Broadband, millimeter-wave antireflection coatings for large-format, cryogenic aluminum oxide optics.

We present two prescriptions for broadband ($ {\sim} 77 - 252\;{\rm GHz} $), millimeter-wave antireflection coatings for cryogenic, sintered polycrystalline aluminum oxide optics: one for large-format (700 mm diameter) planar and plano-convex elements, the other for densely packed arrays of quasi-optical elements-in our case, 5 mm diameter half-spheres (called "lenslets"). The coatings comprise three layers of commercially available, polytetrafluoroethylene-based, dielectric sheet material. The lenslet coating is molded to fit the 150 mm diameter arrays directly, while the large-diameter lenses are coated using a tiled approach. We review the fabrication processes for both prescriptions, then discuss laboratory measurements of their transmittance and reflectance. In addition, we present the inferred refractive indices and loss tangents for the coating materials and the aluminum oxide substrate. We find that at 150 GHz and 300 K the large-format coating sample achieves $ (97 \pm 2)\% $ transmittance, and the lenslet coating sample achieves $ (94 \pm 3)\% $ transmittance.

Hypocalcaemia following total thyroidectomy: early post-operative parathyroid hormone assay as a risk stratification and management tool.

OBJECTIVE: To develop a practical, efficient and predictive algorithm to manage potential or actual post-operative hypocalcaemia after complete thyroidectomy, using a single post-operative parathyroid hormone assay. METHODS: This paper reports a prospective study of 59 patients who underwent total or completion thyroidectomy over a period of 24 months. Parathyroid hormone levels were checked post-operatively on the day of surgery, and all patients were evaluated for hypocalcaemia both clinically and biochemically with serial corrected calcium measurements. RESULTS: No patient with an early post-operative parathyroid hormone level of 23 ng/l or more (i.e. approximately twice the lower limit of the normal range) developed hypocalcaemia. All the patients who initially had post-operative hypocalcaemia but had an early parathyroid hormone level of 8 ng/l or more (i.e. approximately two-thirds of the lower limit of the normal range) had complete resolution of their hypocalcaemia within three months. CONCLUSION: Early post-operative parathyroid hormone measurement can reliably predict patients at risk of post-thyroidectomy hypocalcaemia, and predict those patients expected to recover from temporary hypocalcaemia. A suggested post-operative management algorithm is presented.

Aberrant anatomy of the hypoglossal nerve.

OBJECTIVE: Variant anatomy of the hypoglossal nerve is very rare. We report an unusual intra-operative finding of an aberrant branch of the hypoglossal nerve, encountered during a facial reanimation procedure. CASE REPORT: A 50-year-old man was referred to the head and neck surgery department by the neurosurgeons for hypoglossal-facial nerve anastomosis to treat his facial paralysis, which had occurred following the removal of an intracranial neoplasm. During surgery, we identified an aberrant branch of the hypoglossal nerve, which took a more ventral and superior course in the carotid triangle, prior to entering the base of the tongue. Following further dissection, we found the main trunk of the 'true' hypoglossal nerve. Several interconnecting strands were seen in the proximal aspect of both the aberrant branch and the main trunk of the hypoglossal nerve. These interconnecting fibres appeared to have tethered the main trunk into an abnormal anatomical position. CONCLUSION: As far as we can ascertain, this is the first report of an aberrant branch of the hypoglossal nerve. Although this variant would appear to be extremely rare, surgeons must consider all variations of this nerve during head and neck procedures, in order to minimise iatrogenic complications.

Schizencephaly prevalence, prenatal diagnosis and clues to etiology: a register-based study.

OBJECTIVES: To establish the prevalence and antenatal diagnosis of schizencephaly in the UK. METHODS: Data on schizencephaly were extracted from six regional congenital anomaly registers. RESULTS: Thirty-eight cases of schizencephaly were identified in 2 567 165 livebirths and stillbirths, giving a total prevalence of 1.48/100 000 births (95% CI, 1.01-1.95). Eighteen (47% (95% CI, 31-63%)) of the 38 cases were identified antenatally. No affected fetus had an abnormal karyotype identified. A high proportion of cases of schizencephaly occurred in younger mothers: 63% were aged 24 years or less, significantly higher (P < 0.0001) than the corresponding proportion (26%) of mothers in England and Wales. The majority of cases were not identified until after 22 weeks of pregnancy. Additional anomalies associated with vascular disruption sequences were found in eight cases which had septo-optic dysplasia or absent septum pellucidum, one of which also had gastroschisis. CONCLUSIONS: Schizencephaly occurs more frequently in the fetuses of younger mothers. It is often associated with septo-optic dysplasia, suggesting that the two conditions may share a common origin, arising as a result of destructive processes that cause changes in the brain which only become apparent on ultrasound in the second half of pregnancy.

Superior sagittal sinus thrombosis complicating neck dissection.

OBJECTIVE: To report a superior sagittal sinus thrombosis occurring as a rare complication of neck dissection, and to present a review of published literature. CASE REPORT: A 42-year-old man underwent an elective neck dissection for a tumour stage 2, node stage 2b, tonsillar squamous cell carcinoma, prior to chemoradiotherapy. During surgery, the right internal jugular vein was sacrificed as part of the resection, as tumour was adherent to it. Two weeks after surgery, the patient was readmitted with seizures. Subsequent computed tomography and magnetic resonance venography confirmed a superior sagittal sinus thrombosis. The patient was subsequently anticoagulated and underwent radiotherapy without further complication. A review of pre-operative imaging indicated a dominant internal jugular vein, ligation of which may have been a factor in the subsequent sagittal sinus thrombosis. CONCLUSION: Superior sagittal sinus thrombosis following neck dissection is a rare occurrence, with little reported in the literature. Dominant internal jugular vein anatomy may be evident on pre-operative imaging. An awareness of this complication may be helpful to surgeons contemplating sacrifice of the internal jugular vein.

The hidden mortality of transposition of the great arteries and survival advantage provided by prenatal diagnosis.

OBJECTIVE: To describe the sensitivity of fetal anomaly scanning at detecting transposition of the great arteries (TGA) and to investigate whether prenatal detection improves survival. DESIGN: Retrospective review of survival by comparing those who had an antenatal diagnosis with those who did not. SETTING: Population-based study in Wessex region over 13 years. POPULATION: Babies with isolated TGA and an intact ventricular septum. METHODS: Review of outcomes by comparing those who had an antenatal diagnosis with those who did not. MAIN OUTCOME MEASURES: Mortality rates in each group. RESULTS: TGA occurred more commonly in boys than in girls. Using the existing national screening policy, the antenatal detection rate of TGA was only 6.9% over the study period, improving to 25% in the last 4 years. This contrasts with a 40% detection rate when TGA was associated with a ventricular septal defect (VSD). All the babies who had TGA diagnosed antenatally survived through surgery. Of those who were not diagnosed antenatally, two were stillborn, five died before the diagnosis was made and four died after surgery. Although the difference in survival rates between those who were antenatally diagnosed and those who were not is not statistically significant (chi(2)= 3.9; P = 0.11), some of these deaths could have been prevented if a prenatal diagnosis had been made. CONCLUSIONS: Improved antenatal diagnosis could lead to a significant reduction in the mortality associated with TGA. The current low detection rate of TGA in the UK could be improved by the inclusion of outflow tract views in routine fetal anomaly scans, and we believe that the extra workload is justified.

Comparison of flow cytometric methods for the measurement of ZAP-70 expression in a routine diagnostic laboratory.

Chronic lymphocytic leukaemia (CLL) follows a variable clinical course with patient survival ranging from only a few years despite treatment, to several decades in patients who may never require clinical intervention. Determination of the mutational status of a patient's immunoglobulin heavy chain variable region (Ig V(H)) gene has been used to provide prognostic information, but this assay is not available in most laboratories. The discovery of the expression of the protein tyrosine kinase zeta-associated protein (ZAP)-70 in V(H)-unmutated CLL cases led to its proposal as a surrogate marker for V(H) status. This study investigated the measurement of ZAP-70 expression in CLL using different flow cytometric protocols. Two different antibodies and two different staining methods were compared. The Caltag ZAP-70 antibody and Fix & Perm kit were the easiest to use and were the most sensitive and specific combination, with 91% concordance between ZAP-70 expression and V(H) status. Three patients (9%) were discordant (two V(H) mutated/ZAP-70 positive, and one V(H) unmutated/ZAP-70 negative). No correlation existed between CD38 and either ZAP-70 expression or V(H) status. Measurement of ZAP-70 expression using the Caltag antibody/kit combination provides a standardized flow cytometric method that could be introduced into a routine CLL immunophenotyping panel in a clinical diagnostic laboratory.

The cyclin D1 alternative transcripts [a] and [b] are expressed in normal and malignant lymphocytes and their relative levels are influenced by the polymorphism at codon 241.

BACKGROUND AND OBJECTIVES: The cyclin D1 gene, CCND1, is alternatively spliced to produce transcripts [a] and [b] in a manner apparently modulated by a polymorphism (A/G) at codon 241. Studies have indicated that the polymorphism can affect the prognosis of patients with different types of solid tumors. This study aimed to determine the relative levels of transcripts [a] and [b] in normal and malignant peripheral blood mononuclear cells (PBMNC), and to investigate whether these were influenced by the polymorphism. The impact of the polymorphism on the survival of a group of mantle cell lymphoma (MCL) patients was also to be studied. DESIGN AND METHODS: The polymorphism was genotyped, using restriction fragment length polymorphism analysis, in 74 patients (42 MCL, 19 chronic lymphocytic leukemia, 13 normal controls) and the relative level of transcripts [a] and [b] determined using a competitive reverse transcription polymerase chain reaction method. Kaplan-Meier survival curves and the log-rank test were used to analyze the survival data. RESULTS: Of the cases genotyped, 39 were heterozygous for the polymorphism, 24 homozygous G and 11 homozygous A. Both transcripts [a] and [b] were expressed in normal PBMNC and malignant lymphocytes, with the polymorphism affecting their relative levels. Neither the predominant transcript, nor genotype, significantly influenced survival of the MCL patients studied. INTERPRETATION AND CONCLUSIONS: Contrary to previous reports, patients who were homozygous A at the polymorphism produced more transcript [a] whilst homozygous G patients had more transcript [b]. In the small cohort studied, the polymorphism did not appear to affect the prognosis of the patients with MCL.

Novel baculovirus expression vectors that provide sialylation of recombinant glycoproteins in lepidopteran insect cells.

This report describes novel baculovirus vectors designed to express mammalian beta1,4-galactosyltransferase and alpha2,6-sialyltransferase genes at early times after infection. Sf9 cells infected with these viral vectors, unlike cells infected with a wild-type baculovirus, produced a sialylated viral glycoprotein during the late phase of infection. Thus, the two mammalian glycosyltransferases encoded by these viral vectors are necessary and sufficient for sialylation of a foreign glycoprotein in insect cells under the conditions used in this study. While some of the new baculovirus vectors described in this study produced less, one produced wild-type levels of infectious budded virus progeny.

Characterization of the Oregon isolate of Neospora hughesi from a horse.

Neospora hughesi was isolated in cell cultures inoculated with homogenate of spinal cord from a horse in Oregon. Tachyzoites of this Oregon isolate of N. hughesi were maintained continuously by cell culture passage and tachyzoites were infective to immunosuppressed mice. Gamma interferon gene knockout (KO) mice injected with tachyzoites developed fatal myocarditis and numerous tachyzoites were seen in lesions. Gerbils (Meriones unguiculatus) inoculated with tachyzoites developed antibodies (> or = 1:500) as indicated by the Neospora caninum agglutination test but did not develop clinical signs, and Neospora organisms were not demonstrable in their tissues. Tissue cysts were not found in gerbils, nude mice, KO mice, immunosuppressed outbred Swiss Webster mice, or BALB/c mice injected with the Oregon isolate of N. hughesi. Ultrastructurally, tachyzoites of the Oregon isolate from the myocardium of infected KO mice and from cell culture were similar to N. caninum tachyzoites. Western blot analysis using NcSAG1 and NcSRS2 polyclonal and monoclonal antibodies and characterization of the internal transcribed spacer 1 sequences from the equine isolates and different isolates of N. caninum from dogs and cattle indicated that the Oregon isolate of N. hughesi is distinct from N. caninum isolates from cattle and dogs.

Metastatic disease of the femur. Surgical management.

Treatment of actual or impending pathologic fractures of the femur provides the senior author with some of the most rewarding surgical interventions of his practice. The patients' survival outlook is not changed, but their quality of life is enhanced significantly. Most health care providers usually provide the metastatic cancer patient only temporary symptomatic relief, at best, and often at the expense of continued pain, suffering, or sickness, such as is seen with chemotherapy-associated morbidity. Patients with metastatic bone disease are usually incredibly grateful for the restoration of function and diminution of their pain that results from the proper operation on metastatic bone disease. These patients typically are among the most appreciative patients and often express their gratitude when seen in follow-up in the clinic or office. Despite their metastatic disease state, their usual enthusiasm is uplifting to the surgeon and to the staff. To help a patient be pain-free and functional in the waning days of his or her life affords the patient, the physician, and the physician's staff with an emotionally rewarding experience and one that is well worth the time and effort required to care for these patients. By following the techniques outlined in this article, most patients with metastatic disease of the femur can be appropriately managed with excellent results.

Screening of the entire coding region of p53 in low grade lymphoproliferative disorders.

This report details a rapid method for screening the entire p53 coding region (exons 2-11). This method, based on the non-isotopic RNase cleavage assay, uses novel primer sequences and an adaptation of the MutationScreener method. A mutation in 20% of the sample was easily detectable by this method, whereas mutations below 50% were undetectable using the original method. Alterations to the wild-type p53 mRNA sequence were found in nine of the 130 patients with low grade lymphoproliferative disorders screened, and this was confirmed by DNA sequencing in eight of eight samples. The method is a simple and reliable technique for screening for p53 mutations.