Artificial exosomes for translational nanomedicine.

Exosomes are lipid bilayer membrane vesicles and are emerging as competent nanocarriers for drug delivery. The clinical translation of exosomes faces many challenges such as massive production, standard isolation, drug loading, stability and quality control. In recent years, artificial exosomes are emerging based on nanobiotechnology to overcome the limitations of natural exosomes. Major types of artificial exosomes include 'nanovesicles (NVs)', 'exosome-mimetic (EM)' and 'hybrid exosomes (HEs)', which are obtained by top-down, bottom-up and biohybrid strategies, respectively. Artificial exosomes are powerful alternatives to natural exosomes for drug delivery. Here, we outline recent advances in artificial exosomes through nanobiotechnology and discuss their strengths, limitations and future perspectives. The development of artificial exosomes holds great values for translational nanomedicine.

Calycosin-loaded nanoliposomes as potential nanoplatforms for treatment of diabetic nephropathy through regulation of mitochondrial respiratory function.

BACKGROUNDS: One of the most common complications in diabetic nephropathy is generation of high levels of ROS which can be regulated by herbal antioxidants. However, polyphenols like calycosin, the bioactive compound of Radix astragali suffer from low solubility and poor bioavailability. METHODS: Therefore, in the present study, calycosin-loaded nanoliposomes were fabricated and characterized by TEM, DLS and FTIR techniques. Afterwards, the drug loading (DL) and entrapment efficiency (EE), drug release, solubility, stability, and pharmacodynamic assays were performed. Finally, the antinephropathic effects of calycosin-loaded-nanoliposomes on mitochondria of kidney cells were explored by MTT, ROS, MDA, mitochondrial respiratory function assays. RESULTS: The result showed that the size, hydrodynamic radius, zeta potential, EE, and DL were, 80 nm, 133.99 ± 21.44 nm, - 20.53 ± 3.57, 88.37 ± 2.28%, and 7.48 ± 1.19%, respectively. The outcomes of in vitro release assay showed that calycosin-loaded nanoliposomes were significantly slow-release in dialysis media with pH 1.2, pH 6.9 and pH 7.4, at about 30 min, the dissolution of calycosin from nanoliposome became almost complete, and after 2 months, the calycosin-loaded nanoliposomes were still stable. Pharmacokinetic assay revealed that the AUC0-t of calycosin in calycosin-loaded nanoliposome group was 927.39 ± 124.91 µg/L*h, which was 2.26 times than that of the free calycosin group (**P < 0.01). Additionally, the MRT0-t and t1/2 of calycosin in the calycosin-loaded nanoliposome group were prolonged by 1.54 times and 1.33 times than that of free calycosin group, respectively (*P < 0.05). Finally, it was shown that calycosin-loaded nanoliposomes regulated the viability, ROS production, lipid peroxidation and function of mitochondria in kidney cells of diabetic rats as a model of diabetic nephropathy. CONCLUSION: In conclusion it may be suggested that new therapies based on nano-formulated calycosin can restore mitochondrial function which can improve diabetic nephropathy.

Organic Electrochemical Transistor for in Situ Detection of H2O2 Released from Adherent Cells and Its Application in Evaluating the In Vitro Cytotoxicity of Nanomaterial.

Detection of hydrogen peroxide (H2O2) produced by living cells is very significant to fully understand its roles in cellular physiology, as well as providing reliable diagnosis of pathological conditions. However, in situ detection of H2O2 released from adherent cells in cellular culture medium is still insufficiently achieved. Here, we report an electrochemical platform for in situ detection of H2O2 produced by adherent cells in cellular culture medium. It is based on the use of organic electrochemical transistor (OECT) fabricated on a flexible poly(ethylene terephthalate) substrate and Transwell support. A screen-printed carbon paste electrode was modified with carbon nanotubes and platinum nanoparticles and served as the gate of the device. Under optimal conditions, this device exhibits good modulation and sensitivity. It works in the 0.5 µM to 0.1 mM H2O2 concentration range and has a 0.2 µM detection limit. The cells were seeded and grew on the Transwell membrane. Upon being stimulated by N-formylmethionyl-leucyl-phenylalanine peptide, H2O2 produced by the adherent cells diffused into the bottom chamber of the Transwell and was in situ detected by OECT. Moreover, evaluating in vitro cytotoxicity of the nanomaterial using the OECT-Transwell platform was realized. This simple electrochemical platform would be of great interest for in vitro cytotoxicity, cellular physiology study, and diagnosis of pathological conditions.

Semi-solid extrusion 3D printing ODFs: an individual drug delivery system for small scale pharmacy.

Orodispersible films (ODFs) are promising drug delivery systems for customized medicines as it provide an alternative approach to increase consumer acceptance by advantages of rapid dissolution and administration without water. The aim of this study was to develop a platform to support the realization of tailored treatments suitable for the extemporaneous production of ODFs by semi-solid extrusion (SSE) 3D printing (3DP). Hydroxypropyl methyl cellulose (HPMC) was used as the polymer of ODFs, and levocetirizine hydrochloride was used as the model drug. The optimal formulation was HPMC:API:PS:maltitol:sucralose at a ratio of 64:10:10:15:1. Seventeen percent HPMC solution and optimal formulation were used to prepare film precursors. The impact of dynamic viscosities and fluid mechanics difference on printing applicability was discussed. The ODFs of cube designs with aimed dose of 1.25 mg, 2.5 mg, and 5 mg were printed by SSE 3DP. Good linear relationship between theoretical model volume and drug content (R2 = 0.999) and good dose accuracy indicate that 3DP is a suitable method for preparing individualized ODFs.

The fabrication of poly (polyethylene glycol diacrylate) monolithic porous layer open tubular (mono-PLOT) columns and applications in hydrophilic interaction chromatography and capillary gas chromatography for small molecules.

The easy shrinkage and swelling of polymer monolithic column when exposed to mobile phase with different polarity is a problem that cannot be ignored. To overcome this drawback, a convenient aqueous two-phase polymerization approach was used to prepare poly (polyethylene glycol diacrylate, PEGDA) monolithic porous layer open tubular (mono-PLOT) columns (150 µm). The poly(PEGDA) mono-PLOT column with homogeneous polymer porous layer was synthesized successfully. A maximum plate number of 41,500 plates per meter for allyl thiourea was obtained under a velocity of 1.8 mm/s. Several kinds of polar molecule were separated on the proposed mono-PLOT column and a typical hydrophilic interaction retention mechanism was observed. High speed separation of benzoic acids was also carried out, baseline separation of five benzoic acids was successfully achieved within 5 min with a 70 cm mono-PLOT column at 50°C. Furthermore, the resulting PLOT column was also successfully applied to separate standard analytes of three DNA oxidative damage products and RNA-modified nucleosides and four chlorophenols. At last, the column could separate alcohols, alkanes, and aromatic isomers via GC. It had more than 20,000 plates per meter for butanol - higher than commercial coatings open tubular columns.

A site-specific branching poly-glutamate tag mediates intracellular protein delivery by cationic lipids.

Intracellular protein delivery is of significance for cellular protein analysis and therapeutic development, but remains challenging technically. Herein, we report a general and highly potent strategy for intracellular protein delivery based on commercially available cationic lipids. In this strategy, a designed double branching poly-glutamate tag is site-specifically attached onto the C-terminal of protein cargos via expressed protein ligation (EPL), which mediates the entrapment of proteins into cationic liposomes driven by electrostatic interaction. The resultant protein-lipid complexes can enter into cytosol with a high efficiency even at the low protein concentration while maintaining protein's biological activity.

Oral disintegrating patient-tailored tablets of warfarin sodium produced by 3D printing.

Individualized medicine is a new direction in the field of modern pharmacy. In this study, we assessed the feasibility and accuracy of 3D printing techniques for the preparation of individualized doses of mouth-disintegrating tablets of warfarin. Warfarin sodium, D-sucrose, pregelatinized starch, povidone K30, microcrystalline cellulose, and silicon dioxide (at a ratio of 1:42.45:46.15:5.1:4.9:0.4) were mixed and used as the printing powder in the 3D printer; preset parameters were used. The dosage of the tablet was controlled by the number of printing layers. The content, dose uniformity, dose accuracy, hardness, friability, disintegration time, dissolution, and the microstructural and overall appearance were determined to evaluate the printed tablets. For the doses of 3, 2, and 1 mg that were produced in the experiment, the disintegration times were 50.0 ± 5.2, 35.7 ± 4.3, and 11.0 ± 2.2 s, respectively, and the relative errors of the dose were -2.33, -1.50, and 0%, respectively. The other indicators were consistent with the preparation requirements of pharmaceutical tablets. It is possible to prepare tablets with excellent properties and controlled drug doses by using 3D printing techniques. This technology will be an important means to achieve individualized medicine.

Vaccination with Toxoplasma gondii calcium-dependent protein kinase 6 and rhoptry protein 18 encapsulated in poly(lactide-co-glycolide) microspheres induces long-term protective immunity in mice.

BACKGROUND: Toxoplasmosis is a worldwide zoonosis caused by the intracellular parasite Toxoplasma gondii. However, no effective vaccine is yet available. Poly(lactide-co-glycolide) polymers can reduce protein degradation and sustain the release of antigens over a long period, which could generate a long-lasting immune response in vivo. Using a mouse model of toxoplasmosis, we evaluated the protective efficacy of vaccination with two recombinant proteins, which are formulated in biodegradable polymers. METHODS: Two recombinant proteins, rCDPK6 and rROP18, were encapsulated in poly(D,L-lactide-co-glycolide) (PLG), and then injected subcutaneously into Kunming mice. The mice immune responses were evaluated in terms of lympho-proliferation, cytokine expression, and antibodies. The survival of infected mice and brain cyst formation were also evaluated at 6 weeks after challenge with T. gondii RH strain (genotype I) or PRU strain (genotype II). RESULTS: Both protein vaccines induced Th1-biased immune responses, with increased specific antibodies and T cells, high levels of interferon-γ and interleukin 2, and strong lymphocyte proliferative responses. The mice immunized with the various protein vaccines survived slightly longer time than the control groups (P > 0.05) after injection with T. gondii RH strain. There were fewer brain cysts in the mice in all the immunized groups than that in the control groups, and the brain cysts were significantly reduced in mice immunized with proteins + 206, rCDPK6 + PLG and rCDPK6 + rROP18 + PLG (P < 0.05) compared controls. Further comparison of the immune responses to the proteins adjuvanted with PLG or Montanide™ ISA 206 VG 6 weeks after the last immunization revealed that antigens encapsulated in PLG conferred greater protective immunity against challenge. CONCLUSIONS: These findings suggest that the two recombinant T. gondii proteins encapsulated in PLG conferred immunity to T. gondii for an extended period, providing the foundation for the further development of a commercial vaccine against toxoplasmosis.

A review on micro- and nanoplastics in humans: Implication for their translocation of barriers and potential health effects.

As emerging contaminants, micro- and nanoplastics (MNPs) can absorb and leach various toxic chemicals and ultimately endanger the health of the ecological environment and humans. With extensive research on MNPs, knowledge about MNPs in humans, especially their translocation of barriers and potential health effects, is of utmost importance. In this review, we collected literature published from 2000 to 2023, focusing on MNPs on their occurrence in humans, penetrating characteristics in the placental, blood-brain, and blood-testis barriers, and exposure effects on mammalian health. The characteristics and distributions of MNPs in human samples were analyzed, and the results demonstrated that MNPs were ubiquitous in most human samples, except for kidneys and cerebrospinal fluid. In addition, the phenomenon of MNPs crossing barriers and their underlying mechanisms were discussed. We also summarized the potential factors that may affect the barrier crossing and health effects of MNPs, including characteristics of MNPs, exposure doses, administration routes, exposure durations, co-exposure to other pollutants, and genetic predisposition. Exposure to MNPs may cause cytotoxicity, neurotoxicity, and developmental and reproductive toxicity in mammals. People are encouraged to reduce their exposure to MNPs to prevent these adverse health effects. Finally, we discussed the shortcomings of current research on MNPs in humans, providing a valuable reference for understanding and evaluating the potential health risks from MNP exposure in mammals, including humans.

Low birth weight is associated with lower respiratory tract infections in children with hand, foot, and mouth disease.

BACKGROUND: Low birth weight (LBW) might be a risk factor for acquiring lower respiratory tract infections (LRTIs) associated with disease related complications in early childhood. HFMD, a frequent viral infection in southern China, is a leading cause of lower respiratory tract infections in children. We analyzed whether LBW is a risk factor for children with HFMD to develop lower respiratory tract infections. METHODS: A total of 298 children with HFMD, admitted to a hospital in Qingyuan city, Guangdong province, were recruited. Demographic data and clinical parameters such as serum glucose level and inflammatory markers including peripheral white blood cell count, serum C-reactive protein, and erythrocyte sedimentation rate were routinely collected on admission. Birth weight data were derived from birth records. RESULTS: Mean birth weight (BW) was 167 g lower in patients with HFMD and LRTIs as compared to patients with solely HFMD (p = 0.022) and the frequency of birth weight below the tenth percentile was significantly higher in patients with HFMD and LRTIs (p = 0.002). CONCLUSIONS: The results of the study show that low birth weight is associated with a higher incidence of lower respiratory tract infections in young children with HFMD.

Graphene and its derivatives: "one stone, three birds" strategy for orthopedic implant-associated infections.

Orthopedic implants provide an avascular surface for microbial attachment and biofilm formation, impeding the entry of immune cells and the diffusion of antibiotics. The above is an important cause of dental and orthopedic implant-associated infection (IAI). For the prevention and treatment of IAI, the drawbacks of antibiotic resistance and surgical treatment are increasingly apparent. Due to their outstanding biological properties such as biocompatibility, immunomodulatory effects, and antibacterial properties, graphene-based nanomaterials (GBNs) have been applied to bone tissue engineering to deal with IAI, and in particular have great potential application in drug/gene carriers, multi-functional platforms, and coating forms. Here we review the latest research progress and achievements in GBNs for the prevention and treatment of IAI, mainly including their biomedical applications for antibacterial and immunomodulation effects, and for inducing osteogenesis. Furthermore, the biosafety of graphene family materials in bone tissue regeneration and the feasibility of clinical application are critically analyzed and discussed.

MXene-Functionalized Ferroelectric Nanocomposite Membranes with Modulating Surface Potential Enhance Bone Regeneration.

Rapid and effective bone defect repair remains a challenging issue for clinical treatment. Applying biomaterials with endogenous surface potential has been widely studied to enhance bone regeneration, but how to regulate the electric potential and surface morphology of the implanted materials precisely to achieve an optimal bioelectric microenvironment is still a major challenge. The aim of this study is to develop electroactive biomaterials that better mimic the extracellular microenvironment for bone regeneration. Hence, MXene/polyvinylidene fluoride (MXene/PVDF) ferroelectric nanocomposite membranes were prepared by electrospinning. Physicochemical characterization demonstrated that Ti3C2Tx MXene nanosheets were wrapped in PVDF shell layer and the surface morphology and potential were modulated by altering the content of MXene, where uniform distribution of fibers and enhanced electric potential can be obtained and precisely assembled into a natural extracellular matrix (ECM) in bone tissue. Consequently, the MXene/PVDF membranes facilitated cell adhesion, stretching, and growth, showing good biocompatibility; meanwhile, their intrinsic electric potential promoted the recruitment of osteogenic cells and accelerated the differentiation of osteoblast. Furthermore, 1 wt % MXene/PVDF membrane with a suitable surface potential and better topographical structure for bone regeneration qualitatively and quantitatively promoted bone tissue formation in a rat calvarial bone defect after 4 and 8 weeks of healing. The fabricated MXene/PVDF ferroelectric nanocomposite membranes show a biomimetic microenvironment with a sustainable electric potential and optimal 3D topographical structure, providing an innovative and well-suited strategy for application in bone regeneration.

[Study on stability and cutaneous permeation kinetics in vitro of positive-ionized liposome gel containing paeonol].

OBJECTIVE: To prepare positive-ionized liposome gel containing paeonol and study its stability and cutaneous permeation kinetics in vitro. METHODS: Prepared the liposome gel by dispersion-ultrasonic and gridding method, and studied the stability with the impact factor experiments. Compared the permeation rate of liposome gel with conventional gel in vitro using the Franz-diffusion cell. RESULTS: Mean diameter of the liposome was (132.7 +/- 14.1) nm with Zeta potential of (+33.54 +/- 1.95) mV and mean entrapment efficiency of (73.04 +/- 1.24)% (n=3), and the content of paeonol was (3.17 +/- 0.13) mg/g (n=3). The liposome gel had a promising appearance. It was stable at the humidity and the room temperature while was sensitive at the light and the temperature from 40 degrees C to 60 degrees C. The cumulative penetration amounts of the liposome gel was higher than that of the conventional gel (P < 0.05). Its cutaneous penetration rate and cumulative amounts in skin were higher than those of the conventional gel (P < 0.05). CONCLUSION: The positive-ionized liposome gel containing paeonol is stable and feasibly prepared. It can enhance the cutaneous permeation efficiency and guarantee the persistent release rate.

Effect of solvents on the chiral recognition mechanisms of immobilized cellulose-based chiral stationary phase.

The effect of solvents on the enantioselectivities of four structurally similar chiral solutes with a cellulose derivative-based chiral stationary phase, Chiralpak IB, were studied using acetone (AC), 2-propanol (IPA), and tert-butanol (TBA) separately as polar modifiers. The enantioselectivities α of benzoin and methyl mandelate decrease with an increase in modifier concentration CM, whereas the enantioselectivity of pantolactone increased with increasing AC concentration. These results were attributed to the heterogeneous adsorption mechanisms of enantiomers. To interpret the dependence of enantioselectivity on modifier content, an enantioselectivity model based on a two-site adsorption model was proposed. The dependence of α on CM was inferred to be mainly due to the distinct modulating effects of modifier concentration on the two adsorption sites: the nonselective type-I site and enantioselective type-II site. The model fitted the benzoin data satisfactorily over a wide TBA concentration range. The retention factors as a function of TBA concentration were successfully deconvoluted for each site. With the use of the proposed model, it was inferred that the chiral recognitions of benzoin and methyl mandelate were mainly achieved by the presence of an aromatic group adjacent to the hydroxyl group. When using IPA and TBA separately as modifiers, the presence of an aromatic group adjacent to the ketone group mainly contributed to the nonselective π interactions and enantioselective steric interactions, respectively. These results, along with those of the modifier adsorption isotherms, determined using the perturbation method, as well as the retention behaviors of various achiral solutes, indicate that the molecular recognition mechanism of IB sorbent is highly sensitive to the adsorbate's molecular geometry. The molecular environment of the sorbent can be controlled using different modifiers, leading to distinct adsorption and retention mechanisms.

PDGF-BB exhibited therapeutic effects on rat model of bisphosphonate-related osteonecrosis of the jaw by enhancing angiogenesis and osteogenesis.

The mechanism and effective treatment of bisphosphonate-related osteonecrosis of the jaw (BRONJ) are still uncertain. Our previous study revealed that zoledronate (ZOL) preferentially inhibited osteoclasts formation and platelet-derived growth factor-BB (PDGF-BB) secretion, causing suppression of angiogenesis and osteogenesis in vitro. The present study aimed to elucidate whether PDGF-BB had therapeutic effects on rat model of BRONJ by enhancing angiogenesis and angiogenesis. Firstly, rat model of BRONJ was established by ZOL and dexamethasone administration, followed by teeth extraction. The occurrence of BRONJ was confirmed and detected dead bone formation by maxillae examination, micro-CT scan and HE staining (10/10). Compared to control rats (0/10), both angiogenesis and mature bone formation were suppressed in BRONJ-like rats, evidenced by enzyme-linked immunosorbent assay (ELISA) for VEGF (P < 0.01), immunohistochemistry of CD31 (P < 0.05) and OCN (P < 0.01). Moreover, in the early stage of bone healing, the number of preosteoclasts (P < 0.001) and PDGF-BB secretion (P < 0.05) were significantly decreased in bisphosphonates-treated rats, along with the declined numbers of microvessels (P < 0.05) and osteoblasts (P < 0.05). In vitro study, CCK8 assay, alizarin red S staining and western blot assay showed that mandible-derived bone marrow mesenchymal stem cells (BMMSCs) in BRONJ-like rats presented suppressed functions of proliferation, osteogenesis and angiogenesis. Interestingly, recombinant PDGF-BB was able to rescue the impaired functions of BMMSCs derived from BRONJ-like rats at more than 10 ng/ml. Then fibrin sealant with or without recombinant PDGF-BB were tamped into the socket after debridement in BRONJ rats. After 8 weeks, fibrin sealant containing PDGF-BB showed significant therapeutic effects on BRONJ-like rats (bone healing: 8/10 vs 3/10, P < 0.05) with enhancing microvessels and mature bone formation. Our study suggested that the inhibition of angiogenesis and osteogenesis, the potential mechanisms of BRONJ, might partly result from suppression of PDGF-BB secretion in the early stage of bone healing. PDGF-BB local treatment after debridement might avail the healing of BRONJ by increasing angiogenesis and osteogenesis.

Effects of bone cement filling in rabbit proximal femoral medullary cavity on distal femoral blood flow and metabolism.

OBJECTIVE: A rabbit model was used to evaluate the effects of bone-cemented hip arthroplasty on distal femoral blood flow and metabolism relative to that of the non-cemented contralateral leg. METHODS: The marrow cavity of the right hind femur was filled with bone cement. At each of the following time points, rabbits were randomly selected to receive an injection of one dose of 99mTc-methylene diphosphonate and then immediately scanned using a gamma camera: immediately postoperatively and at 4 and 8 weeks postoperatively. A BL-410 model biofunction experimental system was used to analyze the acquired images and determine the radioactive counts of each hind leg. RESULTS: The X-ray and photographic images of the right femoral bones confirmed successful filling of the marrow cavity with bone cement. The radioactive counts were significantly lower in the experimental than control legs at each time point. The ratio of the radioactive count of the experimental to control leg increased considerably at each time point, but each ratio was <1. CONCLUSION: Blocking the proximal femoral medullary cavity with bone cement was associated with significant lowering of the blood circulation of the femur and marrow, decreasing the distal femoral blood flow and bone metabolic rate.

[Forensic identification of floating shoulder injury].

OBJECTIVE: To discuss forensic identification of floating shoulder injury (FSI). METHODS: To analyze fifteen cases of FSI which were accepted from Jan. 1993 to Jan. 2006, including 15 shoulder neck fracture, 13 clavide stem fracture and 2 distal end clavide fracture, the function of shoulder joint was evaluated six months after injure considering the following three aspects: result of forensic examination such as X-ray photograph, CT and MRI, the injurers' symptom, objective sign and joint function, shoulder joint territory, degree of pain and local muscle power. RESULTS: Basing on the curative effect standard of Herscovic, all cases were divided into good. Modest, worst, which included 2, 4, 9 cases respectively; referring the standard of GA35-92, GB18667-2002, all cases were divided into six, seven, eight, nine and ten degree, which included 2,9,2,1,1 cases respectively. CONCLUSION: As a special powerful injure, FSI always companied with concurrent and multiple injure, and characterized by missed, incorrect and delayed diagnosis and infelicitous treatment, which lead to the high frequency and degree of injure. To prevent missed and incorrect forensic identification, we should have a full realization of the particularity of FSI, and evaluate the function of shoulder all-sidely, objectively and synseticaly.

Surgical Management of Adult Reducible Atlantoaxial Dislocation, Basilar Invagination and Chiari Malformation with Syringomyelia.

AIM: To analyze retrospectively the surgical management of reducible atlantoaxial dislocation (AAD), basilar invagination (BI) and Chiari malformation (CHM) with syringomyelia through a single-stage posterior approach. MATERIAL AND METHODS: Forty-three patients with reducible AAD, BI and CHM with syringomyelia underwent surgery from January 2009 to January 2013. Intraoperative restoration followed by posterior decompression and plate-rod placement with occipital cortical screws and C2/C3 lateral mass cortical screws fixation devices were used in all patients. Results were recorded both pre- and postoperatively and these outcome measures included Nurick grading (NG) and radiology findings (atlantodental interval (ADI), space available for the spinal cord (SAC), interval between odontoid and Chamberlain's line (IOC), and the cervicomedullary angle (CMA)). RESULTS: Forty (93%) of the 43 patients were followed up. Thirty-six (90%) patients' symptoms improved and four (10%) stabilized. No patients became progressively worse. The difference between preoperative and postoperative Nurick grades was statistically significant. All patients achieved restoration, including thirty (75%) patients had full restoration and ten (25%) had part restoration. The size of syringomyelia was obviously decreased in 32 (80%) patients and stable in 8 (20%) patients. All radiology findings (ADI, IOC, SAC, CMA) showed significant changes from pre- to postoperative (p < 0.01). CONCLUSION: Intraoperative distraction, extension combined posterior decompression with use of plate-rod-screws occipitocervical fusion device is an effective method to treat AAD, BI and CHM with syringomyelia.