Postoperative Computed Tomographic Assessment of the Complete Resection of an Infiltrative Lipoma Compressing the Spinal Cord in a Dog

Infiltrative lipomas, which are locally invasive tumors composed of well-differentiated adipocytes, are histologically identical to lipomas but have a tendency to infiltrate adjacent muscle and fibrous tissue without metastasis, such as muscle; connective tissue; bone; and, in rare cases, peripheral nerves and the spinal cord. They differ from liposarcomas yet also exhibit neoplastic cell infiltration and often recur despite surgical removal. A 10-year-old spayed Maltese female dog presented with hindlimb paresis and back pain for two months. Computed tomography and magnetic resonance imaging revealed an extensive fatty mass impinging on the vertebral canal, compressing the spinal cord, and extending into the surrounding muscle layers and thoracic cavity. The mass was surgically removed, and subsequent postoperative computed tomography confirmed complete removal of the mass using Vitrea® advanced visualization fat measurement. Histopathological analysis confirmed that the mass was an infiltrative lipoma. The patient's symptoms completely resolved after surgery, with no recurrence reported at the 2-year follow-up. This case highlights the benefits of using postoperative computed tomography combined with the automated fat measurement technique to determine whether reoperation is necessary or to predict patient prognosis by identifying potential residual lipoma post-surgery.

Surgical management of a metastatic vertebral tumour originating from a mammary adenocarcinoma in a dog

An 11-year-old spayed female Toy Poodle presented with acute tetraparesis. A small subcutaneous mass was found in the right trunk region, and the magnetic resonance revealed a compressive spinal cord lesion due to an irregular bone proliferation at the third cervical vertebra. After surgical resection of the vertebral lesion, the neurological symptoms improved, and the patient could walk on her own. The excised vertebral and subcutaneous masses were diagnosed as a mammary adenocarcinoma on the histopathological examination, with Ki-67 and HER-2 immunohistochemistry staining. This case report highlights the importance of defining the primary tumours of metastatic vertebral tumours and the necessity of palliative surgery to improve the patient's quality of life.

Platelet-rich plasma improves the therapeutic efficacy of mesenchymal stem cells by enhancing their secretion of angiogenic factors in a combined radiation and wound injury model

Delayed wound healing after radiation exposure can cause serious cutaneous damage, and its treatment is a major clinical challenge. Although mesenchymal stem cells (MSCs) have emerged as a promising therapeutic agent in regenerative medicine, they alone do not produce satisfactory effects in a combined radiation and wound injury (CRWI) model. Here, we investigated the therapeutic effect of combined umbilical cord blood-derived (UCB)-MSCs and platelet-rich plasma (PRP) treatment on wound healing in a CRWI mouse model. First, we assessed the release of cytokines from UCB-MSCs cultured with PRP and observed changes in the expression of angiogenic factors. The angiogenic paracrine factors from UCB-MSCs cultured with PRP were assessed in human umbilical vein endothelial cells (HUVECs). To assess therapeutic efficacy, UCB-MSCs and PRP were topically implanted into a CRWT mouse model. Vascular endothelial growth factor (VEGF), a pro-angiogenic growth factor, urokinase-type plasminogen activator and contributor to VEGF-induced signalling were more highly expressed in conditioned media of UCB-MSCs cultured with PRP than in that of UCB-MSCs alone. Furthermore, conditioned media of UCB-MSCs cultured with PRP increased the formation of tube-like structures in HUVECs. Co-treatment of UCB-MSCs and PRP in a CRWI mouse model increased the wound closure rate and angiogenesis compared with an untreated irradiated group. Moreover, increased expression of VEGF and CD31 were observed in the wound tissue of co-treated mice compared with untreated irradiated mice. PRP stimulates the release of angiogenic factors from UCB-MSCs, and combined therapy of UCB-MSCs and PRP improves regeneration efficacy by enhancing angiogenesis in a CRWI model.

Platelet-rich plasma activates AKT signaling to promote wound healing in a mouse model of radiation-induced skin injury

Background

The skin is impacted by every form of external radiation therapy. However, effective therapeutic options for severe, acute radiation-induced skin reactions are limited. Although platelet-rich plasma (PRP) is known to improve cutaneous wound healing, its effects in the context of high-dose irradiation are still poorly understood.

Methods

We investigated the regenerative functions of PRP by subjecting the dorsal skin of mice to local irradiation (40 Gy) and exposing HaCaT cells to gamma rays (5 Gy). The cutaneous benefits of PRP were gauged by wound size, histologic features, immunostains, western blot, and transepithelial water loss (TEWL). To assess the molecular effects of PRP on keratinocytes of healing radiation-induced wounds, we evaluated AKT signaling.

Results

Heightened expression of keratin 14 (K14) was documented in irradiated HaCaT cells and skin tissue, although the healing capacity of injured HaCaT cells declined. By applying PRP, this capacity was restored via augmented AKT signaling. In our mouse model, PRP use achieved the following: (1) healing of desquamated skin, acutely injured by radiation; (2) activated AKT signaling, improving migration and proliferation of K14 cells; (3) greater expression of involucrin in keratin 10 cells and sebaceous glands; and (4) reduced TEWL, strengthening the cutaneous barrier function.

Conclusions

Our findings indicate that PRP enhances the functions of K14 cells via AKT signaling, accelerating the regeneration of irradiated skin. These wound-healing benefits may have merit in a clinical setting.

Baicalein Mitigates Radiation-Induced Enteritis by Improving Endothelial Dysfunction

Background and Aims: Radiation-induced intestinal injury occurred in application of radiotherapy for abdominal and pelvic cancers or in nuclear accidents. Radiation-induced enteritis may be considered an ideal model of gastrointestinal inflammation. The endothelium is a crucial component of inflammation, and the endothelial dysfunction following radiation exposure induces the intestinal proinflammatory response and progression of radiation enteritis. Baicalein (5,6,7-trihydroxyflavonoid) is a flavonoid from Scutellaria baicalensis used in oriental herbal medicine. Baicalein has been found to have multiple beneficial properties including antioxidant, anti-inflammatory, anti-allergic, and anti-cancer activities. Here, we investigated the therapeutic effects of baicalein on endothelial dysfunction in radiation-induced intestinal inflammation. Materials and Methods: We performed histological analysis, bacterial translocation, and intestinal permeability assays and also assessed infiltration of leukocytes and inflammatory cytokine expression using a mouse model of radiation-induced enteritis. In addition, to investigate the effect of baicalein in endothelial dysfunction, we analyzed endothelial-derived adherent molecules in human umbilical vein endothelial cells (HUVECs) and irradiated intestinal tissue. Results: Histological damage such as shortening of villi length and impaired intestinal crypt function was observed in the radiation-induced enteritis mouse model. Intestinal damage was attenuated in baicalein-treated groups with improvement of intestinal barrier function. Baicalein inhibited the expression of radiation-induced adherent molecules in HUVECs and intestine of irradiated mouse and decreased leukocyte infiltration in the radiation-induced enteritis. Conclusions: Baicalein could accelerate crypt regeneration via recovery of endothelial damage. Therefore, baicalein has a therapeutic effect on radiation-induced intestinal inflammation by attenuating endothelial damage.

Photobiomodulation Enhances the Angiogenic Effect of Mesenchymal Stem Cells to Mitigate Radiation-Induced Enteropathy

Radiation-induced enteropathy remains a major complication after accidental or therapeutic exposure to ionizing radiation. Recent evidence suggests that intestinal microvascular damage significantly affects the development of radiation enteropathy. Mesenchymal stem cell (MSC) therapy is a promising tool to regenerate various tissues, including skin and intestine. Further, photobiomodulation (PBM), or low-level light therapy, can accelerate wound healing, especially by stimulating angiogenesis, and stem cells are particularly susceptible to PBM. Here, we explored the effect of PBM on the therapeutic potential of MSCs for the management of radiation enteropathy. In vitro, using human umbilical cord blood-derived MSCs, PBM increased proliferation and self-renewal. Intriguingly, the conditioned medium from MSCs treated with PBM attenuated irradiation-induced apoptosis and impaired tube formation in vascular endothelial cells, and these protective effects were associated with the upregulation of several angiogenic factors. In a mouse model of radiation-induced enteropathy, treatment with PBM-preconditioned MSCs alleviated mucosal destruction, improved crypt cell proliferation and epithelial barrier functions, and significantly attenuated the loss of microvascular endothelial cells in the irradiated intestinal mucosa. This treatment also significantly increased angiogenesis in the lamina propria. Together, we suggest that PBM enhances the angiogenic potential of MSCs, leading to improved therapeutic efficacy for the treatment of radiation-induced enteropathy.

Pravastatin Attenuates Acute Radiation-Induced Enteropathy and Improves Epithelial Cell Function

Background and Aim: Radiation-induced enteropathy is frequently observed after radiation therapy for abdominal and pelvic cancer or occurs secondary to accidental radiation exposure. The acute effects of irradiation on the intestine might be attributed to inhibition of mitosis in the crypts, as the loss of proliferative functions impairs development of the small intestinal epithelium and its barrier function. Especially, oxidative damage to intestinal epithelial cells is a key event in the initiation and progression of radiation-induced enteropathy. Pravastatin is widely used clinically to lower serum cholesterol levels and has been reported to have anti-inflammatory effects on endothelial cells. Here, we investigated the therapeutic effects of pravastatin on damaged epithelial cells after radiation-induced enteritis using in vitro and in vivo systems. Materials and Methods: To evaluate the effects of pravastatin on intestinal epithelial cells, we analyzed proliferation and senescence, oxidative damage, and inflammatory cytokine expression in an irradiated human intestinal epithelial cell line (InEpC). In addition, to investigate the therapeutic effects of pravastatin in mice, we performed histological analysis, bacterial translocation assays, and intestinal permeability assays, and also assessed inflammatory cytokine expression, using a radiation-induced enteropathy model. Results: Histological damage such as shortening of villi length and impaired intestinal crypt function was observed in whole abdominal-irradiated mice. However, damage was attenuated in pravastatin-treated animals, in which normalization of intestinal epithelial cell differentiation was also observed. Using in vitro and in vivo systems, we also showed that pravastatin improves the proliferative properties of intestinal epithelial cells and decreases radiation-induced oxidative damage to the intestine. In addition, pravastatin inhibited levels of epithelial-derived inflammatory cytokines including IL-6, IL-1β, and TNF-α in irradiated InEpC cells. We also determined that pravastatin could rescue intestinal barrier dysfunction via anti-inflammatory effects using the mouse model. Conclusion: Pravastatin has a therapeutic effect on intestinal lesions and attenuates radiation-induced epithelial damage by suppressing oxidative stress and the inflammatory response.

Rebamipide alleviates radiation-induced colitis through improvement of goblet cell differentiation in mice

BACKGROUND AND AIM

Radiation-induced colitis is a common clinical problem associated with radiotherapy and accidental exposure to ionizing radiation. Goblet cells play a pivotal role in the intestinal barrier against pathogenic bacteria. Rebamipide, an anti-gastric ulcer drug, has the effects to promote goblet cell proliferation. The aim of this study was to investigate whether radiation-induced colonic injury could be alleviated by rebamipide.

METHODS

This study orally administered rebamipide for 6 days to mice, which were subjected to 13 Gy abdominal irradiation, to evaluate the therapeutic effects of rebamipide against radiation-induced colitis. To confirm the effects of rebamipide on irradiated colonic epithelial cells, this study used the HT29 cell line.

RESULTS

Rebamipide clearly alleviated the acute radiation-induced colitis, as reflected by the histopathological data, and significantly increased the number of goblet cells. The drug also inhibited intestinal inflammation and protected from bacterial translocation during acute radiation-induced colitis. Furthermore, rebamipide significantly increased mucin 2 expression in both the irradiated mouse colon and human colonic epithelial cells. Additionally, rebamipide accelerated not only the recovery of defective tight junctions but also the differentiation of impaired goblet cells in an irradiated colonic epithelium, which indicates that rebamipide has beneficial effects on the colon.

CONCLUSIONS

Rebamipide is a therapeutic candidate for radiation-induced colitis, owing to its ability to inhibit inflammation and protect the colonic epithelial barrier.

Impaired Skin Barrier Due to Sebaceous Gland Atrophy in the Latent Stage of Radiation-Induced Skin Injury: Application of Non-Invasive Diagnostic Methods

Radiation-induced skin injury can take the form of serious cutaneous damage and have specific characteristics. Asymptomatic periods are classified as the latent stage. The skin barrier plays a critical role in the modulation of skin permeability and hydration and protects the body against a harsh external environment. However, an analysis on skin barrier dysfunction against radiation exposure in the latent stage has not been conducted. Thus, we investigated whether the skin barrier is impaired by irradiation in the latent stage and aimed to identify the molecules involved in skin barrier dysfunction. We analyzed skin barrier function and its components in SKH1 mice that received 20 and 40 Gy local irradiation. Increased transepidermal water loss and skin pH were observed in the latent stage of the irradiated skin. Skin barrier components, such as structural proteins and lipid synthesis enzymes in keratinocyte, increased in the irradiated group. Interestingly, we noted sebaceous gland atrophy and increased serine protease and inflammatory cytokines in the irradiated skin during the latent period. This finding indicates that the main factor of skin barrier dysfunction in the latent stage of radiation-induced skin injury is sebaceous gland deficiency, which could be an intervention target for skin barrier impairment.

Human umbilical cord blood-derived mesenchymal stromal cells and small intestinal submucosa hydrogel composite promotes combined radiation-wound healing of mice

BACKGROUND AIMS

Mesenchymal stromal cells (MSCs) are a promising agent for treating impaired wound healing, and their therapeutic potential may be enhanced by employing extracellular matrix scaffolds as cell culture scaffolds or transplant cell carriers. Here, we evaluated the effect of human umbilical cord blood-derived (hUCB)-MSCs and a porcine small intestinal submucosa (SIS)-derived extracellular matrix scaffold in a combined radiation-wound mouse model of impaired wound healing.

METHODS

hUCB-MSCs and SIS hydrogel composite was applied to the excisional wound of whole-body irradiated mice. Assessment of wound closing and histological evaluation were performed in vivo. We also cultured hUCB-MSCs on SIS gel and examined the angiogenic effect of conditioned medium on irradiated human umbilical vein endothelial cells (HUVECs) in vitro.

RESULTS

hUCB-MSCs and SIS hydrogel composite treatment enhanced wound healing and angiogenesis in the wound site of mice. Conditioned medium from hUCB-MSCs cultured on SIS hydrogel promoted the chemotaxis of irradiated HUVECs more than their proliferation. The secretion of angiogenic growth factors hepatocyte growth factor, vascular endothelial growth factor-A and angiopoietin-1 from hUCB-MSCs was significantly increased by SIS hydrogel, with HGF being the predominant angiogenic factor of irradiated HUVECs.

CONCLUSIONS

Our results suggest that the wound healing effect of hUCB-MSCs is enhanced by SIS hydrogel via a paracrine factor-mediated recruitment of vascular endothelial cells in a combined radiation-wound mouse model.

Processing of Soju Industrial Bioresidue to Extract Microcrystalline Cellulose and Characterization

Soju industrial biomass residue (SIBR) is a lignocellulosic agro-industrial biowaste available in large quantities in soju producing countries. In this study, an attempt was made to extract microcrystalline cellulose (MCC), a biopolymer from SIBR by controlled acid hydrolysis. X-ray diffraction analysis indicated the presence of cellulose I structure with two peaks around 2θ = 15 and 22.5° and increase in crystallinity after acid hydrolysis treatment. Fourier transform infrared analysis showed no significant chemical affect of the cellulose fragment. Thermo-gravimetric analysis reveals that the extracted MCC have a good thermal stability (319°C). Dynamic light scattering studies confirmed the presence of MCC in micro range (126.4 nm) which was supported by transmission electron microscopy. The results of this work are useful for extracting valuable and widely applicable cellulose, and help solve management of SIBR in terms of disposal and pollution problems.

Observation of inflammatory responses in mice orally fed with bacteriophage T7

AIMS

Analysis of inflammatory immune response upon bacteriophage intake in mice.

METHODS AND RESULTS

Bacteriophage therapy is emerging as an effective alternative to conventional antibiotics. However, its safety when applied to humans and animals remains a prime concern. This study investigated the inflammatory responses in mice fed orally with bacteriophages. The mice were fed with either murine norovirus (MNV) or bacteriophage T7 for 10 days and then sacrificed. No behavioural changes related to diet, movement or defecation were observed in either group. The inflammatory cytokine profiling showed an increased level of interleukins 1α (IL-1α), 1β (IL-1β), 2 (IL-2), 10 (IL-10), 12 (IL-12), 17A (IL-17A), interferon-γ (IFN-γ), tumour necrosis factor-α (TNF-α), granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) in the serum from the mice fed with MNV, whereas only a slight increase in IL-17A was observed in the serum from the mice fed with bacteriophage T7. A histopathological analysis of tissue samples from the stomach, small intestine and colon revealed no significant pathological change.

CONCLUSIONS

The bacteriophage diet only caused a minimal inflammatory response in the mice.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides insights into safety concerns of orally fed bacteriophage therapy.

Concomitant reconstruction of mandibular basal and alveolar bone with a free fibular flap

Repair of long-span mandibular defects with a free fibular flap is now a routine procedure. However, the bone height of the neo-mandible after reconstruction with a fibular flap is about half that of the dentulous mandible. When a fibular graft is placed only at the inferior border of the mandible, the resulting vertical discrepancy between the graft segment and the occlusal plane can adversely affect implant mechanics or denture stability and retention. To overcome these problems, we developed a technique for two-strut type mandibular reconstruction. A vascularized fibular segment is used to reconstruct the inferior basal portion of the neo-mandible, while a non-vascularized residual fibular segment is used to simulate the superior alveolar portion. We used this technique in 22 patients. Graft survival, graft resorption, and the ability to place implants were assessed as compared with those after the conventional one-strut type technique. The fibular segment grafted to the alveolar region was removed in one patient with intraoral wound dehiscence and in two with postoperative infection. All vascularized fibular flaps were successful. The resorption rate was 13.6+/-7.2% for non-vascularized segments and 3.0+/-3.7% for vascularized segments. Dental implants were placed in five of our 22 patients. The crown:fixture length ratio was improved to 1:1.7, as compared with a ratio of 1:1.21 with use of a conventional fibular flap. We conclude that our technique is very easy and safe and provides substantially improved lower-lip and cheek support and implant-prosthetic mechanics than conventional procedures for the repair of long-span mandibular defects.

A novel mechanism of virus-virus interactions: bacteriophage P2 Tin protein inhibits phage T4 DNA synthesis by poisoning the T4 single-stranded DNA binding protein, gp32

P2 prophages have been known to inhibit DNA replication and growth of T-even phages. We show here that this inhibition is due to poisoning of the T-even single-stranded DNA binding protein gp32 by the product of the nonessential P2 tin gene. Synthesis of Tin protein from a gene cloned in a multicopy plasmid is necessary and sufficient to completely prevent de novo DNA replication and growth of wild-type T2 or T4 phage. We isolated more than 20 independent mutants that render T-even phages resistant to poisoning by the P2 Tin protein. In all of these mutants, which we call asp, Asp codon 163 of gene 32 is changed to a Gly or Asn codon. The mutant alleles are recessive; i.e., when wild-type and asp mutants coinfect the same host cells, most DNA replication is poisoned by P2 Tin protein. To explain our results, we propose that the P2 Tin protein interacts with T-even gp32 at position 163 and distorts the helical filament of gene 32 protein on single-stranded DNA. Thereby Tin protein inhibits either assembly or function, or both, of the T4 replisome. The inhibition of late gene expression by P2 Tin protein may be an indirect consequence of inhibition of DNA replication.

Time-varying two-phase optimization and its application to neural-network learning

In this paper, a time-varying two-phase (TVTP) optimization neural network is proposed based on the two-phase neural network and the time-varying programming neural network. The proposed TVTP algorithm gives exact feasible solutions with a finite penalty parameter when the problem is a constrained time-varying optimization. It can be applied to system identification and control where it has some constraints on weights in the learning of the neural network. To demonstrate its effectiveness and applicability, the proposed algorithm is applied to the learning of a neo-fuzzy neuron model.

Hybrid evolutionary programming for heavily constrained problems

A hybrid of evolutionary programming (EP) and a deterministic optimization procedure is applied to a series of non-linear and quadratic optimization problems. The hybrid scheme is compared with other existing schemes such as EP alone, two-phase (TP) optimization, and EP with a non-stationary penalty function (NS-EP). The results indicate that the hybrid method can outperform the other methods when addressing heavily constrained optimization problems in terms of computational efficiency and solution accuracy.

The old exonuclease of bacteriophage P2

The Old protein of bacteriophage P2 is responsible for interference with the growth of phage lambda and for killing of recBC mutant Escherichia coli. We have purified Old fused to the maltose-binding protein to 95% purity and characterized its enzymatic properties. The Old protein fused to maltose-binding protein has exonuclease activity on double-stranded DNA as well as nuclease activity on single-stranded DNA and RNA. The direction of digestion of double-stranded DNA is from 5' to 3', and digestion initiates at either the 5'-phosphoryl or 5'-hydroxyl terminus. The nuclease is active on nicked circular DNA, degrades DNA in a processive manner, and releases 5'-phosphoryl mononucleotides.

Lipid selection in the assembly of the phospholipid bilayer membrane of the lipid-containing bacteriophage PR4

Phage PR4 contains a lipid bilayer within the phage protein capsid. The phospholipids of the bilayer are derived from those of the host. We report that phage morphogenesis selects against the unusually bulky phospholipids synthesized by Escherichia coli grown in the presence of various sugar alcohols. These data indicate that assembly of the PR4 lipid bilayer is a selective process rather than the bulk appropriation of host membrane lipids. We also demonstrates that phage PR4 morphogenesis is compatible with the incorporation of several abnormal lipids, monoacylglycerol, diacylglycerol, and phosphatidylinositol into the phage particle.

The major capsid protein of the lipid-containing bacteriophage PR4 is the precursor of two other capsid proteins

We report that capsid proteins P16 and P18 of bacteriophage PR4 are synthesized by post-translational processing of a portion of the major capsid protein, P2. A polyclonal antibody raised against purified P2 reacted with P16 and P18 as well as with P2. A monoclonal antibody reacted with both P2 and P18. The amino acid sequences of the N-termini of P2 and P18 exactly matched, indicating that P18 is derived from the N-terminal segment of P2. These data were confirmed by the analysis of the proteins encoded by various nonsense and missense P2 mutants. The 3129-bp MnlI-C fragment of the PR4 genome was shown to encode P2. The nucleotide sequence of this fragment was obtained and a single continuous ORF was found to encode P2, thus excluding introns and transcript processing in the production of P16 and P18. The DNA segment contained eight ORFs sized > 200 bp and the genes encoding proteins P6 and P6A as well as P2 were mapped by marker rescue analysis. We also report the isolation and characterization of a new class of P2 missense mutants.

The effect of hyperglycemia on lipid peroxidation in the global cerebral ischemia of the rat

To investigate the influence of hyperglycemia on ischemic brain damage, we measured brain ATP, lactate and malondialdehyde (MDA) levels in global cerebral ischemic models of Wistar rats. We induced global cerebral ischemia by the 4-vessel occlusion method. After 30 or 60 min of occlusion, and after 30 min of reperfusion, we measured brain ATP, lactate and MDA levels. During the ischemic period, brain ATP levels decreased to 30-70% of sham groups both in normoglycemic and hyperglycemic groups. But during the reperfusion period, the recovery rate of ATP levels was significantly lower in the hyperglycemic than in the normoglycemic groups (p less than 0.05). After 60 min of global ischemia, brain lactate increased much more in the hyperglycemic than in the normoglycemic group, and, during reperfusion, was washed out slowly in the hyperglycemic group. The MDA level, a parameter of lipid peroxidation, increased more in the hyperglycemic group than in the normoglycemic group during reperfusion periods (p less than 0.05). We conclude that hyperglycemia increases lactate accumulation, delays the recovery of energy metabolism, and enhances the lipid peroxidation in the transient global ischemia of rat brain. These findings may suggest the harmfulness of hyperglycemia in clinical cerebral ischemia.

Magnetic resonance imaging in brainstem ischemic stroke

To evaluate the efficacy of magnetic resonance imaging in brainstem stroke, we studied 21 cases of clinically definite brainstem ischemic stroke with brain magnetic resonance imaging (MRI) and conventional computed tomography (CT). MRI demonstrated brainstem lesions in 79% of the cases (16.5 out of 21), while CT revealed 33% (7 out of 21) when cases with suspicious lesions counted as 0.5. Although MRI was done a few days later than CT in most cases, MRI was superior to CT in detecting the number and the size of ischemic lesions, with clear delineation of anatomy and visualization of the status of the blood flow in the vertebral-basilar artery. Disappearance of the flow signal void in the basilar artery can be an important clue in diagnosing occlusion or thrombus of the basilar artery. By delineating the extent and the location of the infarction, MRI findings allowed an interpretation of whether the ischemic vessel is a small basilar branch or a large vessel vertebral or basilar artery.

MR demonstration of cryptic vascular malformation producing a palatal myoclonus--a case report

A 47-year-old man had suffered oscillopsia associated with palatal myoclonus for 10 years. High-field magnetic resonance imaging (MRI) revealed a cryptic vascular malformation within the "Guillain-Mollaret triangle" which was thought to be the responsible lesion.

Hypesthetic ataxic hemiparesis in a thalamic lacune

Right hemiparesis with an ipsilateral hypesthesia and ataxia developed in a 57-year-old man. Magnetic resonance imaging showed a left thalamic lacune bordering the medial portion of the posterior limb of the internal capsule. This finding implicated some pathogenetic mechanism of ataxic hemiparesis.

Cerebral sparganosis: CT characteristics

Cerebral sparganosis is an extremely rare parasitic zoonosis caused by a migrating plerocercoid tapeworm larva, genus Spirometra. Nineteen computed tomography (CT) scans of 12 patients with cerebral sparganosis were retrospectively analyzed and correlated with clinical and pathologic data. On CT scans, the following characteristics were noted: (a) unilateral involvement; (b) extensive or multifocal areas of low density along white matter bundles, with ipsilateral ventricular dilatation and localized cortical atrophy; (c) nodular or irregular enhancement with spotty calcification; and (d) change in location of enhancing nodules on sequential scans. These pathognomonic features reflect a chronic inflammatory process with both active granulomatous lesions and widespread degeneration of brain tissue, especially in the white matter. Degeneration is probably caused by migration of the long-surviving larva along the fiber tracts of white matter.