Hepatic visceral larva migrans: A radiological case report

Visceral larva migrans (VLM) occurs due to migration of the second stage of larvae of nematodes through human viscera. It is an underdiagnosed entity which commonly affects the liver as eosinophilic abscesses and appears as coalescing, conglomerated cavities on imaging. This case report details the sonographic and CT features of an 8 year old female patient with right upper quadrant pain and peripheral eosinophilia on laboratory reports, diagnosed as a case of VLM on biopsy. Imaging of VLM shows overlap with neoplastic lesions and other infective pathologies hence this case aims to highlight the clinical, laboratory, and radiological features to help narrow the differential diagnosis.

Leriche syndrome: Clinical and diagnostic approach of a rare infrarenal aortoiliac occlusive disease

Leriche syndrome is an aortoiliac occlusive arterial disease comprising decreased peripheral pulses, claudication, and erectile dysfunction. We present a case of a 60-year-old male with abdominal pain and hematochezia who was diagnosed with hemorrhoids. The patient also had associated leg cramps on both sides and lower limb weakness. Further evaluation of the patient with imaging revealed occlusion of the distal descending abdominal aorta below the level of renal arteries and the iliac arteries. An incidental finding of Leriche syndrome was evident. This case report contributes to the current literature when any patient with abdominal pain and bilateral lower limb weakness, Leriche syndrome should be considered to avoid complications as it has high morbidity and mortality.

Liver abscess with extension into the Inferior Vena Cava: Case series of a rare complication

Liver abscess is a common disease, however, it is a rare cause of venous thrombosis. The incidence of amoebic and pyogenic liver abscess in developing countries is high, however, the occurrence of inferior vena cava thrombosis secondary to liver abscess is a very rare and life-threatening complication. Computed tomography (CT) scan is an ideal investigation tool for diagnosing the various complications associated with liver abscess. Here we describe 3 cases of liver abscess in patients who developed a rare vascular complication of inferior vena cava. Liver abscesses should be considered as a rare cause of IVC thrombosis in the correct clinical context. All the patients were managed with ultrasound-guided pigtail insertion and antimicrobial agents.

Primary anorectal amelanotic melanoma with liver, lungs and lymph nodal metastases

Anorectal melanoma (ARM) is an exceedingly rare and very aggressive malignancy. It originates from the melanocytic cells in the anorectal mucosa, which produces melanin. Other mucosal melanomas commonly found in the mucosa of the oral cavity, vulvovaginal, pharynx and urinary tract. Patients usually present with bleeding per rectum, perianal pain and difficulty in defaecation. Distinction of primary anorectal melanoma from other tumours of this region is difficult because of the lack of common imaging features. MRI is the modality of choice for its better tissue characterisation and resolution. There is no standard treatment protocol available mainly due to scarcity of data. Surgery is the mainstay therapy. Herein we present a case of a male patient in his 30s who presented with rectal bleeding and perianal pain. Haematological analysis revealed normocytic normochromic anaemia. MRI detected a mass lesion in the anorectal region. Contrast enhanced CT revealed multiple metastases in the liver, lungs, periportal, mesorectal and inguinal lymph nodes. The diagnosis of the ulcerated anorectal melanoma was established on histopathological examination. The patient underwent abdominoperineal resection (APR) followed by chemotherapy. Afterward the patient presented to the emergency room with respiratory distress for which he was on ventilator support. Sadly, the patient died after four days.

Primary hepatic epithelioid hemangioendothelioma masquerading as metastases: A rare case report

Epithelioid hemangioendothelioma (EHE) of the liver is an extremely rare malignant tumor of vascular origin, representing less than 1 % of all vascular tumors. Nearly 260 cases have been reported in English literature. Radiologically it is seen as multifocal lesions. It can be seen at different sites like lungs, bones, lymph nodes, breasts, and soft tissue. Often it is misdiagnosed with metastases, cholangiocarcinoma, or angiosarcoma. No definite treatment protocol is available due to its rarity, however, these malignancies are treated by radical resection of the tumor or liver transplant and/or chemotherapy. Here we present a primary hepatic epithelioid hemangioendothelioma (HEHE) which was mimicking metastases in a 42-year-old male who was treated with chemotherapy and radiotherapy. Sadly the patient expired after 1 year of complete course of treatment. Imaging features can help to improve the diagnostic accuracy of this tumor.

Late presentation of Swyer syndrome: A case report

Swyer syndrome-a rare syndrome associated with complete gonadal dysgenesis-is seen in phenotypically female patients with 46-XY karyotype. They usually present with primary amenorrhea or delayed puberty. The dysgenetic gonad, which is nonfunctional, is prone to undergo malignant transformation such as dysgerminoma, gonadoblastoma, etc. Timely diagnosis helps in deciding appropriate management strategies for the patient such as hormone replacement therapy and gonadectomy. Thirty-year-old patient with a female external phenotype presented to us with complaints of primary amenorrhea. There was no similar family history of infertility, amenorrhea, abnormal external genitalia development, or cryptorchidism. On physical examination, the breast development of the patient was within normal limits for her age (Tanner stage 5), however; the axillary and pubic hair were underdeveloped (Tanner stage 2). Pelvic and inguinal ultrasound of the patient showed a hypoplastic uterus along with a cystic structure in left pelvis with no evidence of any testes like structure in inguinal region, pelvis, or abdomen. The patient was further evaluated with MRI of pelvis which confirmed the ultrasound findings of a hypoplastic uterus along with a dysplastic cystic left gonad with no evidence of any ovary or ovary-like structure/testes/testes-like structure in abdomen. Possibility of complete gonadal dysgenesis was given which was further confirmed by the hormonal assay that showed hypergonadotropic-hypogonadism with raised serum follicular stimulating hormone (FSH) and serum luteinizing hormone (LH) levels and a low estradiol, low testosterone, and low anti-Mullerian hormone (AMH) levels. Serum prolactin (PRL), serum thyroid stimulating hormone (TSH), and serum beta human chorionic gonadotropin (beta hCG) levels were within normal range. The cytogenetic report of the patient showed a 46-XY karyotype confirming our diagnosis. The patient was advised to undergo prophylactic gonadectomy for the left gonad. Swyer syndrome is a rare disorder of sexual development which needs vigorous clinical, laboratory, and radiological evaluation. Ultrasound is the primary investigation of choice whereas MRI is used as a problem-solving tool in localizing the streak gonads. Early diagnosis is crucial in these patients since prophylactic gonadectomy reduces the risk of developing germ cell tumor.

Vanishing acardiac twin with TRAP syndrome: A case report

Acardiac twin is a rare complication of monochorionic twin pregnancy. We present case of a 24 years-old primigravida with monochorionic pregnancy having an amorphous acardiac twin diagnosed during routine first trimester ultrasound scan. She was managed expectantly since there were no signs of hemodynamic compromise in the normal twin with close ultrasound fetal surveillance using gray scale and color Doppler ultrasound. Spontaneous regression of vascularity with reduced size of the acardiac twin was seen subsequently.

Primary monophasic synovial sarcoma of the lung: Rare case report

Primary monophasic synovial sarcoma of the lung is an extremely rare malignant mesenchymal tumor that can develop at any anatomic site. Synovial sarcoma is considered a high grade tumor with a poor prognosis. Metastatic pulmonary sarcoma is much more common. Hence primary lesion elsewhere in the body needs exclusion. No clinical or radiological features are specific for pulmonary sarcoma, often it is confused with bronchogenic carcinoma. Therefore biopsy is needed to establish the diagnosis of this rare tumor. We hereby present two cases of histologically proven primary monophasic synovial sarcoma of lung. The imaging features of this rare disease is reviewed.

Primary squamous cell carcinoma of pancreas in a patient with chronic pancreatitis: A rare case report

Primary squamous cell carcinoma of pancreas is a rare malignant neoplasm. It has been reported as case reports only, hence clinical information is limited. Here, we present a case of primary squamous cell carcinoma of pancreas in a 47-year-old female with a background history of chronic pancreatitis. Patient was treated with systemic chemotherapy; however, she did not respond to the treatment protocol. Follow-up CT scan showed increase in the size and extension of the lesion. It is an aggressive tumor and does not respond well to chemotherapy or radiotherapy.

Macrodystrophia lipomatosa of finger-A rare case report

Macrodystrophia lipomatosa is a rare form of nonhereditary congenital localized gigantism involving upper and lower limbs and is characterized by overgrowth of all the mesenchymal elements predominantly fibro-adipose component, in the distribution of a particular nerve, usually median nerve. It usually presents with progressive painless overgrowth of the involved limb, toe, or digit and is associated with macrodactyly. It might cause limitation of the movement of the involved part. Imaging has an important role in diagnosing this condition and differentiating it from malignant mimics. Imaging findings include hypertrophy of the mesenchymal elements of the involved digits and/or limbs predominantly fibro adipose component with associated overgrowth of the phalanges. In this case report, we present a case of unilateral involvement of index finger and thumb with associated macrodactyly.

Leg muscle involvement in polyarteritis nodosa (limited form)-A rare case report

Polyarteritis nodosa is a necrotizing arteritis involving small and medium vessels. Polyarteritis nodosa can have variable presentations depending upon the organ involved. It can either present as a diffuse disease or a limited form confined to a particular organ. Isolated muscular involvement in this disease is rare, which may present as myalgia, nonspecific fever, weight loss or even as claudication. The imaging pattern on ultrasound and MRI can help diagnose this condition in the background of clinical history and muscle biopsy is confirmatory. We present a case of 15 years old boy who presented with fever, weight loss, myalgia in leg region. MRI and ultrasound examination showed perivascular inflammation in calf muscles with a characteristic "cotton wool" pattern of enhancement on contrast study.

Enhanced Crystallinity of Covalent Organic Frameworks Formed Under Physical Confinement by Exfoliated Graphene

The polymerization of 1,4-benzenediboronic acid (BDBA) on mica to form a covalent organic framework (COF-1) reveals a dramatic increase in crystallinity when physically confined by exfoliated graphene. COF-1 domains formed under graphene confinement are highly geometric in shape and on the order of square micrometers in size, while outside of the exfoliated flakes, the COF-1 does not exhibit long-range mesoscale structural order, according to atomic force microscopy imaging. Micro-Fourier transform infrared spectroscopy confirms the presence of COF-1 both outside and underneath the exfoliated graphene flakes, and density functional theory calculations predict that higher mobility and self-assembly are not causes of this higher degree of crystallinity for the confined COF-1 domains. The most likely origin of the confined COF-1's substantial increase in crystallinity is from enhanced dynamic covalent crystallization due to the water confined beneath the graphene flake.

Imaging Features of Intramedullary Spinal Cord Lesions with Histopathological Correlation

Purpose Most of the intramedullary spinal cord lesions have a component of insidious myelopathic changes at the time of diagnosis. Among the spinal cord lesions, intramedullary neoplasms are rare (25%). They represent 4 to 10% of all central nervous system tumors. But due to involvement of tracts, they are associated with significant neurological symptoms. Their imaging features can help early diagnosis and predict prognosis. We aim to narrow down differential diagnoses of intramedullary lesions based on imaging findings.

Materials and Methods This retrospective study included 40 patients as a sample that underwent magnetic resonance imaging spine at our institution (on 3T machine). Patient population had varied clinical complaints, ranging from headache, nausea, vomiting, motor weakness, bladder and bowel involvement, progressive paraparesis to paraplegia. Lesions were evaluated site, size, margin, associated cysts, signal intensity, enhancement, and associated syringohydromyelia.

Results This study obtained majority of the lesions to be ependymoma (15) and astrocytoma (11), followed by infection (4), hemangioblastoma (3), and metastasis (2). Five patients were either lost to follow-up or not operated on.

Conclusion Most of the intramedullary lesions were malignant and were showing postcontrast enhancement. Ependymomas were more frequently present in cervical region, central in location with well-defined margins and focal postcontrast enhancement. Among the total of 15 ependymomas, three cases were associated with neurofibromatosis-2. Ependymomas were more frequently associated with syringohydromyelia and peripheral hemorrhage (cap sign). Astrocytoma was more frequently seen in children, thoracic and eccentric in location with ill-defined margins. Enhancement in astrocytoma was dependent on the grade of tumor. Metastasis was a differential, with imaging characteristics dependent on type of primary. Intramedullary granuloma due to infection can also be confusing mimics of neoplasm. High-velocity signal loss due to flow voids is seen in the hemangioblastomas.

Evaluation of the relationship between blood cell parameters and vascular calcification in dialysis-dependent end-stage renal disease patients

Coronary artery calcification is an acceptable tool for cardiovascular risk assessment in end-stage renal disease (ESRD) population. We aimed to identify the association and predictive value of components of blood cell parameters with coronary and thoracic aorta vascular calcification (VC) in ESRD population on dialysis. All ESRD patients receiving hemodialysis or peritoneal dialysis aged between 18 and 60 years were included in the study. Exclusion criteria comprised patients with active infection or inflammatory disease, autoimmune disease, congestive heart failure, angina pectoris and/or documented coronary artery disease, thyroid disease, and hepatic dysfunction. Agatston scoring was used for the evaluation of coronary aorta calcification (CAC) score (CACS) and thoracic aorta calcification (TAC) score (TACS). Compared to participants with no VC, those who had VC were statistically significantly older (P <0.001) and had higher neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) (P = 0.02 and <0.001, respectively). On multivariate logistic regression analysis, increasing age (P = 0.00) and higher PLR (P = 0.04) were associated with an increased likelihood of exhibiting VC (CAC or TAC). There was a positive correlation between CACS and age (rs = 0.495, P = 0.00). A statistically significant positive correlation existed between TACS and age (rs = 0.516, P = 0.00). Similarly, a positive correlation was found between NLR, PLR, and TACS (rs = 0.334, P = 0.001, and rs = 0.438, P = 0.00, respectively). On multivariate linear regression analysis, increased age and red cell distribution width were found to be significant predictors of log(n) TACS. PLR of 135 gave a sensitivity of 80% and a specificity of 50% for predicting VC. Being a cost-effective and easily available investigation, the utilization of the correlation of NLR and PLR with CAC and TAC appears promising, particularly in the age group of 30-60 years.

Crossed beam energy transfer between optically smoothed laser beams in inhomogeneous plasmas

Crossed beam energy transfer, CBET, in high-intensity laser-plasma interaction is investigated for the case of optically smoothed laser beams. In the two approaches to laser-driven inertial confinement fusion experiments, the direct-drive and the indirect-drive, CBET is of great importance because it governs the coupling of laser energy to the plasma. We use the two-dimensional wave-coupling code Harmony to simulate the transfer between two laser beams with speckle structure that overlap in a plasma with an inhomogeneous flow profile. We compare the CBET dynamics for laser beams with spatial incoherence and with spatio-temporal incoherence; in particular we apply the smoothing techniques using random phase plates (RPPs) and smoothing by spectral dispersion (SSD), respectively. It is found that for laser beams (wavelength λ₀) with intensities (I_L) above I_L ∼ 2 × 10¹⁵ W cm^-2(λ₀/0.35 µm)^-2(T_e/keV), both the so-called plasma-induced smoothing as well as self-focusing in intense laser speckles induce temporal incoherence; the latter affects the CBET and the angular distribution of the light transmitted behind the zone of beam overlap. For RPP-smoothed incident beams, the resulting band width of the transmitted light can already be of the same order as the effective band width of the SSD available at major laser facilities. We examine the conditions when spatio-temporal smoothing techniques become efficient for CBET. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 1)'.

Lymph Nodal Metastatic Pattern in Carcinoma Gallbladder with Multidetector Computed Tomography: An Institutional Experience

Objective This work aimed to study the distribution of lymph nodal metastatic pattern in carcinoma gallbladder with multidetector computed tomography (CT).

Materials and Methods A retrospective observational study was conducted including 80 patients with carcinoma gallbladder who underwent triple-phase CT angiography or single-phase contrast-enhanced CT scan of the abdomen between January 2019 and November 2019.

Results In our study, 75 (93.7%) out of 80 cases showed metastasis to lymph nodes, with distribution as follows: periportal (69), peripancreatic (62), and aortocaval (47). The most common involved combination included all three lymph nodal groups (periportal, peripancreatic, and aortocaval), involving 40 (50%) cases. The combination of only periportal and peripancreatic lymph nodes was seen in 17 (21%) cases. Isolated periportal lymph nodes were seen in eight cases (10%) cases. The combination of only periportal and aortocaval lymph nodes was seen in four (5%) cases. Isolated peripancreatic lymph nodes were seen in three (3.7%) cases. The combination of periportal and aortocaval was seen in four (5%) cases followed by peripancreatic and aortocaval lymph nodes that was seen in two (2.5%) cases. Isolated aortocaval lymph nodes were seen in one (1.2%) case.

Conclusion Periportal lymph nodes were the single most commonly involved station followed by peripancreatic and aortocaval lymph nodes. The combination of periportal, peripancreatic, and aortocaval lymph nodes was seen most commonly. The second most commonly involved combination was found to be periportal and peripancreatic lymph nodes followed by isolated periportal lymph nodes.

Assessment of Celiac Axis and Hepatic Artery Variations in Hepatobiliary and Pancreatic Malignancy with Multidetector Computed Tomography Angiography

Introduction Delineation of variant anatomy in celiac trunk and superior mesenteric artery including its origin and branching pattern and variations in branching pattern of hepatic artery in patients of hepatopancreaticobiliary malignancy with the use of mutidetector CT (computed tomography) angiograpgy was performed.

Materials and Methods All CT examinations were performed on a 64-multidetector computed tomography (MDCT) scanner. Technical features of multislice computed tomography (MSCT) are as follows: 64 mm × 1 mm collimation, minimum slice thickness of 0.625, gantry rotation time of 320 ms, 120 kV, and 320 mAs. CT angiography was performed with intravenous (IV) administration of nonionic contrast material, that is, iodixanol (Visipaque). The contrast medium and saline solution were injected with a Medrad power injector at 3 mL/sec through an 18-gauge plastic intravenous catheter placed in an antecubital vein in most of the cases. Contrast medium volumes varied between 100 and 150 mL at 1.5 mL/kg. Images were obtained in triphasic pattern at arterial (20–30 seconds), portal (60–70 seconds), and equilibrium (at 3 minutes) phases.

Results Five types of celiac axis anatomic variations and nine type of variants in celiac axis branching was found in the study sample of 124 patients. Classical celiac axis anatomy was seen in 92.7% of the cases, while the five types of variation in branching were found in nine patients. Majority of cases showed pattern I (59.6%) followed by patterns V (12.1%), II (9.7%), and III (8.9%). There were three (2.4%) cases each showing pattern VIII and AA, and two (1.6%) cases each showing patterns IV and VI, respectively. There was one (0.8%) case each showing pattern VII and IX. A total of three (2.4%) cases showed right hepatic artery arising from celiac axis.

Conclusion We conclude that most common pattern of celiac axis and superior mesenteric artery (SMA) branching is classical pattern (92.7%) which is in concordance with literature. Type-I pattern of hepatic artery branching was most common (59.6%), similar to that documented in literature. Although the most common variation in our study is type V (12.1%), followed by types II (9.7%) and III (8.9%), the most common variation in most of the literature was found to be type III. CT angiography hence is an excellent diagnostic modality for depiction of arterial anatomic variations and provides a roadmap for surgical treatment.

Betatron radiation and emittance growth in plasma wakefield accelerators

Beam-driven plasma wakefield acceleration (PWFA) has demonstrated significant progress during the past two decades of research. The new Facility for Advanced Accelerator Experimental Tests (FACET) II, currently under construction, will provide 10 GeV electron beams with unprecedented parameters for the next generation of PWFA experiments. In the context of the FACET II facility, we present simulation results on expected betatron radiation and its potential application to diagnose emittance preservation and hosing instability in the upcoming PWFA experiments. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

Producing multi-coloured bunches through beam-induced ionization injection in plasma wakefield accelerator

This paper discusses the properties of electron beams formed in plasma wakefield accelerators through ionization injection. In particular, the potential for generating a beam composed of co-located multi-colour beamlets is demonstrated in the case where the ionization is initiated by the evolving charge field of the drive beam itself. The physics of the processes of ionization and injection are explored through OSIRIS simulations. Experimental evidence showing similar features are presented from the data obtained in the E217 experiment at the FACET facility of the SLAC National Laboratory. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

Abstract P2-06-02: Development of a first-in-class small molecule inhibitor (EC359) targeting oncogenic LIF/LIFR signaling for the treatment of triple negative breast cancer

Background: Leukemia inhibitory factor (LIF) and its receptor LIFR are over-expressed in multiple solid tumors and play a key role in tumor growth, progression, and resistance to standard anti-cancer treatments. Triple-negative breast cancer (TNBC) lacks targeted therapies and represents a disproportional share of breast cancer (BCa) mortality. TNBC exhibits autocrine stimulation of the LIF/LIFR axis and overexpression of LIF is associated with poorer relapse-free survival in BCa patients. LIF signaling also promotes maintenance of stem cells. Therefore, targeting the LIF/LIFR axis may have therapeutic utility in TNBC.

Methods: We rationally designed a small organic molecule (EC359) that emulates the LIF/LIFR binding site and functions as a LIFR inhibitor from a library of compounds. In silico docking studies were used to identify the putative interaction of the EC359 and LIF/LIFR complex. Direct binding of EC359 to LIFR was confirmed using surface plasmon resonance (SPR) and microscale thermophoresis technique (MST) assays. In vitro activity was tested using Cell-Titer Glo, MTT, invasion, and apoptosis assays. Mechanistic studies were conducted using Western blot, reporter gene assays, and RNA-seq analysis. Xenograft, patient-derived xenograft (PDX), and patient-derived explant (PDEX) models were used for preclinical evaluation and toxicity.

Results: Molecular docking studies showed that EC359 interacts at the LIF/LIFR binding interface. SPR and MST studies confirmed direct interaction of EC359 to LIFR. EC359 reduced the growth of TNBC cells with high potency (IC50 50-100nM) and promoted apoptosis. Further, EC359 treatment reduced invasion and stemness of TNBC cells. EC359 activity is dependent on the expression levels of LIFR and showed little or no activity on TNBC cells that have low levels of LIFR or ER+ve BCa cells. Further, EC359 significantly reduced the viability of cisplatin and taxane-resistant TNBC cells and enhanced the efficacy of HDAC inhibitors. Mechanistic and biochemical studies showed that EC359 interacts with LIFR and effectively blocking LIF/LIFR interactions. EC359 also blocked LIFR interactions with other LIFR ligands such as oncostatin M, ciliary neurotrophic factor, and cardiotrophin-1. EC359 treatment attenuated the activation of LIF/LIFR driven pathways including STAT3, mTOR, AKT, and MAPK. RNA-seq analysis identified regulation of apoptosis as one of the important pathway modulated by EC359. In TNBC xenograft and PDX assays, EC359 significantly reduced tumor progression. Further, using human primary BCa PDEX cultures, we demonstrated that EC359 has the potential to substantially reduce the proliferation of human BCa. Pharmacologically, EC359 exhibited high oral bioavailability and long half-life with a wide therapeutic window.

Conclusions: EC359 is a novel targeted therapeutic agent that inhibits LIF/LIFR oncogenic signaling in TNBC via a unique mechanism of action. EC359 has the distinct pharmacologic advantages of oral bioavailability, in vivo stability, and is associated with minimal systemic side effects. (DOD BCRP grant #BC170312)

Citation Format: Viswanadhapalli S, Luo Y, Sareddy GR, Santhamma B, Zhou M, Li M, Pratap UP, Altwegg KA, Li X, Srinivasan U, Ma S, Chang A, Riveros AC, Zhang KY, Dileep KV, Pan X, Murali R, Bajda M, Raj G, Brenner A, Manthati V, Rao M, Tekmal RR, Nair HB, Nickisch KJ, Vadlamudi RK. Development of a first-in-class small molecule inhibitor (EC359) targeting oncogenic LIF/LIFR signaling for the treatment of triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-06-02.

An ultra-high gain and efficient amplifier based on Raman amplification in plasma

Raman amplification arising from the excitation of a density echelon in plasma could lead to amplifiers that significantly exceed current power limits of conventional laser media. Here we show that 1-100 J pump pulses can amplify picojoule seed pulses to nearly joule level. The extremely high gain also leads to significant amplification of backscattered radiation from "noise", arising from stochastic plasma fluctuations that competes with externally injected seed pulses, which are amplified to similar levels at the highest pump energies. The pump energy is scattered into the seed at an oblique angle with 14 J sr-1, and net gains of more than eight orders of magnitude. The maximum gain coefficient, of 180 cm-1, exceeds high-power solid-state amplifying media by orders of magnitude. The observation of a minimum of 640 J sr-1 directly backscattered from noise, corresponding to ≈10% of the pump energy in the observation solid angle, implies potential overall efficiencies greater than 10%.

Impact of Laser Beam Speckle Structure on Crossed Beam Energy Transfer via Beam Deflections and Ponderomotive Self-Focusing

The role of laser speckle structure (hot spots) and its ponderomotive self-focusing (PSF), in crossed beam energy transfer (CBET), of smoothed laser beams is investigated in an inhomogeneous expanding plasma. Numerical simulations using the code harmony in two spatial dimensions, demonstrate how self-focusing of laser hot spots in crossed beams can significantly affect the transfer of energy from one beam to the other in addition to the stimulated Brillouin scattering (SBS) process. It is shown that for sufficiently intense laser beams, when the laser hot spots exceed the criterion for self-focusing in a plasma with flow, the angular spread of transmitted light beams increases considerably with the intensity, which arises in particular, in expanding plasma where significant beam deflection is observed. It is shown for the first time that besides SBS, the contribution of speckle structure, PSF, and deflections of the intense hot spots in multiple speckle beams to CBET, therefore matters.

Characterization of glioma-cells derived from human polyomavirus-induced brain-tumors in hamsters

Intracerebral injection of human polyomavirus, JCV, into neonatal hamsters causes tumors of,glial origin. HJC is an established cell Line derived from a JCV-induced mixed hamster brain tumor with astrocytic and ependymal components. Flow cytometric and immunohistochemical analysis of HJC suggests that it is comprised of a mixed population of cells all of which contain the JCV early protein, T-antigen, in the nuclei. Five individual clonal lines, called HJC-15a to HJC-15e, were isolated by limiting dilution and were found to exhibit distinct morphological characteristics with 25-30% variation in their sizes. It was evident that each clone has unique growth rates, doubling times, and cell cycle parameters with different G(1), S, and G(2) phase times. All clonal cells showed the presence of the JCV early protein in the nucleus. Of interest was the observation from immunoprecipitation and Western analysis indicating qualitative and quantitative differences in the T-antigen isoforms produced in these cells. Similar to the parental clone, HJC-15b produced two distinct forms of JCV T-antigen isoforms, 88 kDa and 92 kDa proteins. In addition, HJC-15c was able to produce a 23-25 kDa protein which was recognized by anti-T-antigen antibody. The activity of cyclin-dependent kinases, in particular cdc2, was higher in HJC-15c than in the other cell lines. The data presented herein indicates that glioblastomas induced by viral T-antigen expression are composed of a multitude of distinct cells that possess a variety of different characteristics.

Low emittance, high brilliance relativistic electron beams from a laser-plasma accelerator

Progress in laser wakefield accelerators indicates their suitability as a driver of compact free-electron lasers (FELs). High brightness is defined by the normalized transverse emittance, which should be less than 1π mm mrad for an x-ray FEL. We report high-resolution measurements of the emittance of 125 MeV, monoenergetic beams from a wakefield accelerator. An emittance as low as 1.1±0.1π mm mrad is measured using a pepper-pot mask. This sets an upper limit on the emittance, which is comparable with conventional linear accelerators. A peak transverse brightness of 5×10¹⁵ A m⁻¹ rad⁻¹ makes it suitable for compact XUV FELs.

Adverse cardiac events after surgery: assessing risk in a veteran population

OBJECTIVE

To establish rates of and risk factors for cardiac complications after noncardiac surgery in veterans.

DESIGN

Prospective cohort study.

SETTING

A large urban veterans affairs hospital.

PARTICIPANTS

One thousand patients with known or suspected cardiac problems undergoing 1,121 noncardiac procedures.

MEASUREMENTS

Patients were assessed preoperatively for important clinical variables. Postoperative evaluation was done by an assessor blinded to preoperative status with a daily physical examination, electrocardiogram, and creatine kinase with MB fraction until postoperative day 6, day of discharge, death, or reoperation (whichever occurred earliest). Serial electrocardiograms, enzymes, and chest radiographs were obtained as indicated. Severe cardiac complications included cardiac death, cardiac arrest, myocardial infarction, ventricular tachycardia, and fibrillation and pulmonary edema. Serious cardiac complications included the above, heart failure, and unstable angina.

MAIN RESULTS

Severe and serious complications were seen in 24% and 32% of aortic, 8.3% and 10% of carotid, 11.8% and 14.7% of peripheral vascular, 9.0% and 13.1% of intraabdominal/intrathoracic, 2.9% and 3.3% of intermediate-risk (head and neck and major orthopedic procedures), and 0.27% and 1.1% of low-risk procedures respectively. The five associated patient-specific risk factors identified by logistic regression are: myocardial infarction < 6 months (odds ratio [OR], 4.5; 95% confidence interval [CI], 1.9 to 12.9), emergency surgery (OR, 2.6; 95% CI, 1.2 to 5.6), myocardial infarction > 6 months (OR, 2.2; 95% CI, 1.4 to 3.5), heart failure ever (OR, 1.9; 95% CI, 1.2 to 3.0), and rhythm other than sinus (OR, 1.7; 95% CI, 0.9 to 3.2). Inclusion of the planned operative procedure significantly improves the predictive ability of our risk model.

CONCLUSIONS

Five patient-specific risk factors are associated with high risk for cardiac complications in the perioperative period of noncardiac surgery in veterans. Inclusion of the operative procedure significantly improves the predictive ability of the risk model. Overall cardiac complication rates (pretest probabilities) are established for these patients. A simple nomogram is presented for calculation of post-test probabilities by incorporating the operative procedure.

Influence of body weight on response to subcutaneous vitamin K administration in over-anticoagulated patients

PURPOSE

To determine the influence of body weight on the international normalized ratio (INR) response to a fixed dose of vitamin K in overanticoagulated patients.

METHODS

Retrospective review of records of patients who received 1 mg of vitamin K subcutaneously to correct excessive INR. Dose of vitamin K in milligrams per kilograms plotted against change in INR in 24 hours.

RESULTS

Fifteen patients were identified who met all inclusion criteria. Linear regression analysis plotted INR response at 24 hours versus dose of vitamin K adjusted for body weight. Pearson's product moment correlation (R = 0.85) indicated a significant relationship between INR response at 24 hours to an adjusted body weight dose of subcutaneous vitamin K (P = 0.0000523). A strong correlation (r = 0.69) also existed between INR response at 24 hours and the actual body weight dose of subcutaneous vitamin K (P = 0.004).

CONCLUSIONS

In overanticoagulated patients, variability in response to vitamin K may be explained by variability in body weight. Dosing vitamin K according to body weight may result in a more predictable INR response.

Granulocytic sarcoma of the head and neck: a case report

A rare case of granulocytic sarcoma of the head and neck region is presented to highlight its unusual clinical presentation and the difficulties encountered in its diagnosis. The risk factors, pathological findings, and treatment modalities are discussed to make head and neck surgeons aware of this condition, which can have a fatal outcome as happened in our case.

Time course of reversal of anticoagulant effect of warfarin by intravenous and subcutaneous phytonadione

BACKGROUND

Excessive anticoagulation increases the risk of hemorrhagic complications associated with oral anticoagulant therapy. Oral or parenteral phytonadione is used to reverse excessive anticoagulation. Intravenous (IV) phytonadione, while effective, is associated with a small risk of serious anaphylactic reactions. Subcutaneous (SC) administration is safer, but there is little information on its relative efficacy in small doses.

METHODS

Twenty-two patients with asymptomatic prolongation of prothrombin time were prospectively randomized and treated with 1 mg of phytonadione IV or 1 mg SC. Prothrombin time was measured at baseline and at 8 and 24 hours after phytonadione administration and expressed as international normalized ratio (INR).

RESULTS

Mean INR at baseline was 8.0 and 8.5 in the IV and SC groups, respectively (P = .70). At 8 hours, mean INR was 4.6 in the IV group and 8.0 in the SC group (P = .006), and at 24 hours, mean INR was 3.1 in the IV group and 5.0 in the SC group (P = .009). Mean decrease in INR 8 hours after administration of phytonadione was 3.4 in the IV group and 0.4 in the SC group (P = .02), and mean decrease in INR after 24 hours was 4.9 in the IV group and 3.4 in the SC group (P = .18).

CONCLUSIONS

For patients who are excessively anticoagulated with warfarin, small doses of SC phytonadione may not correct the INR as rapidly or as effectively as when administered IV. Higher doses must be considered for more rapid and complete reversal of anticoagulation by the SC route.

Safety of intramuscular influenza immunization among patients receiving long-term warfarin anticoagulation therapy

BACKGROUND

The effect of influenza vaccine on the prothrombin time (PT) among patients taking warfarin is unclear, as previous studies have shown conflicting results and the clinical significance of such a purported effect is uncertain. Moreover, to our knowledge, there are no data confirming the safety of intramuscular injections in patients receiving anticoagulant therapy with regard to possible local hematoma formation. We measured the effect of influenza vaccine on the PT among patients receiving long-term warfarin sodium therapy and evaluated the safety of intramuscular injections among them.

METHODS

Forty-one adult patients who were receiving anticoagulant therapy were given 0.5 mL of influenza vaccine intramuscularly. Prothrombin time and arm girth were measured at baseline and on days 3, 7, and 14 after immunization. Local pain and tenderness were assessed on a five-point scale. Patients and study nurses were blinded to all prior measurements. Differences between baseline PT and that at each subsequent visit and the maximal change in arm circumference from baseline were calculated for each patient. Mean, range, and 95% confidence intervals were calculated for the entire group.

RESULTS

There was no statistically significant change in PT between baseline and days 3, 7, and 14 after vaccination, and no significant change in arm circumference was noted. There were no clinically detectable local complications after intramuscular injection and no major or minor bleeding episodes after influenza vaccination.

CONCLUSIONS

Influenza vaccine has no significant effect on the PT in patients who are being treated with warfarin. Influenza vaccine can be administered intramuscularly to patients who are receiving anticoagulant therapy without the risk of local bleeding complications.

Precipitation reactions with Newcastle disease virus

Acid precipitated and detergent treated Newcastle disease virus (NDV) antigen was prepared and characterised using the agar gel precipitation (AGP) test. The detergent treated NDV antigen was used to screen antibodies to NDV and the results compared with the conventional haemagglutination inhibition (HI) test titres. AGP test could detect NDV antibodies in serum samples when the corresponding HI titres were 1:8 and above. Detergent treatment of Newcastle disease virus greatly reduced its haemagglutinating ability. Simultaneous detection of antibodies to NDV and infectious bursal disease virus in AGP test was attempted and found successful.

Transcription of a human neurotropic virus promoter in glial cells: effect of YB-1 on expression of the JC virus late gene

We have isolated a partial recombinant cDNA clone from a HeLa expression library which encodes a protein capable of binding to the central region of the human neurotropic JC virus (JCV) enhancer/promoter, termed the B region. Sequence analysis revealed a complete homology of the partial cDNA clone to the N-terminal region, of a previously described DNA-binding protein, termed YB-1. Band shift analyses have indicated that the bacterially produced YB-1 interacts specifically with the double-stranded B oligonucleotide as well as the corresponding single-stranded DNA fragment representing the early promoter sequence. Further analysis indicated that the YB-1 protein binds specifically to the C/T-rich sequence of the B domain, which is located in close proximity to the TATA box within the virus enhancer/promoter. Results from cotransfection experiments demonstrated that the full-length (YB-1) but not the partial cDNA enhances expression of the JCV late (JCVL) promoter in glial cells. Cointroduction into glial cells of a recombinant expressing the YB-1 and JCVL deletion mutants indicated that removal of the C/T-rich sequence of the B domain reduces the level of activation of the virus promoter by YB-1. Further cotransfection experiments revealed that the virus transactivating protein T antigen appears to diminish the ability of YB-1 to activate JCVL gene expression. RNA studies indicated that YB-1 is expressed in several cell types and tissues. Examination of YB-1 RNA from mouse brain at various stages of development revealed high levels of YB-1 RNA at early stages of development and lower levels at all subsequent developmental stages.

Late infantile neuronal ceroid lipofuscinosis: an ultrastructural investigation

Late infantile neuronal lipofuscinosis was confirmed by electron microscopy in this case. At magnifications above 100,000 a particular alternating linear pattern of the curvilinear bodies was found.

Long-term oral anticoagulant therapy: update on indications, therapeutic ranges, and monitoring

Oral anticoagulant therapy is used extensively in the treatment of deep venous thrombosis-pulmonary embolism and prevention of systemic thromboembolism. Adoption of the International Normalized Ratio system for the laboratory monitoring of therapy has solved the problems encountered with the variable sensitivities of the available thromboplastins in North America. Although in recent years the recommended intensity of treatment has been reduced for many indications, bleeding remains the most common side effect of long-term oral anticoagulation therapy. Several drugs interact with warfarin sodium, the most commonly used oral anticoagulant drug, and potentiate its effect, thereby increasing the risk of bleeding. However, awareness of potential drug interactions and careful monitoring to maintain patients within the recommended therapeutic ranges can minimize the risk of bleeding and lead to its safe use in most patients.

Perioperative prophylaxis of venous thromboembolism

Venous thromboembolism is an important cause of morbidity and mortality in hospitalized patients, causing 100,000 to 200,000 deaths per year in the United States. Patients undergoing surgery are at the highest risk of venous thromboembolism. The magnitude of this risk in a patient depends on the surgical procedure performed and the presence of other risk factors that predispose to venous thromboembolism. The clinical diagnosis of both deep vein thrombosis and pulmonary embolism is notoriously inaccurate. Furthermore, two thirds of all fatal pulmonary emboli cause death within 30 minutes of the embolic episode, leaving little time for diagnostic work-up and effective treatment. Prophylactic treatment for prevention of venous thromboembolism is therefore important in these patients, and several effective mechanical and chemical methods for this purpose are available. The pathogenesis of deep vein thrombosis in the surgical patients, the predisposing risk factors, and the available prophylactic modalities are discussed in this article. Recommendations for the use of various approaches in different risk categories are provided.