Intracranial transthecal subarachnoid fat emboli and subarachnoid haemorrhage arising from a sacral fracture and dural tear

We present the case of a 28-year-old man with an unusual aetiology of lipid-dense material in the subarachnoid space. CT of the head at presentation was normal. MRI of the spine revealed a defect in the dura at L5/S1, with avulsed left L5 and S1 nerve roots. Haematoma and marrow fat were observed in close relation to the dural tear adjacent to the sacral fracture. Head CT and MRI subsequently demonstrated new lipid-dense material and haemorrhage in the subarachnoid space after sacral instrumentation, presumably owing to transthecal displacement of fatty marrow.The presence of fat droplets within the subarachnoid space is an unusual finding and is most commonly the sequelae of a ruptured dermoid. We present a unique case with CT and MRI that demonstrates the development of subarachnoid fat emboli and subarachnoid haemorrhage secondary to pelvic trauma. A sacral fracture with an adjacent dural tear and nerve root avulsion is the putative source of the subarachnoid fat and blood.     

A Prospective Study on the Association Between Lower Urinary Tract Symptoms (LUTS) and Erectile Dysfunction: Results from a Large Study in Elderly Chinese in Southern China

IntroductionAlthough many cross-sectional studies have been conducted on the association between lower urinary tract symptoms (LUTS) and erectile dysfucntion (ED), no studies were prospective in Asia.AimThe relationship between LUTS and ED is examined using a prospective cohort of 2000 Chinese men.MethodsBaseline and 4-year data from a large prospective cohort study of 2000 Chinese elderly men were analyzed. A total of 1,736 subjects were included in the current analysis after excluding those with history of bladder or prostate cancer, or urological surgery, and those who used alpha blockers or anti-androgen.Main Outcome MeasuresLUTS were measured at baseline by the International Prostatic Symptom Score and ED was measured using one question on impotence at the end of 4 years.ResultsA dose–response relationship was observed for the relationship between baseline severity of LUTS and severity of ED at follow-up with those who had more severe LUTS at baseline with an increased odds of having more severe ED (odd ratio [OR] = 1.86, confidence interval [CI]: 1.16–2.97 for mild LUTS at baseline; OR = 2.95, CI: 1.81–4.81 for moderate LUTS at baseline; and OR = 3.82, CI: 2.00–7.27 for severe LUTS at baseline). Other baseline factors that were statistically significantly associated with ED included body mass index (OR = 1.13, CI: 1.01–1.26), hypertension (OR = 1.30, CI: 1.02–1.65) and diabetes (OR = 1.44, CI: 1.07–1.93).ConclusionThe presence of LUTS is associated with ED with more severe LUTS being associated with higher degree of ED in men. Wong SY, Leung JC, and Woo J. A prospective study on the association between lower urinary tract symptoms (LUTS) and erectile dysfunction: Results from a large study in elderly chinese in southern China. J Sex Med 2009;6:2024–2031.     

Change in cross‐sectional area of esophageal muscle does not correlate with the outcome of achalasia after pneumatic balloon dilatation

Background and Aim: Patients with achalasia have a thicker muscularis propria compared to normal patients. Because pneumatic balloon dilatation (PD) is an effective treatment for achalasia, the changes in the esophageal muscles after PD may predict treatment outcomes, if muscular change is of primary importance. In the present study, we aimed to observe the changes in esophageal muscle thickness following PD and assessed whether symptom relapse can be predicted on the basis of the esophageal muscle cross‐sectional area (CSA), as measured by high‐frequency intraluminal ultrasound (HFIUS). Methods: Fifteen patients treated by PD were studied and followed up for a median of 3.6 years. An HFIUS was done before PD and 6 months after PD. The esophageal muscle CSA measured at the lower esophageal sphincter (LES), and 3 and 6 cm above the LES, was used to see whether any association was present between symptom recurrence and the esophageal muscle CSA. Results: A single PD resulted in a 2‐year remission rate of 66%. A significance variance in change (?65%–248%) was noticed in the muscle CSA after PD. The predilation muscle CSA, post‐dilation muscle CSA, and change in the muscle CSA after PD was not associated with symptom recurrence. Conclusion: Our findings suggest that measuring the muscle CSA does not help to predict treatment outcome. Muscular changes in achalasia might be just reactive changes.     

PEST family phosphatases in immunity, autoimmunity, and autoinflammatory disorders

Summary:  The proline-, glutamic acid-, serine- and threonine-rich (PEST) family of protein tyrosine phosphatases (PTPs) includes proline-enriched phosphatase (PEP)/lymphoid tyrosine phosphatase (LYP), PTP-PEST, and PTP-hematopoietic stem cell fraction (HSCF). PEP/LYP is a potent inhibitor of T-cell activation, principally by suppressing the activity of Src family protein tyrosine kinases (PTKs). This function seems to be dependent, at least in part, on the ability of PEP to bind C-terminal Src kinase (Csk), a PTK also involved in inactivating Src kinases. Interestingly, a polymorphism of LYP in humans (R620W) is a significant risk factor for autoimmune diseases including type 1 diabetes, rheumatoid arthritis, and lupus. The R620W mutation may be a 'gain-of-function' mutation. In non-hematopoietic cells, PTP-PEST is a critical regulator of adhesion and migration. This effect correlates with the aptitude of PTP-PEST to dephosphorylate cytoskeletal proteins such as Cas, focal adhesion associated-kinase (FAK), Pyk2, and PSTPIP. While not established, a similar function may also exist in immune cells. Additionally, overexpression studies provided an indication that PTP-PEST may be a negative regulator of lymphocyte activation. Interestingly, mutations in a PTP-PEST- and PTP-HSCF-interacting protein, PSTPIP1, were identified in humans with pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome and familial recurrent arthritis, two autoinflammatory diseases. These mutations abrogate the ability of PSTPIP1 to bind PTP-PEST and PTP-HSCF, suggesting that these two PTPs may be negative regulators of inflammation.     

Tat Peptide Is Capable of Importing Large Nanoparticles Across Nuclear Membrane in Digitonin Permeabilized Cells

Understanding the capabilities and limitations of nuclear import is crucial to efficient delivery of macromolecules and nanoparticles for diagnosis and targeted therapy of diseases. Here we report the Tat peptide-mediated import of different cargos into cell nucleus, including dye-labeled streptavidin protein, 43 and 90 nm fluorescent beads, as well as ~20 nm quantum dots for kinetic measurements. Our results revealed significant differences between Tat- and NLS-mediated nuclear import: unlike delivery with the NLS, Tat peptide-based delivery is not inhibited by WGA blockage nor does it require ATP. Surprisingly, Tat peptide was able to import 90 nm beads into the nuclei of digitonin-permeabilized cells, suggesting that its interaction with the nuclear envelope follows a mechanism different from that of NLS. The import kinetics was quantified using Tat peptide-conjugated QDs, yielding a kinetic constant of 0.0085 s⁻¹. Taken together, our results suggest that, compared with NLS, Tat peptide-mediated nuclear import is faster, follows a different pathway, and is capable of importing large nanoparticles. These results have significant implications for the development of new approaches for delivery of cargo into the nuclei of living cells.     

Percutaneous sacroplasty with the use of C-arm flat-panel detector CT: technical feasibility and clinical outcome

Purpose  

Sacroplasty for sacral insufficiency fractures (SIFs) has been performed mostly under computed tomography (CT) or fluoroscopy guidance. The purposes of this study are to describe technical tips and clinical outcomes of sacroplasty under C-arm flat panel detector CT (C-arm CT) guidance, and to compare the cement distributions shown on C-arm CT with those on multi-detector CT (MDCT).     

Bilateral hyperexcitability of thalamic VPL neurons following unilateral spinal injury in rats

In the present study, we have examined whether spinal hemisection injury induces changes in the electrophysiological properties of thalamic ventral posteriorlateral (VPL) neurons in rats. Male Sprague–Dawley rats were subjected to unilateral spinal cord injury by transverse hemisection at the T13 spinal segment. Four weeks after the T13 spinal hemisection, the injured rats displayed robust allodynic behaviors on both sides of hindpaws compared to sham controls (P < 0.05). Extracellular recordings taken 4 weeks after the hemisection revealed that wide dynamic range (WDR) neurons had significantly increased spontaneous and brush-, pressure-, and pinch-evoked activities, respectively, on both sides of the thalamic VPL regions (P < 0.05). In contrast, low threshold (LT) neurons showed only an increase in the brush-evoked activity compared to sham controls (P < 0.05). However, afterdischarge activity in both types of neurons showed no changes. In addition, both sides of the thalamic VPL regions showed higher incidences of WDR neurons. In conclusion, our data demonstrate that spinal unilateral injury induces bilaterally increased evoked activity in thalamic VPL neurons.