Virtual reality-based orthopedic telerehabilitation

Rehabilitation interventions in remote areas are problematic because of distance and available resources. Orthopedic impairments acquired by individuals in remote areas can then lead to permanent disabilities/loss of function because of lack of appropriate rehabilitation. A system being developed by Rutgers and Stanford Universities provides therapy at the patient's home, with remote monitoring and periodic re-assessment. This telerehabilitation system uses virtual reality and haptic interfaces, and a pair of networked PCs. It is intended for rehabilitation of patients with hand, elbow, knee and ankle impairments. Data from the first patient treated with the telerehabilitation system is encouraging.

Virtual reality-based training for the diagnosis of prostate cancer

Prostate malignancies are the second leading cause of cancer deaths among men. The most common method of detecting this disease is digital rectal examination (DRE). Current DRE training is inadequate, since the number of patients that students can practice on is limited. Furthermore, allied care personnel do not train in screening for prostate cancer. Finally, there is no objective way to follow the improvement in DRE skills for medical personnel. This paper presents a virtual reality-based simulator that addresses the above problems. The prototype consists of a PHANToM haptic interface which provides feedback to the trainee's index finger, a motion restricting board, and an SGI workstation, which renders the patient's anatomy. Four types of prostates were modeled--normal, enlarged with no tumor, incipient malignancy (single tumor), and advanced malignancy (tumor cluster). Human factors studies were conducted on both nonmedical students and urology residents in order to quantify the system usefulness. After only five minutes of training, nonmedical students had a 67% correct diagnosis rate of malignant versus nonmalignant cases. This compared with 56% for urology residents in the same trials. Subjective evaluation by the residents pointed out the need to improve the virtual prostate model realism. A control group formed of urology residents performed the same trials on a modified Merck Procar simulator. The control group scored significantly better (96% correct diagnosis of malignancies). We conclude that the virtual prostate palpation simulator, while promising, needs significant improvement in both model realism and haptic interface hardware.

What drives MRI-measured cortical atrophy in multiple sclerosis?

BACKGROUND

Cortical atrophy, assessed with magnetic resonance imaging (MRI), is an important outcome measure in multiple sclerosis (MS) studies. However, the underlying histopathology of cortical volume measures is unknown.

OBJECTIVE

We investigated the histopathological substrate of MRI-measured cortical volume in MS using combined post-mortem imaging and histopathology.

METHODS

MS brain donors underwent post-mortem whole-brain in-situ MRI imaging. After MRI, tissue blocks were systematically sampled from the superior and inferior frontal gyrus, anterior cingulate gyrus, inferior parietal lobule, and superior temporal gyrus. Histopathological markers included neuronal, axonal, synapse, astrocyte, dendrite, myelin, and oligodendrocyte densities. Matched cortical volumes from the aforementioned anatomical regions were measured on the MRI, and used as outcomes in a nested prediction model.

RESULTS

Forty-five tissue blocks were sampled from 11 MS brain donors. Mean age at death was 68±12 years, post-mortem interval 4±1 hours, and disease duration 35±15 years. MRI-measured regional cortical volumes varied depending on anatomical region. Neuronal density, neuronal size, and axonal density were significant predictors of GM volume.

CONCLUSIONS

In patients with long-standing disease, neuronal and axonal pathology are the predominant pathological substrates of MRI-measured cortical volume in chronic MS.

Oxysterols and cholesterol precursors correlate to magnetic resonance imaging measures of neurodegeneration in multiple sclerosis

BACKGROUND

Cholesterol homeostasis is important for formation and maintenance of myelin and axonal membranes in the central nervous system (CNS). The concentrations of the brain specific cholesterol metabolite 24S-hydroxycholesterol (24OHC) and cholesterol precursors have been shown to be altered in multiple sclerosis (MS). However, how changes in sterol levels relate to the pathological processes in MS is not clear.

METHODS

In this study, we compared serum and cerebrospinal fluid (CSF) sterol levels between 105 MS (51 relapsing-remitting (RR); 39 secondary progressive (SP) and 15 primary progressive (PP)) and 49 control patients. Sterol levels were correlated to magnetic resonance imaging (MRI) markers of disease activity.

RESULTS

We found decreased serum 24OHC and 27-hydroxycholesterol (27OHC) and increased CSF lathosterol in MS patients compared to control patients (p=0.018, p=0.002 and p=0.002, respectively). Subgroup analysis showed that serum 24OHC levels were negatively correlated to normalized brain volume measurements in relapse-onset MS patients (r= -0.326, p=0.004).

CONCLUSIONS

These results confirm that cholesterol homeostasis is disturbed in MS and suggest that changes in cholesterol synthesis are related to neurodegenerative pathological processes as seen on the MRI. The data seem to be in line with the recently reported observation that high dose statins may have a positive effect on clinical disability in secondary progressive MS.

Treatment of temporo-mandibular ankylosis with particular reference to the interposition of full-thickness skin autotransplant

In the treatment of the temporo-mandibular ankylosis, the maintainance of separation between the temporal and mandibular raw surfaces, after osteotomy of the bony fusion, constitutes the key to the prevention of recurrence; the great potential of bone to reform is acknowledged by all those who are experienced in this problem. Analysing 168 temporo-mandibular arthoplasties in which different methods have been used in order to maintain the newly created joint space, the causes of failures have been brought out and the difficulties studied. The conclusion is reached that the best results were obtained by the interposition of autogenous full thickness skin. The surgical technique is briefly presented as well as the records regarding the cases followed-up for a period of 2 to 19 years, illustrating the anatomical and functional conservation of the new joints. The experimental investigations concerning the behaviour and fate of the buried skin autotransplants complete the clinical studies, proving the qualities and the value of full thickness skin as an interposition material in arthroplasties.

Identification of biomarkers for diagnosis and progression of MS by MALDI-TOF mass spectrometry

INTRODUCTION

Body fluid biomarkers for clinical subtyping and monitoring of disease progression are of considerable interest in multiple sclerosis (MS). Proteomics tools are optimal for the unbiased simultaneous detection of large series of peptides and proteins.

OBJECTIVES

To identify novel candidate biomarkers discriminating patients with MS from patients with other neurological diseases (OND), and for subtyping of relapsing-remitting (RR), secondary progressive (SP) and primary progressive (PP) MS patients using a high-throughput MALDI-TOF-based mass spectrometry method.

METHODS

Paired cerebrospinal fluid (CSF) and serum samples of 41 RRMS, 30 SPMS, 13 PPMS patients and 25 patients with OND were analysed.

RESULTS

Out of a total of 100 detected peptides in CSF and 200 peptides in serum, 11 peptides were differentially regulated in serum and two in CSF between patients with MS and the OND control group. Eleven peptides were differentially regulated in both serum and CSF between relapse-onset MS and PPMS patients. Lastly, four peptides were differentially regulated in serum and two in CSF between RRMS and SPMS patients. Specific peaks regulated in MS were tentatively identified as fragments of secretogranin III and complement C3. The peak intensity of the CSF peptide ion with m/z value 8607.7 correlated to atrophy (r = -0.27, p < 0.005), black hole volumes (r = 0.31, p < 0.008) and total lesion load (r = 0.34, p < 0.003). A serum peptide with m/z value of 872.4 elevated in SPMS correlated to Expanded Disability Status Scale (r = 0.341, p < 0.005) and atrophy (r = -0.286, p < 0.028).

CONCLUSIONS

Using high-throughput body fluid profiling by MALDI-TOF mass spectrometry, small proteins and peptides were detected as promising candidate biomarkers for diagnosis and disease progression of MS.

Accurate GM atrophy quantification in MS using lesion-filling with co-registered 2D lesion masks

Background

In multiple sclerosis (MS), brain atrophy quantification is affected by white matter lesions. LEAP and FSL-lesion_filling, replace lesion voxels with white matter intensities; however, they require precise lesion identification on 3DT1-images.

Aim

To determine whether 2DT2 lesion masks co-registered to 3DT1 images, yield grey and white matter volumes comparable to precise lesion masks.

Methods

2DT2 lesion masks were linearly co-registered to 20 3DT1-images of MS patients, with nearest-neighbor (NNI), and tri-linear interpolation. As gold-standard, lesion masks were manually outlined on 3DT1-images. LEAP and FSL-lesion_filling were applied with each lesion mask. Grey (GM) and white matter (WM) volumes were quantified with FSL-FAST, and deep gray matter (DGM) volumes using FSL-FIRST. Volumes were compared between lesion mask types using paired Wilcoxon tests.

Results

Lesion-filling with gold-standard lesion masks compared to native images reduced GM overestimation by 1.93 mL (p < .001) for LEAP, and 1.21 mL (p = .002) for FSL-lesion_filling. Similar effects were achieved with NNI lesion masks from 2DT2. Global WM underestimation was not significantly influenced. GM and WM volumes from NNI, did not differ significantly from gold-standard. GM segmentation differed between lesion masks in the lesion area, and also elsewhere. Using the gold-standard, FSL-FAST quantified as GM on average 0.4% of the lesion area with LEAP and 24.5% with FSL-lesion_filling. Lesion-filling did not influence DGM volumes from FSL-FIRST.

Discussion

These results demonstrate that for global GM volumetry, precise lesion masks on 3DT1 images can be replaced by co-registered 2DT2 lesion masks. This makes lesion-filling a feasible method for GM atrophy measurements in MS.

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In multiple sclerosis brain atrophy measurement is affected by white matter lesions.

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LEAP and FSL-lesion_filling replace lesion voxels with white matter intensities.

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The two lesion-filling methods show differences.

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2D lesion masks can be registered and used for lesion-filling on 3DT1 images.

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This makes lesion-filling a feasible method for atrophy measurements in MS.

Predicting clinical progression in multiple sclerosis after 6 and 12 years

BACKGROUND AND PURPOSE

To predict disability and cognition in multiple sclerosis (MS) after 6 and 12 years, using early clinical and imaging measures.

METHODS

A total of 115 patients with MS were selected and followed up after 2 and 6 years, with 79 patients also being followed up after 12 years. Disability was measured using the Expanded Disability Status Scale (EDSS); cognition was measured only at follow-up using neuropsychological testing. Predictors of interest included EDSS score, baseline brain and lesion volumes and their changes over 2 years, baseline age, clinical phenotype, sex and educational level.

RESULTS

Higher 6-year EDSS score was predicted by early EDSS score and whole-brain volume changes and baseline diagnosis of primary progressive MS (adjusted R²  = 0.56). Predictors for 12-year EDSS score included larger EDSS score changes and higher T1-hypointense lesion volumes (adjusted R²  = 0.38). Year 6 cognition was predicted by primary progressive MS phenotype, lower educational level, male sex and early whole-brain atrophy (adjusted R²  = 0.26); year 12 predictors included male sex, lower educational level and higher baseline T1-hypointense lesion volumes (adjusted R²  = 0.14).

CONCLUSIONS

Patients with early signs of neurodegeneration and a progressive disease onset were more prone to develop both disability progression and cognitive dysfunction. Male sex and lower educational level only affected cognitive dysfunction, which remains difficult to predict and probably needs more advanced imaging measures.

AIDS-associated Kaposi's sarcoma in Romanian children

BACKGROUND

Kaposi's sarcoma (KS) is commonly associated with the acquired immunodeficiency syndrome (AIDS) in adults. Little is known regarding its occurrence in children.

OBJECTIVE

Our purpose was to report the clinical and epidemiologic characteristics of KS in three Romanian children with AIDS and to compare them with previously reported AIDS-associated KS in children.

METHODS

This was a clinicopathologic study and computer-based literature review.

RESULTS

All three Romanian children had skin involvement; two had involvement of lymph nodes and internal organs. All had acquired human immunodeficiency virus (HIV) infection postnatally. Including these children, 33 cases of AIDS-associated KS in children have been reported. Thirteen of 30 evaluable patients had acquired HIV infection postnatally; nine of these children (69%) had cutaneous involvement by KS. A perinatal route of transmission was present in the remaining 17 cases; only two of these children (12%) with KS had cutaneous involvement. No case was noted in which intravenous drug use was the sole parental HIV risk factor.

CONCLUSION

The data support the contention that KS is caused by a second infectious agent prevalent only in certain HIV-infected populations. Children of parents in high-risk groups for KS and children who acquire HIV via contaminated blood or blood products are at highest risk for KS. The route of acquisition of HIV infection may also be associated with different clinical manifestations of KS in children.

Novel insights into the antiproliferative effects and synergism of quercetin and menadione in human leukemia Jurkat T cells

The flavonoid quercetin and menadione (vitamin K3) are known as potent apoptogens in human leukemia Jurkat T cells. We explored some underlying mechanisms and the potential relevance of the combination quercetin-menadione for clinical applications. In acute treatments, quercetin manifested a strong antioxidant character, but induced a transient loss of Δψm, likely mediated by opening of the mitochondrial permeability transition pore. After removal of quercetin, persistent mitochondrial hyperpolarization was generated via stimulation of respiratory Complex I. In contrast, menadione-induced Δψm dissipation was only partially and transiently reversed after menadione removal. Results indicate that Ca(2+) release is a necessary event in quercetin-induced cell death and that the survival response to quercetin is delineated within 1h from exposure. Depending on dose, the two agents exhibited either antagonistic or synergistic effects in reducing clonogenicity of Jurkat cells. 24-h combinatorial regimens at equimolar concentrations of 10-15 μM, which are compatible with a clinically achievable (and safe) scheme, reduced cell viability at efficient rates. Altogether, these findings support the idea that the combination quercetin-menadione could improve the outcome of conventional leukemia therapies, and warrant the utility of additional studies to investigate the therapeutic effects of this combination in different cellular or animal models for leukemia.

Intratumoral ligation in the management of orofacial cavernous haemangiomas

After a short comment on the essential data concerning the pathology, clinical aspects and treatment of orofacial haemangiomas, the author presents his own method of treatment by intratumoral ligation. He describes the technical details by which interception of the blood supply to the haemangioma is achieved and also breakdown of the angiomatous mass into segments by the occlusion of vascular channels, thus completely interrupting the intratumoral blood flow. Obstruction of vascular lumina, endothelial atrophy, blood clot organization in the small diverticula between them and also subsequent fibrous hyperplasia which take the place of the vascular hyperplasia ensue. The method was used in 31 cases of cavernous haemangioma in different sites; the results, with follow-up periods of 1-8 years prove its efficacy.

Bone resection, extra-corporal cryotherapy and immediate re-implantation in the treatment of mandibular tumours

Two aspects have to be considered in the treatment of mandibular tumours: The eradication of the disease, and the maintenance of mandibular continuity to obtain a good functional and aesthetic result. The authors experimented with a cryo-surgical method which consists of mandibular hemiresection, extra corporal immersion of the specimen in liquid nitrogen at - 180 degrees C, followed by re-implantation of the mandibular body in its bed. In this way we achieved the eradication of the tumour and produced an auto-transplant for immediate bone grafting. The clinical and radiological progress of four patients with various mandibular tumours, followed-up for three years, is presented.

Reduced food intake following cerebral intraventricular infusion of glucose in Gallus domesticus

Unanaesthetized hens and cocks were infused into the cerebral lateral ventricle with 0.2 ml of a 6% glucose solution or equal volumes of isotonic saline following a 20-hr total food deprivation period. A more marked suppression of food intake occurred in the next 1-3 hr after glucose rather than after saline. The results provide new evidence that chickens possess central glucoreceptors involved in the regulation of their feeding behavior.

Bioinspired Hydrogel Coating Based on Methacryloyl Gelatin Bioactivates Polypropylene Meshes for Abdominal Wall Repair

Considering the potential of hydrogels to mimic the cellular microenvironment, methacryloyl gelatin (GelMA) and methacryloyl mucin (MuMA) were selected and compared as bioinspired coatings for commercially available polypropylene (PP) meshes for ventral hernia repair. Thin, elastic hydrated hydrogel layers were obtained through network-forming photo-polymerization, after immobilization of derivatives on the surface of the PP fibers. Fourier transform infrared spectroscopy (FTIR) proved the successful coating while the surface morphology and homogeneity were investigated by scanning electron microscopy (SEM) and micro-computed tomography (micro-CT). The stability of the hydrogel layers was evaluated through biodynamic tests performed on the coated meshes for seven days, followed by inspection of surface morphology through SEM and micro-CT. Taking into account that platelet-rich plasma (PRP) may improve healing due to its high concentration of growth factors, this extract was used as pre-treatment for the hydrogel coating to additionally stimulate cell interactions. The performed advanced characterization proved that GelMA and MuMA coatings can modulate fibroblasts response on PP meshes, either as such or supplemented with PRP extract as a blood-derived bioactivator. GelMA supported the best cellular response. These findings may extend the applicative potential of functionalized gelatin opening a new path on the research and engineering of a new generation of bioactive meshes.

On the carbohydrate metabolism of pectoral muscle in the ontogeny of chicken

1. Immediately after hatching, the pectoral muscle has a low glycogen content, and exhibits very low glycogen and high glucose and oxygen consumptions. 2. Drastic metabolic changes occur during the second day and again during the second week of life ("critical periods of the ontogenesis"); the above metabolic pattern is reversed. 3. The insulin sensitivity of the muscle is very low during these critical periods, and high between them. 4. The overall trend of metabolic ontogenesis in the pectoral muscle of the domestic fowl (non-flying bird) seems to have no functional but genetical determination.

Angiomyoma and vascular ectasia of the small bowel as a cause of intestinal bleeding

A case is reported of a 31-year-old woman complaining of recurrent intestinal bleeding caused by an angiomyoma of the wall of the duodenojejunal flexure with diverticular features, accompanied by vascular ectasia of the overlying submucosa.

Effects of cerebral lateral, ventricular infusions of phloridzin on feeding and body weight in Gallus domesticus (L.)

Contrary to earlier findings in rats, cerebral lateral ventricular infusions of 1 X 10(-3) M or 2 X 10(-3) M solutions of phloridzin at a rate of 2.5 micronl/min for 90 min had no significant stimulating effects on food intake and weight gain in hens and cocks. These different responses to intraventricular phloridzin might reflect a difference of sensitivity to the inhibitory action of phloridzin on glucose transport in cerebral cells or certain peculiarities of mechanisms controlling food intake in chickens.

Vertical osteotomy of the ascending rami in mandibular retrognathism

The authors present their experience and conclusions regarding surgical lengthening of the mandible in retrognathism due to bone hypo-development. Thus, in hypotrophies of the ascending ramus, especially in temporo-mandibular ankylosis, they use a longitudinal osteotomy (Popescu 1949); various technical adaptations of this method, in different situations, are described, as well as their association with osteoplasty, utilizing iliac bone grafts or the hypertrophic chin prominence. In retrognathism due to hypo-development of the mandible, when the ascending rami have a good conformation, sagittal osteotomy (Obwegeser 1957, Dal Pont 1961) is preferred.