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1.
Phys Rev Lett ; 116(3): 031302, 2016 Jan 22.
Article in English | MEDLINE | ID: mdl-26849583

ABSTRACT

We present results from an analysis of all data taken by the BICEP2 and Keck Array cosmic microwave background (CMB) polarization experiments up to and including the 2014 observing season. This includes the first Keck Array observations at 95 GHz. The maps reach a depth of 50 nK deg in Stokes Q and U in the 150 GHz band and 127 nK deg in the 95 GHz band. We take auto- and cross-spectra between these maps and publicly available maps from WMAP and Planck at frequencies from 23 to 353 GHz. An excess over lensed ΛCDM is detected at modest significance in the 95×150 BB spectrum, and is consistent with the dust contribution expected from our previous work. No significant evidence for synchrotron emission is found in spectra such as 23×95, or for correlation between the dust and synchrotron sky patterns in spectra such as 23×353. We take the likelihood of all the spectra for a multicomponent model including lensed ΛCDM, dust, synchrotron, and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r) using priors on the frequency spectral behaviors of dust and synchrotron emission from previous analyses of WMAP and Planck data in other regions of the sky. This analysis yields an upper limit r_{0.05}<0.09 at 95% confidence, which is robust to variations explored in analysis and priors. Combining these B-mode results with the (more model-dependent) constraints from Planck analysis of CMB temperature plus baryon acoustic oscillations and other data yields a combined limit r_{0.05}<0.07 at 95% confidence. These are the strongest constraints to date on inflationary gravitational waves.

2.
Br J Cancer ; 111(5): 909-17, 2014 Aug 26.
Article in English | MEDLINE | ID: mdl-24983365

ABSTRACT

BACKGROUND: MAGE-A (melanoma-associated antigen-A) are promising targets for specific immunotherapy and their expression may be induced by the epigenetic factor BORIS. METHODS: To determine their relevance for breast cancer, we quantified the levels of MAGE-A1, -A2, -A3, -A12 and BORIS mRNA, as well as microRNAs let-7b and miR-202 in pre- and postoperative serum of 102 and 34 breast cancer patients, respectively, and in serum of 26 patients with benign breast diseases and 37 healthy women by real-time PCR. The mean follow-up time of the cancer patients was 6.2 years. RESULTS: The serum levels of MAGE-A and BORIS mRNA, as well as let-7b were significantly higher in patients with invasive carcinomas than in patients with benign breast diseases or healthy women (P<0.001), whereas the levels of miR-202 were elevated in both patient cohorts (P<0.001). In uni- and multivariate analyses, high levels of miR-202 significantly correlated with poor overall survival (P=0.0001). Transfection of breast cancer cells with synthetic microRNAs and their inhibitors showed that let-7b and miR-202 did not affect the protein expression of MAGE-A1. CONCLUSIONS: Based on their cancer-specific increase in breast cancer patients, circulating MAGE-A and BORIS mRNAs may be further explored for early detection of breast cancer and monitoring of MAGE-directed immunotherapies. Moreover, serum miR-202 is associated with prognosis.


Subject(s)
Breast Neoplasms/blood , Adult , Aged , Aged, 80 and over , Antigens, Neoplasm/blood , Antigens, Neoplasm/genetics , Breast Neoplasms/genetics , Cell Line, Tumor , DNA-Binding Proteins/blood , DNA-Binding Proteins/genetics , Female , Humans , MCF-7 Cells , Melanoma-Specific Antigens/blood , Melanoma-Specific Antigens/genetics , MicroRNAs/blood , MicroRNAs/genetics , Middle Aged , RNA/genetics
3.
ASAIO J ; 44(5): M601-5, 1998.
Article in English | MEDLINE | ID: mdl-9804505

ABSTRACT

Hypothermia has been recognized as a potential side effect of continuous hemofiltration, but the thermal energy loss within the extracorporeal circuit has not yet been quantified. The authors measured temperature decrease and thermal energy balance in vitro at different points within the extracorporeal circuit of the Acu-men (Fresenius Medical Care, Bad Homburg, Germany), a new device for continuous hemofiltration. The device employs a disposable cartridge with a pneumatic blood pump as the driving force for the blood. Furthermore, a volumetric balancing chamber is used to balance filtrate with replacement fluid. At a blood flow of 120 ml/min, a filtrate volume of 1.4 L/hr, and a replacement fluid temperature of 20 degrees C, temperature decreased from the beginning to the end of the extracorporeal circuit from 37.0 degrees C to 32.4 degrees C. This corresponds to a calculated in vitro thermal energy loss of 3,300 kJ/d. The in vivo thermal energy loss might be significantly less because of baroreceptor induced peripheral vasoconstriction, with reduced heat loss through the skin. The blood tubing contributed 26%, the hemofilter 31%, and the produced filtrate 43% to the negative thermal energy balance. Heat transmission within the volumetric balancing system of the Acu-men reduced the heat loss by 15%. Heating of replacement fluid to 30 degrees C, 37 degrees C, or 42 degrees C reduced the thermal energy loss by 22%, 48%, and 72%, respectively.


Subject(s)
Hemofiltration/instrumentation , Temperature , Equipment Design
4.
J Surg Res ; 78(1): 23-6, 1998 Jul 15.
Article in English | MEDLINE | ID: mdl-9733612

ABSTRACT

The management of patients with mammographic abnormalities is rapidly shifting from needle-localized surgical biopsy (NLB) to stereotactic core biopsy (SCB). The precise role of SCB in the management of nonpalpable breast cancer remains to be defined. The purpose of this study was to compare SCB to NLB in the diagnosis of mammographically detected breast cancer in women who underwent breast-conserving surgery. The records of all patients with nonpalpable breast cancer who underwent breast-conserving surgery from 1/1/95 to 6/1/97 were analyzed with respect to method of diagnosis, time interval from detection to diagnosis and breast-conserving surgery, volume of breast tissue excised, margin status and reexcision rate, number of surgical procedures, and total charges and costs per patient. During a 30-month period, 117 patients with nonpalpable breast cancer underwent breast-conserving surgery. The diagnosis was made by NLB in 69 patients and SCB in 48 patients. The time from detection to diagnosis and breast-conserving surgery was 1.7 +/- 0.5 and 8.1 +/- 1.2 days for SCB patients and 6. 8 +/- 1.3 and 16.9 +/- 2.3 days for NLB patients (P < 0.01). The volume of breast tissue removed was 117.9 +/- 5.6 cm3 for SCB patients versus 75.2 +/- 2.9 cm3 for NLB patients (P < 0.01). Three SCB patients (6%) had positive margins, while 38 NLB patients (55%) had positive margins (P < 0.01). Only 1 SCB patient (2%) was reexcised, while 34 NLB patients (50%) were reexcised (P < 0.01). Eighty-nine percent of SCB patients had a single surgical procedure compared to 39% of NLB patients (P < 0.001). Patients who underwent SCB had reduced total charges and total costs per patient compared to NLB patients ($11,700 +/- $554 and $3537 +/- $167 per SCB patient versus $15,654 +/- $706 and $4853 +/- $198 per NLB patient, P < 0. 0001). Stereotactic core biopsy shortens the time from detection at mammography to diagnosis and breast-conserving therapy, permits appropriate discussion of treatment alternatives, reduces the positive margin rate and reexcision rate, and may represent a significant cost savings in the management of nonpalpable breast cancer.


Subject(s)
Biopsy, Needle/economics , Breast Neoplasms/diagnosis , Breast Neoplasms/pathology , Health Care Costs , Mammography/economics , Breast Neoplasms/surgery , Cost Savings , Female , Humans , Reoperation/economics , Stereotaxic Techniques
5.
Kidney Int ; 54(1): 268-74, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9648088

ABSTRACT

BACKGROUND: We sought to design a simple machine to safely provide continuous veno-venous hemofiltration to acute renal failure patients. RESULTS: The acu-men device uses a pneumatic blood pump with tidal blood flow as the driving force. A volumetric balancing system balances the filtrate with the replacement fluid, and the blood-air interface is eliminated by replacing the conventional venous drip chamber with two air-separating membranes. The extracorporeal circuit is integrated in a disposable cartridge, which is inserted into the machine at the beginning of treatment. The priming and rinsing is done automatically. CONCLUSION: While preliminary data from an ongoing clinic trial on the efficacy of the device are encouraging, further long-term studies are necessary to evaluate its potential to decrease morbidity and mortality in acute renal failure patients.


Subject(s)
Acute Kidney Injury/therapy , Hemofiltration/instrumentation , Hemofiltration/methods , Air , Anticoagulants , Blood Coagulation , Humans , Infusion Pumps , Water-Electrolyte Balance
6.
Invest Radiol ; 32(7): 378-81, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9228602

ABSTRACT

RATIONALE AND OBJECTIVES: Use of small focal spots with low x-ray tube currents may result in very long exposure times and thus result in motion blur in magnification mammography. The authors investigated the reduction in exposure time with increasing x-ray tube kVp and the corresponding decrease in perceived visibility of low-contrast objects in phantom images. METHODS: Exposure times required to radiograph an RMI 156 phantom in a magnification geometry were measured as a function of x-ray tube kVp when operated under automatic exposure control. Magnification images of the RMI 156 phantom were obtained at x-ray tube voltages ranging from 28 to 34 kVp. Five radiology residents ranked the visibility of two borderline fibers and six borderline microcalcification specks using a 5-point scale ranging from excellent to barely visible. RESULTS: Between 28 and 34 kVp, the density of the RMI phantom images was nearly constant with a mean value of 1.32 +/- 0.04. Increasing the x-ray tube voltage from 28 kVp to 34 kVp reduced the exposure time from 1.27 seconds to 0.66 seconds. Image quality at 30 and 32 kVp was not significantly worse than that achieved at 28 kVp. Increasing the x-ray tube voltage to 34 kVp, however, resulted in a statistically significant (P < 0.001) deterioration in the relative visibility of fibers and microcalcification specks. CONCLUSIONS: Magnification mammography performed at 32 kVp will decrease exposure times significantly and result in a microcalcification and fiber visibility that is similar to that achieved at 28 kVp.


Subject(s)
Mammography/methods , Radiographic Magnification/methods , Humans , Phantoms, Imaging
7.
Biomed Tech (Berl) ; 42(3): 61-8, 1997 Mar.
Article in German | MEDLINE | ID: mdl-9181830

ABSTRACT

A new method for the ex vivo perfusion of organs from large mammals is described. Gas exchange and dialysis are carried out simultaneously with a low-flux polysulfon dialysis module. The dialysate (e.g. Tyrode solution) is aerated with a mixture of oxygen and carbon dioxide to ensure gas exchange with the blood. Dialysis is carried out in a closed thermostatically controlled system. Monitoring of ultrafiltration is maintained by continuously weighing the blood reservoir and adjusting an afferent and efferent blood pump. Initial results obtained with isolated pig kidneys demonstrate the suitability of the new method for use as a model for the replacement of animal experiments. Theoretically, clinical application in the area of in vivo regional organ perfusion may also be possible.


Subject(s)
Kidney/blood supply , Perfusion/instrumentation , Renal Dialysis/instrumentation , Animals , Carbon Dioxide/blood , Chemotherapy, Cancer, Regional Perfusion/instrumentation , Dialysis Solutions , Equipment Design , Oxygen/blood , Swine
8.
Magn Reson Imaging ; 14(6): 639-48, 1996.
Article in English | MEDLINE | ID: mdl-8897368

ABSTRACT

A polysaccharide material, TX-151, has been used together with water, NaCl, and Al powder to create a tissue equivalent gel to make a realistic, inexpensive, conveniently moldable, temporally stable tissue equivalent MRI phantom. Various phantom compositions were studied for variations in gelling time and relaxation times. Gd-DTPA added as a T1 (and T2) modifier and aluminum powder added to decrease T2 permitted phantoms to be made with a range of relaxation times comparable to human tissues. We have used this polysaccharide gel to create breast phantoms for testing breast coils and evaluating different MRI imaging sequences available for diagnosis. The breast phantoms consisted of a layer of Crisco, a good model for adipose tissue, surrounding the TX-151 gel. Some of these phantoms were created with a silicone implant encapsulated in the gel to simulate an augmented breast. More sophisticated phantoms can easily be developed by additions of other materials to this polysaccharide gel.


Subject(s)
Magnetic Resonance Imaging , Phantoms, Imaging , Female , Gels , Humans , Polysaccharides
9.
Plast Reconstr Surg ; 95(2): 364-71, 1995 Feb.
Article in English | MEDLINE | ID: mdl-7824616

ABSTRACT

Citing evidence that breast implant-related capsules resolve uneventfully, surgeons have elected to leave the capsules in place when implants are removed because capsulectomy adds both morbidity and expense to the procedure. However, recent clinical and histopathologic evidence suggests that uneventful resolution is not always the case, and several potential problems may arise from retained capsules after removal of the implant. Retained implant capsules may result in a spiculated mass suspicious for carcinoma, dense calcifications that obscure neighboring breast tissue on subsequent imaging studies, and cystic masses due to persistent serous effusion, expansile hematoma, or encapsulated silicone filled cysts. Furthermore, retained capsules are a reservoir of implant-related foreign material in the case of silicone gel-filled implants and textured implants promoting tissue ingrowth. To avoid complications from retained capsules, total capsulectomy or postoperative surveillance should be offered to patients.


Subject(s)
Breast Implants/adverse effects , Foreign-Body Reaction/etiology , Aged , Breast/pathology , Breast Diseases/diagnosis , Connective Tissue/pathology , Diagnosis, Differential , Female , Foreign-Body Reaction/diagnosis , Foreign-Body Reaction/pathology , Granulation Tissue/pathology , Humans , Middle Aged , Silicones , Time Factors
10.
Adv Exp Med Biol ; 377: 399-406, 1995.
Article in English | MEDLINE | ID: mdl-7484442

ABSTRACT

In the bovine ovary, prorenin production by theca cells is known to be regulated by LH. In the present study the aim was to evaluate whether LH-stimulated prorenin production could be further modulated by intraovarian factors in vitro. Theca cells were isolated from bovine ovaries by enzymatic dispersion, purified over Percoll gradient and cultured under serum-free conditions with LH/8Br-cAMP in the absence or presence of different steroids and growth factors and the amount of prorenin secreted into the medium was measured. None of the steroids used (androstendione, estradiol, progesterone) influenced the basal or LH-stimulated prorenin production. In contrast, cytokines and growth factors, like TNF alpha, TGF alpha, TGF beta and bFGF proved to be important regulators of prorenin synthesis. Whereas TNF alpha, TGF alpha and bFGF significantly reduced the LH- and 8Br-cAMP-induced prorenin synthesis at a site distal to cAMP formation, addition of TGF beta led to a further increase in the amount of prorenin secreted into the medium. None of the agonists had an influence on prorenin production by itself. The observed effects of cytokines and growth factors seemed to be confined to prorenin production only, since cell number, cell viability and steroidogenic response were not at all influenced by the agonists. We conclude that, although LH appears to be the primary regulator of ovarian prorenin production, several paracrine/autocrine intraovarian factors may be involved in "finely tuning" the secretion of prorenin, which is necessary for maintaining the differentiated state of the follicle.


Subject(s)
Enzyme Precursors/physiology , Ovary/physiology , Renin-Angiotensin System/physiology , Renin/physiology , Animals , Cattle , Cell Division/drug effects , Cells, Cultured , Cyclic AMP/metabolism , Estradiol/metabolism , Female , Growth Substances/pharmacology , Progesterone/metabolism , Theca Cells/metabolism
11.
Mod Pathol ; 7(6): 669-76, 1994 Aug.
Article in English | MEDLINE | ID: mdl-7991526

ABSTRACT

Clinically useful methods to identify and document the presence of foreign material in tissues surrounding breast implants are needed. Fourier transform infrared microspectroscopy is an ideal technique for examining tissue for the presence of implantable biomaterials. Because the spectroscopy is microscopically guided, the pathologist is assured that the obtained spectrum is from the region of interest in a tissue section. Scanning electron microscopy yields elemental data but cannot be used to identify compounds. Because each compound has a unique spectrum by Fourier transform infrared microspectroscopy, the spectrum obtained enables identification of the various foreign materials observed by light microscopy in tissues surrounding breast implants. Histopathology from implant capsules demonstrating a silicone gel-filled implant, a saline-filled textured implant, a polyurethane foam-covered gel-filled implant, a Dacron fixation patch, and a paraffin injection granuloma are presented with corresponding Fourier transform infrared microspectroscopy spectra.


Subject(s)
Breast Implants/adverse effects , Breast/chemistry , Dimethylpolysiloxanes/analysis , Granuloma, Foreign-Body/diagnosis , Silicones/analysis , Spectroscopy, Fourier Transform Infrared , Adult , Aged , Breast/pathology , Breast/surgery , Fat Necrosis/diagnosis , Female , Humans , Mammaplasty , Mammography , Mastectomy , Middle Aged , Paraffin/analysis , Polyethylene Terephthalates/analysis , Prosthesis Failure
12.
Mil Med ; 158(5): 356-7, 1993 May.
Article in English | MEDLINE | ID: mdl-8502404

ABSTRACT

Other than gynecomastia, bilateral breast masses in a male patient is an unusual occurrence. We present a case of fat necrosis presenting in a male veteran as bilateral palpable breast masses.


Subject(s)
Breast Neoplasms/diagnosis , Fat Necrosis/diagnosis , Aged , Diagnosis, Differential , Humans , Male , Mammography , Veterans
13.
Curr Probl Diagn Radiol ; 22(2): 39-86, 1993.
Article in English | MEDLINE | ID: mdl-8472590

ABSTRACT

Approximately 1.5 million women in the United States currently have breast implants. The majority were placed for cosmetic augmentation, but 20% were placed for reconstruction after the loss or deformity of a breast. The augmented breast is a challenge to the mammographer. Many of the palpable and mammographically detected abnormalities in these patients are related to the implant itself. Since, however, there is breast tissue present with cosmetic augmentation, the full range of fibrocystic and neoplastic conditions that can affect the breast may be seen. The presence of the implant makes imaging the breast more difficult because the implant obscures the nearby breast tissue. This paper reviews the history and evolution of various breast prostheses. The surgical approaches to placement of implants and complications associated with their use will be discussed. Examples of concomitant pathologies and a review of imaging strategies will be given.


Subject(s)
Mammaplasty/methods , Mammography , Prostheses and Implants , Breast Diseases/diagnostic imaging , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/rehabilitation , Breast Neoplasms/surgery , Contraindications , Female , Humans , Magnetic Resonance Imaging , Polyurethanes , Prostheses and Implants/adverse effects , Silicones , Tomography, X-Ray Computed , Ultrasonography, Mammary
14.
Radiographics ; 13(1): 95-118, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8426939

ABSTRACT

Recent concern regarding breast implants has emphasized the special imaging needs of the approximately 2 million American women who currently have prosthetic breast implants, including silicone gel, silicone gel with a textured silicone coating, saline, biocompatible gel, polyurethane-coated, double-lumen, and tissue expanders. Both palpable and nonpalpable breast lesions can occur in patients with implants, and these lesions must be evaluated in the same manner as in patients without implants, which presents a challenge for the mammographer. Not only is the breast tissue of a patient with implants more difficult to image, but the patient may have complications from the implants. The major complications of their use involve hematoma in the early postoperative period, infection, capsule contracture, rupture, and silicone granulomas. Familiarity with the more common types of implants, the possible complications of their use, and concurrent breast disease may help improve diagnosis in these patients.


Subject(s)
Breast Diseases/diagnostic imaging , Mammaplasty , Mammography , Prostheses and Implants , Adult , Breast/pathology , Breast Diseases/etiology , Breast Diseases/pathology , Breast Neoplasms/diagnostic imaging , Female , Humans , Mammaplasty/adverse effects , Prostheses and Implants/adverse effects
16.
Invest Radiol ; 27(10): 841-6, 1992 Oct.
Article in English | MEDLINE | ID: mdl-1399441

ABSTRACT

RATIONALE AND OBJECTIVES: Recent concern regarding possible adverse effects from silicone breast implants has increased the role of radiologists in assessing augmented breasts. The authors compare the commonly available imaging modalities in evaluating the intact silicone implant as well as free silicone in the adjacent tissue. METHODS: A contrast resolution phantom and breast of veal phantom were tested. Fat was used as a reference material. The phantoms were imaged with xeromammography, film-screen mammography, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). Proton MRI spectroscopy also was performed on fat, silicone, water, and water/gelatin samples. The consensus of two radiologists determined whether free silicone was present. RESULTS: CT and MRI provided the best images of the implant and the free silicone. Several features of MRI were useful: spin-density scans and the fast low-angle shot (FLASH) and fast imaging with steady-state precision (FISP) techniques provided excellent resolution, a consistent chemical shift artifact appeared around the silicone, and frequency selective pre-saturation techniques resulted in marked suppression of the silicone. CONCLUSION: Additional testing in a more realistic setting, breast coil design, and improvement of various MRI techniques, particularly the frequency selective pre-saturation techniques, all appear promising in evaluating breast implants, the presence of free silicone, and the adjacent tissues.


Subject(s)
Magnetic Resonance Imaging , Mammaplasty , Mammography , Models, Structural , Prostheses and Implants , Silicones , Breast/anatomy & histology , Female , Humans , Mammaplasty/adverse effects , Prostheses and Implants/adverse effects , Silicones/adverse effects , Tomography, X-Ray Computed , Ultrasonography, Mammary , Xeromammography
17.
Gynecol Oncol ; 45(2): 211-3, 1992 May.
Article in English | MEDLINE | ID: mdl-1592290

ABSTRACT

Metastatic disease to the breast is often an unexpected diagnosis in a female who presents with a breast mass. The most important factor suggesting the appropriate diagnosis is a history of cancer. Correlation of mammographic and ultrasonographic findings may also raise the possibility of a metastatic mass. A well-defined, noncalcified dense mass on film-screen mammography, which also shows low-level homogeneous echoes without posterior acoustic enhancement, suggests the diagnosis. It is important that the diagnosis be made by fine needle aspiration or excisional biopsy so as to expedite appropriate therapy.


Subject(s)
Breast Neoplasms/secondary , Carcinoma, Squamous Cell/secondary , Uterine Cervical Neoplasms/pathology , Biopsy , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Carcinoma, Squamous Cell/diagnostic imaging , Carcinoma, Squamous Cell/pathology , Female , Humans , Mammography , Middle Aged , Ultrasonography
18.
Plast Reconstr Surg ; 87(4): 703-8, 1991 Apr.
Article in English | MEDLINE | ID: mdl-2008468

ABSTRACT

The assessment of implant capsular contracture has been imprecise and vulnerable to observer bias. Attempts to measure capsules with instruments that measure implant deformability are influenced by surrounding breast tissue, subcutaneous fat, and skin. Xeromammography, B-mode ultrasound, and CT were employed in an effort to provide a noninvasive and accurate method of capsule assessment. Through two study phases, implants were placed bilaterally in a total of 21 rabbits. At 4 months, animals underwent radiologic assessment and were then sacrificed for direct implant capsule measurements. Mammographic measurements, more than ultrasound-derived measurements, strongly correlated with laboratory measures of capsular dimensions and deformability. Cross-table lateral mammographic views were more informative than traditional views, providing measures of diameter and height that both strongly correlated with laboratory measurements. CT is theoretically the most accurate method to assess contracture, but it is impractical because of expense and time requirements. The results indicate that radiologic assessment, in particular by xeromammography, of implant capsules is accurate, practical, and noninvasive. Mammography strongly correlates with laboratory measures of implant capsular contracture and therefore could be used in the clinical setting to assess capsular contracture.


Subject(s)
Contracture/diagnosis , Prostheses and Implants , Animals , Contracture/diagnostic imaging , Rabbits , Tomography, X-Ray Computed , Ultrasonography , Xeromammography
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