Inactivation of Listeria monocytogenes on and within Apples Destined for Caramel Apple Production by Using Sequential Forced Air Ozone Gas Followed by a Continuous Advanced Oxidative Process Treatment.

This study evaluated the efficacy of using sequential forced air ozone followed by an advanced oxidative process (AOP) treatment to inactivate Listeria monocytogenes on and within Empire apples. The forced air ozone treatment consisted of a reactor that introduced ozone (6 g/h) into an airstream that flowed through an apple bed (ca. 30 cm in depth). Before treatment, the apples were conditioned at 4°C to ensure that condensate had formed before the apples were transferred to the reactor. The condensate ensured sufficient relative humidity to enhance the antimicrobial action of ozone. Air was passed through the apple bed at 9.3 m/s, and the ozone was introduced after 10 min. The ozone concentration measured after exiting the apple bed reached a steady state of 23 ppm. A 20-min ozone treatment supported a 2.12- to 3.07-log CFU reduction of L. monocytogenes, with no significant effect of apple position within the bed. The AOP-based method was a continuous process whereby hydrogen peroxide was introduced as a vapor into a reactor illuminated by UV-C and ozone-emitting lamps that collectively generated hydroxyl radicals. Operating the AOP reactor with UV-C light (54-mJ cm2 dose), 6% (v/v) hydrogen peroxide, 2 g/h ozone, and a chamber temperature of 48°C resulted in a 3-log CFU reduction of L. monocytogenes on the surface of the apples and internally within the scar tissue. Applying a caramel coating, from a molten solution (at 80°C), resulted in a 0.5-log CFU reduction of L. monocytogenes on the apple surface. In apples treated with the sequential process, L. monocytogenes could only be recovered sporadically by enrichment and did not undergo outgrowth when the caramel apples were stored at 22°C for 19 days. However, growth of L. monocytogenes within the core, but not the surface, was observed from caramel apples prepared from nontreated control fruit.

White-tailed deer (Odocoileus virginianus) develop spirochetemia following experimental infection with Borrelia lonestari.

Borrelia lonestari is considered a putative agent of southern tick-associated rash illness (STARI) and is known to occur naturally only in lone star ticks (Amblyomma americanum) and white-tailed deer (Odocoileus virginianus). We used a low passage isolate of B. lonestari (LS-1) to inoculate white-tailed deer, C3H mice, Holstein cattle, and beagles. Animals were monitored via examination of Giemsa and acridine orange stained blood smears, polymerase chain reaction (PCR), indirect fluorescent antibody (IFA) test, and/or culture isolation. Spirochetes were visualized in blood smears of both deer on days post-inoculation (DPI) 6, 8, 12 and one deer on DPI 15. Whole blood collected from deer tested PCR positive starting on DPI 4 and remained positive as long as DPI 28. Both deer developed antibody titers of >64, with a maximum IFA titer of 1024. The organism was reisolated from the blood of both deer on DPI 6 and one deer on DPI 12. All isolation attempts from mice, calves, or dogs were negative, although one of seven mice was transiently PCR positive. Mice and dogs developed an IFA titer > or =64, while calves lacked a detectable antibody response. These preliminary experimental infection trials show that white-tailed deer are susceptible to infection with B. lonestari and develop a spirochetemia following needle-inoculation, while C3H mice, calves, and dogs do not. Results suggest that deer may serve as a vertebrate reservoir host. Tick transmission studies are needed to confirm that this organism can be maintained in a natural cycle involving deer and A. americanum.

Level of maternal antibody required to protect neonates against early-onset disease caused by group B Streptococcus type Ia: a multicenter, seroepidemiology study.

Because of the difficulty of conducting efficacy trials of vaccines against group B streptococcus (GBS), the licensure of these vaccines may have to rely on studies that measure vaccine-induced antibody levels that correlate with protection. This study estimates the level of maternal antibody required to protect neonates against early-onset disease (EOD) caused by GBS type Ia. Levels of maternal serum IgG GBS Ia antibodies, measured by ELISAs in 45 case patients (neonates with EOD caused by GBS Ia) and in 319 control subjects (neonates colonized by GBS Ia but without EOD) born at > or =34 weeks gestation were compared. The probability of developing EOD declined with increasing maternal levels of IgG GBS Ia antibody (P = .03). Neonates whose mothers had levels of IgG GBS Ia antibody > or =5 microg/mL had an 88% lower risk (95% confidence interval, 7%-98%) of developing type-specific EOD, compared with those whose mothers had levels < 0.5 microg/mL. A vaccine that induces IgG GBS Ia antibody levels > or =5 microg/mL in mothers can be predicted to confer a high degree of type-specific immunity to EOD to their infants.

Treatment of optic nerve sheath meningioma with three-dimensional conformal radiation.

PURPOSE: To report a patient recovering vision after three-dimensional conformal radiotherapy for optic nerve sheath meningioma. METHODS: Radiotherapy was delivered by a three-dimensional conformal technique in 28-180-cGy fractions. RESULTS: Visual acuity improved from 20/200 to 20/30, and the visual field defect resolved. CONCLUSION: Visual loss from optic nerve sheath meningioma can be reversed by three-dimensional conformal radiotherapy.

Proximal electromagnetic shear forces.

We perform a simple model calculation to estimate the electromagnetically induced shear force caused by a current dissipation when a charged tip is moved parallel to a conducting material. For parameters typical in shear force imaging, the force is many orders of magnitude below reported values. Thus, proximal electromagnetic tip-sample forces can be neglected in discussions of shear force imaging.

The puzzling association between smoking and hypertension during pregnancy.

OBJECTIVE: The object of this study was to examine the association between maternal smoking and hypertension during pregnancy. STUDY DESIGN: We used data from the Collaborative Perinatal Project, a large prospective cohort study that collected detailed information on blood pressure, proteinuria, smoking, and placental morphologic and histologic characteristics. A total of 9651 healthy primigravid women without chronic hypertension who had been enrolled in the study at the first or second trimester (average 18 weeks' gestation) and had had >/=3 prenatal visits were included. Gestational hypertension was defined as diastolic blood pressure >/=90 mm Hg on 2 occasions from 24 weeks' gestation to 2 weeks post partum. Preeclampsia was defined as gestational hypertension plus >/=2 urine samples containing >/=1+ protein according to dipstick measurement during the same gestational period. RESULTS: After we controlled for prepregnancy body mass, age, socioeconomic status, and race, both past smoking and smoking during pregnancy were associated in a dose-response pattern with reduced risks of gestational hypertension and preeclampsia. For women who smoked >/=10 cigarettes/d the relative risks with respect to women who had never smoked were 0.6 (95% confidence interval, 0.4-0.9) for gestational hypertension and 0.5 (95% confidence interval, 0.4-0.7) for preeclampsia. This protective effect was observed both for mild and severe gestational hypertension and for preeclampsia. The more and the longer a woman had smoked previously, the lower was her risk of development of hypertension during pregnancy. This association could not be explained by confounding factors, by changes in placental morphologic or histopathologic characteristics, by maternal net weight gain, or by elevated liver enzyme bioactivity. CONCLUSION: Smoking is associated with a reduced risk of hypertension during pregnancy. The protective effect appears to continue even after cessation of smoking. Further basic research on this issue is warranted.

Definition of emergency medicine.

This SAEM position paper clarifies the role of emergency medicine in health care delivery. It builds upon the working definition of emergency medicine developed by the American College of Emergency Physicians in 1994 by describing the health care role of emergency physicians (EPs). EPs are first-contact providers who care for all patients regardless of age, gender, time of presentation, or ability to pay. They remain the only continuously accessible specialty for patients seeking help and solace in the health care system. They are an essential link in the health care continuum between primary care physicians, specialists, the out-of-hospital system, the patient, inpatient services, and communication services. The EP's role is in organizing and monitoring the emergency care delivery system. Part of this role is to better align the health care provider training and ability with the specific medical needs of a patient. The emergency health care system remains the essential medical safety net for all individuals needing care in this country.

The 'Y2K bug': how to ease hospital equipment into the next millennium.

The advent of the 21st century is unlikely to wreak as much technologic havoc as the doomsayers have predicted. The Y2K problem is addressed by new programs that use a four-digit year code. Although hospitals must prioritize technology for Y2K compliance, they also need to address the issue actively: 2000 is less than 18 months away!

Operating room fires: how to prevent and minimize spread.

To prevent fires, a simple rule to remember is the "fire triangle" of oxygen, heat, and fuel. Minimizing oxygen enrichment will reduce the fire hazard. Proper protocols need to be established for the handling of heat-bearing units, such as electrosurgical pencils, electrocautery units, and lasers.

[beta-catenin overexpression in metastasized colorectal carcinoma--an important mechanism in progression of the disease?]. / beta-Catenin Uberexpression im metastasierenden colorectalen Carcinom--Ein wichtiger Mechanismus bei der Progression der Erkrankung?

The protein beta-catenin can not be degraded in CRC due to different reasons. This leads to an increased formation of beta-catenin/Tcf4 complex, which has a strong transcription factor activity. We investigated the mRNA expression of beta-catenin and Tcf4 in N, T and M in 12 cell lines and in tissues samples of 14 patients. We found a significant increase of beta-catenin mRNA expression in the primary tumors and in the metastases. These data show for the first time that apart from the known mechanisms the overexpression of beta-catenin mRNA can be an additional factor contributing to the increase of beta-catenin amount in cells of CRC. The resulting increased transcription of hitherto unknown target genes might be involved in the progression and the metastatic process of CRC.

Conjunctival epithelial cells can resurface denuded cornea, but do not transdifferentiate to express cornea-specific keratin 12 following removal of limbal epithelium in mouse.

Limbal stem cell deficiency contributes to recurrent corneal epithelial defects. We examined whether the conjunctival epithelium can transdifferentiate to corneal epithelium following surgically induced limbal stem cell deficiency. Mice were anesthetized by intraperitoneal injection of sodium pentobarbital. Partial or total epithelial removal was produced with a no. 69 Beaver blade under a dissecting microscope. The wounds were allowed to heal for 0-28 days, and the mice were examined every other day to evaluate re-epithelialization. Corneas were then subjected to histological, immunohistochemical studies and Western blot analysis with epitope-specific anti-keratin 12 antibodies. Partial epithelial defects re-epithelialized within 2 days and were normal in appearance and expressed cornea-specific keratin 12. In eyes with limbal deficiency, re-epithelialization progressed more slowly and was characterized by opacification; epithelial closure usually occurred by the 7th day. This epithelium differed from normal corneal epithelium in basic morphology, cell shape, and the presence of goblet cells at 2 weeks after injury. The epithelium at the center of injured corneas with total defect at 4 weeks had cornealike morphology and was devoid of goblet cells. These epithelial cells derived from conjunctiva did not express the cornea-specific keratin 12 as determined by immunohistochemistry, Western blot analysis and in situ hybridization. As evidenced by differences in morphology and the expression of cornea-specific keratin 12, conjunctival transdifferentiation does not occur in conjunctical overgrowth after the removal of limbal epithelium.

Evaluation of a solvent-softened gutta-percha obturation technique in curved canals.

The purpose of this study was to compare the efficacy of three obturation techniques in curved canals. Twenty-four sets of three (triplets) morphologically similar molars having root curvatures of 45 to 90+ degrees were assembled. Following canal preparation, one sample from each group was obturated by either a halothane-dipped, a chloroform-dipped, or an untreated lateral condensation technique. Twenty triplets were cleared, evaluated, and graded for homogeneity of fill, canal wall adaptation, and replication of internal anatomy. Four triplets had windows prepared to expose the apical 6 mm of filling and were viewed with scanning electron microscopy. Kruskal-Wallis test of cleared teeth indicated a significant difference in favor of the solvent-softened techniques (p = 0.01). There was no difference between chloroform- and halothane-dipped groups (p = 0.03). Scanning electron microscope evaluations of halothane-dipped samples revealed more homogeneous fills with greater canal replication than untreated gutta-percha. In addition, halothane-treated samples had appreciably less surface porosity than chloroform. Lateral condensation of halothane-treated gutta-percha was judged to be a viable obturation technique.

Integration of United States emergency medicine concepts into emergency services in the New Independent States.

At this writing, a collaborative partnership has been in place for 30 months between the Boston University Medical Center, the University of Massachusetts Medical Center, the Armenian Ministry of Health, and the Emergency Hospital of Yerevan, Armenia, to improve emergency and trauma care in that city. Fifty-five individuals have traveled to and from the Emergency Hospital, the partner hospital. The collaboration has led to the creation of the Emergency Medical Services Institute (EMSI) at Emergency Hospital, an 800-bed facility that serves as a trauma center and as base for the Yerevan ambulance system. A curriculum (text and slides) has been developed and translated into Armenian and Russian. To date, the Armenian EMSI has trained nearly 300 emergency medical personnel: physicians, nurses, drivers, and first responders. The Armenian EMSI faculty have received training in directing instruction of emergency care providers. Plans are in place to begin training in Armenian cities outside of Yerevan and in neighboring republics. An emergency medicine residency program received ministry approval and was begun with six resident physicians in January 1995. To date, 45 nurses have graduated from a 400-hour training program. This partnership program chose an education initiative as the vehicle for interaction between the United States and the formerly Soviet-directed Armenian health care system. Officials of the partner hospital requested assistance in upgrading the skills of its abundant emergency care workforce, citing cardiovascular disease, trauma, and accidents as leading causes of death and disability in Armenia.(ABSTRACT TRUNCATED AT 250 WORDS)

Analyzing dental practice value: doing your own appraisal.

Analyzing practice value consists of a simplified method of determining practice value that allows the dentist to periodically review and value his or her own practice. Three formulas are outlined and averaged, considering cash flow and how it can affect the total picture. The subjective portion of practice analysis is also detailed to show how practices with the same production levels and assets can have varying worth.