Metastatic intradural primary spinal osteosarcoma: illustrative case.

BACKGROUND: Osteosarcomas are a common primary bone neoplasm among adolescents but represent 0.2% of all malignancies with an incidence of two to four cases per million persons annually worldwide. Although known to have significant metastatic potential, its rare incidence, treatment resistance, and poor prognosis have rendered it a poorly understood and infrequently documented pathology. OBSERVATIONS: Herein the authors present the first documented case of lumbosacral intradural metastasis of a primary osteosarcoma in a young patient, possibly via intradural dissemination following pinhole durotomy in a prior thoracic surgery. LESSONS: Osteosarcomas remain a difficult pathology to treat, particularly upon metastatic dissemination. The utility of adjuvant radiotherapy after resection of an osteosarcoma is increasingly evident in the reduction of local recurrence. In the context of intraoperative pinhole durotomies in resections of high-grade lesions, due consideration should be given to whole-spine radiation, although this remains an evidence-free zone.

Prone thoracic endovascular aortic repair via the popliteal artery for inadvertent vascular injury during spondylectomy: a case report.

Background: Vascular injury during spinal surgery is a dreaded complication associated with high morbidity and mortality. Repositioning the patient following such an injury could result in significant time delays and haemorrhage. Endovascular repair via popliteal access has never previously been described in the literature. A novel prone thoracic endovascular aortic repair (TEVAR) technique is described here as a safe alternative to manage vascular injury during posterior spinal surgery. Case Description: Here we describe a 63-year-old male where endovascular repair of vascular injury to the aorta by intercostal artery avulsion was performed via popliteal artery access in the prone position during T11 en bloc spondylectomy and posterior fusion. The patient remained haemodynamically unstable following the vascular injury precluding immediate transfer to the angiography suite. Identification of vascular injury to deployment of TEVAR graft was 90 minutes. The spondylectomy was able to be completed without repositioning the patient. Radiological and clinical follow-up revealed no complications at 1 and 2 months respectively following surgery. Conclusions: TEVAR placement via this novel popliteal access route was able to halt the haemorrhage allowing stabilisation of the patient and completion of the spinal procedure. Clinical teams should be made aware this is a viable technique to address vascular injuries during spinal surgery.

Telecom-wavelength spectra of a Rydberg state in a hot vapor.

We study telecom-wavelength spectra of a Rydberg state in an atomic vapor with a three-photon excitation scheme. Two lasers of 780 nm and 776 nm are used to pump rubidium-85 atoms in a vapor cell to the 5D5/2 state, from which a probe beam of 1292 nm in the O-band telecommunication wavelength drives a transition to the 21F7/2 Rydberg state. We investigate the probe spectra over the power of pump lasers. The simulation based on a 4-level theoretical model captures the main features of the experimental results. This spectroscopic study paves the way for future experiments of making a direct link between fiber optics and radio transmission via Rydberg atoms.

Empirical LiK excited state potentials: connecting short range and near dissociation expansions.

We report on a high-resolution spectroscopic survey of 6Li40K molecules near the 2S + 4P dissociation threshold and produce a fully empirical representation for the B1Π potential by connecting available short- and long-range data. The purpose is to identify a suitable intermediate state for a coherent Raman transfer to the absolute ground state, and the creation of a molecular gas with dipolar interactions. Starting from weakly bound ultracold Feshbach molecules, the transition frequencies to twenty-six vibrational states are determined. Our data are combined with long-range measurements [Ridinger et al., EPL, 2011, 96, 33001], and near-dissociation expansions for the spin-orbit coupled potentials are fitted to extract the van der Waals C6 dispersion coefficients. A suitable vibrational level is identified by resolving its Zeeman structure and by comparing the experimentally attained g-factor to our theoretical prediction. Using mass-scaling of the short-range data for the B1Π [Pashov et al., Chem. Phys. Lett., 1998, 292, 615620] and an updated value for its depth, we model the short- and the long-range data simultaneously and produce a Rydberg-Klein-Rees curve covering the entire range.

Directional THz generation in hot Rb vapor excited to a Rydberg state.

We optically excite 85Rb atoms in a heated vapor cell to a low-lying Rydberg state 10D5/2 and observe directional terahertz (THz) beams at 3.3 THz and 7.8 THz. These THz fields are generated by amplified spontaneous emission from the 10D5/2 state to the 11P3/2 and 8F7/2 states, respectively. In addition, we observe ultraviolet (UV) light produced by four-wave mixing of optical pump lasers and the 3.3 THz field. We characterize the generated THz power over the detuning and power of pump lasers, and identify experimental conditions favoring THz and UV generation, respectively. Our scheme paves a new pathway towards generating high-power narrowband THz radiation.

Traumatic cerebrospinal fluid oculorrhea managed with an external ventricular drain.

Cerebrospinal fluid (CSF) leaks following head injuries are rare complications with significant morbidity and mortality if left untreated. CSF oculorrhea secondary to a cranio-orbital fistula is a rare presentation of this complication. Standard treatment for a CSF leak involves management of intracranial pressure, CSF diversion and surgical repair of any dural defect. Lumbar drains have commonly been inserted to aid in diverting CSF. We describe a case of a 16-year-old male who presented with an open comminuted depressed skull fracture and CSF oculorrhea. Following a bifrontal decompressive craniectomy, he was successfully treated with CSF diversion following a conservative trial using an external ventricular drain. The use of an external ventricular drain for this purpose has not been described in the literature to date. We report this case as a method of demonstrating the use of an external ventricular drain to adequately divert CSF.

Stability of a frequency-comb-based transfer-lock using a passive Fabry-Perot resonator.

We report on a transfer-lock laser frequency stabilization that utilizes a frequency comb (FC) and a radio frequency counter referenced to a GPS frequency standard to compensate for the frequency drifts of two lasers, which are locked to a single passive Fabry-Perot resonator (FPR). The method requires only one optical phase lock with the FC and allows transfer locking of lasers at wavelengths beyond the usable range of the FC. To attain a large frequency tuning range for the lasers, we implement optical serrodyning. We further demonstrate an efficient scheme to suppress residual amplitude modulation, thereby improving the stability of the Pound-Drever-Hall lock used in this case. The absolute frequency stability was found to be better than 2×10-13 on timescales up to 300 s. Hence, together with the frequency stability on short timescales provided by the FPR, this scheme facilitates coherent Raman spectroscopy as needed for an example for the production of ultracold dipolar heteronuclear molecules.

Spouse depression and disease course among persons with rheumatoid arthritis.

OBJECTIVE: To examine the role of spouse mood in the disability and disease course of persons with rheumatoid arthritis (PWRA). METHODS: A total of 133 married PWRA completed questionnaires, including the Rheumatoid Arthritis Disease Activity Index and the Disabilities of the Arm, Shoulder, and Hand, assessing PWRA arthritis disease activity and disability, respectively, at 2 time points 1 year apart. In addition, both PWRA and their spouses completed the Center for Epidemiologic Studies Depression Scale, a standardized community measure of depression at both time points. RESULTS: Multiple regression analysis revealed spouse depressive symptoms at initial assessment to be predictive of followup PWRA disability and disease activity, even after controlling for initial levels of PWRA depression, disability, disease activity, age, number of years married, education, disease duration, and employment. Specifically, higher levels of spouse depression predicted worse disease course over a 1-year period for PWRA, as indicated by higher reports of subsequent PWRA disability and disease activity. CONCLUSION: Our findings highlight the key role played by the spouse in PWRA disease course, and point to the importance of including the spouse in clinical interventions. Implications for theory, research, and treatment are discussed with a focus on examining pathways through which spouse depressive symptoms may affect PWRA disease course and disability.

Statins may not protect against vasospasm in subarachnoid haemorrhage.

Statins have been shown in two recent small phase I/II trials to be associated with a marked reduction in clinical and transcranial Doppler (TCD) evidence of vasospasm after aneurysmal subarachnoid haemorrhage (SAH). The purpose of this study was to assess the clinical impact of this treatment in a larger number of patients. Fifty-eight individuals were treated in the year before, and 72 patients treated in the year after, the introduction of a 2week course of 40mg/day pravastatin therapy for SAH. Statins did not result in reduced TCD velocities, clinical or angiographic vasospasm, or improvements in global outcome at the time of hospital discharge. A measurable reduction in the rates of vasospasm was expected, based on the size of the effect of statin therapy in the previous small studies. There remains significant uncertainty as to the role of statins in preventing vasospasm after SAH.

The T-cell protein tyrosine phosphatase is phosphorylated on Ser-304 by cyclin-dependent protein kinases in mitosis.

Two alternatively spliced forms of the human protein tyrosine phosphatase TCPTP (T-cell protein tyrosine phosphatase) exist: a 48 kDa form that is targeted to the endoplasmic reticulum (TC48) and a shorter 45 kDa form that is targeted to the nucleus (TC45). In this study we have identified Ser-304 (Phe301-Asp-His-Ser304-Pro-Asn-Lys307) as a major TCPTP phosphory-lation site and demonstrate that TC45, but not TC48, is phosphorylated on this site in vivo. Phosphorylation of TC45 on Ser-304 was cell cycle-dependent, and increased as cells progressed from G2 into mitosis, but subsided upon mitotic exit. Ser-304 phosphorylation was increased when cells were arrested in mitosis by microtubule poisons such as nocodazole, but remained unaltered when cells were arrested at the G2/M checkpoint by adriamycin. Phosphorylation of Ser-304 did not alter significantly the phosphatase activity or the protein stability of TC45, and had no apparent effect on TC45 localization. Ser-304 phosphorylation was ablated when cells were treated with the CDK (cyclin-dependent protein kinase) inhibitors roscovitine or SU9516, but remained unaltered when ERK1/2 activation was inhibited with the MEK (mitogen-activated protein kinase/extracellular-signal-regulated kinase kinase) inhibitor PD98059. In addition, recombinant CDKs, but not the Polo-like kinase Plk1, phosphorylated Ser-304 in vitro. Our studies identify Ser-304 as a major phosphorylation site in human TCPTP, and the TC45 variant as a novel mitotic CDK substrate.

Nuclear transport of parathyroid hormone (PTH)-related protein is dependent on microtubules.

PTH-related protein (PTHrP) was first discovered as a circulating factor secreted by certain cancers and is responsible for the syndrome of humoral hypercalcemia of malignancy induced by various tumors. The similarity of its N terminus to that of PTH enables PTHrP to share the signaling properties of PTH, but the rest of the molecule possesses distinct functions, including a role in the nucleus/nucleolus in reducing apoptosis and enhancing cell proliferation. PTHrP nuclear import is mediated by importin beta1. In this study we use the technique of fluorescence recovery after photobleaching to demonstrate the ability of PTHrP to shuttle between cytoplasm and nucleus and to visualize directly the transport of PTHrP into the nucleus in living cells. Endogenous and transfected PTHrP was demonstrated to colocalize with microtubule structures in situ using various high-resolution microscopic approaches, as well as in in vitro binding studies, where importin beta1, but not importin alpha, enhanced the microtubular association of PTHrP with microtubules. Significantly, the dependence of PTHrP nuclear import on microtubules was shown by the inhibitory effect of pretreatment with the microtubule-disrupting agent nocodazole on nuclear-cytoplasmic flux. These results indicate that PTHrP nuclear/nucleolar import is dependent on microtubule integrity and are consistent with a direct role for the cytoskeleton in protein transport to the nucleus.