Calcium pyrophosphate dihydrate deposition disease causing thoracic cord compression: case report

OBJECTIVE AND IMPORTANCE: Calcium pyrophosphate dihydrate (CPPD) deposition disease is being increasingly recognized. Spinal involvement in CPPD deposition disease is rare. When involved, the cervical and lumbar regions are commonly affected. We report a rare case of CPPD deposition disease that caused thoracic cord compression. CLINICAL PRESENTATION: A 45-year-old woman presented with clinical features suggestive of thoracic cord compression. Radiographic findings were consistent with calcification of the ligamenta flava in the lower thoracic levels causing cord compression. Calcification of the ligamentum flavum is commonly attributed to CPPD deposition disease. Evaluation for conditions that might be associated with CPPD deposition disease proved to be negative. INTERVENTION: Laminectomy with removal of the calcified ligamenta flava was performed. Histopathological examination of the excised ligaments revealed evidence of CPPD crystals. Postoperatively, the patient's spasticity decreased and sensations improved, with no significant improvement in motor power. CONCLUSION: Calcification of the ligamenta flava due to CPPD deposition disease is a rare cause of thoracic cord compression. CPPD deposition disease should be entertained in the differential diagnosis of thoracic cord compression.     

Exosomes expressing the self‐antigens myosin and vimentin play an important role in syngeneic cardiac transplant rejection induced by antibodies to cardiac myosin

Long‐term success of heart transplantation is hindered by humoral and cell‐mediated immune responses. We studied preexisting antibodies to cardiac self‐antigens, myosin and vimentin, and exosomes induced by antibodies to self‐antigens in eliciting immune responses to cardiac grafts. After syngeneic heterotopic murine heart transplantation, rabbit anti‐myosin or normal rabbit immunoglobulin was administered at day 0 or 7. Sera were collected after heartbeat cessation, cellular infiltration was analyzed, and exosomes were isolated from sera. Histopathologic examination of the controls' transplanted hearts demonstrated normal architecture, and their sera demonstrated neither antibodies to self‐antigens nor exosomes expressing self‐antigens. Administration of antibodies to cardiac myosin immediately posttransplantation (day 0) but not on day 7 triggered graft failure on day 7, and histopathologic examination revealed marked cellular infiltration with neutrophils and lymphocytes. Histopathologic examination of rejected hearts also demonstrated myocyte damage as sera had increased antibodies to myosin and vimentin and development of exosomes expressing self‐antigens. Administration of exosomes isolated from failed grafts containing self‐antigens induced graft dysfunction; exosomes isolated from stable mice did not induce graft failure. Antibodies to self‐antigens can induce exosomes containing self‐antigens, initiating an immune response and causing graft failure after cardiac transplantation.     

A sensor for needle puncture force measurement during interventional radiological procedures

Computer-based simulation for interventional radiology training has attracted increasing attention in recent years because of its potential to train remotely from patients and to provide objective assessment of proficiency. Yet developing a high fidelity simulator with realistic tactile feedback requires accurate knowledge of forces exerted on medical devices during interventional radiology procedures. This paper presents the development and validation of a force sensor for the measurement of axial forces generated during needle, and combined cannula/trocar, puncture procedures in patients. In order to assess the performance of this sensor, in vitro measurements were obtained using needle penetration of porcine liver, kidney and muscle. The results were compared with forces measured by means of a tensile tester.Calibration results showed that the force sensor has high sensitivity and linearity. Comparison of the force profiles obtained from the sensor and the tensile tester shows that good agreement was achieved in the in vitro studies for all the tissues tested.Preliminary clinical force measurements during arterial puncture and liver biopsy procedures have been performed in patients. An example of force recording for each procedure type is presented.     

Timely triggering of homeostatic mechanisms involved in the regulation of T-cell levels in SIVsm-infected sooty mangabeys

Sooty mangabeys, the natural host of simian immunodeficiency virus (SIVsm), generally avoid progressive depletion of CD4+ T cells and opportunistic infections associated with infection of humans (HIV) and macaques (SIVmac). The means by which the SIVsm-infected mangabeys maintain CD4+ T-cell levels despite high rates of viral replication is unknown. One cytokine that has a key role in the regulation of T-cell levels is interleukin-7 (IL-7). Here, the longitudinal assessment of 6 SIVsm-infected mangabeys identified an early increase in plasma IL-7 levels at weeks 1 to 5 after infection. This IL-7 increase correlated with an early decline in CD4+ T-cell levels (decline of 492-1171 cells/microL) accompanying acute viremia. Elevated IL-7 levels were followed by increased T-cell proliferation (Ki67) and maintenance of lower but stable (more than 500 cells/microL) CD4+ T-cell levels in each mangabey through 37 weeks of infection. These data contrast with our earlier studies in SIVmac-infected macaques, in which the IL-7 increase was delayed until 20 to 40 weeks after infection, just before the onset of simian AIDS. Taken together, these data suggest that timely triggering of IL-7 is important for stabilizing healthy T-cell levels in mangabeys and that timely administration of exogenous IL-7 may show benefit during pathogenic SIVmac and HIV infection.     

Oxidant-free,three-component synthesis of 7-amino-6H-benzo[c]chromen-6-ones under green conditions

An oxidant-free three-component synthesis of biologically significant 7-amino-6H-benzo[c]chromen-6-ones was established involving a Sc(OTf)₃ catalyzed three-component reaction between primary amines, β-ketoesters and 2-hydroxychalcones under green conditions. In this strategy, both the B and C rings of 6H-benzo[c]chromen-6-ones were constructed simultaneously starting from acyclic precursors by generating four new bonds including two C–C, one C–N and one C–O in a single synthetic operation. The mechanism of this sequential cascade process involves the initial formation of a β-enaminone intermediate followed by Michael addition with 2-hydroxychalcone, intramolecular cyclization, dehydration, lactonization and aromatization steps. Unlike the related literature approaches, this reaction delivered the products without the addition of any external oxidants to achieve the key aromatization step.

Three-component synthesis of 7-amino-6H-benzo[c]chromen-6-ones was achieved under oxidant-free green conditions.     

Growing skull fracture: two rare causes

Introduction

Growing skull fractures are rare complications of head injury in young children. Till date, growing skull fractures due to an underlying arrested hydrocephalus or subdural hygroma have not been reported. We are reporting two such rare cases.

Discussion

A 12-year-old male who was a known case of arrested hydrocephalus sustained a mild head injury and was found to have a linear fracture. One month after the initial injury, a soft swelling was noted in the parietal region. Investigations revealed the dilated ventricular system communicating through a growing skull fracture with a subgaleal CSF collection. The patient underwent a ventriculoperitoneal shunt using a high-pressure shunt system. The patient died suddenly 48 h after the surgery. An 8-month-old female child sustained a mild head injury with a linear fracture in the parieto-occipital region. Two months later, the child presented with seizures and a soft, fluctuant swelling in the parieto-occipital region. Imaging revealed a frontoparietal subdural hygroma with mass effect that was communicating through a growing skull fracture with a subgaleal CSF collection. The patient underwent a subduroperitoneal shunt. The shunt tube was removed 3 months later as it protruded through the abdominal wound. Follow-up imaging studies revealed complete resolution of the subdural hygroma with healing of the growing skull fracture.

Conclusions

Growing skull fractures can occur as complications of mild head injury sustained in the setting of either arrested hydrocephalus or subdural hygroma. Hence, close follow-up of patients with skull fracture and arrested hydrocephalus/subdural hygroma is necessary for early diagnosis of growing skull fractures.     

Accelerating bone defects healing in calvarial defect model using 3D cultured bone marrow‐derived mesenchymal stem cells on demineralized bone particle scaffold

Bone defects are usually difficult to be regenerated due to pathological states or the size of the injury. Researchers are focusing on tissue engineering approaches in order to drive the regenerative events, using stem cells to regenerate bone. The purpose of this study is to evaluate the osteogenic differentiation of bone marrow‐derived mesenchymal stem cells (BMSCs) on biologically derived Gallus gallus domesticus‐derived demineralized bone particle (GDD) sponge. The sponges were prepared by freeze‐drying method using 1, 2, and 3 wt% GDD and cross‐linked with glutaraldehyde. The GDD sponge was characterized using scanning electron microscopy, compressive strength, porosity, and Fourier transform infrared. The potential bioactivity of the sponge was evaluated by osteogenic differentiation of BMSCs using 3(4, dimethylthiazol‐2‐yl)‐2, 5‐diphenyltetrazolium bromide assay and quantifying alkaline phosphatase (ALP) activity. in vivo experiments were evaluated through a micro‐computerized tomography (μ ‐CT) and histological assays. The analysis confirmed that an increase in the concentration of the GDD in the sponge leads to a higher bone formation and deposition in rat calvarial defects. Histological assay results were in line with μ ‐CT. The results reported in this study demonstrated the potential application of GDD sponges as osteoinductor in bone tissue engineering in pathological or nonunion bone defects.     

ZEUS (ZIF-based electrochemical ultrasensitive screening) device for isopentane analytics with focus on lung cancer diagnosis

Breath analytics is currently being explored for the development of point-of-care devices in non-invasive disease detection. It is based on the measurement of volatile organic compounds (VOCs) and gases that are produced by the body because of the metabolic pathways. The levels of these metabolites vary due to alteration in the endogenous oxidative stress-related metabolic pathways and can be correlated to understand the underlying disease condition. The levels of exhaled hydrocarbons in human breath can be used to design a rapid, easy to use method for lung cancer detection. This work outlines the development of an electrochemical sensing platform that can be used for the non-invasive diagnosis of lung cancer by monitoring isopentane levels in breath. This electrochemical sensor platform involves the use of [BMIM]BF₄@ZIF-8 for sensing the target analyte. This synthesized nanocomposite offers advantages for gas sensing applications as it possesses unique properties such as an electrochemically active Room Temperature Ionic Liquid (RTIL) and a crosslinking Metal Organic Framework (MOF) that provides increased surface area for gas absorption. This is the first report of a hydrocarbon-based sensor platform developed for lung cancer diagnosis. The developed sensor platform displays sensitivity and specificity for the detection of isopentane up to 600 parts-per-billion. We performed structural and morphological characterization of the synthesized nanocomposite using various analytical techniques such as PXRD, FESEM, FTIR, and DLS. We further analyzed the electrochemical activity of the synthesized nanocomposite using a standard glassy carbon electrode. The application of the nanocomposite for isopentane sensing was done using a commercially available carbon screen printed electrode. The results so obtained helped in strengthening our hypothesis and serve as a proof-of-concept for the development of a breathomics-enabled electrochemical strategy. We illustrated the specificity of the developed nanocomposite by cross-reactivity studies. We envision that the detection platform will allow sensitive and specific sensing of isopentane levels such that it can used for point of care applications in noninvasive and early diagnosis of lung cancer, thereby leading to its early treatment and decrease in mortality rate.

A novel synthesized [BMIM]BF₄@ZIF-8 nanocomposite for electrochemical sensing of isopentane as a biomarker for lung cancer diagnosis.     

Preysyrinx state and shunt dysfunction: an under recognized entity?

Presyrinx state is a relatively recently recognized condition. Prompt identification of this condition and appropriate treatment leads to reversal of the radiological and clinical findings with a good prognosis. Failure to identify this condition in a timely fashion leads to fully established syringomyelia. To date, presyrinx state has not been described as a feature of shunt dysfunction. One such rare case is being reported. A 14-year-old boy who was shunted for postmeningitic hydrocephalus at the age of 2 years and subsequently underwent shunt revision presented for routine follow-up and was found to have shunt dysfunction. CT scan showed panventriculomegaly and MRI studies showed panventriculomegaly with a “presyrinx” state extending from the fourth ventricle up to the thoracic region. Shunt revision led to prompt radiological reversal of the presyrinx state. This case is being reported to highlight the hitherto unreported association of shunt dysfunction and presyrinx state. The literature on presyrinx state is being reviewed with reference to the 20 cases reported earlier.