Probing surface noise with depth-calibrated spins in diamond

Sensitive nanoscale magnetic resonance imaging of target spins using nitrogen-vacancy (NV) centers in diamond requires a quantitative understanding of dominant noise at the surface. We probe this noise by applying dynamical decoupling to shallow NVs at calibrated depths. Results support a model of NV dephasing by a surface bath of electronic spins having a correlation rate of 200 kHz, much faster than that of the bulk N spin bath. Our method of combining nitrogen delta-doping growth and nanoscale depth imaging paves a way for studying spin noise present in diverse material surfaces.

Plasma matrix metalloproteinase-9 activity in cats with lymphoma

In this study, plasma MMP-9 activity was evaluated in cats with lymphoma. Plasma samples were obtained from 26 cats with lymphoma before treatment. From 13 of the included 26 cats, plasma samples were obtained 4 weeks after the initiation of treatment. Plasma samples were also obtained from 10 healthy cats as a control. Plasma MMP-9 activity was examined by gelatin zymography and semi-quantitative value (arbitrary unit; a.u.) for each sample was calculated. Relatively high levels of MMP-9 were observed in cats with lymphoma compared with those in healthy control cats. MMP-9 quantification through zymography showed significantly higher activity in cats with lymphoma (median, 0.63 a.u.; range, 0.23-3.24 a.u.) than in healthy controls (0.22 a.u.; 0.12-0.46 a.u.; P < 0.01). MMP-9 activities were significantly different before (0.73 a.u.; 0.30-3.24 a.u.) and after treatment (0.50 a.u.; 0.14-1.32 a.u.; P = 0.017). Measuring plasma MMP-9 activity in cats with lymphoma may become an appropriate monitoring tool for feline lymphoma.

Demonstration of the Cell Clonality in Canine Hematopoietic Tumors by X-chromosome Inactivation Pattern Analysis

X-chromosome inactivation pattern (XCIP) analysis has been widely used to assess cell clonality in various types of human neoplasms. In this study, a polymerase chain reaction–based canine XCIP analysis of the androgen receptor ( AR) gene was applied for the assessment of cell clonality in canine hematopoietic tumors. This XCIP analysis is based on the polymorphic CAG repeats in the AR gene and the difference of methylation status between active and inactive X chromosomes. We first examined the polymorphisms of 2 CAG tandem repeats in the AR gene in 52 male and 150 female dogs of various breeds. The 2 polymorphic CAG repeats contained 9 to 12 and 10 to 14 CAGs in the first and second CAG repeats, respectively. Of the 150 female dogs, 74 (49.3%) were heterozygous for the first and/or second polymorphic CAG tandem repeats, indicating the utility of XCIP analysis in these dogs. Canine XCIP analysis was then applied to clinical samples from female dogs with canine high-grade lymphoma, chronic myelogenous leukemia, acute myelogenous leukemia, and benign lymph node hyperplasia. Of 10 lymphoma cell samples, 9 (90%) showed skewed XCIPs, indicating their clonal origins, whereas all the nonneoplastic lymph node samples showed balanced XCIPs. Moreover, bone marrow specimen from a dog with acute myelogenous leukemia and peripheral leukocyte specimens from 2 dogs with chronic myelogenous leukemia showed skewed XCIPs. XCIP analysis was successfully employed to demonstrate the cell clonality of canine hematopoietic tumors in this study and will be applicable to evaluate the clonality in various proliferative disorders in dogs.

Use of the dye-guided sentinel lymph node biopsy method alone for breast cancer metastasis to avoid unnecessary axillary lymph node dissection

For sentinel lymph node biopsy (SLNB), a combination of dye-guided and γ-probe-guided methods is the most commonly used technique. However, the number of institutes in which the γ-probe-guided method is able to be performed is limited, since special equipment is required for the method. In this study, SLNB with the dye-guided method alone was evaluated, and the clinicopathological characteristics were analyzed to identify any factors that were predictive of whether the follow-up axillary lymph node dissection (ALND) was able to be omitted. A total of 374 patients who underwent SLNB between 1999 and 2009 were studied. The SLN identification rate was analyzed, in addition to the false-positive and false-negative rates and the correlation between the clinicopathological characteristics and axillary lymph node metastases. The SLN was identified in 96.8% of cases, and, out of the patients who had SLN metastasis, 63.0% did not exhibit metastasis elsewhere. The sensitivity was 96.4% and the specificity was 100%. The false-negative rate was 3.6%. Univariate analyses revealed significant differences in the lymph vessel invasion (ly) status, nuclear grade (NG), maximum tumor size and the percentage of the area occupied by the tumor cells in the SLN (SLN occupation ratio) between the patients with and without non-SLN metastasis, indicating that these factors may be predictive of axillary lymph node metastasis. Multivariate analysis revealed that ly status was an independent risk factor for non-SLN metastasis. In conclusion, SLN with the dye-guided method alone provided a high detection rate. The study identified a predictive factor for axillary lymph node metastasis that may improve the patients’ quality of life.

Computed tomographic morphology and clinical features of extrahepatic portosystemic shunts in 172 dogs in Japan

Canine extrahepatic congenital portosystemic shunts (EH-cPSS) are classified into several anatomical types, depending on the origin and termination of the shunt vessel. The aim of this retrospective study was to determine the proportion and clinical features of each anatomical shunt type in a population of dogs presented to a veterinary teaching hospital in Japan. Dogs diagnosed with EH-cPSS using computed tomographic (CT) portography were included (n=172) and shunts were classified based on previous reports. Clinical data were collected from case records and analysed statistically. The most common anatomical type was the spleno-phrenic shunt (n=64), followed by the spleno-azygos (n=38), right gastric-caval (n=29), spleno-caval (n=21), right gastric-caval with caudal loop (n=9), right gastric-phrenic (n=6), colono-caval (n=3), spleno-phrenic and azygos (n=1), and porto-caval (n=1) shunts. Spleno-phrenic and spleno-azygos shunts were diagnosed more frequently in older dogs than right gastric-caval and spleno-caval shunts (P<0.05). The portal vein/aortic (PV/Ao) ratio was significantly larger in dogs with spleno-phrenic shunts than in dogs with spleno-azygos, right gastric-caval or spleno-caval shunts (P<0.05). The PV/Ao ratio was significantly larger in dogs with spleno-azygos shunts than in dogs with right gastric-caval shunts. Dogs with spleno-phrenic shunts had significantly lower serum alkaline phosphatase activities than those with right gastric-caval or spleno-caval shunts. Dogs with spleno-phrenic shunts had significantly lower fasting ammonia concentrations than those with spleno-caval shunts.

The association between gall bladder mucoceles and hyperlipidaemia in dogs: a retrospective case control study

The diagnosis of gall bladder mucoceles (GM) in dogs has become increasingly frequent in veterinary medicine. Primary breed-specific hyperlipidaemia is reported in Shetland Sheepdogs and Miniature Schnauzers, breeds in which GM are known to occur more frequently than in other breeds. The objective of this study was to evaluate the association between GM and hyperlipidaemia in dogs. The study design was a retrospective case control study. Medical records of dogs diagnosed with GM at the Veterinary Medical Centre of The University of Tokyo between 1 April 2007 and 31 March 2012, were reviewed. Fifty-eight dogs with GM and a record of either serum cholesterol, triglyceride, or glucose concentrations were included in the study. Hypercholesterolaemia (15/37 cases; odds ratio [OR]: 2.92; 95% confidence interval [CI]: 1.02-8.36) and hypertriglyceridaemia (13/24 cases; OR: 3.55; 95% CI:1.12-15.91) showed significant association with GM. Pomeranians (OR: 10.69), American Cocker Spaniels (OR: 8.94), Shetland Sheepdogs (OR: 6.21), Miniature Schnauzers (OR: 5.23), and Chihuahuas (OR: 3.06) were significantly predisposed to GM. Thirty-nine out of 58 cases had at least one concurrent disease, including pancreatitis (five cases), hyperadrenocorticism (two cases), and hypothyroidism (two cases). A significant association between GM and hyperlipidaemia was confirmed, suggesting that hyperlipidaemia may play a role in the pathogenesis of GM.

American Cocker Spaniel chronic hepatitis in Japan

BACKGROUND

American Cocker Spaniels are predisposed to chronic hepatitis.

OBJECTIVE

To describe the clinical and histological features of chronic hepatitis in Japanese American Cocker Spaniels.

ANIMALS

Thirteen cases examined from 2003 to 2009.

METHODS

Retrospective study. Medical records were searched for American Cocker Spaniels with chronic liver diseases. History, physical examination, clinicopathologic features, hepatic ultrasonographic findings, hepatic histopathology, and immunohistochemistry were evaluated.

RESULTS

The median age was 4.6 (1.9-10.7) years. Clinical signs included inappetence (11/13), ascites (11/13), lethargy (9/13), diarrhea (7/13), and melena (2/13). Only 1/13 dogs was jaundiced. Clinicopathological abnormalities were increased liver enzymes (gamma-glutamyl transpeptidase: 9/12, aspartate aminotransferase: 7/10, alanine aminotransferase: 6/13, alkaline phosphatase: 6/13), increased total serum bile acid concentrations (10/12), and hypoalbuminemia (10/13). The liver had an irregular surface in all dogs and acquired portosystemic collaterals were verified in 11/13 dogs by abdominal ultrasound (2), laparoscopy (4), or both (5). Liver histology revealed severe fibrosis and cirrhosis in all cases, subdivided in lobular dissecting hepatitis (7), periportal fibrosis (1), micronodular cirrhosis (3), and macronocular cirrhosis (2). Inflammatory activity was low to mild. Immunohistochemical stains showed ductular proliferation. The median survival time was 913 (range: 63-1981) days.

CONCLUSION AND CLINICAL IMPORTANCE

Hepatitis in Japanese American Cocker Spaniels is clinically silent until an advanced stage and is associated with severe hepatic fibrosis leading to cirrhosis, extensive ductular/putative hepatic progenitor cell proliferation, portal hypertension, and acquired portosystemic collateral shunting, but relatively long survival times. Lobular dissecting hepatitis seems more prevalent than in previously reported cases from other countries.

Nanoscale nuclear magnetic resonance with a nitrogen-vacancy spin sensor

Extension of nuclear magnetic resonance (NMR) to nanoscale samples has been a longstanding challenge because of the insensitivity of conventional detection methods. We demonstrated the use of an individual, near-surface nitrogen-vacancy (NV) center in diamond as a sensor to detect proton NMR in an organic sample located external to the diamond. Using a combination of electron spin echoes and proton spin manipulation, we showed that the NV center senses the nanotesla field fluctuations from the protons, enabling both time-domain and spectroscopic NMR measurements on the nanometer scale.

Decreased immunoglobulin A concentrations in feces, duodenum, and peripheral blood mononuclear cells of dogs with inflammatory bowel disease

BACKGROUND

Although immunoglobulin A (IgA) plays a key role in regulating gut homeostasis, its role in canine inflammatory bowel disease (IBD) is unknown.

HYPOTHESIS

IgA expression may be altered in dogs with IBD, unlike that observed in healthy dogs and dogs with other gastrointestinal diseases.

ANIMALS

Thirty-seven dogs with IBD, 10 dogs with intestinal lymphoma, and 20 healthy dogs.

METHODS

Prospective study. IgA and IgG concentrations in serum, feces, and duodenal samples were measured by ELISA. IgA(+) cells in duodenal lamina propria and IgA(+) CD21(+) peripheral blood mononuclear cells (PBMCs) were examined by immunohistochemistry and flow cytometry, respectively. Duodenal expression of the IgA-inducing cytokine transforming growth factor β (TGF-β), B cell activating factor (BAFF), and a proliferation-inducing ligand (APRIL) was quantified by real-time RT-PCR.

RESULTS

Compared to healthy dogs, dogs with IBD had significantly decreased concentrations of IgA in fecal and duodenal samples. The number of IgA(+) CD21(+) PBMCs and IgA(+) cells in duodenal lamina propria was significantly lower in dogs with IBD than in healthy dogs or dogs with intestinal lymphoma. Duodenal BAFF and APRIL mRNA expression was significantly higher in IBD dogs than in the healthy controls. Duodenal TGF-β mRNA expression was significantly lower in dogs with IBD than in healthy dogs and dogs with intestinal lymphoma.

CONCLUSIONS AND CLINICAL IMPORTANCE

IBD dogs have decreased IgA concentrations in feces and duodenum and fewer IgA(+) PBMCs, which might contribute to development of chronic enteritis in dogs with IBD.

[A case of advanced primary colorectal carcinoma accompanied by liver metastasis in which ileus developed due to marked fibrosis with cicatricial formation in primary colorectal cancer treated by chemotherapy including bevacizumab]

A 64-year-old woman was introduced to our hospital with liver tumors. Our examination revealed that she had advanced colon carcinoma with multiple liver metastasis. Without symptoms from the primary cancer, she underwent chemotherapy of avastin FOLFOX. After 2 courses of chemotherapy, she suffered ileus and underwent operation. The resected specimen showed marked tumor necrosis and fibrosis, but few tumor cells remained in the primary lesion. We think this was a rare case of suffered ileus because of marked response of chemotherapy in primary colon carcinoma.

X-Chromosome Inactivation Pattern Analysis for the Assessment of Cell Clonality in Cats

X-chromosome inactivation pattern (XCIP) analysis has been widely used to assess cell clonality in various types of neoplasms in humans. In the present study, a polymerase chain reaction–based feline XCIP analysis using the feline androgen receptor gene was developed. To construct the system of the analysis, polymorphism in CAG tandem repeats within the feline androgen receptor gene was explored using somatic DNAs from 50 male and 103 female cats. CAG tandem repeats in exon 1 of the feline androgen receptor gene were found to be polymorphic, containing 15 to 22 CAG repeats. Of the 103 female cats, 70 (68%) were heterozygous for the number of CAG repeats, indicating the possible usefulness of XCIP analysis in cats. Application of the feline XCIP analysis to 3 feline mammary gland adenocarcinoma cell lines revealed distinctly skewed XCIPs in these cell lines, indicating their clonal origins. Twelve (80%) of the 15 primary tissue/cell samples obtained from cats with various neoplastic diseases showed skewed XCIPs. Moreover, bone marrow samples from 3 cats with myelodysplastic syndrome were also found to have skewed XCIPs. The polymerase chain reaction–based XCIP analysis developed in this study can provide information on cell clonality in female cats, potentially facilitating the differential diagnosis of various disorders in cats.

Optical analysis of developmental changes in synaptic potentiation in the neonatal rat corticostriatal projection

We applied voltage-sensitive dye imaging to neonatal rat cortical slice preparations and analyzed developmental changes in synaptic plasticity, long-term potentiation (LTP), in the corticostriatal projection. Coronal slice preparations were dissected from postnatal 1- to 21-day (P1-P21) rats, and the transmembrane voltage-related optical signals evoked by cortical stimulation were recorded using a 464ch optical recording system with the voltage-sensitive absorption dye. In the striatum, the optical signal was composed of a fast spike-like signal followed by a slow signal, which corresponded to an action potential and an excitatory postsynaptic potential (EPSP), respectively. The slow signal could be detected at the P1 stage, suggesting that the EPSP is already expressed in the corticostriatal projection at least at early stages after birth. On the other hand, the slow signal was potentiated with a single shot of tetanic stimulation and the potentiation lasted at least 1 h, which is considered to correspond to long-term potentiation. With ontogenetic examinations, we found that (1) the EPSP could be potentiated with tetanic stimulation from the P9 stage and that (2) after the LTP induction, the potentiation was maintained for a longer time in the postnatal 3W stage than in the 2W stage. These results suggest that characteristics of LTP change dynamically during postnatal development.

Anti-MuSK autoantibodies block binding of collagen Q to MuSK

OBJECTIVE

Muscle-specific receptor tyrosine kinase (MuSK) antibody-positive myasthenia gravis (MG) accounts for 5%-15% of autoimmune MG. MuSK mediates the agrin-signaling pathway and also anchors the collagenic tail subunit (ColQ) of acetylcholinesterase (AChE). The exact molecular target of MuSK-immunoglobulin G (IgG), however, remains elusive. As acetylcholine receptor (AChR) deficiency is typically mild and as cholinesterase inhibitors are generally ineffective, we asked if MuSK-IgG interferes with binding of ColQ to MuSK.

METHODS

We used 3 assays: in vitro overlay of the human ColQ-tailed AChE to muscle sections of Colq-/- mice; in vitro plate-binding assay to quantitate binding of MuSK to ColQ and to LRP4; and passive transfer of MuSK-IgG to mice.

RESULTS

The in vitro overlay assay revealed that MuSK-IgG blocks binding of ColQ to the neuromuscular junction. The in vitro plate-binding assay showed that MuSK-IgG exerts a dose-dependent block of MuSK binding to ColQ by but not to LRP4. Passive transfer of MuSK-IgG to mice reduced the size and density of ColQ to ∼10% of controls and had a lesser effect on the size and density of AChR and MuSK.

CONCLUSIONS

As lack of ColQ compromises agrin-mediated AChR clustering in Colq-/- mice, a similar mechanism may lead to AChR deficiency in MuSK-MG patients. Our experiments also predict partial AChE deficiency in MuSK-MG patients, but AChE is not reduced in biopsied NMJs. In humans, binding of ColQ to MuSK may be dispensable for clustering ColQ, but is required for facilitating AChR clustering. Further studies will be required to elucidate the basis of this paradox.

Effective education in radiation safety for nurses

In order to establish an efficient training program of radiation safety for nurses, studies have been carried out on the basis of questionnaires. Collaboration of nurses, who are usually standing closest to the patient, is necessary in order to offer safe radiological diagnostics/treatment. The authors distributed the questionnaire to 134 nurses in five polyclinic hospitals in Japan. Important questions were: fear of radiation exposure, knowledge on the radiation treatment, understanding the impact on pregnancy, and so on. Most of the nurses feel themselves uneasy against exposure to radiation. They do not have enough knowledge of radiological treatment. They do not know exactly what is the impact of the radiation on pregnant women. Such tendency is more pronounced, when nurses spend less time working in the radiological department. Nurses play important roles in radiological diagnostics/treatment. Therefore, a well-developed education system for radiation safety is essential. The training for the radiation safety in medicine should be done in the context of general safety in medicine. Education programs in undergraduate school and at the working place should be coordinated efficiently in order to ensure that both nurses and patients are informed about the meaning of radiation safety.