Rotator cuff muscles lose responsiveness to anabolic steroids after tendon tear and musculotendinous retraction: an experimental study in sheep

Long-standing rotator cuff tendon tearing is associated with retraction, loss of work capacity, irreversible fatty infiltration, and atrophy of the rotator cuff muscles. Although continuous musculotendinous relengthening can experimentally restore muscular architecture, restoration of atrophy and fatty infiltration is hitherto impossible.

Patients with temporomandibular disorders have increased fatigability of the cervical extensor muscles

To determine whether patients with myogenous and mixed temporomandibular disorders (TMD) have greater fatigability of the cervical extensor muscles while performing a neck extensor muscle endurance test (NEMET) when compared with healthy controls.

Multiple small "imaging" branch-duct type intraductal papillary mucinous neoplasms (IPMNs) in familial pancreatic cancer: indicator for concomitant high grade pancreatic intraepithelial neoplasia?

Most screening programs for familial pancreatic cancer are currently based on endoscopic ultrasonography and/or magnetic resonance imaging (MRI). Cystic lesions, especially those suspicious for small intraductal pancreatic mucinous neoplasms (IPMNs) of the branch ducts, can be visualized in up to 40 % of individuals at risk, but their pathological importance in the setting of FPC is yet not well established. Individuals at risk from a prospective screening program for familial pancreatic cancer with small "imaging" IPMNs of the branch-duct type (BD-IPMN) who underwent pancreatic resection were analysed regarding clinico-pathological data and the locations of pancreatic lesions. Five of 125 individuals at risk who underwent screening had multiple small (size 2-10 mm) unicystic lesions and/or multicystic single lesions in the pancreatic body and tail suspicious for BD-IPMNs upon MRI imaging and decided to undergo surgical resection after interdisciplinary counselling, although none fulfilled the consensus criteria for IPMN resection. Histological examination revealed BD-IPMNs with low or moderate dysplasia of the gastric type in combination with multifocal PanIN2 and PanIN3 lesions in 4 individuals. The remaining patient had only tiny ductectasias in the pancreatic tail with multifocal PanIN 2 lesions in the entire gland and one PanIN3 lesion in the pancreatic head. Intriguingly, the location of the most dysplastic histological lesions (PanIN3) did not correspond to the preoperatively detected lesions and were not visible in preoperative imaging. In the setting of FPC, the presence of multiple small "imaging" BD-IPMNs may indicate the presence of high-grade PanIN lesions elsewhere in the pancreas.

Papillary glioneuronal tumor

The descriptive term papillary glioneuronal tumor (PGNT) has been repeatedly applied to a morphologic subset of low-grade mixed glial-neuronal neoplasia of juvenile and young adult patients. We report on a 13-year-old boy with PGNT of the left temporal lobe, who presented with headaches and a single generalized seizure. On magnetic resonance imaging, tumor was seen as a large, moderately enhancing paraventricular mass with cyst-mural nodule configuration and slight midline shift. Perifocal edema was virtually absent. Gross total resection could be performed, followed by an uneventful recovery. Histologically, the tumor exhibited similar, if not identical, features as reported previously. These comprised a patterned biphasic mixture of sheets of synaptophysin-expressing small round cells and pseudorosettes of GFAP-positive rudimentary astrocytes along vascular cores. Focally, the latter imprinted a pseudopapillary aspect on this otherwise solid lesion. Both cellular components expressed non-polysialylated neural cell adhesion molecule (NCAM)-L species, and several overlapping areas of synaptophysin and GFAP immunoreactivity were present. The mean MIB-1 labeling index remained below 1%. Signs of anaplasia, in particular mitotic figures, endothelial proliferation, or necrosis were consistently lacking. We perceive PGNT as a clinically and morphologically well-delineated subgroup of extraventricular neurocytic neoplasia, whose paradigmatic presentation may allow for consideration as an entity.

Basement membrane remodeling in skeletal muscles of patients with limb ischemia involves regulation of matrix metalloproteinases and tissue inhibitor of matrix metalloproteinases

BACKGROUND/AIM: Because the pericapillary basement membrane in skeletal muscles of patients with chronic critical limb ischemia (CLI) is thickened, we determined the expression patterns of genes involved in collagen metabolism, using samples from 9 CLI patients, 4 patients with acute limb ischemia and 4 healthy controls. METHODS: Gene array analysis, quantitative RT-PCR and semiquantitative grading of immunohistochemical reactivity were performed to determine mRNA/cDNA and protein concentrations. RESULTS: In CLI patients compared to controls, cDNA levels of matrix metalloproteinase (MMP)-9 and MMP-19 were higher, collagen type IV chains A1 and A2, tissue inhibitor of matrix metalloproteinase (TIMP)-1 and TIMP-2 were similar and MMP-2 were lower. On the protein level, MMP-2, MMP-9, MMP-19 and TIMP-1 were more abundantly expressed. In skeletal muscles from patients with acute limb ischemia, cDNA and protein levels of MMP-9, MMP-19, collagen type IV chains, TIMP-1 and TIMP-2 were high. MMP-2 was elevated at the protein but decreased on the cDNA level. CONCLUSION: Expression of basement membrane components in skeletal muscles of CLI and acute limb ischemia patients is altered, possibly contributing to the pathogenesis of peripheral arterial disease.

Disorders of paravertebral lumbar muscles: from pathology to cross-sectional imaging

Paravertebral lumbar muscles are important for spine stabilization and mobility. They may be abnormal in several disorders that may be associated with pain or functional impairment. Special attention should be paid to the paravertebral muscles during imaging, so that a possible muscular disease is not overlooked, especially in patients with low back pain. This article reviews such imaging abnormalities.

Upregulation of alpha-skeletal muscle actin and myosin heavy polypeptide gene products in degenerating rotator cuff muscles

Impaired function of shoulder muscles, resulting from rotator cuff tears, is associated with abnormal deposition of fat in muscle tissue, but corresponding cellular and molecular mechanisms, likely reflected by altered gene expression profiles, are largely unknown. Here, an analysis of muscle gene expression was carried out by semiquantitative RT-PCR in total RNA extracts of supraspinatus biopsies collected from 60 patients prior to shoulder surgery. A significant increase of alpha-skeletal muscle actin (p = 0.0115) and of myosin heavy polypeptide 1 (p = 0.0147) gene transcripts was observed in parallel with progressive fat deposition in the muscle, assessed on parasagittal T1-weighted turbo-spin-echo magnetic resonance images according to Goutallier. Upregulation of alpha-skeletal muscle actin and of myosin heavy polypeptide-1 has been reported to be associated with increased muscle tissue metabolism and oxidative stress. The findings of the present study, therefore, challenge the hypothesis that increased fat deposition in rotator cuff muscle after injury reflects muscle degeneration.

MRI detects hemorrhages in the muscles of the back in hypothermia

Morphological findings in death due to hypothermia are variable and predominantly unspecific. Goal of this study was to check the usefulness of post-mortem cross-sectional imaging methods in the diagnosis of externally invisible findings in death due to hypothermia. Three consecutive forensic cases that died due to hypothermia were examined using post-mortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy. MSCT excluded traumatic skeletal and fatty tissue injury. Using MRI, it was possible to detect hemorrhages within the muscles of the back in all three cases, a so far unknown finding in death due to hypothermia. MRI also allowed the detection of hemorrhages in the iliopsoas muscles. Wishnewsky spots remained radiologically undetected using the present examination techniques. In conclusion, hemorrhages of the muscles of the back might serve as a new sign of death due to hypothermia; however, additional studies on their specificity are necessary. Post-mortem MRI is considered as a good diagnosing tool for muscular hemorrhages, with a great potential for examination and documentation.

Papillary fibroelastoma of the heart

BACKGROUND: Fibroelastoma is a rare cardiac tumor that was originally described typically from autopsy findings. Thanks to improved imaging modalities, such tumors are today relatively easy to detect and therefore are actively searched for in patients with unclear embolic events. We present the cases of 2 patients recently treated in our clinic and review the recent literature pertaining to fibroelastomas. METHODS AND RESULTS: An electronic PubMed search revealed 186 cases reported between 1994 and 2003. Ninety-seven percent of the reported fibroelastomas were diagnosed in living patients in their fourth and fifth decades of life. The majority (86%) were symptomatic, with stroke, transient ischemic attack, myocardial infarction, and angina pectoris being the most commonly described. Echocardiography was the typical diagnosis modality. Surgical resection was completed in 95% of the cases. CONCLUSIONS: Although cardiac papillary fibroelastomas are rare and benign tumors, they cannot be considered as harmless endothelial lesions, because related embolic events are frequent and primarily involve adults in their active period of life. Echocardiography must therefore consider fibroelastoma in the differential diagnosis of every unclear systemic embolic event, especially because surgical resection can be considered as curative.

Uncrossed cortico-muscular projections in humans are abundant to facial muscles of the upper and lower face, but may differ between sexes

It is a popular concept in clinical neurology that muscles of the lower face receive predominantly crossed cortico-bulbar motor input, whereas muscles of the upper face receive additional ipsilateral, uncrossed input. To test this notion, we used focal transcranial magnetic brain stimulation to quantify crossed and uncrossed cortico-muscular projections to 6 different facial muscles (right and left Mm. frontalis, nasalis, and orbicularis oris) in 36 healthy right-handed volunteers (15 men, 21 women, mean age 25 years). Uncrossed input was present in 78% to 92% of the 6 examined muscles. The mean uncrossed: crossed response amplitude ratios were 0.74/0.65 in right/left frontalis, 0.73/0.59 in nasalis, and 0.54/0.71 in orbicularis oris; ANOVA p>0.05). Judged by the sizes of motor evoked potentials, the cortical representation of the 3 muscles was similar. The amount of uncrossed projections was different between men and women, since men had stronger left-to-left projections and women stronger right-to-right projections. We conclude that the amount of uncrossed pyramidal projections is not different for muscles of the upper from those of the lower face. The clinical observation that frontal muscles are often spared in central facial palsies must, therefore, be explained differently. Moreover, gender specific lateralization phenomena may not only be present for higher level behavioural functions, but may also affect simple systems on a lower level of motor hierarchy.

Apocrine papillary cystadenoma of a minor salivary gland on the lower lip: case presentation

Cystadenomas are a rare, painless, and slow-growing benign epithelial tumor of the salivary gland. This article describes the case of a papillary cystadenoma in the lower lip of a 46-year-old man. The lesion was removed using a carbon dioxide laser, and there were no signs of recurrence 1 year postoperatively.