Imaging of compressive vertebral haemangiomas

Compressive vertebral haemangiomas (VHs) are rare. Correct preoperative diagnosis is useful both for operative planning (since compressive VHs are extremely vascular lesions) and to allow preoperative embolisation. Numerous radiological signs for VHs have been described, but compressive VHs frequently have atypical features. In particular, magnetic resonance features are not well established. We present imaging features in three cases of compressive VH and review the imaging findings in an additional 106 previously published cases. Findings were typical in 52 of 80 plain film (65 %), 33 of 41 computed tomography (80 %) and 13 of 25 magnetic resonance examinations (52 %). The prevalence of previously described imaging features is reported. Awareness of the range of magnetic resonance features is important since this is frequently the initial investigation in patients presenting with symptoms of neural compression. Since computed tomography is typical in 80 % of cases, this is a useful confirmatory test if magnetic resonance features are suspicious but not diagnostic of compressive VH. Received: 6 August 1999; Revised: 4 November 1999; Accepted: 4 November 1999     

Topical methyl nicotinate-induced skin vasodilation in diabetic neuropathy

OBJECTIVE: To evaluate the vasodilation induced by topical application of methyl nicotinate (MN) and to compare it with the vasodilatory response to acetylcholine (ACh) and sodium nitroprusside (SNP) in healthy subjects and diabetic neuropathic patients. RESEARCH DESIGN AND METHODS: Ten diabetic patients with peripheral neuropathy (DN) and 10 age- and sex-matched healthy control subjects (C) were enrolled. The vasodilatory response to topical application of 1% MN and a placebo emulsion at the forearm and dorsum of the foot skin at 5, 15, 30, 60 and 120 min was measured using Laser Doppler Perfusion Imaging. The vasodilatory response to iontophoresis of 1% ACh and 1% SNP solutions was also evaluated. RESULTS: The maximal vasodilatory response to ACh, SNP and MN was similar at the forearm and foot level in the diabetic patients. In the control group, the responses to MN, ACh and SNP were similar on the forearm but in the foot, the MN vasodilatory response was higher when compared to the ACh and SNP responses. MN-related vasodilation was present 5 min after the application, reached its peak at 15-30 min and declined to pre-application levels 120 min afterward. CONCLUSIONS: Topical application of MN at the forearm and foot levels of diabetic neuropathic patients results in skin vasodilation that is comparable to the maximal vasodilation that can be induced by iontophoresis of ACh or SNP and lasts for less than 2 h. Further studies will be required to explore the potential of MN to increase blood flow and to prevent diabetic foot problems in clinical practice.     

Attitudes towards domestic violence in Lebanon: a qualitative study of primary care practitioners

Background

Domestic violence (DV) is highly prevalent in the developing and developed world. Healthcare systems internationally are still not adequately addressing the needs of patients experiencing violence.

Aim

To explore physicians’ attitudes about responding to DV, their perception of the physician’s role, and the factors that influence their response.

Design and setting

Qualitative study using individual interviews among primary care practitioners working in Lebanon.

Method

Primary care clinicians practising for >5 years and with >100 patient consultations a week were interviewed. Physicians were asked about their practice when encountering women disclosing abuse, their opinion about the engagement of the health services with DV, their potential role, and the anticipated reaction of patients and society to this extended role.

Results

Physicians felt that they were well positioned to play a pivotal role in addressing DV; yet they had concerns related to personal safety, worry about losing patients, and opposing the norms of a largely conservative society. Several physicians justified DV or blamed the survivor rather than the perpetrator for triggering the violent behaviour. Moreover, religion was perceived as sanctioning DV.

Conclusion

Perceived cultural norms and religious beliefs seem to be major barriers to physicians responding to DV in Lebanon, and possibly in the Arab world more generally. Financial concerns also need to be addressed to encourage physicians to address DV.     

Do Hv1 proton channels regulate the ionic and redox homeostasis of phagosomes?

Recent work on animal models has revealed the important role played by the voltage-gated proton channel Hv1 during bacterial killing by innate immune cells. Studies from mice lacking Hv1 channels showed that Hv1 proton channels are required for high-level production of reactive oxygen species (ROS) by the NADPH oxidase of phagocytes (NOX2) in two ways. First, Hv1 channels maintain a physiological membrane potential during the respiratory burst of neutrophils by providing a compensating charge for the electrons transferred by NOX2 from NADPH to superoxide. Second, Hv1 channels maintain a physiological cytosolic pH by extruding the acid generated by the NOX2-dependent consumption of NADPH. The two mechanisms directly sustain the activity of the NOX2 enzyme and indirectly sustain other neutrophil functions by enhancing the driving force for the entry of calcium into cells, thereby boosting cellular calcium signals. The increased depolarization of Hv1-deficient neutrophils aborted calcium responses to chemoattractants and revealed adhesion and migration defects that were associated with an impaired depolymerization of the cortical actin cytoskeleton. Current research aims to transpose these findings to phagosomes, the phagocytic vacuoles where bacterial killing takes place. However, the mechanisms that control the phagosomal pH appear to vary greatly between phagocytes: phagosomes rapidly acidify in macrophages but remain neutral for several minutes in neutrophils following ingestion of solid particles, whereas in dendritic cells phagosomes alkalinize, a mechanism thought to promote antigen cross-presentation. In this review, we discuss how the knowledge gained on the role of Hv1 channels at the plasma membrane of neutrophils can be used to study the regulation of the phagosomal pH, ROS, membrane potential, and calcium fluxes in different phagocytic cells.     

Cheesy material on macroscopic on-site evaluation after endoscopic ultrasound-guided fine-needle biopsy: Don't miss the tuberculosis

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is an excellent investigation to diagnose pancreatic lesions and has shown high accuracy for its use in pathologic diagnosis. Recently, macroscopic on-site evaluation (MOSE) performed by an endoscopist was introduced as an alternative to rapid on-site cytologic evaluation to increase the diagnostic yield of EUS-FNB. The MOSE of the biopsy can estimate the adequacy of the sample directly by the macroscopic evaluation of the core tissue obtained from EUS-FNB. Isolated pancreatic tuberculosis is extremely rare and difficult to diagnose because of its non-specific signs and symptoms. Therefore, this challenging diagnosis is based on endoscopy, imaging, and the bacteriological and histological examination of tissue biopsies. This uncommon presentation of tuberculosis can be revealed as pancreatic mass mimicking cancer. EUS-FNB can be very useful in providing a valuable histopathological diagnosis. A calcified lesion with a cheesy core in MOSE must be suggestive of tuberculosis, leading to the request of the GeneXpert, which can detect Mycobacterium tuberculosis deoxyribonucleic acid and resistance to rifampicin. A decent diagnostic strategy is crucial to prevent unnecessary surgical resection and to supply conservative management with antitubercular therapy.     

Differentiation in B-precursor acute lymphoblastic leukemia cell populations with CD34-positive subpopulations.

B-precursor acute lymphoblastic leukemia bone marrow specimens that contained subpopulations of cells with immunophenotypes corresponding to early (CD34) and late (CD20) and (CD22) stages of normal B-cell differentiation were studied. Subpopulations of cells were isolated according to immunophenotype and then analyzed by both a clonogenic assay and molecular genetic methods. Clonal equivalence of the early and late immunophenotypic subpopulations was confirmed for each case by the demonstration of identical lg gene rearrangements. The in vitro colony-forming assay consistently showed a growth advantage for the CD34+ subpopulations over the CD34- subpopulations. CD34 mRNA was detected readily in these isolated precursor cells. When two specimens in which virtually all of the leukemia cells were CD34+ and CD34+CD20+ and CD34+CD22+ subpopulations were also present the CD34 mRNA was limited to the cells without the late-stage differentiation antigens on their surface. Furthermore, the c-myb mRNA was found only in the subpopulations that also contained CD34 mRNA. Our results show that a limited program of differentiation reminiscent of normal B-cell development may be present in this leukemia.