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1.
J Neurol Surg A Cent Eur Neurosurg ; 83(3): 231-235, 2022 May.
Article in English | MEDLINE | ID: mdl-34192784

ABSTRACT

OBJECTIVE: Posterior subaxial cervical screw fixation is commonly performed using the cervical pedicle screws (CPS) and lateral mass screws (LMS); however, their compatibility is low. Modified lateral mass screws (mLMS, also called paravertebral foramen screw) fixation was introduced as a salvage technique for LMS fixation and has features of both LMS and CPS techniques. In the present study, the use of mLMS as an alternative to CPS was analyzed based on clinical results. METHODS: Seventy-eight screws (38 CPSs and 40 mLMSs) were inserted into 12 patients. The misplacement of the screws was evaluated by computed tomography (CT). The failure of instrumentation and instability were evaluated using plain radiographs. RESULTS: The total number of CPS misplacements was 3 (10.5%); however, neurologic complications were not observed. mLMSs were used in the middle segments of the fusion in 10 patients and 2 patients had mLMS fixation for single-level fusion. An additional bridging implant was not required for connecting both CPSs and mLMSs. Instability was not observed during the observation period (4-51 months). Complete fusion was seen in 10 patients. CONCLUSIONS: The alternative mLMS fixation can decrease the risk of screw misplacement compared with CPS fixation alone and achieves adequate stability leading to fusion.


Subject(s)
Pedicle Screws , Spinal Fusion , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Humans , Spinal Fusion/methods , Tomography, X-Ray Computed
2.
Tissue Eng Regen Med ; 19(1): 105-116, 2022 02.
Article in English | MEDLINE | ID: mdl-34626334

ABSTRACT

BACKGROUND: Hair follicles are among a handful of organs that exhibit immune privilege. Dysfunction of the hair follicle immune system underlies the development of inflammatory diseases, such as alopecia areata. METHODS: Quantitative reverse transcription PCR and immunostaining was used to confirm the expression of major histocompatibility complex class I in human dermal papilla cells. Through transcriptomic analyses of human keratinocyte stem cells, major histocompatibility complex class I was identified as differentially expressed genes. Organ culture and patch assay were performed to assess the ability of WNT3a conditioned media to rescue immune privilege. Lastly, CD8+ T cells were detected near the hair bulb in alopecia areata patients through immunohistochemistry. RESULTS: Inflammatory factors such as tumor necrosis factor alpha and interferon gamma were verified to induce the expression of major histocompatibility complex class I proteins in dermal papilla cells. Additionally, loss of immune privilege of hair follicles was rescued following treatment with conditioned media from outer root sheath cells. Transcriptomic analyses found 58 up-regulated genes and 183 down-regulated genes related in MHC class I+ cells. Using newborn hair patch assay, we demonstrated that WNT3a conditioned media with epidermal growth factor can restore hair growth. In alopecia areata patients, CD8+ T cells were increased during the transition from mid-anagen to late catagen. CONCLUSION: Identification of mechanisms governing epithelial and mesenchymal interactions of the hair follicle facilitates an improved understanding of the regulation of hair follicle immune privilege.


Subject(s)
Alopecia Areata , Immune Privilege , Alopecia Areata/metabolism , Alopecia Areata/therapy , Epidermal Growth Factor/metabolism , Hair Follicle/metabolism , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/metabolism , Humans , Infant, Newborn
3.
Nature ; 597(7876): 393-397, 2021 09.
Article in English | MEDLINE | ID: mdl-34433967

ABSTRACT

Cellular dynamics and fate decision in early human embryogenesis remain largely unknown owing to the challenges of performing studies in human embryos1. Here, we explored whole-genomes of 334 single-cell colonies and targeted deep sequences of 379 bulk tissues obtained from various anatomical locations of seven recently deceased adult human donors. Using somatic mutations as an intrinsic barcode, we reconstructed early cellular phylogenies that demonstrate (1) an endogenous mutational rate that is higher in the first cell division but decreases to approximately one per cell per cell division later in life; (2) universal unequal contribution of early cells to embryo proper, resulting from early cellular bottlenecks that stochastically set aside epiblast cells within the embryo; (3) examples of varying degrees of early clonal imbalances between tissues on the left and right sides of the body, different germ layers and specific anatomical parts and organs; (4) emergence of a few ancestral cells that will substantially contribute to adult cell pools in blood and liver; and (5) presence of mitochondrial DNA heteroplasmy in the fertilized egg. Our approach also provides insights into the age-related mutational processes and loss of sex chromosomes in normal somatic cells. In sum, this study provides a foundation for future studies to complete cellular phylogenies in human embryogenesis.


Subject(s)
Cell Lineage/genetics , Clone Cells/metabolism , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Embryonic Development/genetics , Mutation , DNA, Mitochondrial/genetics , Embryo, Mammalian/embryology , Female , Humans , Male , Mutation Rate
4.
Clin Neuroradiol ; 30(1): 171, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32034460

ABSTRACT

Correction to: Clin Neuroradiol 2019 https://doi.org/10.1007/s00062-019-00793-1The original version of this article unfortunately contained some mistakes. The Institutional Review Board number was given wrongly in the Methods/Participants section and in the Compliance with ethical guidelines/Ethical.

5.
Clin Neuroradiol ; 30(1): 159-169, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31123775

ABSTRACT

PURPOSE: To investigate the long-term outcome of stent angioplasty for symptomatic severe intracranial artery stenosis. METHOD: In this study 95 consecutive patients with intracranial atherosclerotic stenosis (>70%) underwent stent angioplasty using Wingspan stents. The primary endpoints were stroke or death within 30 days of the procedure and subsequent stroke attributed to the stented vessel. Disabling stroke was defined as stroke with a modified Rankin scale > 3. Secondary endpoints included transient ischemic attacks, contralateral stroke, nonstroke death, and other events. Patients underwent prestent balloon dilation with or without poststent balloon dilation, close restenosis follow-up, and selective retreatment, as required. RESULT: The mean follow-up duration was 34.9 ± 23.3 months. Primary endpoint events occurred in 23% of the patients. The median infarction volume was 2.6 ml, and 11 (68%) of 16 infarctions were <5 ml in volume. Disabling stroke occurred in 3% of patients. The primary endpoint rates were 17.9% within 30 days and 2.1% from 30 days to 1 year. Secondary endpoint events occurred in 27.3% of the patients. Mean stenosis was reduced from 76.8 ± 6.1% to 7.5 ± 13.4%. Of 80 patients who underwent angiographic follow-up, 11 (14%) experienced restenosis (≥50%) and 7 (9%) exhibited restenosis-related symptoms of transient ischemic attack. The rate of symptomatic restenosis was significantly higher in patients who underwent prestent balloon dilation alone than in patients who underwent prestent and poststent balloon dilation (p = 0.016). CONCLUSION: The postprocedural stroke rate was similar to that observed in the SAMMPRIS study. Symptomatic restenosis may be reduced by poststent dilation, close angiographic follow-up, and retreatment.


Subject(s)
Angioplasty/instrumentation , Angioplasty/methods , Graft Occlusion, Vascular/prevention & control , Intracranial Arteriosclerosis/surgery , Stents , Aged , Aged, 80 and over , Angioplasty, Balloon , Cerebral Arteries/diagnostic imaging , Cerebral Arteries/surgery , Computed Tomography Angiography , Diffusion Magnetic Resonance Imaging , Equipment Design , Female , Humans , Intracranial Arteriosclerosis/diagnostic imaging , Magnetic Resonance Angiography , Male , Middle Aged , Time , Treatment Outcome
6.
PLoS One ; 14(7): e0219119, 2019.
Article in English | MEDLINE | ID: mdl-31318904

ABSTRACT

Thus far, anatomical studies have reported data on the cervical pedicle, with the focus remaining on the pedicle itself. It was necessary to obtain more comprehensive data about the relationships between the lateral mass, pedicle, and transverse foramen for cervical pedicle screwing (CPS) and paravertebral foramen screwing (PVFS), a new technique. The purpose of this study was to describe the relationships between the lateral mass, pedicle, and transverse foramen. This study analyzed computed tomography images from 77 patients (42 female, 35 male; mean age: 63.95 years). The anatomical pedicle transverse angle (PTA) and linear parameters of the lateral mass were measured, and the relationship between the calculated angles and the anatomical PTA was investigated. θp was defined as the convergence angle from the posterolateral edge of the lateral mass to the pedicle, and θc was defined as the convergence angle from the posterolateral edge of the lateral mass to the anterolateral corner of the vertebral foramen. The thickness of the cortical bone of the medial wall of the lateral mass (cT) and the medial (mT) and lateral (lT) walls of the pedicle at C3-7 were also measured. The PTA was similar to θp and θc at C3-6, but different at C7. In all cases, the transverse foramen was located more anterior to the posterior wall of the cervical body at C3-6, but not at C7. mT and cT were significantly thicker than lT at all levels. Lateral fluoroscopic images show that when the probe is inserted along θc, it meets the counter corner of the lateral mass at C3-6 without invasion of the transverse foramen if it does not cross the posterior wall of the vertebral body. This can be significant when performing CPS and PVFS.


Subject(s)
Cervical Vertebrae/surgery , Pedicle Screws , Aged , Cervical Vertebrae/anatomy & histology , Cervical Vertebrae/diagnostic imaging , Female , Humans , Male , Middle Aged , Models, Anatomic , Spinal Diseases/diagnostic imaging , Spinal Diseases/surgery , Tomography, X-Ray Computed
7.
J Orthop Res ; 36(1): 217-223, 2018 01.
Article in English | MEDLINE | ID: mdl-28621468

ABSTRACT

This study aimed to report the mechanical strength and characteristics of the lateral mass and pedicle considering BMD for the safe insertion of pedicle screws in the subaxial cervical level. We evaluated BMD and Hounsfield unit (HU) values of cortical bones at the lateral mass and pedicle of C3-7 from CT images in 99 patients. Patients were divided into three groups (Group A, T-score ≥ -1; Group B, -2.5 < T-score < -1.0; Group C, T-score ≤ -2.5). The HU numbers of cortical bone in the vertebral canal (medial wall of the lateral mass; cHU), posterior wall of the transverse foramen (fHU), and medial wall, lateral wall, and trabecular area of the pedicle (mHU, lHU, and pHU, respectively) were measured on the CT images in the middle of the pedicle. A mechanical study was also performed to measure cortical bone strength using 10 fresh cadavers. The cHU and mHU values in Group C were higher than lHU and fHU in Groups A and B, and there was a wide gap between the pHU value and other areas. The penetrating force also had a close correlation with HU number. The mean penetrating force of the medial wall of the lateral mass and the posterior wall of the transverse foramen were 210.08 ± 110.46 and 50.51 ± 46.09 N, respectively. The cortical bones in the vertebral canal and medial wall of the pedicle were stronger than the lateral wall and the trabecular area. The cHU and mHU in the osteoporotic group were higher than fHU and pHU in the normal group. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:217-223, 2018.


Subject(s)
Bone Density , Cervical Vertebrae/surgery , Pedicle Screws , Adult , Aged , Aged, 80 and over , Biomechanical Phenomena , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/physiology , Cortical Bone/diagnostic imaging , Cortical Bone/physiology , Female , Humans , Male , Middle Aged , Tomography, X-Ray Computed
8.
Elife ; 62017 07 11.
Article in English | MEDLINE | ID: mdl-28695824

ABSTRACT

The control principles behind robust cyclic regeneration of hair follicles (HFs) remain unclear. Using multi-scale modeling, we show that coupling inhibitors and activators with physical growth of HFs is sufficient to drive periodicity and excitability of hair regeneration. Model simulations and experimental data reveal that mouse skin behaves as a heterogeneous regenerative field, composed of anatomical domains where HFs have distinct cycling dynamics. Interactions between fast-cycling chin and ventral HFs and slow-cycling dorsal HFs produce bilaterally symmetric patterns. Ear skin behaves as a hyper-refractory domain with HFs in extended rest phase. Such hyper-refractivity relates to high levels of BMP ligands and WNT antagonists, in part expressed by ear-specific cartilage and muscle. Hair growth stops at the boundaries with hyper-refractory ears and anatomically discontinuous eyelids, generating wave-breaking effects. We posit that similar mechanisms for coupled regeneration with dominant activator, hyper-refractory, and wave-breaker regions can operate in other actively renewing organs.


Subject(s)
Hair Follicle/physiology , Hair/growth & development , Animals , Mice , Models, Biological , Regeneration , Spatio-Temporal Analysis
9.
J Invest Dermatol ; 136(1): 34-44, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26763421

ABSTRACT

Hair follicles (HFs) undergo lifelong cyclical transformations, progressing through stages of rapid growth (anagen), regression (catagen), and relative "quiescence" (telogen). Given that HF cycling abnormalities underlie many human hair growth disorders, the accurate classification of individual cycle stages within skin biopsies is clinically important and essential for hair research. For preclinical human hair research purposes, human scalp skin can be xenografted onto immunocompromised mice to study human HF cycling and manipulate long-lasting anagen in vivo. Although available for mice, a comprehensive guide on how to recognize different human hair cycle stages in vivo is lacking. In this article, we present such a guide, which uses objective, well-defined, and reproducible criteria, and integrates simple morphological indicators with advanced, (immuno)-histochemical markers. This guide also characterizes human HF cycling in xenografts and highlights the utility of this model for in vivo hair research. Detailed schematic drawings and representative micrographs provide examples of how best to identify human HF stages, even in suboptimally sectioned tissue, and practical recommendations are given for designing human-on-mouse hair cycle experiments. Thus, this guide seeks to offer a benchmark for human hair cycle stage classification, for both hair research experts and newcomers to the field.


Subject(s)
Cell Cycle/physiology , Hair Follicle/growth & development , Hair/physiology , Animals , Apoptosis/physiology , Biopsy, Needle , Cells, Cultured , Guidelines as Topic , Hair Follicle/anatomy & histology , Heterografts , Humans , Immunohistochemistry , Mice , Mice, SCID
10.
Spine (Phila Pa 1976) ; 40(15): 1181-6, 2015 Aug 01.
Article in English | MEDLINE | ID: mdl-25996541

ABSTRACT

STUDY DESIGN: Cadaver study and clinical application; a pilot study. OBJECTIVE: To minimize muscle dissection and enhance accuracy of cervical pedicle screw (CPS) placement by using a percutaneous cannula system. SUMMARY OF BACKGROUND DATA: Many studies have reported that the most frequent misplacement of CPSs is breach of the lateral wall; thus, an easy technique for securing medial convergence is required. We developed a percutaneous cannula system for this purpose and report the results of a cadaver study and its clinical application. METHODS: A cadaver study was conducted to confirm the possibility of this percutaneous technique in 5 specimens (50 CPSs, C3-C7). Then, the technique was applied in 8 patients (40 CPSs, C3-C7). The surgical technique was a hybrid of miniopen surgery and the use of percutaneous cannula system under lateral fluoroscopic guidance. Entry holes were made in the open field and a cannula was used for tapping and insertion of CPSs. A stiff pedicle probe through the cannula was used to locate the pedicle in the lateral mass. RESULTS: In the cadaver study, there were 12 (24%) misplacements among 50 CPSs used. The hybrid technique was applied clinically in 4 traumatic, 2 degenerative, and 2 failed back surgery lesions. Thirty CPSs were inserted using the percutaneous cannula system and 10 were inserted using a cannula as a retractor. Misplacement occurred in 6.7% (n = 2) and 20% (n = 2) pedicles, respectively, and there were no symptomatic complications (total incidence, 10%). An additional incision for the cannula system can be made for 2-level CPS insertions. CONCLUSION: Use of the percutaneous cannula system facilitated a secure convergence angle for CPS insertion without extending muscle dissection or shifting cervical alignment because of muscle retraction. Moreover, this system can be used for CPS insertion in bull-necked patients. LEVEL OF EVIDENCE: 3.


Subject(s)
Bone Screws , Cervical Vertebrae/surgery , Orthopedic Procedures/instrumentation , Orthopedic Procedures/methods , Back Injuries/surgery , Cadaver , Catheters , Female , Humans , Male , Minimally Invasive Surgical Procedures/instrumentation , Pilot Projects , Spinal Diseases/surgery
11.
J Korean Neurosurg Soc ; 54(1): 25-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-24044076

ABSTRACT

OBJECTIVE: To clarify the landmark for deciding the entry point for C1 lateral mass screws via the posterior arch by using 3-dimensional (3D) computed images. METHODS: Resnick insisted that the C1 posterior arch could be divided into pure posterior and lateral lamina (C1 pedicle). Authors studied where this transition point (TP) is located between the posterior lamina and the C1 pedicle and how it can be recognized. The 3D computed images of 86 cadaver C1s (M : F=45 : 41) were used in this study. RESULTS: The superior ridge of the C1 posterior arch had 2 types of orientation. One was in the vertical direction in the C1 posterior lamina and the other was in the horizontal direction in the C1 pedicle. The TP was located at the border between the 2 areas, the same site as the posterior end of the groove of the vertebral artery. On posterior-anterior projection, the posterior arch was sharpened abruptly at TP. We were unable to identify the TP in 6.4% of specimens due to complete or partial osseous bridges. A total of 93.8% of the TP were located between the most enlarged point of the spinal canal and the medial wall of the vertebral artery. CONCLUSION: The anatomic entry zone of C1 lateral laminar screws was clarified and identified based on the TP by using preoperative 3D computed images.

12.
J Cerebrovasc Endovasc Neurosurg ; 15(2): 85-95, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23844352

ABSTRACT

OBJECTIVE: The purpose of this study is to investigate the results of treatment using stent-angioplasty for symptomatic middle cerebral arterial (MCA) stenosis and comparison of in-stent restenosis between drug-eluting stents (DES), bare metal coronary stents (BMS) and self-expanding stents (SES). MATERIALS AND METHODS: From Jan. 2007 to June. 2012, 34 patients (mean age ± standard deviation: 62.9 ± 13.6 years) with MCA stenosis were treated. Inclusion criteria were acute infarction or transient ischemic attacks (TIAs) and angiographically proven symptom related severe stenosis. Stents used for treatment were DES (n = 8), BMS (n = 13) and SES (n = 13). National Institutes of Health Stroke Scale (NIHSS) at admission was 2.5 ± 3.1 and mean stenosis rate was 79.0 ± 8.2%. Assessment of clinical and angiographic results was performed retrospectively. RESULTS: Among 34 patients, periprocedural complications occurred in four cases (11.8%), however, only two cases (6.0%) were symptomatic. All patients were followed clinically (mean follow-up period; 40.7 ± 17.7 months) and 31 were followed angiographically (91.2%. 13.4 ± 8.5 months). There was no occurrence of repeat stroke in all patients; however, mild TIAs related to restenosis occurred in three of 34 patients (8.8%). The mean NIHSS after stent-angioplasty was 1.7 ± 2.9 and 0.8 ± 1.1 at discharge. The modified Rankin score (mRS) at discharge was 0.5 ± 0.9 and 0.3 ± 0.8 at the last clinical follow-up. In-stent restenosis over 50% occurred in five of 31 angiographically followed cases (16.1%), however, all of these events occurred only in patients who were treated with BMS or SES. Restenosis rate was 0.0% in the DES group and 20.8% in the other group (p = 0.562); it did not differ between BMS and SES (2/11 18.2%, 3/13 23.1%, p = 1.000). CONCLUSION: Stent-angioplasty appears to be effective for symptomatic MCA stenosis. As for restenosis, in our study, DES was presumed to be more effective than BMS and SES; meanwhile, the results did not differ between the BMS and SES groups.

13.
J Korean Neurosurg Soc ; 49(5): 273-7, 2011 May.
Article in English | MEDLINE | ID: mdl-21716899

ABSTRACT

OBJECTIVE: A single balloon extrapedicular kyphoplasty has been introduced as one of the unilateral approaches for thoracic compression fractures; however, the unilateral extrapedicular technique in the lumbar area needs a further understanding of structures in the lumbar area. The purpose of the present study is to describe methods and pitfalls of this procedure based on the anatomy of the lumbar area and to analyze clinical outcome and complications. METHODS: Anatomical evaluation was performed with 2 human cadavers. A retrospective review of unilateral extrapedicular approaches yielded 74 vertebral levels in 55 patients that were treated with unilateral extrapedicular vertebroplasty and kyphoplasty. Radiographic assessment included the restoration rate of vertebral height and correction of kyphosis. RESULTS: Anatomical evaluation indicates that the safe needle entry zone of bone for the extrapedicular approach was located in the supero-lateral aspect of the junction between the pedicle and vertebral body. The unilateral extrapedicular procedure achieved adequate pain relief with a mean decreases in pain severity of 7.25±1.5 and 2.0±1.4, respectively. Complications were 1 retroperitoneal hematoma, 6 unilateral fillings and 3 epidural leak of the polymethylmethacrylate. CONCLUSION: The method of a unilateral extrapedicular approach in kyphoplasty and vertebroplasty in the lumbar area might be similar to that in thoracic approach using a route via the extrapedicular space. However, different anatomical characteristics of the lumbar area should be considered.

14.
J Korean Neurosurg Soc ; 48(1): 59-61, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20717513

ABSTRACT

Neurocysticercosis is the most common parasitic disease of the central nervous system in humans, caused by infection of the larval stage of the pork tapeworm, Taenia solium. However, cerebellar involvement is rarely reported. We report of a case of racemose cysticercosis in the cerebellar hemisphere. A 44-year-old man presented with headache and dizziness. Magnetic resonance imaging showed hydrocephalus and an ill-defined, multicystic cerebellar mass with hypersignal on T2-weighted images, hyposignal on T1-weighted images and rim enhancement after gadolinium injection. The patient underwent endoscopic third ventriculostomy and the cyst resection was done through a craniotomy. In surgical field, cysts were conglomerated in a dense collagen capsule that were severely adherent to surrounding cerebellar tissue, and transparent cysts contained white, milky fluid. Histological findings confirmed the diagnosis of cysticercosis. He received antiparasitic therapy with praziquantel after surgery. Racemose cysticercosis is rare in the cerebellar hemisphere but neurocysticercosis should be taken into consideration as a differential diagnosis of multiple cystic lesions in the cerebellum.

15.
J Korean Neurosurg Soc ; 47(4): 252-7, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20461164

ABSTRACT

OBJECTIVE: Barbiturate coma therapy (BCT) is a useful method to control increased intracranial pressure (IICP) patients. However, the complications such as hypotension and hypokalemia have caused conditions that stopped BCT early. The complications of low dose BCT with Bispectral index (BIS) monitoring and those of high dose BCT without BIS monitoring have been compared to evaluate the efficacy of low dose BCT with BIS monitoring. METHODS: We analyzed 39 patients with high dose BCT group (21 patients) and low dose BCT group (18 patients). Because BIS value of 40-60 is general anesthesia score, we have adjusted the target dose of thiopental to maintain the BIS score of 40-60. Therefore, dose of thiopental was kept 1.3 to 2.6 mg/kg/hour during low dose BCT. However, high dose BCT consisted of 5 mg/kg/hour without BIS monitoing. RESULTS: The protocol of BCT was successful in 72.2% and 38.1% of low dose and high dose BCT groups, respectively. The complications such as QT prolongation, hypotension and cardiac arrest have caused conditions that stopped BCT early. Hypokalemia showed the highest incidence rate in complications of both BCT. The descent in potassium level were 0.63 +/- 0.26 in low dose group, and 1.31 +/- 0.48 in high dose group. The treatment durations were 4.89 +/- 1.68 days and 3.38 +/- 1.24 days in low dose BCT and high dose BCT, respectively. CONCLUSION: It was proved that low dose BCT showed less severe complications than high dose BCT. Low dose BCT with BIS monitoring provided enough duration of BCT possible to control ICP.

16.
Spine (Phila Pa 1976) ; 35(10): 1026-32, 2010 May 01.
Article in English | MEDLINE | ID: mdl-20393396

ABSTRACT

STUDY DESIGN: A descriptive cadaveric study measuring arterial tension. OBJECTIVE: Anterior lumbar surgery is technically challenging due to perioperative vascular complications. Many studies suggest approaches based on the anatomy of the abdominal vessel for safe vascular mobilization. However, the tension in the vascular structure is also important for adequate exposure of the target lesion. It has been established that the tension in the lumbar nerve at the root level can be changed by a straight leg raise test and that the structure of the vascular connection is similar to that of the neural connection. Consequently, a change in leg position could affect the tension of lumbosacral vessels. The purpose of this study was to evaluate the effect of leg position on the tension of lumbosacral vessels. METHODS: We dissected 10 unembalmed cadavers using the method described by Gumbs et al, using the Synframe system to expose the abdominal artery and vein. The left iliac artery and the distal abdominal aorta were retracted to the right side at the L4-L5 disc level by a measuring retractor to which a strain gauge was attached. The tension was checked at various angles of the hip joint and the motions of the abdominal arteries were monitored in 4 unembalmed cadavers using a C-arm fluoroscope. RESULTS: The tension in the abdominal aorta at L4-L5 level was decreased by 2.9% to 21.8% in the hip-flexion position, and the motion of the arteries showed proximal displacement of the external iliac artery and the common iliac artery during the hip-flexed position and veins also showed the same pattern of displacement as artery. CONCLUSION: The results of this study would be useful for not only spinal surgery but also other vascular surgeries, particularly, in cases where patients with conditions such as atherosclerosis or stenosis.


Subject(s)
Aorta, Abdominal/physiology , Iliac Artery/physiology , Leg/physiology , Lumbar Vertebrae/surgery , Patient Positioning/methods , Range of Motion, Articular/physiology , Abdominal Cavity/anatomy & histology , Abdominal Cavity/surgery , Adult , Aged , Aorta, Abdominal/anatomy & histology , Aorta, Abdominal/surgery , Biomechanical Phenomena/physiology , Cadaver , Female , Hip/anatomy & histology , Hip/physiology , Hip Joint/anatomy & histology , Hip Joint/physiology , Humans , Iliac Artery/anatomy & histology , Iliac Artery/surgery , Leg/anatomy & histology , Male , Middle Aged , Models, Anatomic , Neurosurgical Procedures/methods , Neurosurgical Procedures/standards , Patient Positioning/adverse effects , Patient Positioning/standards , Posture/physiology , Stress, Mechanical , Tensile Strength/physiology
17.
Eur Spine J ; 19(5): 828-32, 2010 May.
Article in English | MEDLINE | ID: mdl-20174836

ABSTRACT

This paper reports a morphometric study of the C2 laminae to provide quantitative anatomical data for safe crossing laminar screw placement. A valid trajectory is essential for C2 crossing laminar screw placement. Although several clinical technique notes and modifications to define a safe screw trajectory have been introduced in the recent years, no morphometric analysis has been performed to confirm the accuracy of screw trajectory using this technique. In this study, morphometric analysis was performed on 100 Korean C2 three-dimensional reconstruction CT images. The reconstructive C2 vertebrae from the post-edge of the spinal canal to the spinal process were divided into several zones, 1 mm each. Each zone was chosen as the entry point to imitate a crossing laminar screw (3.5 mm diameter) placement. In each 1-mm zoned trajectory, the screw pass ratio (PR), safe screw angle range (SAR) and maximum screw length (MSL) were measured and compared with the data from the other zoned trajectories. The zone '5-6 mm posterior to the post-edge of the spinal canal' was found to be a more feasible and safer entry point for guiding a crossing laminar screw placement than the other zones because this zone could provide a trajectory with maximal PR (85%), SAR (9.57 +/- 4.36 masculine) and a larger MSL (21.74 +/- 2.44 mm) than the other areas. The recommended safe screw angle in the axial plane is 49.68 +/- 4.94 to 59.19 +/- 4.70 masculine. However, the screw angle can vary considerably according to the individual variance. A preoperative evaluation of the screw trajectory is essential for safe screw placement using this technique.


Subject(s)
Bone Screws , Cervical Vertebrae/diagnostic imaging , Orthopedic Procedures/instrumentation , Adult , Cervical Vertebrae/surgery , Computer Simulation , Female , Humans , Image Processing, Computer-Assisted , Imaging, Three-Dimensional , Male , Middle Aged , Models, Anatomic , Orthopedic Procedures/methods , Radiography
18.
Proteomics ; 9(19): 4445-56, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19688726

ABSTRACT

Transforming growth factor-beta1 (TGF-beta1) has a wide range of biological functions such as the regulation of cell growth, differentiation, and immunological response in various types of cells. Particularly, TGF-beta1 induces plasminogen activator inhibitor-1 (PAI-1) as a major target protein. PAI-1 is associated with fibrosis, thrombosis, and metabolic disorders. In this study, to identify proteins potentially involved in TGF-beta1-induced fibrosis processes, we performed a proteomic analysis of TGF-beta1-induced normal rat kidney cells exposed to ascofuranone (AF). In these cells, we detected 1500 proteins, with 74 differentially expressed proteins identified by MALDI-TOF and reference to the NCBI and Swiss-Prot databases, including PAI-1, peroxisome prdifesator-activated receptor, prohibitin, glutamate formyltransferase, LIM domain protein 1, LASP-1, porphobilinogen deaminase, and peroxiredoxin 2. We also found that AF suppresses expression of profibrotic factors induced by TGF-beta in renal fibroblasts, including matrix proteins and PAI-1. AF was also shown to inhibit selectively phosphorylation of epidermal growth factor receptor, and downstream kinases such as extracellular signal-regulated kinase 1/2 (ERK-1/2). Further ongoing analysis of fibrosis-related proteins will determine AF's potential for application in fibrotic diseases and therapeutics.


Subject(s)
Fibroblasts , Kidney , Proteome/analysis , Sesquiterpenes/pharmacology , Transforming Growth Factor beta1/metabolism , Animals , Cell Line , Electrophoresis, Gel, Two-Dimensional , Enzyme Inhibitors/metabolism , ErbB Receptors/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Fibrosis/metabolism , Fibrosis/pathology , Kidney/cytology , Kidney/drug effects , Kidney/pathology , MAP Kinase Kinase Kinases/metabolism , Molecular Sequence Data , Molecular Structure , Plasminogen Activator Inhibitor 1/metabolism , Rats , Sesquiterpenes/chemistry , Signal Transduction/physiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Transforming Growth Factor beta1/genetics
19.
Artif Organs ; 31(11): 801-8, 2007 Nov.
Article in English | MEDLINE | ID: mdl-18001389

ABSTRACT

We tested the effects on the early-stage wound healing of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofiber matrices cultured with hair follicular cells. PHBV only, PHBV/collagen, and PHBV/gelatin at a 7/3 weight ratio were produced by electrospinning, and their in vitro cell culture and in vivo wound healing as biological dressings were examined. In cell attachment and growth on matrices, dermal sheath (DS) cells attached to hydrophilic PHBV/collagen and PHBV/gelatin faster than hydrophobic PHBV at the early incubation stage (up to 6 h). From 6- to 24-h incubation, PHBV/collagen showed the best results in cell culture. Furthermore, PHBV/collagen cocultured for 3-5 days with DS and epithelial outer root sheath (ORS) cells expressed more extracellular materials, such as type I collagen, elastin, and alpha-smooth muscle actin, than cocultured PHBV with the same cells. However, there was no significant difference between PHBV and PHBV/collagen in the amounts of cytokeratin 8 expressed. Grafting of PHBV and PHBV/collagen matrices cocultured with ORS/DS cells for 3-5 days showed that PHBV promoted wound closure and re-epithelization more obviously than PHBV/collagen in both cocultured matrices and matrices alone. Cocultured matrices would heal wounds better than the corresponding matrices alone. Thus, PHBV cocultured with ORS/DS cells could be used as a cell-seeded biological dressing, thereby reducing preparation time as well as regenerating the epidermis efficiently during the early stage of wound healing.


Subject(s)
Biological Dressings , Polyesters/pharmacology , Tissue Engineering/methods , Wound Healing/physiology , Wounds and Injuries/therapy , Animals , Cells, Cultured , Coculture Techniques , Dermis/cytology , Disease Models, Animal , Epithelial Cells/cytology , Hair Follicle/cytology , Humans , Mice , Mice, Nude , Random Allocation , Sensitivity and Specificity
20.
J Neurosurg Spine ; 7(2): 131-8, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17688051

ABSTRACT

OBJECT: The purpose of this prospective controlled study was to evaluate possible factors that could affect postoperative segmental range of motion (ROM) after lumbar total disc replacement (TDR) using the ProDisc II prosthesis. METHODS: Thirty-two consecutive patients with intractable discogenic pain underwent lumbar TDR using the ProDisc II prosthesis, 30 of whom were followed up for at least 24 months. Segmental ROM was assessed preoperatively and every 6 months postoperatively using dynamic x-ray films. Segmental ROM at the reference level was assessed in relation to patient age, sex, body mass index (BMI), levels with implants, preoperative ROM, prosthesis size, and prosthesis position. RESULTS: At the last follow-up visit, mean ROM of the disc prostheses was significantly increased from 4.23 +/- 3.12 degrees to 6.81 +/- 3.76 degrees at L3-4, and from 3.66 +/- 2.47 degrees to 6.09 +/- 2.11 degrees at L4-5. Mean ROM at L5-S1, however, was decreased from 3.12 +/- 1.56 degrees to 2.86 +/- 1.26 degrees (p > 0.05). This difference in the changes in postoperative ROM between L5-S1 and the other operated levels was the only statistically significant factor (p = 0.025) among the variables related to the postoperative ROM that the authors assessed, but other factors such as patient age, sex, BMI, disc height, and the size and position of the prosthesis were not related to segmental ROM. CONCLUSIONS: The data demonstrate that after TDR using the ProDisc II prosthesis, ROM of the prosthesis at L5-S1 is significantly lower compared with ROM at the other levels. In preserving ROM, the advantage of lumbar TDR using the ProDisc II might be minimal at L5-S1. Among the variables related to postoperative ROM, the level at which the ProDisc II prosthesis was implanted was the only one found to be statistically significant.


Subject(s)
Intervertebral Disc/physiopathology , Intervertebral Disc/surgery , Lumbar Vertebrae/physiopathology , Lumbar Vertebrae/surgery , Prostheses and Implants , Range of Motion, Articular , Adult , Female , Follow-Up Studies , Humans , Intervertebral Disc/diagnostic imaging , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Postoperative Period , Radiography , Sacrum/physiopathology , Time Factors
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