (FAC, gonadorelin hydrochloride, n = 482) or; 3) Fertagyl® (FER, gonadorelin diacetate tetrahydrate, n = 515). A subgroup of cows (n = 487) received ovarian ultrasound exams and collection of blood samples for progesterone (P4) analysis. Proportion of cows ovulating following the 3rd GnRH of DOV tended (P = 0.07) to differ between GnRH salts (hydrochloride = 61.5% vs. diacetate = 72.7%) but was similar for GnRH products (FER = 74.1% vs. FAC = 61.5% vs. CYS = 72.2%). Interestingly, a logistic regression analyses that considered the circulating P4 at the time of GnRH treatment indicated lower ovulation responses to FAC compared to FER and CYS; although greater circulating P4 decreased ovulation response to all GnRH products. Results for P/AI at 60 d post-insemination differed between GnRH salts (P = 0.02) as well as GnRH products (FER = 47.8% vs. FAC = 42.0% vs. CYS = 49.8%; P = 0.04). In conclusion, fertility following use of the Double-Ovsynch was less following a hydrochloride-based GnRH product likely due to lesser ovulatory responses throughout the synchronization protocol.

Shall we operate? Preoperative assessment in elderly cancer patients (PACE) can help. A SIOG surgical task force prospective study.

BACKGROUND: A number of elderly cancer patients do not receive standard surgery for solid tumors because they are considered unfit for treatment as a consequence of inaccurate estimation of the operative risk. To tailor treatment to onco-geriatric series, oncologists are now beginning to use a comprehensive geriatric assessment (CGA). This study investigates the value of an extended CGA in assessing the suitability of elderly patients for surgical intervention. PATIENTS AND METHODS: Preoperative assessment of cancer in the elderly (PACE) incorporates validated instruments including the CGA, an assessment of fatigue and performance status and an anaesthesiologist's evaluation of operative risk. An international prospective study was conducted using 460 consecutively recruited elderly cancer patients who received PACE prior to elective surgery. Mortality, post-operative complications (morbidity) and length of hospital stay were recorded up to 30 days after surgery. RESULTS: Poor health in relation to disability (assessed using the instrumental activities of daily living (IADL)), fatigue and performance status (PS) were associated with a 50% increase in the relative risk of post-operative complications. Multivariate analysis identified moderate/severe fatigue, a dependent IADL and an abnormal PS as the most important independent predictors of post-surgical complications. Disability assessed by activities of daily living (ADL), IADL and PS were associated with an extended hospital stay. CONCLUSION: PACE represents a valuable tool in enhancing the decision process concerning the candidacy of elderly cancer patients for surgical intervention and can reduce inappropriate age-related inequity in access to surgical intervention. It is recommended that PACE be used routinely in surgical practice.

Chemical process to separate iron oxides particles in pottery sample for EPR dating.

Ancient potteries usually are made of the local clay material, which contains relatively high concentration of iron. The powdered samples are usually quite black, due to magnetite, and, although they can be used for thermoluminescene (TL) dating, it is easiest to obtain better TL reading when clearest natural or pre-treated sample is used. For electron paramagnetic resonance (EPR) measurements, the huge signal due to iron spin-spin interaction, promotes an intense interference overlapping any other signal in this range. Sample dating is obtained by dividing the radiation dose, determined by the concentration of paramagnetic species generated by irradiation, by the natural dose so as a consequence, EPR dating cannot be used, since iron signal do not depend on radiation dose. In some cases, the density separation method using hydrated solution of sodium polytungstate [Na6(H2W12O40).H2O] becomes useful. However, the sodium polytungstate is very expensive in Brazil; hence an alternative method for eliminating this interference is proposed. A chemical process to eliminate about 90% of magnetite was developed. A sample of powdered ancient pottery was treated in a mixture (3:1:1) of HCl, HNO(3) and H(2)O(2) for 4h. After that, it was washed several times in distilled water to remove all acid matrixes. The original black sample becomes somewhat clearer. The resulting material was analyzed by plasma mass spectrometry (ICP-MS), with the result that the iron content is reduced by a factor of about 9. In EPR measurements a non-treated natural ceramic sample shows a broad spin-spin interaction signal, the chemically treated sample presents a narrow signal in g=2.00 region, possibly due to a radical of (SiO(3))(3-), mixed with signal of remaining iron [M. Ikeya, New Applications of Electron Spin Resonance, World Scientific, Singapore, 1993, p. 285]. This signal increases in intensity under gamma-irradiation. However, still due to iron influence, the additive method yielded too old age-value. Since annealing at 300 degrees C, Toyoda and Ikeya [S. Toyoda, M. Ikeya, Geochem. J. 25 (1991) 427-445] states that E1'-signal with maximum intensity is obtained, while annealing at 400 degrees C E1'-signal is completely eliminated, the subtraction of the second one from 300 degrees C heat-treated sample isolate E1'-like signal. Since this is radiation dose-dependent, we show that now EPR dating becomes possible.

Early detection of cancer: ideas for a debate.

Even if the overall number of cancer is increasing, the mortality has started to decrease in the Western World. The role of early detection in this decrease is a matter of debate. To assess its impact on mortality it is important to distinguish between diagnosis of cancer in symptomatic patients, and early detection in asymptomatic individuals who may self-refer or who may be offered ad hoc or systematic screening. The policies for early detection and screening vary greatly between European countries, despite many similarities in their cancer burden, and this partly reflects the uncertainties surrounding asymptomatic testing for cancer. A Task Force of European expert, held in Azzate (VA), Italy, established to address these issues, acknowledged the need for more research in the field of individual risk assessment since general statistics are more and more perceived as inadequate to design personal early detection plans. The group also recognised that combinations of early detection and screening will enforce the effectiveness of new treatments in curbing mortality curves, although policies will vary with different cancers.

Pre-operative assessment of cancer in the elderly (PACE): a comprehensive assessment of underlying characteristics of elderly cancer patients prior to elective surgery.

BACKGROUND: Cancer is a disease that particularly affects the elderly and, although surgery is the first treatment choice, many elderly cancer patients do not receive standard surgery because they are considered unfit for treatment due to an inaccurate estimation of operative risk. Pre-operative Assessment of Cancer in the Elderly (PACE) was developed in order to address the need to provide detailed information about the functional reserve of the elderly cancer patient to aid individualised management. METHODS: PACE incorporates a battery of validated instruments including the Comprehensive Geriatric Assessment (CGA), Brief Fatigue Inventory (BFI), Eastern Cooperative Oncology Group Performance Status (ECOG-PS), and American Society Anesthesiologists (ASA) grade. An international prospective study was conducted with 460 consecutive elderly cancer patients (216 breast, 146 GIT, 71 GUT, 27 other) receiving PACE prior to receiving elective surgery. RESULTS: Three hundred and eighty four patients (83.4%) were observed to have at least one co-morbidity; the most common being hypertension (n=246, 53.5%). More than two thirds of the patients had good functional and mental status according to PACE. After adjusting for age, sex and type of cancer, six of the seven items of PACE were found to be significantly associated with co-morbidities (according to the Satariano's Index of Co-morbidities (SIC)). A multivariate analysis identified IADL, BFI and ASA to be the most important instruments in explaining SIC. DISCUSSION: PACE has been effectively used to describe the functional capacity and health status in an international cohort of elderly cancer patients. The majority of PACE instruments have been found to be significantly associated with co-morbidities (SIC) and can distinguish between type and severity of cancer. PACE represents a useful tool in evaluating onco-geriatric fitness for surgery.

Fat grafting for breast cancer patients: From basic science to clinical studies.

Fat grafting in the surgical treatment of breast cancer has become popular in a short period of time because of the rising expectations of good esthetic results by the patients as well as the simplicity of the technique; however, the oncological safety for breast cancer patients remains a matter of debate. The procedure raises many questions considering that recent in-vitro studies have shown that fat grafting could promote tumor recurrence through diverse mechanisms, or even facilitate distant metastasis. We present a review of the currently available experimental and clinical data in order to describe and discuss patient selection criteria following breast cancer surgery.

Irradiation with standard tangential breast fields in patients treated with conservative surgery and sentinel node biopsy: using a three-dimensional tool to evaluate the first level coverage of the axillary nodes.

Recent data show that axillary coverage can be obtained, but only through a selective CT-based treatment planning, as standard tangential fields are inadequate to deliver therapeutic doses. Currently, the replacement of axillary dissection with new techniques, such as sentinel node (SN) biopsy, makes it necessary to re-address the question about the real role of axillary irradiation, complicated by the differences in the anatomy of dissected and undissected axillary regions. The purpose of this paper is the dosimetric analysis of first axillary level coverage in standard irradiation of 15 breast-cancer patients treated with quadrantectomy and SN biopsy (negative finding). During surgery a clip on the site of the SN was positioned, marking the caudal margin of first axillary level. After the breast treatment plan was completed, the first axillary level was contoured on CT scans, from the site of the surgical clip up to the sternal manubrium, for coverage analysis with dose-volume histograms (DVHs) and three-dimensional isodose visualization. The maximum dose mean ranged from 5% to 80% of the prescribed dose (mean value 48.7%). The mean total dose received by the volume of interest was lower than 40 Gy in all but one patient. No patient had total irradiation of first nodal level; only one patient had 35% of the volume enclosed in the 100% isodose. Our analysis lead to the conclusion that therapeutic doses are not really delivered to first level axillary level nodes by a standard tangential field technique, and that specific treatment planning and beam arrangement are required when adequate coverage is necessary.

Evaluation of skin perfusion after nipple-sparing mastectomy by indocyanine green dye. Preliminary results.

The aim of the study was to investigate the blood supply of the normal nipple areola complex (NAC) and the spared areola complex after a nipple-sparing mastectomy using the analysis of the fluorescence from the indocianine green dye (ICG) injection. Between December 2002 and July 2003 we performed the ICG analysis in 10 cases of healthy breasts and in 9 patients after a nipple-sparing mastectomy and one patient after subcutaneous mastectomy. In all cases, the resulting fluorescence was measured in three different zones: nipple, areola, surrounding mammary skin. Three parameters of the fluorescence curve (slope, maximum intensity, time to achieve a maximum level) were recorded. On the healthy breast, the nipple showed a very high perfusion as compared to the other zones. On the contrary, after the mastectomy the fluorescent pattern was completely altered, being the perfusion of the nipple very low. In conclusion, these preliminary results confirm the applicability and the importance of the ICG technique for evaluating the perfusion of the healthy and spared areola after surgery. Because of the small number of patients further studies are needed.

The surgical management of elderly cancer patients; recommendations of the SIOG surgical task force.

Although cancer in the elderly is extremely common, few health professionals in oncology are familiar with caring for series of oncogeriatric patients. Surgery is at present the first choice, but is frequently delivered suboptimally: under-treatment is justified by concerns about unsustainable toxicity, whilst over-treatment is explained by the lack of knowledge in optimising preoperative risk assessment. This article summarises the point of view of the Surgical Task Force @ SIOG (International Society for Geriatric Oncology), pointing out differences from, and similarities to, the younger cohorts of cancer patients, and highlighting the latest updates and trends specifically related to senior cancer patients.

Verification of electron beam therapy with conventional and storage phosphor images: preliminary experience.

Portal verification images were generated by the photon contamination in electron beams produced by a linear accelerator during treatment of patients receiving high-energy electron radiation therapy. Both conventional and storage phosphor methods yielded projection radiographs in which anatomy of the irradiated and surrounding tissue was demonstrated. Exposed phantoms were used to confirm that the images represent a true projection of the radiation field. A preliminary series of 22 cases was evaluated by two radiotherapists and judged subjectively to be of clinical value. Geometric error, or more importantly, the lack thereof, during high-energy electron treatments was easily confirmed with this method. In three cases, the treatment protocol was corrected based on the images obtained. Because the readout process of storage phosphor images allows for gain adjustments and post-processing, the images obtained with this method were found to delineate anatomy in the treated and surrounding tissues somewhat more consistently than could conventional images.

Sentinel node localisation: A new prospective in the treatment of nodal melanoma metastases.

Sentinel node (SN) mapping and biopsy is a procedure that accurately stages the regional lymph node (LN) basin. Defined patterns of lymphatic drainage allow intraoperative determination of the first (sentinel) lymph node in the regional basin, and the absence of metastatic disease in the SN accurately reflects the absence of melanoma in the remaining regional nodes. The use of radiocolloid and a hand-held gamma detecting probe (GDP) together with a vital blue dye provides optimal results, and allows for the successful identification of the SN in over 99% of the procedures. Close collaboration between surgeons, nuclear radiologists and pathologists is required to ensure optimal results. Examination of serially sectioned SNs by hematoxylin-eosin staining (H&E), immunohistochemical staining and perhaps in the near future RT-PCR should reduce the number of patients with missed microscopic melanoma in the regional lymph nodes. Furthermore, the survival benefit recently reported in patients with melanoma metastatic to regional nodes using high dose of interferon alpha-2b signals that the surgeons should aggressively examine patients for the presence of occult regional melanoma metastases. Intraoperative SN mapping and SN biopsy are cost-effective procedures that allows accurate identification of regional lymph nodes that contain metastatic melanoma.

Heparan sulfate increases survival during gut-derived sepsis by decreasing bacterial translocation and enhancing host defense.

The effect of heparan sulfate (HS) on survival rate, bacterial translocation, and host defense was studied in a model of gut-derived sepsis that included transfusion-induced immunosuppression. Balb/c mice were treated pre- and postburn injury and bacterial challenge with HS, 5 mg/kg/day, or sterile phosphate-buffered saline. The HS pre- and postburn treated animals showed a significant improvement in survival compared to control animals (80 vs. 30%, p = .004, and 60 vs. 20%, p = .02, respectively). A lower amount of translocation was observed in the spleen (p < or = .001) of the HS group compared to control group. Quantitative colony counts and the calculated percentage of viable bacteria showed that the ability to kill translocated organisms was enhanced in all tissues of the animals receiving HS. These data suggest that treatment with HS positively affects the outcome in gut-derived sepsis. The beneficial effect was related both to an improved gut barrier function and to an enhanced host defense.

Effects of the angiotensin converting enzyme inhibitor enalapril on bacterial translocation after thermal injury and bacterial challenge.

Burn injury and sepsis produce acute gastrointestinal derangements that may predispose patients to bacterial translocation. We studied the effects of enalapril, an angiotensin converting enzyme inhibitor (ACEI), on gastrointestinal anatomic alterations, bacterial translocation, and related mortality during gut-derived sepsis in burned mice that had received a prior bacterial challenge. BALB/c mice (n = 111) were treated with enalapril 10 or 1 mg/kg body weight or sterile saline as control twice daily for 3 days. They were then gavaged with 10(a)111 in radiolabeled or unlabeled Escherichia coli and given a 20% total body surface area (TBSA) burn injury. Animals gavaged with unlabeled bacteria were observed for survival (n = 60). Survival was significantly higher in the group receiving enalapril 10 mg/Kg compared with control (75% vs. 10%). Mice treated with enalapril maintained small intestine weight, measured 4 h postburn, and ileal mucosal height was preserved, whereas burned untreated animals lost intestinal weight and mucosal height. Bacterial translocation was decreased in mice treated with enalapril, but killing was unaffected. This study suggests that treatment with enalapril positively affects the outcome in gut-derived sepsis by ameliorating gastrointestinal structural and functional damage and decreasing bacterial translocation.

A prospective, randomized, controlled clinical trial of tissue adhesive (2-octylcyanoacrylate) versus standard wound closure in breast surgery.

BACKGROUND: Recent studies suggest that the use of tissue adhesive for closure of both traumatic lacerations and incisional surgical wounds leads to cosmetic outcome comparable to conventional sutures. To date, no studies have investigated tissue adhesive in breast surgery and costs. Our aim was to compare the tissue adhesive 2-octylcyanoacrylate (OCA) with standard suture in breast surgery. METHODS: A prospective randomized study was conducted in which 151 patients were assessed for eligibility, and 133 were randomly allocated to skin closure with OCA adhesive or monofilament suture. Cosmetic outcome with blinded assessment, wound management by the patients, complication rates, and economic outcome were recorded. RESULTS: There was no difference in cosmetic score in the 2 groups, nor in complications at the early, 6-month, and 1-year follow-up. Patient satisfaction with the wound closed with OCA was rated significantly higher when compared with standard suture (P <.0001). The application of the tissue adhesive was significantly faster than that for standard suture (P <.001). In economic terms total costs were less in the tissue adhesive group, mainly due to lower postoperative costs of physician and assistant services (P <.001). CONCLUSIONS: OCA is effective and reliable in skin closure for breast surgery, yielding similar cosmetic results to standard suture. OCA is faster than standard wound closure and offers several practical advantages over suture repair for patients. Cost analysis has found that OCA adhesive can significantly decrease health care costs.

Sentinel node localization in primary melanoma: preoperative dynamic lymphoscintigraphy, intraoperative gamma probe, and vital dye guidance.

BACKGROUND: Sentinel node (SN) biopsy can be used to select patients with primary melanoma for therapeutic lymphadenectomy. The aim of the study was to assess the efficacy of 3 methods to locate the SN: preoperative dynamic lymphoscintigraphy, intraoperative patent blue dye (PBD), and gamma-detecting probe (GDP). METHODS: We studied 133 patients with cutaneous melanoma and clinically negative lymph nodes. Within 24 hours before surgery, colloid labeled with technetium 99m was injected intradermally around the site of the primary melanoma. The patients were studied before their operations by using dynamic lymphoscintigraphy. A total of 208 SNs were found in 164 lymph node basins. In addition, all the patients had PBD injected immediately before the surgical procedure. When the blue-stained node was identified intraoperatively, its radioactivity level was measured with the GDP. In the absence of blue coloration, the GDP was used to trace the SN. RESULTS: Of 208 SNs, 168 (80.8%) were identified in the regional draining basin during intraoperative lymphatic mapping by using PBD. By using the GDP method, 202 (97.1%) of 208 were identified (GDP vs PBD; P < .01). By combining the 2 methods, 206 (99%) of 208 SNs were detected. Of the 133 patients, 29 (21.8%) had pathologically positive SNs, and were subsequently subjected to regional lymphadenectomy. In 26 (89.7%) of 29 patients, the SN was the only node with metastasis. Three cases (10.3%) of recurrence in patients with microscopic SN metastasis and 7 cases (6.7%) of recurrence in patients without SN metastasis were found during a median follow-up of 566 days. CONCLUSIONS: Preoperative dynamic lymphoscintigraphy and intraoperative mapping with PBD and GDP offer simple and reliable methods of staging regional lymph nodes without subjecting every patient to a regional lymphadenectomy.

Effects of hyperoxia on bacterial translocation and mortality during gut-derived sepsis.

BACKGROUND: While hyperoxia is commonly used for treating carbon monoxide poisoning, chronic nonhealing ulcers, acute traumatic and chronically ischemic wounds, and refractory osteomyelitis, its efficacy is unproven in numerous clinical situations, including treatment during severe sepsis. OBJECTIVE: To test the effects of hyperoxia on bacterial translocation and mortality during gut-derived sepsis in a clinically relevant model of infection. METHODS: Balb/c mice were gavaged with 10(9) Escherichia coli and subjected to a 20% burn injury. Then, the animals were randomized to receive hyperoxia for different periods of time. Survival and the extent of translocation were determined, as well as intestinal histologic features. RESULTS: Hyperoxia treatment preserved gut morphology and improved gut barrier function, decreasing the amount of bacterial translocation. Short-term (4- or 8-hour) hyperoxia (100% oxygen) treatment improved survival only on day 1 after injury but did not affect the final outcome. Short-term (8-hour) hyperoxia (100% oxygen) plus 5-day 40% oxygen environment significantly improved long-term survival. CONCLUSION: Tissue pO2 may be an important regulator of gut barrier function. Hyperoxia treatment appears to play a major role in preserving gut barrier function.

Effects of antimurine interleukin-6 on bacterial translocation during gut-derived sepsis.

BACKGROUND: Recent studies have shown that interleukin-6 (IL-6) is involved in the systemic changes that are associated with infection and tissue injury and that there is a correlation between high levels of IL-6 and poor outcome during several pathologic conditions. OBJECTIVE: The effects of antimurine IL-6 antibody on survival and host defense were studied in a clinically relevant model of infection. METHODS: Balb/c mice were treated with 10 micrograms of antimurine interleukin-6, a nonspecific mouse IgG, or placebo 1 hour before they underwent bacterial challenge by gavage of 10(10) Escherichia coli and burn injury. Survival and the extent of translocation of E coli were determined as well as the correlation between the IL-6 levels and survival times. RESULTS: Survival after burn and gavage was 90% in animals treated with antimurine interleukin-6 vs 50% in animals treated with nonspecific IgG and 30% in saline-treated controls. A significant correlation between the levels of IL-6 and survival time was observed. Less translocation and better killing of bacteria were observed in the tissues of animals treated with antimurine interleukin-6. CONCLUSIONS: Interleukin-6 appears to play a major role in both the intensity of translocation of E coli from the intestine following burn injury and the host's ability to kill translocated organisms. Improved outcome was associated with a reduction of IL-6 levels by anti-IL-6 antibody.