Dark Matter Search Results from the PICO-60 C_{3}F_{8} Bubble Chamber.

New results are reported from the operation of the PICO-60 dark matter detector, a bubble chamber filled with 52 kg of C_{3}F_{8} located in the SNOLAB underground laboratory. As in previous PICO bubble chambers, PICO-60 C_{3}F_{8} exhibits excellent electron recoil and alpha decay rejection, and the observed multiple-scattering neutron rate indicates a single-scatter neutron background of less than one event per month. A blind analysis of an efficiency-corrected 1167-kg day exposure at a 3.3-keV thermodynamic threshold reveals no single-scattering nuclear recoil candidates, consistent with the predicted background. These results set the most stringent direct-detection constraint to date on the weakly interacting massive particle (WIMP)-proton spin-dependent cross section at 3.4×10^{-41} cm^{2} for a 30-GeV c^{-2} WIMP, more than 1 order of magnitude improvement from previous PICO results.

One Health approach to controlling a Q fever outbreak on an Australian goat farm.

A recent outbreak of Q fever was linked to an intensive goat and sheep dairy farm in Victoria, Australia, 2012-2014. Seventeen employees and one family member were confirmed with Q fever over a 28-month period, including two culture-positive cases. The outbreak investigation and management involved a One Health approach with representation from human, animal, environmental and public health. Seroprevalence in non-pregnant milking goats was 15% [95% confidence interval (CI) 7-27]; active infection was confirmed by positive quantitative PCR on several animal specimens. Genotyping of Coxiella burnetii DNA obtained from goat and human specimens was identical by two typing methods. A number of farming practices probably contributed to the outbreak, with similar precipitating factors to the Netherlands outbreak, 2007-2012. Compared to workers in a high-efficiency particulate arrestance (HEPA) filtered factory, administrative staff in an unfiltered adjoining office and those regularly handling goats and kids had 5·49 (95% CI 1·29-23·4) and 5·65 (95% CI 1·09-29·3) times the risk of infection, respectively; suggesting factory workers were protected from windborne spread of organisms. Reduction in the incidence of human cases was achieved through an intensive human vaccination programme plus environmental and biosecurity interventions. Subsequent non-occupational acquisition of Q fever in the spouse of an employee, indicates that infection remains endemic in the goat herd, and remains a challenge to manage without source control.

Dark Matter Search Results from the PICO-2L C3F8 Bubble Chamber.

New data are reported from the operation of a 2 liter C3F8 bubble chamber in the SNOLAB underground laboratory, with a total exposure of 211.5 kg days at four different energy thresholds below 10 keV. These data show that C3F8 provides excellent electron-recoil and alpha rejection capabilities at very low thresholds. The chamber exhibits an electron-recoil sensitivity of <3.5×10(-10) and an alpha rejection factor of >98.2%. These data also include the first observation of a dependence of acoustic signal on alpha energy. Twelve single nuclear recoil event candidates were observed during the run. The candidate events exhibit timing characteristics that are not consistent with the hypothesis of a uniform time distribution, and no evidence for a dark matter signal is claimed. These data provide the most sensitive direct detection constraints on WIMP-proton spin-dependent scattering to date, with significant sensitivity at low WIMP masses for spin-independent WIMP-nucleon scattering.

Pituitary adenylate cyclase-activating polypeptide (PACAP) in the bed nucleus of the stria terminalis (BNST) increases corticosterone in male and female rats.

Single nucleotide polymorphisms (SNP) in the genes for pituitary adenylate cyclase-activating polypeptide (PACAP) and the PAC1 receptor have been associated with several psychiatric disorders whose etiology has been associated with stressor exposure and/or dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. In rats, exposure to repeated variate stress has been shown to increase PACAP and its cognate PAC1 receptor expression in the bed nucleus of the stria terminalis (BNST), a brain region implicated in anxiety and depression-related behaviors as well as the regulation of HPA axis activity. We have argued that changes in BNST PACAP signaling may mediate the changes in emotional behavior and dysregulation of the HPA axis associated with anxiety and mood disorders. The current set of studies was designed to determine whether BNST PACAP infusion leads to activation of the HPA axis as determined by increases in plasma corticosterone. We observed an increase in plasma corticosterone levels 30min following BNST PACAP38 infusion in male and female rats, which was independent of estradiol (E2) treatment in females, and we found that plasma corticosterone levels were increased at both 30min and 60min, but returned to baseline levels 4h following the highest dose. PACAP38 infusion into the lateral ventricles immediately above the BNST did not alter plasma corticosterone level, and the increased plasma corticosterone following BNST PACAP was not blocked by BNST corticotropin releasing hormone (CRH) receptor antagonism. These results support others suggesting that BNST PACAP plays a key role in regulating stress responses.

Localised Mycobacterium ulcerans infection in four dogs.

Localised infection caused by Mycobacterium ulcerans is described in two Kelpies, a Whippet and a Koolie domiciled on the Bellarine Peninsula, Victoria, Australia. The diagnosis was confirmed using real-time polymerase chain reaction (PCR) targeting the M. ulcerans-specific insertion sequence (IS2404) in DNA extracted from swabs of ulcerated lesions in all cases. Where available, molecular typing confirmed that three of the dogs were infected with a strain of M. ulcerans that was indistinguishable from a disease-causing strain in people and other animals in Victoria. One dog was still undergoing treatment at the time of writing, but the remaining three dogs were successfully treated with a combination of surgical debridement and medical therapy in one case, and medical therapy alone in the other two. Investigation of the home environs of three of the dogs using real-time PCR revealed low amounts of M. ulcerans DNA in various environmental samples. Mycobacterium ulcerans infection should be included in the differential diagnoses of any ulcerated skin lesions in dogs that live in or visit endemic areas of Victoria and Queensland.

SNOLL. Sentinel node and occult (impalpable) lesion localization in breast cancer.

AIM: To evaluate the efficacy and safety for use of dual radioisotopes for localization of occult (impalpable) breast lesions and sentinel node biopsy as a combined technique (SNOLL) using a lower dose than previous studies. MATERIALS AND METHODS: One hundred and twenty-seven SNOLL procedures were performed. The impalpable breast lesions were localized with an intra-lesion injection of 0.2 ml of (99m)Tc MAA (1 MBq) with a particle size of 10-90 µm (radio-guided occult lesion localization, or ROLL) 1 to 4 h before surgery. Sentinel node localization was performed using 0.2 mls of (99)Tc nanocolloid (20 MBq) particle size no greater than 80 nm injected subdermally in the periareolar region within the index quadrant, the night before or the morning of surgery. RESULTS: Lesion localization was consistently achieved with a lower dose than that described in other studies without the need to use scintigraphy or additional imaging with radioopaque contrast medium. One hundred percent lesion localization with a negative clearance margin of 94.8% and 100% sentinel node localization was achieved. The use of dual radioisotopes with the lower dose used for ROLL did not compromise the localization of the impalpable lesion or the sentinel nodes. CONCLUSION: The combined use of radioisotopes for lesion and sentinel node removal is feasible and reliable with the lower radioisotope dose suggested compared with previously published studies. This method should be recommended as a standard procedure for SNOLL.

Long-term outcomes after ROLL lumpectomy.

BACKGROUND: Occult breast lesions are being successfully targeted by means of Radioactive-guided Occult Lesion Localization (ROLL). Several reports demonstrate suitability of ROLL technique to excise non-palpable breast lesions with immediate advantages. AIM: Evaluation of long-term outcomes after ROLL guided lumpectomy for early breast cancer. MATERIALS AND METHODS A CONSECUTIVE SERIES OF NON PALPABLE EARLY INVASIVE BREAST CANCERS EXCISED WITH ROLL (151 PTS; DECEMBER 2002#ENTITYSTARTX02013;JUNE 2006) WERE FOLLOWED UP FOR LONG-TERM OUTCOMES, I.E. LOCAL AND/OR SYSTEMIC RECURRENCE. OUR FOLLOW-UP PROTOCOL INCLUDED 6 MONTHLY PHYSICIAN ADMINISTERED CLINICAL EXAMINATIONS AND 18 MONTHLY IMAGING, I.E. MAMMOGRAM. BONE SCAN, LIVER AND BRAIN IMAGING WERE REQUESTED ON CLINICAL NEED. CLINICAL AND/OR RADIOLOGICAL SUSPICIOUS LESIONS FOR LOCAL RECURRENCE WERE CONFIRMED PATHOLOGICALLY: RESULTS: The median follow-up was 46 months with all patients having a minimum 22 months follow-up. 3/151 local recurrences occurred (1.98%). CONCLUSIONS: Long-term outcomes, i.e. local recurrence of invasive breast cancer excised with ROLL guidance compares well with existing localization techniques.

The CB(1) antagonist rimonabant is adjunctively therapeutic as well as monotherapeutic in an animal model of Parkinson's disease.

Acute injections of 8mg/kg of 3,4-dihydroxy-l-phenylalanine (l-DOPA) or 0.05mg/kg rimonabant equally improved contralateral forepaw stepping in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions, and their combination improved stepping more than either drug alone. However, 0.05mg/kg rimonabant did not alter the changes in stepping produced by acute injections of a dyskinesic dose of 35mg/kg l-DOPA. Thus, not only is a cannabinoid antagonist monotherapeutic in this animal model of Parkinson's disease, but it also enhances the therapeutic effect of a moderate, but not a high, dose of l-DOPA.

Recurrence after ROLL lumpectomy for invasive breast cancer.

BACKGROUND: Impalpable breast lesions are being successfully targeted by means of radio-guided occult lesion localisation (ROLL). Although ROLL allows adequate removal of sub-clinical breast lesions within a smaller volume of glandular tissue no long-term outcomes have been reported. AIM: To evaluate the recurrence of invasive cancer after ROLL lumpectomy. METHODS: A consecutive series of impalpable invasive breast cancers excised with ROLL (151 pts; Dec 2002-June 2006) has been followed up for local and/or systemic recurrence with six monthly clinical examinations and 18 monthly mammograms. Bone scan, liver and brain imaging were requested when clinically appropriate. Clinical and/or radiological suspicious lesions for local recurrence were confirmed pathologically. RESULTS: The median follow-up was 33 months with all patients having a minimum 22 months follow-up. Three (out of 151 impalpable invasive cancers) local recurrences occurred (1.98%). CONCLUSIONS: Local recurrence of sub-clinical invasive breast cancer excised with radioisotope guidance compares well with the existing localisation techniques. Its implementation is highly recommended.

Leptotrichia endocarditis: report of two cases from the International Collaboration on Endocarditis (ICE) database and review of previous cases.

Leptotrichia species typically colonize the oral cavity and genitourinary tract. We report the first two cases of endocarditis secondary to L. goodfellowii sp. nov. Both cases were identified using 16S rRNA gene sequencing. Review of the English literature revealed only two other cases of Leptotrichia sp. endocarditis.

Tumour localisation with a metal coil before the administration of neo-adjuvant chemotherapy.

Complete clinical response (CR) with tumour disappearance is not uncommon after neo-adjuvant chemotherapy (NAC) for locally advanced breast cancer, avoiding 25% mastectomies by facilitating breast-conserving procedures. We reviewed our series to understand the feasibility and utility of marking the cancer site before administering NAC. In total, 23 women (median age 47 years) with T2-4, N0-1, M0 tumours were considered unsuitable for breast conserving surgery between January 2002 and November 2003, thus received NAC following a coil placement at the core of tumour. All patients had the coil successfully inserted and no migration or infection was recorded. Eight patients (35%) had a radiological CR (rCR) including 3 (13%) with pathological CR (pCR). In total, 87% patients were managed conservatively. The insertion of a metal coil is a simple mean to provide a landmark for localisation and excision when the breast lump becomes impalpable and radiologically undetectable after the administration of NAC.

Radio-guided localization of clinically occult breast lesions (ROLL): a DGH experience.

AIM: Wire-guided localization (WGL) of clinically occult breast lesions is a well established technique. The aim of this study was to evaluate radio-guided localization (ROLL) within the breast screening service of a district general hospital. METHOD: The study group comprised 70 women who underwent ROLL under US and stereotaxis. This required an injection of Technetium-labelled colloidal albumen into the impalpable breast lesion. The women then proceeded to theatre, where localization was achieved with the use of a gamma probe. The lesion was identified by the presence of a high signal, caused by the injected isotope. The results of 70 consecutive cases in which a breast lesion was localized using ROLL were compared with the results of the latest 70 WGLs. RESULTS: All 140 lesions were successfully localized. However, the change in technique from WGL to ROLL offered significant benefits to patients. CONCLUSION: Our study demonstrated that ROLL is a practical and reliable localization technique. It can be implemented in hospital units without using valuable gamma camera time. The cost compares well with WGL. There is an improved cosmetic outcome for patients, and the very small quantity of radioactivity used is safe for both patients and staff.

Occult breast lesions: A comparison between radioguided occult lesion localisation (ROLL) vs. wire-guided lumpectomy (WGL).

Mammographic screening increases the number of impalpable breast cancers requiring surgical excision. It is important to optimise the localisation technique to remove the smallest amount of tissue, still adequately excising the lesion. The last 65 wire-guided lumpectomies (WGLs) were compared vs. the first 65 radioguided occult lesion localisations (ROLLs) performed for impalpable breast cancers. Data collection included patient's age, radiological abnormality, pre-operative core biopsy, type of primary surgery, length of localisation and excision, hospital stay, cancer size, weight and volume of the excised specimen, clearance margins. All patients were successfully localised with ROLL and WGL. Localisation time was reduced with ROLL (P<0.001). Clear margins were achieved in 83% ROLLs and 57% WGLs (P=0.001). Pathological cancer size and specimen weight were similar in both groups, although the specimen volume was slightly smaller for ROLL. A total of 74% ROLLs had excellent cosmetic outcomes and 26% good, vs. 55% excellent and 45% good in WGLs. A larger amount of normal breast tissue was excised with WGL, without achieving any better cancer clearance. ROLL provides a feasible alternative to WGL. This quick and simple technique achieves an improved rate of clear margins.

Control of an outbreak of multi-drug-resistant Acinetobacter baumannii in an intensive care unit and a surgical ward.

We describe an outbreak of multi-drug-resistant Acinetobacter baumannii (MRAB) that occurred in an intensive care unit (ICU) and a surgical ward from December 2003 to March 2004. Mapping patient movements on a timeline indicated that the outbreak was confined to these two areas. Investigation by the hospital's infection prevention service found that a possible source of spread was improper cleaning methods used on respiratory equipment. Pulsed-field gel electrophoresis analysis of available isolates indicated the presence of two distinct strains. One strain was seen in patients from the ICU and the other strain was seen in the surgical ward patients. Cleaning and environmental decontamination as well as staff education were implemented to halt further immediate spread. The deficiencies identified during the investigation were also resolved. The final outcome was the successful termination of this outbreak.

Clinical factors associated with unexpected critical care management and prolonged hospitalization after elective cervical spine surgery.

OBJECTIVES: To determine preoperative and operative factors associated with the need for unanticipated critical care management and prolonged hospitalization after cervical spine surgery. DESIGN: Retrospective, case controlled study with data collection over 5 yrs. SETTING: Intensive care unit at a Veterans Affairs hospital. PATIENTS: A total of 109 patients who underwent elective cervical decompression for degenerative disease. INTERVENTIONS: Anterior or posterior cervical spine surgery. MEASUREMENTS AND MAIN RESULTS: Data were recorded with regard to pre- and postoperative neurologic function, extent of surgery, length and cost of hospitalization and critical care, and preoperative co-morbidities. Of 109 patients, 16 (15%) required critical care management in the early postoperative phase (group I). The remainder (n = 93) represented group II. Group I had an average hospital stay of 18.5 days as compared with 6.1 days for group II (p <.001) and a cost difference of approximately $26,000. The incidence of preexisting myelopathy (69%) and the extent of decompression (2.38 levels) were greater in group I than group II (27%, p <.005; 1.67 levels, p <.01). The presence of pulmonary disease (p <.03), hypertension (p <.02), cardiovascular disease (p <.05), and diabetes mellitus (p <.002) all were associated with the need for critical care management and longer hospitalization. CONCLUSIONS: In those patients undergoing decompressive cervical surgery for degenerative disease, the following factors were linked to the need for unanticipated, postoperative critical care and longer hospitalization: multilevel decompression, preexisting myelopathy, pulmonary disease, cardiovascular disease, hypertension, and diabetes mellitus.

Post-discharge surgical wound infection surveillance in a provincial hospital: follow-up rates, validity of data and review of the literature.

BACKGROUND: Numerous studies suggest that many surgical site infections (SSI) come to light only after discharge from hospital. With increasing trends towards shorter length of stay and ambulatory day surgery, post-discharge surveillance may become necessary for all infection control programs, but the methodology has yet to be validated and standardized. The overall aim of the present study was to examine the impact of effective post-discharge SSI follow up on the overall SSI rate. METHODS: A prospective targeted surveillance programme of 1291 surgical procedures was conducted at St John of God Health Care Geelong using the standardized National Nosocomial Infections Surveillance (NNIS) METHOD: Questionnaires were sent to surgeons and the results rigorously chased up. Factors giving rise to high follow-up rates and the relationship between follow up, attrition bias and validity of data were explored using a literature search. RESULTS: A post-discharge follow-up rate of 98.7% was achieved. When the post-discharge data were included, the overall SSI rate (6.0% (95% CI: 4.7-7.4)) was more than double that in hospital (2.7% (95% CI: 1.9-3.8)). CONCLUSIONS: An effective post-discharge follow-up programme significantly increased the SSI rate. From the authors' experience and a literature survey, possible ways to achieve high follow-up rates were suggested. It was also recommended that professional and regulating bodies in Australia be encouraged to standardize methodology and set minimum follow-up rates for post-discharge SSI surveillance. Increasing use of computerized hospital database systems for automated data gathering and processing should make this more practicable.

Delayed presentation of pseudoaneurysm complicating closed humeral fracture: MR diagnosis.

Vascular injuries resulting from closed fractures of the humerus are rare. We describe two patients who developed unsuspected pseudoaneurysms following closed humeral fracture. Both patients presented with a mass, suspicious for malignancy. In each case, diagnosis was made by magnetic resonance imaging.

Infratentorial traumatic brain hemorrhage: may outcome be predicted by initial GCS?

BACKGROUND: Overall prognosis of nonpenetrating traumatic brain hemorrhage may be predicted by neurologic function days after insult. The relationship between immediate function and outcome has not been examined for infratentorial traumatic brain hemmorhage (iTBH) identified on computed tomographic (CT) scan. Given the severity of brain stem injury, it is conceivable that immediate function may be predictive. METHODS: A retrospective review of 1,500 brain injuries occurring at our institution identified 18 patients (1.2%) with iTBH on CT scan (eight brain stem, five cerebellum, five both). Demographics, supratentorial injuries, and outcome at 6 months (Glasgow Outcome Scale) were recorded. RESULTS: Initial Glasgow Coma Scale (GCS) in 11 patients was less than 5 (group I). Seven patients had GCS scores greater than or equal to 6 (group II). Nine patients in group I either died or were vegetative. In group II, one died; none were vegetative (p < 0.02). Regression analysis demonstrated a strong correlation between initial GCS and Glasgow Outcome Scale scores at 6 months for all patients (p < 0.001). CONCLUSION: We conclude that initial GCS score may be predictive of long-term outcome in patients with CT scan evidence of iTBH-a relationship to be explored further for prognostic information.

Acquired cerebral arteriovenous malformation induced by an anaplastic astrocytoma: an interesting case.

High grade gliomas foster an environment rich in angiogenic factors that promote neovascularity. We report a case of a cerebral arteriovenous malformation, which developed in the setting of a high grade astrocytoma. The patient presented with complaints of confusion and left hemiparesis. An initial cerebral angiogram was normal. Repeat angiography six weeks later demonstrated an extremely vascular lesion with arteriovenous shunting involving the right thalamus and occipital lobe. Histopathologic evaluation of open biopsy and autopsy specimens demonstrated a high grade astrocytoma in association with an arteriovenous malformation. Immunohistochemical staining with VEGF was diffusely positive. A possible role for the hyperangiogenic environment of a high grade astrocytoma resulting in the development of an arteriovenous malformation is discussed.