Type 1 Achilles tendon rupture caused by grooming trauma in a young dog

Achilles tendon rupture is uncommon in small animal practice. A 9-month-old, female, mixed breed dog (weighing 2.2kg) was referred to our hospital with a primary complaint of right hind limb lameness. Complete right Achilles tendon rupture was diagnosed by physical examination and radiography. The tendon was surgically repaired the next day by using a three-loop and single near-far-far-near suture methods. Complete healing was achieved by 97 days post-surgery. This report describes the surgical technique used for complete Achilles tendon rupture repair in a young dog.

Therapy-related myelodysplastic syndrome and acute myeloid leukemia following chemotherapy (paclitaxel and carboplatin) and radiation therapy in ovarian cancer: a case report

In recent years, the incidence of therapy-related myelodysplastic syndrome (t-MDS) and therapy-related acute myeloid leukemia (t-AML) that occur during chemotherapy for ovarian cancer has increased. While alkylating agents and topoisomerase II inhibitors are particularly mutagenic and have strong leukemogenic potential, paclitaxel and combination chemotherapy/radiation therapy also appear to induce t-MDS. The present authors report a case of t-MDS that developed during chemotherapy and radiation therapy for ovarian cancer. The patient was a 75-year-old woman who received six courses of cyclophosphamide/doxorubicin/cisplatin (CAP) therapy after initial surgery for Stage IIIc grade ovarian cancer in 1995. Beginning in February 2005, the patient experienced multiple recurrences due to sternal metastasis. Chemotherapy, including paclitaxel and carboplatin (TC), was administered intermittently and was combined with radiation therapy to a sternal metastatic lesion. Pancytopenia was observed in December 2008, and she was diagnosed with t-MDS (WHO subtype, refractory cytopenias with multilineage dysplasia [RCMD]): the time from first chemotherapy to t-MDS onset was 106 months. Without evidence of blast crisis, the recurrent lesions continued to grow and caused multiple cerebral infarctions, from which she eventually died. The cumulative doses of paclitaxel and carboplatin administered to this patient were 1,968 mg and 6,480 mg, respectively.

Exposure to cocaine regulates inhibitory synaptic transmission from the ventral tegmental area to the nucleus accumbens

Synaptic projections from the ventral tegmental area (VTA) to the nucleus accumbens (NAc) make up the backbone of the brain reward pathway, a neural circuit that mediates behavioural responses elicited by natural rewards as well as by cocaine and other drugs of abuse. In addition to the well-known modulatory dopaminergic projection, the VTA also provides fast excitatory and inhibitory synaptic input to the NAc, directly regulating NAc medium spiny neurons (MSNs). However, the cellular nature of VTA-to-NAc fast synaptic transmission and its roles in drug-induced adaptations are not well understood. Using viral-mediated in vivo expression of channelrhodopsin 2, the present study dissected fast excitatory and inhibitory synaptic transmission from the VTA to NAc MSNs in rats. Our results suggest that, following repeated exposure to cocaine (15 mg kg(-1) day(-1) × 5 days, i.p., 1 or 21 day withdrawal), a presynaptic enhancement of excitatory transmission and suppression of inhibitory transmission occurred at different withdrawal time points at VTA-to-NAc core synapses. In contrast, no postsynaptic alterations were detected at either type of synapse. These results suggest that changes in VTA-to-NAc fast excitatory and inhibitory synaptic transmissions may contribute to cocaine-induced alteration of the brain reward circuitry.

Distribution of amyloid burden differs between idiopathic normal pressure hydrocephalus and Alzheimer's disease

This study aimed to elucidate the incidence and distribution of the cortical retention of Pittsburgh compound B (PIB) in patients with idiopathic normal pressure hydrocephalus (iNPH) and clarify the differences from those in patients with Alzheimer's disease (AD). Ten patients with iNPH without any clinical signs indicative of AD were enrolled in this study. Cerebral retention of PIB in positron emission tomography (PET) in iNPH patients was compared with those in seven age-matched AD patients. The CSF levels of β-amyloid 1-42 peptide (Aβ42), which inversely decrease with cerebral amyloid burden, were also measured. Three of the ten patients with iNPH showed increased cortical PIB retention. Although the mean cortical SUV ratios were similar, the distribution of PIB retention differed widely between the patients with iNPH and AD. PIB retention was limited to the high-convexity parasagittal areas in iNPH patients, whereas it spread over the frontal and parietotemporal areas in AD. The coronal images of PIB-PET were more informative than conventional transverse images in evaluating the distribution pattern of cortical PIB retention. Two iNPH patients with higher cortical PIB retention had the lowest levels of CSF Aβ42, indicating that PIB retention in iNPH would not reflect a simple delay in PIB clearance but its binding to existing Aβ amyloid in the brain. Our results indicate that iNPH is one of the diseases exhibiting cortical PIB retention. The characteristic distribution of PIB retention in iNPH could be useful in the differential diagnosis between iNPH and AD.

Single-molecule imaging and spectroscopy using fluorescence and surface-enhanced Raman scattering

We extended single molecule fluorescence imaging and time-resolved fluorometry from the green to the violet-excitation regime to find feasibility of detecting and identifying fluorescent analogs of nucleic-acid bases at the single-molecule level. Using violet excitation, we observed fluorescent spotsfrom single complexes composed of a nucleotide analogue and the Klenow fragmentof DNA polymerase I. Also, we implemented Raman imaging and spectroscopy of adenine molecules adsorbed on Ag colloidal nanoparticles to find feasibility of identifying nucleic-acid bases at the single-molecule level. Surface enhanced Raman scattering (SERS) of adenine molecules showed an intermittent on-and-off behavior called blinking. The observation of blinking provides substantial evidence for detecting single adenine molecules.

Surgical treatment outcomes of serious chronic tubo-ovarian abscess: a single-center series of 20 cases

In recent years, Shimane University Hospital has begun to see patients with pelvic inflammatory disease (PID) which has become severe and chronic after insufficient conservative treatment in primary or secondary medical care facilities. Serious chronic tubo-ovarian abscess (TOA) is complicated by intraperitoneal inflammatory adhesions to surrounding organs, so that it is difficult to determine the original anatomical position of organs at surgery. Forcible synechotomy can result in damage to the adhering organs and insufficient drainage after surgery can cause recurrence of inflammation. In order to increase the chances for a successful surgical treatment, careful preparation, such as preoperative administration of antibiotics and ureteral stent insertion are necessary. In addition, the chances for recurrence of inflammation can be lessened by thorough intraperitoneal irrigation and insertion of a drainage tube.

Glutamatergic changes in the cerebral white matter associated with schizophrenic exacerbation

OBJECTIVE

Glutamatergic dysfunction in the brain has been implicated in the pathophysiology of schizophrenia. This study was aimed to examine several brain chemical mediators, including Glx (glutamate + glutamine), using (1)H magnetic resonance spectroscopy (MRS) in medicated patients with schizophrenia, with and without psychotic exacerbation.

METHOD

(1)H MRS was acquired in 24 patients with schizophrenia, with psychotic exacerbation; 22 patients without exacerbation; and 27 age- and sex-matched healthy volunteers. The levels of metabolites were measured in the left frontal and inferior parietal white matter and compared across the three groups.

RESULTS

The Glx level was significantly elevated in the left inferior parietal white matter in the patients with psychotic exacerbation in comparison with that in the healthy volunteers and the patients without exacerbation (P < 0.05). We also detected that there was a significant correlation between Positive and Negative Syndrome Scale-positive scale and Glx level in the left parietal white matter (r = 0.51, P < 0.001).

CONCLUSION

Higher than normal Glx levels indicate glutamatergic overactivity in the left inferior parietal white matter with schizophrenic exacerbation, a finding that is in accordance with the glutamatergic hypothesis in schizophrenia. The Glx level measured by (1)H MRS could be a biomarker for exacerbation in schizophrenia.

White matter alteration in idiopathic normal pressure hydrocephalus: tract-based spatial statistics study

BACKGROUND AND PURPOSE

White matter alteration in iNPH has not been well-investigated. TBSS is a voxelwise statistical analysis developed for DTI data. We aimed to elucidate the cerebral white matter alteration in patients with iNPH by using DTI and to test the accuracy of TBSS analysis.

MATERIALS AND METHODS

DTI data were obtained from 20 patients with iNPH and 20 age- and sex-matched controls. The FA values were evaluated by using TBSS, region-of-interest and tract-specific analysis of the CST. The accuracy of TBSS analysis was tested by using "back-projection" of TBSS results and by comparing the TBSS analysis results with those of region-of-interest and tract-specific analysis.

RESULTS

Back-projection of the TBSS results showed accurate registration of the whole brain, with the exception of parts of the thalamus, fornix, and white matter around the posterior body of the lateral ventricle. The TBSS analysis results were consistent with those of the region-of-interest analysis and tract-specific analysis. In patients with iNPH compared with control subjects, the FA values were significantly decreased in parts of the corpus callosum, periventricular white matter, and juxtacortical white matter in the frontal and parietal lobes. In contrast, FA values were significantly increased in the internal capsule, extending to the white matter in the centrum semiovale.

CONCLUSIONS

Our results suggest that patients with iNPH have various patterns of white matter damage and that TBSS analysis is a promising tool for performing accurate voxelwise statistical analysis of the iNPH brain, with the exception of misregistered areas.

Acute CO2-independent vasodilatation of penetrating and pre-capillary arterioles in mouse cerebral parenchyma upon hypoxia revealed by a thinned-skull window method

AIM

Investigating spatio-temporal relationship between regional metabolic changes and microvascular responses in hypoxic brain is critical for unravelling local O(2) -sensing mechanisms. However, no reliable method to examine the relationship has been available because of inherent disadvantages associated with use of a conventional cranial window preparation. We aimed to devise a method to solve the problem.

METHODS

Anaesthetized mice were equipped with either a conventional cranial window with craniotomy or a thinned-skull preparation. Mice were mechanically ventilated to avoid hypercapnia and exposed to systemic isobaric hypoxia for 30 min. Using two-photon laser scanning microscopy, nicotinamide adenine dinucleotide, reduced form (NADH) autofluorescence and diameter changes in penetrating and pre-capillary arterioles within the parenchyma were visualized to examine their temporal alterations.

RESULTS

With the conventional cranial window preparation, marked vertical displacement of the tissue occurred through oedema within 30 s after inducing hypoxia. With a thinned-skull preparation, however, such hypoxia-induced displacement was diminished, enabling us to examine acute spatio-temporal changes in diameters of penetrating and pre-capillary arterioles and NADH autofluorescence. Vasodilatation of these microvessels was evoked within 1 min after hypoxia, and sustained during the entire observation period despite the absence of hypercapnia. This event coincided with parenchymal NADH elevation, but the onset and peak dilatory responses of the penetrating arterioles preceded the local metabolic response of the parenchyma.

CONCLUSION

Observation of hypoxia-exposed brain by the thinned-skull preparation combined with two-photon intra-vital microscopy revealed rapid vasodilatory responses in penetrating arterioles preceding parenchymal NADH elevation, suggesting the presence of acute hypoxia-sensing mechanisms involving specific segments of cortical arterioles within the neurovascular unit.

DPP6 as a candidate gene for neuroleptic-induced tardive dyskinesia

We implemented a two-step approach to detect potential predictor gene variants for neuroleptic-induced tardive dyskinesia (TD) in schizophrenic subjects. First, we screened associations by using a genome-wide (Illumina HumanHapCNV370) SNP array in 61 Japanese schizophrenia patients with treatment-resistant TD and 61 Japanese schizophrenia patients without TD. Next, we performed a replication analysis in 36 treatment-resistant TD and 138 non-TD subjects. An association of an SNP in the DPP6 (dipeptidyl peptidase-like protein-6) gene, rs6977820, the most promising association identified by the screen, was significant in the replication sample (allelic P=0.008 in the replication sample, allelic P=4.6 × 10(-6), odds ratio 2.32 in the combined sample). The SNP is located in intron-1 of the DPP6 gene and the risk allele was associated with decreased DPP6 gene expression in the human postmortem prefrontal cortex. Chronic administration of haloperidol increased Dpp6 expression in mouse brains. DPP6 is an auxiliary subunit of Kv4 and regulates the properties of Kv4, which regulates the activity of dopaminergic neurons. The findings of this study indicate that an altered response of Kv4/DPP6 to long-term neuroleptic administration is involved in neuroleptic-induced TD.