Zinc alpha-2 glycoprotein is implicated in dyslipidaemia in HIV-1-infected patients treated with antiretroviral drugs

OBJECTIVES

Treated HIV-1-infected patients with lipodystrophy often develop insulin resistance and proatherogenic dyslipidaemia. Zinc alpha-2 glycoprotein (ZAG) is a recently characterized adipokine which has been shown to be involved in the development of obesity and metabolic syndrome in uninfected subjects. We assessed the relationship between circulating ZAG levels and metabolic derangements in HIV-1-infected patients receiving antiretroviral drugs.

METHODS

Plasma ZAG levels were assessed in 222 individuals: 166 HIV-1-infected patients treated with antiretroviral drugs (77 with lipodystrophy and 89 without lipodystrophy) and 56 uninfected controls. Plasma ZAG levels were assessed by enzyme-linked immunosorbent assay (ELISA) and were correlated with fat distribution abnormalities and metabolic parameters.

RESULTS

HIV-1-infected patients had lower plasma ZAG levels compared with uninfected controls (P < 0.001). No differences were found in ZAG plasma levels according to the presence of lipodystrophy, components of the metabolic syndrome or type of antiretroviral treatment regimen. Circulating ZAG levels were strongly determined by high-density lipoprotein cholesterol (HDLc) in men (B = 0.644; P < 0.001) and showed a positive correlation with total cholesterol (r = 0.312; P < 0.001) and HDLc (r = 0.216; P = 0.005).

CONCLUSIONS

HIV-1-infected patients have lower plasma ZAG levels than uninfected controls. In infected patients, plasma ZAG levels are in close relationship with total cholesterol and HDLc.

RNA-binding properties and membrane insertion of Melon necrotic spot virus (MNSV) double gene block movement proteins

Advances in structural and biochemical properties of carmovirus movement proteins (MPs) have only been obtained in p7 and p9 from Carnation mottle virus (CarMV). Alignment of carmovirus MPs revealed a low conservation of amino acid identity but interestingly, similarity was elevated in regions associated with the functional secondary structure elements reported for CarMV which were conserved in all studied proteins. Nevertheless, some differential features in relation with CarMV MPs were identified in those from Melon necrotic virus (MNSV) (p7A and p7B). p7A was a soluble non-sequence specific RNA-binding protein, but unlike CarMV p7, its central region alone could not account for the RNA-binding properties of the entire protein. In fact, a 22-amino acid synthetic peptide whose sequence corresponds to this central region rendered an apparent dissociation constant (K(d)) significantly higher than that of the corresponding entire protein (9 mM vs. 0.83-25.7 microM). This p7A-derived peptide could be induced to fold into an alpha-helical structure as demonstrated for other carmovirus p7-like proteins. Additionally, in vitro fractionation of p7B transcription/translation mixtures in the presence of ER-derived microsomal membranes strongly suggested that p7B is an integral membrane protein. Both characteristics of these two small MPs forming the double gene block (DGB) of MNSV are discussed in the context of the intra- and intercellular movement of carmovirus.

Objective patellar instability: MR-based quantitative assessment of potentially associated anatomical features

To evaluate and compare the diagnostic utility of multiple quantitative parameters as measured on knee magnetic resonance (MR) examinations of patients suffering objective patellar instability (OPI). We performed a retrospective evaluation of knee MR examinations in a group of 46 patients (59 knees) with clinically proven OPI, and in a control group of 69 patients (71 knees). Multiple quantitative parameters in both groups were statistically evaluated and compared for their association with OPI. OPI patients tend to present shallower trochlear groove (<5 mm), larger Insall-Salvati index (>1.2), shorter patellar nose (<9 mm), smaller morphology ratio (<1.2), and larger patellar tilt (>11 degrees ) than control patients. The best sensitivities were those of the lateral patellar tilt (92.7%), the trochlear groove depth at the roman arch level (85.7%) and the Insall-Salvati index (78%). The best specificities were those of the morphology ratio (86.9%), the patellar nose (84.5%) and the patellar tendon length (84.5%). Shallow trochlear groove may be confidently identified at the roman arch view in OPI patients. Patella alta may be more reliably detected by the Insall-Salvati index in OPI patients. Patellar nose and morphology ratio are very specific indicators of OPI. A short patellar nose (that is to say, a patellar nose ratio of <0.25) has a high association with OPI. Lateral patellar tilt remains the single feature with the highest sensitivity and specificity for identifying OPI patients.

Surgically repaired massive rotator cuff tears: MRI of tendon integrity, muscle fatty degeneration, and muscle atrophy correlated with intraoperative and clinical findings

OBJECTIVE

Our goal in this study was to evaluate by means of MRI the clinical significance of tendon integrity, muscle fatty degeneration, and muscle atrophy in surgically repaired massive rotator cuff tears and to correlate these and other prognostic factors with intraoperative and clinical findings.

MATERIALS AND METHODS

Twenty-eight surgically proven massive rotator cuff tears were retrospectively included in the study. Twenty-two patients underwent complete repair, and six patients underwent partial repair. Preoperative and postoperative clinical assessment was performed by using the University of California at Los Angeles score. Preoperative and postoperative MRI studies were evaluated for the presence and extent of rotator cuff tear and for the degree of fatty degeneration and atrophy of the rotator cuff muscles.

RESULTS

At a mean 44.4 months' follow-up, 20 patients (71.4%) had a favorable result. A total of 25 patients (89.2%) showed postoperative full-thickness rotator cuff tear, 19 of which were reruptures. A sagittal preoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 100% for predicting a favorable outcome. A coronal postoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 85.7% and a positive predictive value of 92.9% for predicting a favorable outcome. A postoperative fatty degeneration of infraspinatus muscle less than or equal to 2 had a specificity of 87.5% and a positive predictive value of 90.9% for predicting a favorable outcome.

CONCLUSION

Open repair of massive rotator cuff tears may reach a favorable outcome in a significant proportion of patients, despite a high rate of recurrent or residual tears. Oblique coronal sizes of the recurrent or residual tear of less than or equal to 34 mm and postoperative fatty degenerations of infraspinatus muscle of less than or equal to 2 may allow a favorable outcome.

Cementoma of the fibula: imaging findings with histopathologic correlation and review of the literature

Bone tumors containing fibrous tissue and cementum-like spherules are typically found in the maxilla and mandible. However, such lesions are extremely infrequent in the long bones. We report the complete radiologic assessment of a cementoma of the fibula in a 42-year-old man. We also correlate the findings with data provided by histopathologic analysis, and review the English-language literature on tumors of long bones that may contain cementum-like material.

Early intrathoracic migration of Kirschner wires used for percutaneous osteosynthesis of a two-part humeral neck fracture: a case report

We present an unusual case of early migration of three Kirschner wires used for percutaneous osteosynthesis of a two-part humeral neck fracture, causing hemothorax. An 85-year-old woman was admitted to the emergency room after casual accident. She was found to have suffered a two-part fracture of the surgical neck of the right humerus. The humeral fracture was treated by closed reduction and percutaneous osteosynthesis with three threaded Kirschner wires, which were bent subcutaneously. Ten days after the accident the patient presented with dyspnea and laterocervical pain. Plain X-rays and complementary CT demonstrated intrathoracic migration of the three Kirschner wires with hemothorax. Two of the wires were seen under the right clavicle and adjacent to the C7 vertebra. The third wire reached the lateral chest wall. Immediate surgery was performed, with withdrawal of the wires and placement of a drainage tube. The patient had an uneventful recovery after surgery. The humeral fracture resulted in a nonunion, which was well tolerated by the patient and was left untreated. The use of Kirschner wires for osteosynthesis of proximal humeral fractures may cause significant thoracic morbidity, even if various prophylactic measures, including the use of threaded wires, subcutaneous bending, and close radiographic follow-up, are adopted. The use of Kirschner wires should anyway be restricted to carefully selected cases, in order to avoid major complications.

Long-standing Morel-Lavallée lesions of the trochanteric region and proximal thigh: MRI features in five patients

OBJECTIVE

The purpose of this study was to review and describe the MRI features of long-standing Morel-Lavallée lesions of the trochanteric region and proximal thigh in five patients with a history of trauma.

CONCLUSION

Long-standing Morel-Lavallée lesions of the trochanteric region and proximal thigh may present various MRI patterns that reflect their variable composition and stage of development. MRI may prove especially useful for characterizing these lesions when the trauma is remote and progressive growth or pain is present.

Magnetic resonance imaging of anterior cruciate ligament tears: reevaluation of quantitative parameters and imaging findings including a simplified method for measuring the anterior cruciate ligament angle

We evaluated the diagnostic utility of magnetic resonance imaging (MRI) for predicting anterior cruciate ligament (ACL) tears using both quantitative parameters and nonquantitative imaging findings. MRI examinations were retrospectively evaluated in a group of patients with arthroscopically confirmed complete ACL tear and in a control group with arthroscopically confirmed intact ACL. We evaluated multiple MRI features to compare their sensitivity and specificity for detecting ACL tears. Particular emphasis is put on the evaluation of three different quantitative parameters, including a simplified method for measuring the ACL angle. With a threshold value of 45 degrees the ACL angle reached a sensitivity and specificity of 100% for detecting ACL tears. With a threshold value of 0 degrees the Blumensaat angle had a sensitivity of 90% and a specificity of 98%. Finally, a threshold value of 115 degrees gave the posterior cruciate ligament angle a sensitivity of 70% and a specificity of 82%. Discontinuity was found to be the most useful of the ACL abnormalities. Of the secondary findings anterior tibial displacement was the best predictor of ligamentous injury. However, ACL abnormalities and secondary findings, alone or combined, failed to surpass the diagnostic value of the ACL angle for predicting ACL tears. Quantitative parameters are thus good predictors of ACL tears and may increase the overall sensitivity and specificity of MRI. The ACL angle may be confidently measured in a single MRI section and can be considered to be the most reliable quantitative parameter for detecting ACL tears.

MR imaging of spinal infection: atypical features, interpretative pitfalls and potential mimickers

The wide variability of MR features in spinal infection reflects rare distribution of discovertebral involvement, unexpected soft-tissue and bone abnormalities, un-usual complications or uncommon pathogens. In addition, several de-generative and inflammatory entities can clinically and radiologically resemble spinal infection. In this pictorial review, we illustrate the various atypical features that may be found in MR imaging of spinal infection,with emphasis on interpretative pit-falls and common mimickers.

Accessory ossicles and sesamoid bones of the ankle and foot: imaging findings, clinical significance and differential diagnosis

Accessory ossicles and sesamoid bones are frequent findings in routine radiographs of the ankle and foot. They are commonly considered fortuitous and unrelated to the patient's complaint; however, they may eventually cause painful syndromes or degenerative changes in response to overuse and trauma. They may also suffer or simulate fractures. Our aim was to review, illustrate and discuss the imaging findings of some of the more frequent accessory ossicles and sesamoid bones of the ankle and foot region, with particular emphasis on those that may be of clinical significance or simulate fractures.

Clinically significant skeletal variations of the shoulder and the wrist: role of MR imaging

Several skeletal variations of the upper extremity may cause painful conditions or precipitate early degenerative changes, either spontaneously or in response to overuse and trauma. Magnetic resonance imaging has proved particularly useful for accurate interpretation of many of these clinically significant skeletal variations; however, the widespread use of MR imaging may have contributed to over-emphasizing their clinical importance, which is still controversial in many cases. We review, illustrate, and discuss clinically significant skeletal variations of the upper extremity as seen on MR images, particularly those involving the shoulder and the wrist. In the shoulder region, we evaluate variations of acromial and coracoid processes as well as variations and minor dysplastic deformities of the glenoid fossa. We also review different skeletal variations of the carpal region, including ulnar variance, ulnar styloid, lunate morphology, carpal coalition, and carpal accessory ossicles. The role of MR imaging in assessing the clinical importance of such conditions, whether potential, controversial, or well established, is emphasized in this review.

Avulsion fractures and chronic avulsion injuries of the knee: role of MR imaging

Avulsion fractures and chronic avulsion injuries of the knee are common lesions in sports-related trauma, especially among adolescents. Magnetic resonance imaging may prove useful in detecting and characterizing such lesions, and has several advantages with regard to other imaging modalities. We review, illustrate, and discuss the MR imaging features of some of the more frequent avulsion fractures and chronic avulsion injuries of the knee, including avulsion fractures of the cruciate ligaments, avulsion fractures of lateral and medial stabilizers, avulsion fractures and chronic avulsion injuries of the extensor mechanism, and avulsive cortical irregularities of the distal femur. The role of MR imaging in evaluating such lesions is emphasized.

Fluid collections and juxta-articular cystic lesions of the shoulder: spectrum of MRI findings

The MR imaging features of fluid collections and juxta-articular cystic lesions of the shoulder are discussed, with special focus on those related to subacromial impingement and rotator cuff tears. Other more unusual fluid collections and cystic lesions are described, including rice-bodies bursitis, idiopathic synovial osteochondromatosis, dialysis-related amyloid arthropathy, hemophilic arthropathy, infectious conditions, non-infectious inflammatory arthritis, and paralabral cysts.

Dorsal defect on a multi-partite patella: imaging findings

Coincidence of dorsal defect on a multipartite patella constitutes a rare cause of anterior knee pain in the first decades of life. Imaging findings of this uncommon symptomatic skeletal variant are discussed, with emphasis on MR features.

Painful os sustentaculi: imaging findings of another symptomatic skeletal variant

The os sustentaculi is a rare accessory bone of the ankle and foot region. We describe the imaging findings of a symptomatic os sustentaculi in a 49-year-old man. Its clinical significance and associated conditions are also briefly discussed.

Agenesis of the internal carotid artery with a trans-sellar anastomosis: CT and MRI findings in late-onset congenital hypopituitarism

A 29-year-old woman with a history of hypothyroidism since early childhood developed hypopituitarism. CT and MRI revealed anterior pituitary hypoplasia, an ectopic posterior lobe, a Chiari I malformation and agenesis of the right internal carotid artery with a trans-sellar anastomosis. This constellation of findings constitutes a previously unreported association in congenital hypopituitarism of late onset. The usefulness of imaging modalities and the pathogenic implications are also discussed.

Identification of a novel peptide motif that mediates cross-linking of proteins to cell walls

A cDNA clone representing a member of a novel class of cell wall proteins was isolated from tobacco plants. We have designated this protein NtTLRP for tyrosine- and lysine-rich protein. It is structurally related to the previously identified TLRP from tomato plants, sharing a high amino-acid sequence similarity at the C-terminal region. This region contains what appears to be a novel peptide motif which we call CD for cysteine-rich domain, and which is common to several other cell-wall proteins. By using a functional test in transgenic plants, we demonstrate that the presence of the CD domain is per se sufficient to cross-link previously soluble proteins to the cell wall. We present evidence that NtTLRP is cross-linked and specifically localizes to the cell wall of lignified cells. The highly localized deposition of NtTLRP in these cells indicates that this class of cell-wall proteins may have a specialized function in the formation of xylem tissue.

An unusual presentation of secondary pleural hydatidosis

Although pleural involvement is relatively common in cystic hydatid disease, one of the rarest and least known complications is secondary pleural hydatidosis. We report the case of a patient who presented with polycystic secondary pleural hydatidosis 4 yrs after treatment for a pyopneumothorax caused by rupture of a pulmonary cyst near the pleural space. Due to the coexistence of severe chronic obstructive pulmonary disease, surgery was ruled out. The patient was treated with albendazole, with a favourable outcome.

[Esophageal intramural pseudodiverticulosis]

Esophageal intramural pseudodiverticulosis is an uncommon and benign primary disease of the esophagus. Less than 150 cases have been reported. We report a new case diagnosed by endoscopy during the investigation of an upper gastrointestinal bleeding, in a 48-year-old man who was assymptomatic from the esophageal point of view. We discuss the clinical, pathogenic, diagnostic and therapeutic aspects of this disease.