Intravascular Imaging-Guided Optimization of Complex Percutaneous Coronary Intervention by Sex: A Subgroup Analysis of the RENOVATE-COMPLEX-PCI Trial

Importance

There have been heterogeneous results related to sex differences in prognosis after percutaneous coronary artery intervention (PCI) for complex coronary artery lesions.

Objective

To evaluate potential differences in outcomes with intravascular imaging-guided PCI of complex coronary artery lesions between women and men.

Design, Setting, and Participants

This prespecified substudy evaluates the interaction of sex in the investigator-initiated, open-label, multicenter RENOVATE-COMPLEX-PCI randomized clinical trial, which demonstrated the superiority of intravascular imaging-guided PCI compared with angiography-guided PCI in patients with complex coronary artery lesions. The trial was conducted at 20 sites in Korea. Patients with complex coronary artery lesions undergoing PCI were enrolled between May 2018 and May 2021, and the median (IQR) follow-up period was 2.1 (1.4-3.0) years. Data were analyzed from December 2022 to December 2023.

Interventions

After diagnostic coronary angiography, eligible patients were randomly assigned in a 2:1 ratio to receive intravascular imaging-guided PCI or angiography-guided PCI. The choice and timing of the intravascular imaging device were left to the operators' discretion.

Main Outcomes and Measures

The primary end point was target vessel failure, defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. Secondary end points included individual components of the primary end point.

Results

Of 1639 included patients, 339 (20.7%) were women, and the mean (SD) age was 65.6 (10.2) years. There was no difference in the risk of the primary end point between women and men (9.4% vs 8.3%; adjusted hazard ratio [HR], 1.39; 95% CI, 0.89-2.18; P = .15). Intravascular imaging-guided PCI tended to have lower incidence of the primary end point than angiography-guided PCI in both women (5.2% vs 14.5%; adjusted HR, 0.34; 95% CI, 0.15-0.78; P = .01) and men (8.3% vs 11.7%; adjusted HR, 0.72; 95% CI, 0.49-1.05; P = .09) without significant interaction (P for interaction = .86).

Conclusions and Relevance

In patients undergoing complex PCI, compared with angiographic guidance, intravascular imaging guidance was associated with similar reduction in the risk of target vessel failure among women and men. The treatment benefit of intravascular imaging-guided PCI showed no significant interaction between treatment strategy and sex.

Trial Registration

ClinicalTrials.gov Identifier: NCT03381872.

The Relationship between Depression Severity and Prefrontal Hemodynamic Changes in Adolescents with Major Depression Disorder: A Functional Near-infrared Spectroscopy Study

Objective

: Numerous studies have identified hemodynamic changes in adults with major depressive disorder (MDD) by using functional near-infrared spectroscopy (fNIRS). However, studies on adolescents with MDD are limited. As adolescence is a stage of rapid brain development, differences may occur depending on age. This study used fNIRS as an objective tool to investigate hemodynamic changes in the frontal lobe according to depression severity and age in adolescents with MDD.

Methods

: Thirty adolescents (12 aged 12-15 years and 18 aged 16-18 years) were retrospectively investigated. The Children's Depression Inventory was used as a psychiatric evaluation scale, fNIRS was used as an objective brain function evaluation tool, and the Verbal Fluency Test was performed.

Results

: During the Verbal Fluency Test, in the younger MDD group, oxygenated-hemoglobin concentration increased in the right dorsolateral prefrontal cortex region as the severity of depression increased. In the older MDD group, the oxygenated-hemoglobin concentration decreased in the right dorsolateral prefrontal cortex region as the severity of depression increased.

Conclusion

: These results suggest that fNIRS may be an objective tool for identifying age differences among adolescents with MDD. To generalize the results and verify fNIRS as a potential biomarker tool, follow-up studies with a larger sample group should be conducted.

Effect of the sexual abstinence period recommended by the World Health Organization on clinical outcomes of fresh embryo transfer cycles with normal ovarian response after intracytoplasmic sperm injection

This study was to investigate whether the sexual abstinence period (SAP) recommended by the World Health Organization (WHO) affects clinical outcomes. We compared the rate of clinical outcomes between 2-7 and ≥8 days of SAP in first fresh embryo transfer after intracytoplasmic sperm injection (ICSI) in groups of young maternal age (YMA: <38 years) and old maternal age (OMA: ≥38 years). We conducted a retrospective study of 449 first ICSI cycles with a normal ovarian response. SAP was identified before collecting the semen samples. Semen analysis was performed based on the guidelines recommended by WHO (2010). Sperm preparation was made using the swim-up method. Patients' baseline characteristics in the YMA and OMA groups did not differ. The rates of fertilisation, top-quality embryos on day 3, biochemical pregnancy, clinical pregnancy, ongoing pregnancy, abortion and implantation per cycle were not significantly different between 2-7 and ≥8 days of SAP in the YMA or OMA group. In conclusion, SAP beyond the recommended period by WHO was not associated with the rates of a lower fertilisation and pregnancy in human in vitro fertilisation (IVF). We think that a new criterion of SAP for clinical application in human IVF needs to be considered by WHO.

Prediction of pathological complete response of breast cancer patients undergoing neoadjuvant chemotherapy: usefulness of breast MRI computer-aided detection

OBJECTIVE

To evaluate the usefulness of MR computer-aided detection (CAD) in patients undergoing neoadjuvant chemotherapy for prediction of the pathological complete response of tumours.

METHODS

148 patients with breast cancer (mean age, 47.3 years; range, 29-72 years) who underwent neoadjuvant chemotherapy were included in our study. They underwent MRI before and after neoadjuvant chemotherapy, and we reviewed the pathological result as the gold standard. The computer-generated kinetic features for each lesion were recorded, and the features analysed included "threshold enhancement" at 50% and 100% minimum thresholds; degree of initial peak enhancement; and enhancement profiles comprising lesion percentages of washout, plateau and persistent enhancement. The final pathological size and character of tumours were correlated with post-chemotherapy mammography, ultrasonography and MR CAD findings. Kruskal-Wallis test and intraclass correlation coefficient were used to analyse the findings.

RESULTS

We divided the 148 patients into complete pathological response and non-complete pathological response groups. A complete pathological response was defined as no histopathological evidence of any residual invasive cancer cells in the breast or axillary lymph nodes. 39 patients showed complete pathological response, and 109 patients showed non-complete pathological response. Between enhancement profiles of MR CAD, plateau proportion of tumours was significantly correlated with the pathological response of tumours (mean proportion of plateau on complete pathological response group was 27%, p = 0.007).

CONCLUSION

When plateau proportion of tumours is high, we can predict non-complete pathological response of neoadjuvant chemotherapy.

ADVANCES IN KNOWLEDGE

MR CAD can be a useful tool for the assessment of response to neoadjuvant chemotherapy and prediction of pathological results.

Assessment of extent of breast cancer: comparison between digital breast tomosynthesis and full-field digital mammography

AIM

To compare the accuracy of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) in preoperative assessment of local extent of breast cancer.

MATERIALS AND METHODS

Lesion sizes of breast cancers on DBT and FFDM images were independently evaluated by breast radiologists. Each lesion was flagged as either mis-sized or not depending on whether the assessment of size at imaging was within 1 cm of the lesion size at surgery. Additional analyses were made by mammographic parenchymal density and by lesion size, using 2 cm as the boundary to separate the two subgroups. Statistical comparisons were performed using a repeated measures linear model on the percent mis-sized. P-values < 0.05 were considered statistically significant.

RESULTS

The dataset included 173 malignant breast lesions (mean size 23.8 mm, 43% of lesions were ≤2 cm in size) in 169 patients, two-thirds of which had heterogeneously or extremely dense breasts. Overall, the percentage of lesions mis-sized at DBT was significantly lower than at FFDM (19% versus 29%, p = 0.003). There was significantly less mis-sizing at DBT in both heterogeneously dense breasts (11.1% difference between DBT and FFDM, p = 0.016) and extremely dense breasts (15.8% difference, p = 0.024). DBT also had significantly less mis-sizing than FFDM in the subgroup of lesions that were ≤2 cm in size (14.7% difference, p = 0.005).

CONCLUSION

DBT was significantly superior to FFDM for the evaluation of lesion size overall, and specifically for small lesions and for lesions in dense breasts. The superiority of DBT versus FFDM increased with parenchymal density.

Longitudinal split of the posterior cruciate ligament: description of a new MR finding and evaluation of its potential clinical significance

AIM

To evaluate the clinical significance of the intra-substance longitudinal split of the posterior cruciate ligament (LS-PCL) and to evaluate its potential clinical significance on MRI.

MATERIALS AND METHODS

The databases of two centres were searched for LS-PCL, 6917 knee magnetic resonance imaging (MRI) examinations undertaken were retrospectively reviewed. LS-PCL was defined as increased signal intensity in a PCL in the longitudinal direction, but with an intact ligament outer surface on MRI. Twelve patients were enrolled in this study. Available arthroscopic results, degree of posterior knee instability, and changes in MRI findings, or the degree of instability during follow-up (FU), were reviewed from the patients medical records and via their MRI images. MRI images were reviewed by two musculoskeletal radiologists in consensus for presence and location of LS-PCL and any combined injuries: menisci lesions, ligament injuries, and bone marrow changes.

RESULTS

Seven of 12 patients (58.3%) had morphological or functional evidence of PCL injury or insufficiency according to the change of posterior instability on FU stress testing (n=3), insufficiency during arthroscopy (n=2), or decreased extent and altered shape of the PCL split on the FU MRI (n=3). One patient revealed both change of posterior instability on FU stress testing and insufficiency during arthroscopy. Combined injuries were revealed in seven patients. Five patients had isolated LS-PCL: two patients underwent arthroscopic PCL reconstructions; and another three patients revealed knee instability on stress testing.

CONCLUSION

Although LS-PCL has not been described before, it can be a type of partial tear of the PCL, which causes PCL insufficiency.

Identification of process operating state with operational map in municipal wastewater treatment plant

This work was performed to develop an operational map for the objective diagnosis of the process operating states of a municipal wastewater treatment plant, for which multivariate statistical analysis techniques were applied. PCA (principal component analysis) was used to reduce the dimension of the data sets obtained from the field municipal wastewater treatment plant. A K-means clustering analysis was used to classify the group according to the property of the process operating state. A Fisher's linear discriminant analysis was used to derive the discriminant function of each classified group. An operational map was developed by scatter-plotting the derived principal components (PCs) on a two-dimensional coordinate according to the classified groups. Using the new data sets not used for developing the operational map, the practical usefulness of the operational map and discriminant function in diagnosing the process operating state were evaluated. Hence, the process operating state could be easily and quickly diagnosed and the dynamic trend of the process operating state was also able to be estimated using the operational map.

Vertebroplasty: magnetic resonance findings related to cement leakage risk

PURPOSE

To find magnetic resonance (MR) findings predicting cement leakage in patients receiving percutaneous vertebroplasty (PVP) due to osteoporotic compression fractures.

MATERIAL AND METHODS

MR was done in 43 patients (age 52-89 years) before PVP (56 vertebrae), which was done via a bipedicular approach with fluoroscopic monitoring. Shortly after the procedure, a non-contrast-enhanced computed tomography (CT) scan was done at the vertebroplasty sites for evaluation of bone cement leakage. The following MR findings of fractured vertebral bodies were retrospectively reviewed for correlation with leakage risk: severity of bone-marrow edema, presence of a T2-weighted low-signal-intensity line, percentage residual vertebral body height, presence of either a vacuum or cystic change within the vertebral body, and presence of a cortical disruption.

RESULTS

After PVP, cement leakage was detected in 35 vertebrae (62.5%). Leakage was most frequently observed in the anterior external vertebral venous plexus (46%). Cement leakage rate increased when there was a cortical disruption (P = 0.037), especially at the endplates, while it decreased when there was a vacuum or a cystic change within the fractured vertebra (P = 0.019). Other MR findings were not related to the risk of cement leakage.

CONCLUSION

The risk of cement leakage in PVP increases when MR shows cortical disruption in a fractured vertebral body, especially at the endplates. It decreases when MR shows a vacuum or cystic change within the body.

High frequency broadband PZT thick film ultrasonic transducers for medical imaging applications

A modified sol-gel method is used to prepare PZT thick film on Pt-coated silicon substrate. A new method of vacuum filling sol-gel precursor solution is introduced to improve film quality. The effects of the filling on PZT thick film structure and ferroelectric properties are discussed. The fabrication of a high frequency transducer with the PZT film as the actuating layer is described. The performance of the transducer is measured and results show that the transducer backed by E-Solder without a matching layer has a center frequency of 103 MHz and a bandwidth of 70%. Beam profile measurements show that the transducer has an axial resolution of 9.2 microm and a lateral resolution of 33 microm.

Synthesis and In vitro binding affinities of 1-azabicyclic compounds as muscarinic ligands

Two series of compounds, 2 and 3, were synthesized and their binding affinities were evaluated for the human recombinant muscarinic M(1) receptor subtype expressed in CHO cells. Comparing their binding affinities for the NMS binding sites and the Oxo-M binding sites, they were assumed as agonists. In particular, compound 2e was a good ligand for the agonist binding sites with an IC(50) of 23 nM, which represents over 1585 times stronger binding than for the antagonist binding sites.

Expression of osteopontin mRNA in developing rat brainstem and cerebellum

This study was undertaken to investigate the developmental expression of osteopontin (OPN) in the rat brainstem and cerebellum by Northern blotting and in situ hybridization. The expression of OPN was noted in the mesencephalic Vth nucleus initially at embryonic day 16 (E16). At E20, the labeling extended into other brainstem nuclei including the cochlear, vestibular, facial motor, and hypoglossal nuclei. During the first week of postnatal life, the OPN signal in the brainstem increased markedly, and by P14, OPN expression was found in functionally diverse areas including motor-related areas, sensory relay nuclei, and the reticular formation. The adult labeling pattern was established in central neurons at this time. These results corresponded well with those from Northern blot analysis. On the basis of morphological and distribution criteria, the OPN signal in several nuclei appeared to be contained exclusively within neuronal soma. OPN expression in neurons occurred during the period of neuronal differentiation and increased with maturation. Our results therefore suggest that OPN contributes to developmental processes, including the differentiation and maturation of specific neuronal populations, in the rat brain.

Treatment of vitiligo with suction epidermal grafting by the use of an ultrapulse CO2 laser with a computerized pattern generator

BACKGROUND

Laser ablation is used to remove the recipient epidermis in the suction epidermal grafting in vitiligo surgery.

OBJECTIVE

To evaluate the effectiveness and safety of a suction epidermal grafting method after the removal of the epidermis by the use of the Ultrapulse CO2 laser with a computerized pattern generator.

METHODS

Eleven patients with 34 lesions of refractory stable vitiligo were studied.

RESULTS

Of the 34 lesion sites, excellent repigmentation was seen in 30 and the other 4 had good repigmentation. No complications occurred.

CONCLUSION

The Ultrapulse CO2 laser is particularly well suited for deepithelialization in vitiligo surgery.

Remotivation therapy and Huntington's disease

Huntington's disease (HD) is a genetic, autosomal dominant, neurodegenerative disorder for which there is no known cure. Because remotivation therapy (RmT) has been effective in other neurological conditions and because of the lack of current efficacious treatments for HD, RmT may be a beneficial therapy for persons suffering from the disease. By cultivating a more fertile environment, RmT leads to increased self-awareness, self-esteem, and an improved quality of life, even in late-stage HD. Two recent studies using animal models suggest that exposure of transgenic HD mice to a stimulating, enriched environment helped to prevent the loss of cerebral volume and delay the onset of motor disorders. Six case studies are presented that demonstrate improved physical, mental, and social functioning in persons with HD when a more stimulating environment is provided.

Six cases of confluent and reticulated papillomatosis alleviated by various antibiotics

Confluent and reticulated papillomatosis (CRP) is a relatively rare disorder manifested by persistent papules that are confluent in the center and reticulated at the periphery with a characteristic distribution. Recently, many cases of CRP treated with minocycline have been reported, and their effect seems to be derived from their antibiotic properties. We report 6 cases of CRP alleviated by various antibiotics. The patient described in case 1 is a 16-year-old girl whose disease was alleviated by oral minocycline, 100 mg daily for 8 weeks. Cases 2 and 3 describe an 18-year-old woman and a 17-year-old male adolescent whose disease was reduced by oral fusidic acid, 1000 mg daily for 4 weeks. Case 4 describes a 14-year-old girl who received oral clarithromycin, 500 mg daily for 5 weeks. Case 5 describes a 22-year-old woman whose disease was reduced by oral erythromycin, 1000 mg daily for 6 weeks. Case 5 reports a 24-year-old man who received oral azithromycin, 500 mg daily 3 times per week for 3 weeks. Complete clearing after treatment with antibiotics raises the possibility that CRP is triggered by a bacterial infection and that antibiotics are the treatment of choice for CRP.

A randomized, controlled trial of remacemide for motor fluctuations in Parkinson's disease

BACKGROUND

Preclinical studies suggest that glutamate antagonists help ameliorate motor fluctuations in patients with PD treated with levodopa.

METHODS

In a multicenter, randomized, double-blind, placebo-controlled, parallel-group, dose-ranging study, the authors assessed the safety, tolerability, and efficacy of the glutamate receptor blocker remacemide hydrochloride in 279 patients with motor fluctuations treated with levodopa. The primary objective was to assess the short-term tolerability and safety of four dosage levels of remacemide during 7 weeks of treatment. Patients were also monitored with home diaries and the Unified PD Rating Scale (UPDRS) to collect preliminary data on treatment efficacy.

RESULTS

Remacemide was well tolerated up to a dosage of 300 mg/d on a twice daily schedule and 600 mg/d on a four times daily schedule. The most common dosage-related adverse events were dizziness and nausea, as observed in previous studies of remacemide. The percent "on" time and motor UPDRS scores showed trends toward improvement in the patients treated with 150 and 300 mg/d remacemide compared with placebo-treated patients, although these improvements were not significant.

CONCLUSION

Remacemide is a safe and tolerable adjunct to dopaminergic therapy for patients with PD and motor fluctuations. Although this study had limited power to detect therapeutic effects, the observed improvement is consistent with studies of non-human primates with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian signs and symptoms. Additional studies are warranted to confirm these results over an extended period of observation, and to explore the potential neuroprotective effects of remacemide in slowing the progression of PD.

Glutamate receptor dysregulation in the hippocampus of transgenic mice carrying mutated human amyloid precursor protein

Alzheimer's disease transgenic mice overexpressing human amyloid precursor protein (hAPP) with the Swedish double mutation (hAPP(Sw)) develop age-related amyloid deposition and behavioral and electrophysiologic changes by an unknown mechanism. Analysis of glutamatergic receptor subtypes in 4- and 15-month-old heterozygous hAPP(Sw) transgenic mice revealed a selective increase in AMPA receptor binding in the hippocampus of 15-month-old transgenic mice, which have established cortical and hippocampal amyloid deposits. There were no significant alterations of GluR1, GluR2, and GluR4 protein expression by semiquantitative confocal analysis or GluR1 mRNA by in situ hybridization. There was no significant alteration in NMDA, in group I and II metabotropic glutamate and in muscarinic receptor binding, or in striatal dopamine and adenosine receptor binding in 15-month-old mice. These data suggest that mutant APP overexpression or age-related amyloid deposition produce a subtle specific alteration in hippocampal glutamate receptors with aging.

Ultrasonographic evaluation of the gallbladder: comparison of fundamental, tissue harmonic, and pulse inversion harmonic imaging

The purpose of our study was to compare pulse inversion harmonic imaging, tissue harmonic imaging, and fundamental imaging in the evaluation of normal and diseased gallbladder. Gallbladders in 170 patients were examined with fundamental imaging, tissue harmonic imaging, and pulse inversion harmonic imaging using a 2- to 5-MHz curved array transducer. Images were divided into normal and abnormal groups. The sharpness of the wall and degree of internal artifact were evaluated in normal groups, and lesion conspicuity and internal artifact were evaluated in abnormal groups. In images of both normal and abnormal gallbladder, significant differences were demonstrated among the 3 imaging methods (P < .001), and pulse inversion harmonic imaging provided the best image quality and the least artifact. Tissue harmonic imaging was the next best, providing better image quality and less artifact than fundamental imaging. In conclusion, pulse inversion harmonic imaging provided the best image quality and the least artifact among the 3 ultrasonographic methods in the evaluation of both normal and abnormal gallbladder.

Up-regulated CNTF plays a protective role for retrograde degeneration in the axotomized rat retina

Using reverse transcription-polymerase chain reaction and in situ hybridization, we investigated the expression and cellular localization of ciliary neurotrophic factor receptor alpha (CNTFRalpha) in the rat retina following optic nerve transection (ONT). Following ONT, a signal for CNTFRalpha mRNA appeared in a layer-specific and time-dependent manner. In the ganglion cell layer, the signal showed a peak value 1 day after ONT, and then gradually decreased. In the inner nuclear layer the signal reached a peak value at 14 days of about 500% of control level, but then decreased at 4 weeks. Our findings suggest that CNTF might play a protective role for the retrograde degeneration of retinal cells induced by ganglion cell death in the rat retina following ONT.

A case of classic Kaposi's sarcoma with multiple organ involvement

Kaposi's sarcoma is a systemic, multifocal, angiomatous tumor which can be classified into four clinical variants. Among them, classic Kaposi's sarcoma is rare in Oriental people, and the involvement of internal organs in this variant is reported to be very rare. We present a case of classic Kaposi's sarcoma in a 67-year-old Korean male, who had multiple organ involvement in the skin, lymph node, and stomach. Lesions of Kaposi's sarcoma cleared after treatment with etoposide, but the skin lesions recurred after a three-month symptom-free period. He was treated with doxorubicin, bleomycin, and vincristine, and all the skin lesions were cleared.

Transcriptional dysregulation in Huntington's disease

Although the gene responsible for Huntington's disease was discovered in 1993, the pathogenic mechanisms by which mutant huntingtin causes neuronal dysfunction and death remain unclear. However, increasing evidence suggests that mutant huntingtin disrupts the normal transcriptional program of susceptible neurons. Thus, transcriptional dysregulation might be an important pathogenic mechanism in Huntington's disease.

Preoperative evaluation of Klatskin tumor: accuracy of spiral CT in determining vascular invasion as a sign of unresectability

BACKGROUND

To assess the accuracy of spiral computed tomography (CT) in predicting the resectability of Klatskin tumor as determined by vascular invasion.

METHODS

Twenty-one consecutive patients with Klatskin tumor who had undergone laparotomy were included in this study. The preoperative thin-section (5-mm-thick) spiral CT scans of these patients were assessed for the surgical resectability of tumor by evaluating the vascular invasion. The criterion for vascular invasion indicating unresectability was the tumoral invasion of the proper hepatic artery or main portal vein or simultaneous invasion of one side of the hepatic artery and the other side of the portal vein.

RESULTS

All nine patients with tumors thought to be unresectable on the basis of CT findings had tumors that were unresectable at surgery (positive predictive value, 100%). Of 12 patients with tumors thought to be resectable, six had resectable tumors (negative predictive value, 50%). Spiral CT failed to detect small hepatic metastasis (n = 1), lymph node metastasis (n = 1), extensive tumor (n = 2) and variation of bile duct (n = 2), which precluded surgical resection.

CONCLUSION

Spiral CT is a reliable method for detecting vascular invasion and unresectable tumors. However, it has limitations in detecting variations of the bile duct or the intraductal extent of tumor.

Molecular characterization of key diphtheria toxin:receptor interactions

The major amino acids necessary for diphtheria toxin (DT) binding to its receptor have been identified previously. Studies by W. H. Shen et al. (J. Biol. Chem. 269, 29077-29084, 1994) and by J. H. Cha et al. (Mol. Microbiol. 29 (5), 1275-1284, 1998) suggested that the positively charged nature of the single amino acid residue, (516)Lys of DT, is crucial for binding to the DT receptor, whereas the negatively charged (141)Glu of the DT receptor is the most important residue for toxin binding. Here, we hypothesize that key interactions occur between these two oppositely charged amino acid residues. Reciprocal substitution of the residues at these positions between the toxin and the receptor was performed, which resulted in a partial reconstitution of the toxin:receptor interaction. This study provides the first biological data that characterizes the specific interaction of these two key residues with each other and also the additional interactions between other positively charged residues of DT and (141)Glu of the DT receptor.

Minocycline inhibits caspase-1 and caspase-3 expression and delays mortality in a transgenic mouse model of Huntington disease

Huntington disease is an autosomal dominant neurodegenerative disease with no effective treatment. Minocycline is a tetracycline derivative with proven safety. After ischemia, minocycline inhibits caspase-1 and inducible nitric oxide synthetase upregulation, and reduces infarction. As caspase-1 and nitric oxide seem to play a role in Huntington disease, we evaluated the therapeutic efficacy of minocycline in the R6/2 mouse model of Huntington disease. We report that minocycline delays disease progression, inhibits caspase-1 and caspase-3 mRNA upregulation, and decreases inducible nitric oxide synthetase activity. In addition, effective pharmacotherapy in R6/2 mice requires caspase-1 and caspase-3 inhibition. This is the first demonstration of caspase-1 and caspase-3 transcriptional regulation in a Huntington disease model.

Decreased expression of striatal signaling genes in a mouse model of Huntington's disease

To understand gene expression changes mediated by a polyglutamine repeat expansion in the human huntingtin protein, we used oligonucleotide DNA arrays to profile approximately 6000 striatal mRNAs in the R6/2 mouse, a transgenic Huntington's disease (HD) model. We found diminished levels of mRNAs encoding components of the neurotransmitter, calcium and retinoid signaling pathways at both early and late symptomatic time points (6 and 12 weeks of age). We observed similar changes in gene expression in another HD mouse model (N171-82Q). These results demonstrate that mutant huntingtin directly or indirectly reduces the expression of a distinct set of genes involved in signaling pathways known to be critical to striatal neuron function.

Cell surface monkey CD9 antigen is a coreceptor that increases diphtheria toxin sensitivity and diphtheria toxin receptor affinity

Monkey (Mk) CD9 antigen has been shown previously to increase the diphtheria toxin (DT) sensitivity of cells when co-expressed with Mk proHB-EGF (DT receptor). We have elucidated here the mechanism whereby Mk CD9 influences Mk proHB-EGF and present evidence that Mk CD9 is a coreceptor for DT. We observed that Mk CD9 not only increased the DT sensitivity but also increased the DT receptor affinity of cells. Furthermore, the higher the Mk CD9/Mk proHB-EGF ratio, the higher the affinity. In contrast, mouse (Ms) CD9 did not increase the toxin sensitivity or receptor affinity of cells when co-expressed with Mk proHB-EGF. Using Mk/Ms chimeric CD9 molecules, we determined that the second extracellular domain of Mk CD9 is responsible for both increased sensitivity and receptor affinity. This domain of Mk CD9 also interacts with Mk proHB-EGF in a yeast two-hybrid system. Our findings thus suggest that Mk CD9 has a direct physical interaction with Mk proHB-EGF to form a DT receptor complex and that this contact may change the conformation of the receptor to increase DT binding affinity and consequently increase toxin sensitivity. We thus propose that Mk CD9 is a coreceptor for DT.

Decreased osteopontin expression in the rat kidney on a sodium deficient diet

Osteopontin (OPN) is a secreted phosphoprotein that is constitutively expressed in the normal kidney and is induced by various experimental and pathologic conditions. Several possible functions of OPN have been suggested, however the mechanism and significance of OPN expression are still uncertain. Since high salt concentration or salt crystal have been known to enhance OPN expression in intact kidney or cultured renal cells, in the present study we examined whether or not a low salt condition had an effect on OPN expression in the kidney. Adult male Sprague-Dawley rats were fed either a normal sodium or a sodium deficient diet for 1 week. Kidneys were processed for in situ hybridization using a digoxigenin-labeled riboprobe and for immunohistochemistry using antibodies to OPN, renin, and Na-K-ATPase. In rats fed a normal sodium diet, OPN mRNA and protein were expressed only in the descending thin limbs of Henle's loop (DTL) and in the papillary and pelvic surface epithelium (PSE). In rats fed a sodium deficient diet, there was a marked decrease in OPN immunoreactivity in the DTL, but no changes in PSE. In contrast, no changes were observed in OPN mRNA expression in the DTL by in situ hybridization, indicating that decreased OPN protein expression was a result of translational regulation. As expected, rats fed a sodium deficient diet were associated with increased immunoreactivity for Na-K-ATPase and renin compatible with activation of the renin-angiotensin system. These results suggest that dietary sodium may be involved in the regulation of OPN expression in the DTL of the rat kidney.

Ganglion cells of the rat retina show osteopontin-like immunoreactivity

Osteopontin (OPN) is a negatively charged, highly acidic glycosylated phosphoprotein that contains an GRGDS amino acid sequence, characteristic of proteins that bind to integrin receptors, thereby playing crucial roles in a number of physiological processes. This study was conducted to examine the expression of OPN in the rat retina by Northern blot analysis, Western blot analysis and immunocytochemistry. The expression of OPN was identified in the retina and OPN-like immunoreactivity was present in a number of ganglion cells. Thus, OPN appears to be important in the retinal homeostasis.

Intranuclear inclusions in subtypes of striatal neurons in Huntington's disease transgenic mice

R6/2 transgenic mice express exon 1 of an abnormal human Huntington's disease (HD) gene and develop a neurological phenotype similar to HD. These mice develop ubiquitinated neuronal intranuclear inclusions (NII) which might play a central role in the pathophysiology of HD. We studied the distribution of NII in subpopulations of striatal neurons in 12-week-old R6/2 transgenic mice using fluorescent double label immunohistochemistry. We observed that most of the Calbindin-D28K positive projection neurons (89%) and the Parvalbumin positive interneurons (86%) showed ubiquitinated NII. In interneurons, however, which contain either choline acetyltransferase, neuronal nitric oxide synthase, or Calretinin, the frequency of NII was much lower (22%, 8%, 9%, respectively). Our data suggest that subpopulations of striatal neurons differ remarkably in their capability of forming ubiquitinated NII. Interneurons which are known to resist neurodegeneration in HD show less NII.

Binding affinities of 3-(3-phenylisoxazol-5-yl)methylidene-1-azabicycles to acetylcholine receptors

A series of 3-(3-phenylisoxazol-5-yl)methylidene-1-azabicycles synthesized showed different binding characteristics to acetylcholine receptors depending on the substituents on the phenyl ring. Small polar substituents gave preferential binding affinity to nicotinic receptors, and large hydrophobic substituents to muscarinic receptors.

Expression of osteopontin mRNA in the adult rat brain

Examining the distribution of osteopontin (OPN) in the rat brain using in situ hybridization, it was found that OPN mRNA was restricted to likely neurons in the olfactory bulb and the brain stem; it was not detected in the telencephalon and the diencephalon. In addition, Northern blot analysis showed a confined expression only in the brain stem with higher level in the pons and the medulla than in the midbrain. In the brain stem, it was found in functionally diverse areas including motor-related areas, sensory system and reticular formation. This specific but widespread distribution suggests that OPN may play an important role in the adult rat brain.

[Huntington chorea. Animal models reveal new hypotheses for pathophysiology and therapy]

Huntington's disease (HD) is member of a growing family of neurodegenerative diseases which are caused by a CAG-Triplet expansion in the coding region of their respective genes. The results of the research of the last years is very suggestive of a common pathomechanisms of all these diseases even though their clinical appearance may be quite different. The development of new animal models by transferring the human gene defect into the mouse genome has led to the finding of so-called intranuclear inclusion bodies. This new observation allowed to come closer to solving the problem how this genetic defect causes neurodegeneration. Recent studies on transgenic HD mice could also demonstrate a possible connection between the genetic defect and glutamate exitotoxicity in the neurodegenerative process of HD which had been emphasized by earlier animal models of the disease. Transgenic animal models of HD will have an important impact on the understanding of the disease mechanisms and may contribute to a faster development and testing of new therapeutic approaches.

Transient upregulation of osteopontin mRNA in hippocampus and striatum following global forebrain ischemia in rats

We investigated the spatial and temporal expression of osteopontin (OPN) mRNA following transient forebrain ischemia in rats. Experiments were carried out using a four-vessel occlusion model for forebrain ischemia. The transient induction of OPN mRNA after global ischemia occurred earlier in the striatum than in the hippocampus. It was pronounced in the dorsomedial striatum close to the lateral ventricle and in the CA1 subfield and the subiculum of the hippocampus before microglial cells became more reactive. It also could be detected in the dentate hilus and to a marginal extent in the CA3. Our results suggest that the hippocampus and the striatum following global forebrain ischemia upregulate OPN mRNA in different spatiotemporal profiles.

Molecular cloning and expression analysis of a mouse phospholipase C-delta1

We describe here the molecular cloning and expression analysis of mouse PLC-delta1 (mPLC-delta1), a key enzyme in cell signal transduction. A mouse brain cDNA library was screened in order to isolate the mPLC-delta1 cDNA. The mPLC-delta1 cDNA was 2660 bp in length. The predicted open reading frame encodes a protein of 756 amino acids with an estimated molecular mass of 85 kDa. The deduced amino acid sequence exhibits 96.9% and 92.7% identity with the sequence of rat and human PLC-delta1, respectively. The mPLC-delta1 mRNA was highly expressed in brain, heart, lung, and testis. We found that transcripts of mPLC-delta1 are present in almost all regions of mouse brain examined, implying that the enzyme may play a role in some fundamental cellular process in brain. In male reproductive tract, mPLC-delta1 mRNA was widely expressed in the epididymis as well as in the testis. In situ hybridization studies indicate that distribution of mPLC-delta1 mRNA in mouse testis is discrete and unique. The expression of mPLC-delta1 mRNA was defined in the periphery of each seminiferous tubule, especially in spermatogonia, which might imply that mPLC-delta1 plays a role in proliferation of spermatogonia. To the best our knowledge, this is the first report to demonstrate the high expression of mPLC-delta1 mRNA in spermatogonia of testis. Taken together, these results suggest that mPLC-delta1 may carry out fundamental roles in almost all of mouse tissues, especially in brain and specific roles in testis.

Intracisternal antisense oligonucleotide to growth associated protein-43 blocks the recovery-promoting effects of basic fibroblast growth factor after focal stroke

Focal infarction (stroke) of the lateral cerebral cortex of rats (including the sensorimotor cortex) produces deficits in sensorimotor function of the contralateral limbs that recover partially over time. In previous studies, we found that the intracisternal injection of basic fibroblast growth factor (bFGF), a potent neurotrophic growth factor, starting at 1 day after stroke, significantly enhanced recovery of sensorimotor function of the contralateral forelimb and hindlimb. Moreover, immunoreactivity (IR) for growth-associated protein-43 (GAP-43), a molecular marker of new axonal growth, was increased in the intact contralateral sensorimotor cortex following bFGF treatment. In the current study, we found that the intracisternal administration of antisense, but not missense, oligonucleotide to GAP-43 blocked the recovery-enhancing effects of bFGF and blocked the increase in GAP-43 IR in the contralateral cortex. These results suggest that upregulation of GAP-43 expression and consequent enhanced axonal sprouting in intact uninjured parts of the brain are likely mechanisms for the recovery-promoting effects of bFGF.

Altered neurotransmitter receptor expression in transgenic mouse models of Huntington's disease

Alterations in neurotransmitter receptors are a pathological hallmark of the neurodegeneration seen in Huntington's disease (HD). However, the significance of these alterations has been uncertain, possibly reflecting simply the loss of brain cells. It is not known for certain whether the alteration of neurotransmitter receptors occurs before the onset of symptoms in human HD. Recently we developed transgenic mice that contain a portion of a human HD gene and develop a progressive abnormal neurological phenotype. Neurotransmitter receptors that are altered in HD (receptors for glutamate, dopamine, acetylcholine and adenosine) are decreased in the brain transgenic mice, in some cases before the onset of behavioural or motor symptoms. In transgenic mice, neurotransmitter receptor alterations occur before neuronal death. Further, receptor alterations are selective in that certain receptors, namely N-methyl-D-aspartate and gamma-aminobutyric acid receptors, are unaltered. Finally, receptor decreases are preceded by selective decreases in the corresponding mRNA species, suggesting the altered transcription of specific genes. These results suggest that (i) receptor decreases precede, and therefore might contribute to, the development of clinical symptoms, and (ii) altered transcription of specific genes might be a key pathological mechanism in HD.

Inhibition of caspase-1 slows disease progression in a mouse model of Huntington's disease

Huntington's disease is an autosomal-dominant progressive neurodegenerative disorder resulting in specific neuronal loss and dysfunction in the striatum and cortex. The disease is universally fatal, with a mean survival following onset of 15-20 years and, at present, there is no effective treatment. The mutation in patients with Huntington's disease is an expanded CAG/polyglutamine repeat in huntingtin, a protein of unknown function with a relative molecular mass of 350,000 (M(r) 350K). The length of the CAG/polyglutamine repeat is inversely correlated with the age of disease onset. The molecular pathways mediating the neuropathology of Huntington's disease are poorly understood. Transgenic mice expressing exon 1 of the human huntingtin gene with an expanded CAG/polyglutamine repeat develop a progressive syndrome with many of the characteristics of human Huntington's disease. Here we demonstrate evidence of caspase-1 activation in the brains of mice and humans with the disease. In this transgenic mouse model of Huntington's disease, expression of a dominant-negative caspase-1 mutant extends survival and delays the appearance of neuronal inclusions, neurotransmitter receptor alterations and onset of symptoms, indicating that caspase-1 is important in the pathogenesis of the disease. In addition, we demonstrate that intracerebroventricular administration of a caspase inhibitor delays disease progression and mortality in the mouse model of Huntington's disease.

Expression of vascular endothelial growth factor mRNA following transient forebrain ischemia in rats

Using a reproducible two-vessel occlusion model for forebrain ischemia in rats, we investigated the temporal and spatial changes of vascular endothelial growth factor (VEGF) expression after transient forebrain ischemia with Northern blot analysis and in situ hybridization. Northern blot analysis revealed that VEGF mRNA of the hippocampus was increased from 12 h after reperfusion, with a peak at 1 day. In situ hybridization and double labeling for VEGF mRNA and glial fibrillary acidic protein showed a transient induction of VEGF mRNA in the neurons of the hippocampus from 12 h of reperfusion with a peak at 1 day, and in the astrocytes of the hippocampus, caudoputamen, thalamus and cortical regions at 1 day. After 3 days, no more VEGF signal was detected. Our results demonstrate that astrocytes and neurons each upregulate VEGF mRNA in different temporal and spatial patterns after transient forebrain ischemia in the rat, and these patterns appear to be different from those in transient focal cerebral ischemia.

Hamster diphtheria toxin receptor: a naturally occurring chimera of monkey and mouse HB-EGF precursors

The sensitivity of mammalian cell lines to diphtheria toxin (DT) varies between species. Monkey (Mk) Vero cells are highly sensitive to DT, whereas rat and mouse (Ms) cells are resistant; hamster (Hm) cells display moderate DT sensitivity. The precursor of the Mk heparin-binding epidermal growth factor-like growth factor (proHB-EGF) functions as a DT receptor but the Ms proHB-EGF does not. In this study we have cloned, expressed, and characterized the Hm proHB-EGF/DT receptor. The expression of Hm proHB-EGF confers moderate DT sensitivity to normally DT-resistant mouse cells. The amino acid sequence of Hm preproHB-EGF shows that, overall, it more closely resembles the Ms preproHB-EGF sequence, except in the DT-binding region where it more closely resembles the Mk sequence. In the DT-binding region the Hm proHB-EGF sequence differs from the Mk proHB-EGF in only four amino acid residues (124, 126, 133, and 147); one of these residues, Ile133 in Mk proHB-EGF, has been previously reported to be important for DT binding and sensitivity. Analysis of Mk proHB-EGF mutants with residues substituted for Ile133 suggests that Asn133 in Hm proHB-EGF may be responsible for the moderate DT sensitivity of Hm proHB-EGF-expressing cells.

Intercalated cell subtypes in connecting tubule and cortical collecting duct of rat and mouse

At least two populations of intercalated cells, type A and type B, exist in the connecting tubule (CNT), initial collecting tubule (ICT), and cortical collecting duct (CCD). Type A intercalated cells secrete protons via an apical H+-ATPase and reabsorb bicarbonate by a band 3-like Cl-/HCO3-exchanger, AE1, located in the basolateral plasma membrane. Type B intercalated cells secrete bicarbonate by an apical Cl-/HCO3- exchanger that is distinct from AE1 and remains to be identified. They express H+-ATPase in the basolateral plasma membrane and in vesicles throughout the cytoplasm. A third type of intercalated cell with apical H+-ATPase, but no AE1, has been described in the CNT and CCD of both rat and mouse. The prevalence of the third cell type is not known. The aim of this study was to characterize and quantify intercalated cell subtypes, including the newly described third non A-non B cell, in the CNT, ICT, and CCD of the rat and mouse. A triple immunolabeling procedure was developed in which antibodies to H+-ATPase and band 3 protein were used to identify subpopulations of intercalated cells, and segment-specific antibodies were used to identify distal tubule and collecting duct segments. In both rat and mouse, intercalated cells constituted approximately 40% of the cells in the CNT, ICT, and CCD. Type A, type B, and non A-non B intercalated cells were observed in all of the three segments, with type A cells being the most prevalent in both species. In the mouse, however, non A-non B cells constituted more than half of the intercalated cells in the CNT, 39% in the ICT, and 22% in the CCD, compared with 14, 7, and 5%, respectively, in the rat. In contrast, type B intercalated cells accounted for only 8 to 16% of the intercalated cells in the three segments in the mouse compared with 26 to 39% in the rat. It is concluded that striking differences exist in the prevalence and distribution of the different types of intercalated cells in the CNT, ICT, and CCD of rat and mouse. In the rat, the non A-non B cells are fairly rare, whereas in the mouse, they constitute a major fraction of the intercalated cells, primarily at the expense of the type B intercalated cells.

Distributional patterns of phospholipase C isozymes in rat kidney

As the first step to investigate the physiological function of phospholipase C (PLC), we determined the distribution patterns of PLC isozymes in normal rat kidneys using Western blotting analysis and immunohistochemistry. Western blotting analysis was performed in four regions (cortex, outer stripe and inner stripe of the outer medulla, and the inner medulla). PLC-beta1 and beta3 were detected in the inner stripe of the outer medulla and the inner medulla. PLC-gamma1 was distributed homogeneously along the corticomedullary axis. PLC-gamma2 was observed in the medulla and PLC-delta1 showed a gradual increase from the cortex to the inner medulla. In contrast, no PLC-beta4 was detected in all regions. On immunohistochemistry, the immunoreactivities to PLC antibodies were observed as follows: PLC-beta1, from the thick ascending limb (TAL) to the inner medullary collecting tubule (IMCT); PLC-beta3, in the glomerulus (Glm), the ascending thin limb (ATL) and the collecting tubule; PLC-beta4, Glm, the proximal convoluted tubule (PCT), ATL, the distal convoluted tubule, the connecting tubule, and the collecting tubules; PLC-gamma1, PCT, TAL and IMCT; PLC-delta1, homogeneously from PCT to IMCT. PLC-beta3 immunoreactivities were detected in the nuclei of the TAL, ATL, outer medullary collecting tubule (OMCT) and IMCT. PLC-beta4 and gamma2 were observed in Glm, MTAL, ATL, OMCT and IMCT. These results suggest the intrarenal site-specific existence of PLC isozymes that may regulate kidney functions through the PLC-mediated signal transductions.

Toxin binding site of the diphtheria toxin receptor: loss and gain of diphtheria toxin binding of monkey and mouse heparin-binding, epidermal growth factor-like growth factor precursors by reciprocal site-directed mutagenesis

The transmembrane precursor of the monkey (Mk) heparin-binding, epidermal growth factor-like growth factor (proHB-EGF) functions as a diphtheria toxin (DT) receptor, whereas the mouse (Ms) precursor does not. Previously, using chimeric Ms/Mk precursors, we have shown that DT resistance of cells bearing Ms proHB-EGF may be accounted for by several amino acid substitutions between residues 122 and 148 within the EGF-like domain and that Glu-141 is an important amino acid residue for DT binding. In this study, reciprocal site-directed mutagenesis was performed on the major non-conserved residues in the region of 122-148, alone or in combination, between Mk and Ms precursors to identify more precisely which amino acid residues are important for DT binding. Two approaches were used. The first, more traditional approach was to destroy DT sensitivity and binding of Mk proHB-EGF by substitution(s) with the corresponding Ms residue(s). From the single mutations, the greatest loss of DT sensitivity was observed with Mk/Glu-141His (approximately 4000-fold) and the next greatest with Mk/Ile-133Lys (approximately fourfold). The double mutations Mk/Leu-127Phe/Glu-141His, Mk/Ile-133Lys/Glu-141His and Mk/His-135Leu/Glu-141His resulted in complete toxin resistance (> 100000-fold). The second approach, both novel and complementary, was to gain DT binding and sensitivity of Ms proHB-EGF by substitution(s) with the corresponding Mk residue(s). Surprisingly, the single mutation Ms/His-141Glu resulted in the gain of moderate DT sensitivity (> 260-fold). The double mutation Ms/Lys-133Ile/His-141Glu and the triple mutation Ms/Lys-133Ile/Leu-135His/His-141Glu resulted in a progressive gain in toxin sensitivity (> 4700-fold and >16000-fold respectively) and affinity. This triple mutant cell line is essentially as sensitive (IC50 = 3.1 ng ml(-1)) as the highly toxin-sensitive monkey Vero cell line (IC50 = 4 ng ml(-1)), indicating that these three Mk residues enable the Ms proHB-EGF to act as a fully functional DT receptor. Taken together, these results indicate that Glu-141 plays the most critical role in DT binding and sensitivity and that two additional amino acid residues, Ile-133 and His-135, also play significant roles.

Inhibition of calbindin D28K expression by cyclosporin A in rat kidney: the possible pathogenesis of cyclosporin A-induced hypercalciuria

A recent study by Steiner et al. (Biochem Pharmacol 51: 253-258, 1996) demonstrated a decreased calbindin D28K expression in the kidneys of cyclosporin A (CsA)-treated rats. To evaluate the association of renal calcium handling with calbindin D28K expression in CsA-treated rats, two separate experiments (vehicle [VH] versus CsA groups, 1,25-dihydroxyvitamin D3 [VitD] versus VitD + CsA groups) were done simultaneously. CsA (25 mg/kg per d, subcutaneously) and VitD (0.5 microg/kg per d, subcutaneously) were given for 7 d. The CsA group showed decreased serum calcium, increased urine calcium excretion, and decreased calbindin D28K protein level and immunoreactivity compared with the VH group. The VitD + CsA treatment decreased serum calcium, increased urine calcium excretion, and decreased calbindin D28K protein level and immunoreactivity compared with the VitD alone. CsA treatment did not affect the serum parathyroid hormone and VitD levels. This study demonstrates an association of calbindin D28K expression with the urinary calcium excretion in CsA-treated rats, and suggests that decreased calbindin D28K expression may play a role in renal calcium wasting.

Diphtheria toxin:receptor interaction: association, dissociation, and effect of pH

Diphtheria toxin (DT) binds to a specific heparin-binding epidermal growth factor-like growth factor (HB-EGF) precursor that is expressed in DT-sensitive cells. DT binds to the cell-surface HB-EGF precursor with an apparent dissociation constant (KD) of approximately 1 x 10(-8) - 10(-9) M at 4 degreesC, a temperature at which toxin binds but is not internalized. The interaction of DT with the cell-surface receptor, however, may be influenced by other cell-surface components. We used a biosensor method to measure the binding of DT to immobilized recombinant human HB-EGF (hHB-EGF) at 25 degreesC with no other cellular components present. We observed that at pH 7.4, using this in vitro two component system, DT binds to hHB-EGF with an apparent KD of 2.7 x 10(-8) M. We also observed that the dissociation of DT from hHB-EGF at pH values that approach those of the endosome occurs at a faster rate as the pH is decreased. These results suggest that the low pH of the endosome is sufficient to allow DT to dissociate from the HB-EGF precursor, prior to the translocation of the enzymatically active fragment of DT into the cytosol.