Brain-mimicking phantom for biomechanical validation of motion sensitive MR imaging techniques

Motion sensitive MR imaging techniques allow for the non-invasive evaluation of biological tissues by using different excitation schemes, including physiological/intrinsic motions caused by cardiac pulsation or respiration, and vibrations caused by an external actuator. The mechanical biomarkers extracted through these imaging techniques have been shown to hold diagnostic value for various neurological disorders and conditions. Amplified MRI (aMRI), a cardiac gated imaging technique, can help track and quantify low frequency intrinsic motion of the brain. As for high frequency actuation, the mechanical response of brain tissue can be measured by applying external high frequency actuation in combination with a motion sensitive MR imaging sequence called Magnetic Resonance Elastography (MRE). Due to the frequency-dependent behavior of brain mechanics, there is a need to develop brain phantom models that can mimic the broadband mechanical response of the brain in order to validate motion-sensitive MR imaging techniques. Here, we have designed a novel phantom test setup that enables both the low and high frequency responses of a brain-mimicking phantom to be captured, allowing for both aMRI and MRE imaging techniques to be applied on the same phantom model. This setup combines two different vibration sources: a pneumatic actuator, for low frequency/intrinsic motion (1 Hz) for use in aMRI, and a piezoelectric actuator for high frequency actuation (30-60 Hz) for use in MRE. Our results show that in MRE experiments performed from 30 Hz through 60 Hz, propagating shear waves attenuate faster at higher driving frequencies, consistent with results in the literature. Furthermore, actuator coupling has a substantial effect on wave amplitude, with weaker coupling causing lower amplitude wave field images, specifically shown in the top-surface shear loading configuration. For intrinsic actuation, our results indicate that aMRI linearly amplifies motion up to at least an amplification factor of 9 for instances of both visible and sub-voxel motion, validated by varying power levels of pneumatic actuation (40%-80% power) under MR, and through video analysis outside the MRI scanner room. While this investigation used a homogeneous brain-mimicking phantom, our setup can be used to study the mechanics of non-homogeneous phantom configurations with bio-interfaces in the future.

Beneficial effects of balloon pulmonary angioplasty on clinical outcomes in patients with residual pulmonary hypertension after pulmonary endarterectomy

Background

Although pulmonary endarterectomy (PEA) is an established surgical treatment for chronic thromboembolic pulmonary hypertension (CTEPH), a part of patients after PEA show residual pulmonary hypertension, leading to limited exercise capacity. Recently, several studies have indicated that balloon pulmonary angioplasty (BPA) improves hemodynamics, exercise capacity and prognosis in inoperable CTEPH patients. However, the effects of BPA in patients with residual pulmonary hypertension after PEA remain to be elucidated.

Aim

In the present study, we investigated comprehensive efficacy of BPA on hemodynamics, exercise capacity and right ventricular function in those with residual pulmonary hypertension after PEA.

Methods

From October 2010 to February 2019, 227 patients with CTEPH underwent PEA in our institution. Right heart catheterization after PEA (median follow up period from PEA to right heart catheterization 39 [10.5, 90] months) showed that 55 patients showed residual PH (mean pulmonary artery pressure (mPAP)≥25mmHg), and 38 of them referred to BPA (mean age 57 years old, male 8 (21%)) due to residual symptoms. In 29 out of 38 patients (76%) who completed BPA and underwent follow-up right heart catheterization, we examined hemodynamics, exercise capacity and right ventricular function before and after BPA. Follow-up examination was performed 3 months after last BPA session.

Results

In this study population (N=29), PEA significantly improved mPAP (47±7 to 38±10 mmHg), pulmonary vascular resistance (PVR, 14.6±4.6 to 9.2±4.6 WU) and right ventricular ejection fraction measured by magnetic resonance imaging (26.6±11.3 to 38.4±6.8%) (Figure). Median period from PEA to first BPA procedure was 42 [13.5, 94] months. Total session number during study period was 160 sessions, and mean session number of BPA was 5.5±1.5 per patient. Follow-up study revealed that BPA additionally improved mPAP (38±10 to 27±8 mmHg) and PVR (9.2±4.6 to 5.1±2.2 WU) (Figure). Similarly, 6-minute walk distance (393±125 to 452±125 m) and peak VO2 (16.4±3.8 to 18.1±4.6 ml/min/kg, p<0.05) were increased, and WHO functional class also significantly improved by BPA (I/II/III/IV, 0/21/8/ 0 to 1/27/1/0, p<0.01). In addition, right ventricular ejection fraction (38.4±6.8 to 44.2±7.1%) was increased after BPA (Figure). There were no procedure-related deaths and major lung injuries requiring oral intubation during study period. 3-year survival in patients after BPA was 100% (median follow-up period after last BPA session, 32 [18, 46] months).

Conclusion

In CTEPH patients with residual pulmonary hypertension after PEA, additional BPA significantly improved hemodynamics, right ventricular function, exercise capacity and residual symptoms without severe complications, leading to good prognosis. These results suggest that combination therapy of PEA and BPA could be an effective therapeutic option for post PEA patients with residual symptoms and exercise limitation.

Figure 1

Funding Acknowledgement

Type of funding source: None

Effects of deep sedation under mechanical ventilation on cognitive outcome in patients undergoing surgery for oral and maxillofacial cancer and microvascular reconstruction

OBJECTIVE

Cognitive impairment after intensive care unit (ICU) admission is becoming increasingly recognized. High-dose deep sedation has been suggested to play an important role in the development of cognitive impairment. However, the impact of heavy sedation as a single cause in the development of cognitive impairment in ICU patients remains unclear. In this study we investigated whether a three-day deep sedation protocol could reduce cognitive function in mechanically ventilated non-critical patients.

DESIGN

A prospective observational study was carried out.

PATIENTS

A total of 17 surgical patients were studied.

INTERVENTION

None.

VARIABLES OF INTEREST

Cognitive function before and after ICU admission.

RESULTS

Thirty-one patients requiring three days of sedation after microvascular reconstruction were initially enrolled in the study. Sedation in the ICU was maintained with propofol and dexmedetomidine combined with fentanyl. Cognitive function was assessed using a battery of 6 neuropsychological tests two days before surgery and three weeks after surgery. Finally, a total of 17 patients were included in the analysis. Cognitive impairment (defined as a decline of >20% from the pre-admission cognitive evaluation scores in at least two of 6 tests) was observed in 5 of the 17 patients (29%). However, there were no significant differences between the pre- and post-admission cognitive evaluations in 6 tests.

CONCLUSIONS

Middle-term cognitive function can be impaired in some patients subjected to deep sedation during several days following maxillary-mandibular oral surgery with microvascular reconstruction.

Molecular cloning, polymorphism, and functional activity of the bovine and water buffalo Mx2 gene promoter region

Background

Bovine Mx2 gene sequences were already reported, but further information about the gene properties is not yet available. The objective of the current study was to elucidate the structural properties of the bovine Mx2 gene mainly the promoter region and its possible functional role. If available, such information would help in assessing the functional properties of the gene, which was reported to confer antiviral action against recombinant VSV.

Results

Examinations on the bovine genomic BAC clone—confirmed to contain the Mx2 gene—revealed 883-bp sequences. A computer scan unequivocally identified a 788-bp promoter region containing a typical TATA box, three ISREs and other promoter-specific motifs. Comparative analysis of nine bovine genomic DNA samples showed 19 nucleotide substitutions suggesting the existence of five different genotypes in the promoter region. The water buffalo Mx2 promoter region was determined by using primers based on the bovine Mx2 promoter region disclosing 893-bp, with 56 substitutions, two insertions, 9 and 1 nt at two different sites. A functional analysis of the putative ISRE indicated that ISRE played a synergetic role in the activation of bovine Mx2 gene transcription.

Conclusion

Bovine and water buffalo Mx2 promoter region was identified disclosing, the conserved ISRE, located in the proximal end of the promoter region like other members of the antiviral family, suggesting functional activity under interferon stimulation.

An original technique for lymph node dissection along the left recurrent laryngeal nerve after stripping the residual esophagus during video-assisted thorocoscopic surgery of esophagus

BACKGROUND

A clear operative view of the middle and lower mediastinum is possible in prone position during video-assisted thorocoscopic surgery of esophagus (VATS-E), but the working space in the upper mediastinum is limited and lymph node dissection along the left recurrent laryngeal nerve (RLN) is difficult in this position.

METHODS

Esophagectomy and lymph node dissection are performed for pneumothorax by maintaining CO₂ insufflation in the prone position. Working space in the left upper mediastinal area for lymph node dissection around RLN is limited in this position. To create space, the residual esophagus is stripped in the reverse direction and retracted toward the neck after the stomach tube is removed through the nose. Lymph node dissection is performed after stripping the residual esophagus.

RESULTS

We could obtain a clear operative field in the upper left mediastinum by stripping the residual esophagus in the prone position, enabling safe and straightforward lymph node dissection along the left RLN. The rate of permanent RLN paralysis was 1.2%.

CONCLUSIONS

Lymph node dissection along the left RLN after esophageal stripping is possible in the prone position during VATS-E.

Distribution of Water, Fat, and Metals in Normal Liver and in Liver Metastases Influencing Attenuation on Computed Tomography

The quantity of water, lipid and some metals was measured in autopsy specimens of 8 normal livers, 9 livers with fatty change, and in 12 livers with metastases of various origins. These parameters contribute to the CT number measured in the liver. Water played a major role in demonstration of liver metastases as a low-density area on CT. Other contributory factors include iron, magnesium and zinc. Lipid and calcium had no influence in this respect. Heavy accumulation of calcium in a metastatic lesion gives a high-density area on CT. However, even when a metastatic lesion was perceived on CT as a low-density area, the calcium content of the lesion was not always lower than that of the non-tumour region.

Effect of Intravenous Contrast Media on Proximal and Distal Tubular Hydrostatic Pressure in the Rat Kidney

The effect of i.v. injection of contrast media (CM, 1 600 mg I/kg b.w.) on proximal and distal tubular hydrostatic pressure (PTHP, DTHP) in the rat was investigated using a micropuncture technique. The PTHP and DTHP after injection of diatrizoate, iohexol, ioxaglate, or mannitol returned to control values within approximately 20 min. However, following iotrolan injection PTHP was still elevated above control levels after 35 min while DTHP remained elevated throughout the experiment (50 min). Iotrolan has a lower osmotic potential than the other CM when given in equivalent iodine doses. The concentration of iotrolan may thus increase more along the tubules than the other CM and consequently lead to a higher viscosity of urine, resulting in increases in PTHP and DTHP. The high intratubular pressure induced by iotrolan may explain our previous findings of reduced single nephron glomerular filtration rate caused by this CM.

Spectroscopic properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 and Y3Ga5O12 at ambient and high hydrostatic pressure

In this study, we present optical properties and location of the Ce3+ energy levels in Y3Al2Ga3O12 (YAGG) and Y3Ga5O12 (YGG) ceramics at ambient and high hydrostatic pressure.

Close relationships between polar auxin transport and graviresponse in plants

Gravitational force on Earth is one of the major environmental factors affecting plant growth and development. Spacecraft and the International Space Station (ISS), and a three-dimensional (3-D) clinostat have been available to clarify the effects of gravistimulation on plant growth and development in space and on ground conditions, respectively. Under a stimulus-free environment such as space conditions, plants show a growth and developmental habit designated as 'automorphosis' or 'automorphogenesis'. Recent studies in hormonal physiology, together with space and molecular biology, have demonstrated the close relationships between automorphosis and polar auxin transport. Reduced polar auxin transport in space conditions, or induced by the application of polar auxin transport inhibitors, substantially induced automorphosis or automorphosis-like growth and development, indicating that polar auxin transport is responsible for graviresponse in plants. This concise review covers graviresponse in plants and automorphosis observed in space conditions, and polar auxin transport related to graviresponse in etiolated Alaska and ageotropum pea seedlings. Molecular aspects of polar auxin transport clarified in recent studies are also described.

Epithelial splicing regulatory protein 1 is a favorable prognostic factor in pancreatic cancer that attenuates pancreatic metastases

Epithelial splicing regulatory protein 1 (ESRP1) binds the FGFR-2 auxiliary cis-element ISE/ISS-3, located in the intron between exon IIIb and IIIc, and primarily promotes FGFR-2 IIIb expression. Here we assessed the role of ESRP1 in pancreatic ductal adenocarcinoma (PDAC). Immunohistochemical analysis was performed using anti-ESRP1, FGFR-2 IIIb and FGFR-2 IIIc antibodies in 123 PDAC cases. ESRP1-expression vector and small interference RNA (siRNA) targeting ESRP1 were transfected into human PDAC cells, and cell growth, migration and invasion were analyzed. In vivo heterotopic and orthotopic implantations using ESRP1 overexpression clones were performed and effects on pancreatic tumor volumes and hepatic and pulmonary metastases determined. ESRP1 immunoreactivity was strong in the nuclei of cancer cells in well-to-moderately differentiated PDACs, but weak in poorly-differentiated cancers. Well-to-moderately differentiated cancers also exhibited high FGFR-2 IIIb and low FGFR-2 IIIc expression, whereas this ratio was reversed in the poorly-differentiated cancers. Increased ESRP1 expression was associated with longer survival by comparison with low-ESRP1 expression, and PANC-1 cells engineered to express ESRP1 exhibited increased FGFR-2 IIIb expression and decreased migration and invasion in vitro, whereas ESRP1 siRNA-transfected KLM-1 cells exhibited increased FGFR-2 IIIc expression and increased cell growth, migration and invasion. In vivo, ESRP1-overexpressing clones formed significantly fewer liver metastases as compared with control clones. ESRP1 regulates the expression pattern of FGFR-2 isoforms, attenuates cell growth, migration, invasion, and metastasis, and is a favorable prognostic factor in PDAC. Therefore, devising mechanisms to up-regulate ESRP1 may exert a beneficial therapeutic effect in PDAC.

Polymorphism of acid phosphatase in chicken leucocytes

Three individual variants of acid phosphatase in chicken leucocytes were found by means of starch gel electrophoresis. The phenotype in leucocytes showed the same appearance as polymorphic forms of liver acid phosphatase in the same bird. The study of the Hardy-Weinberg distribution of the phenotypes of acid phosphatase in leucocytes also indicated that they are controlled by the same pair of codominant autosomal alleles as the phenotypes in the liver. Acid phosphatase is polymorphic in all six strains of chickens studied.

Polymorphisms in the promoter region of the porcine antiviral MX1 and MX2 genes

The porcine MX1 and MX2 promoters were characterized in this study. Sequencing of the 332-bp MX1 promoter region identified 15 substitutions and insertions at three positions in 21 pigs from 15 breeds, in which nine genotypes were classified. Among the nine genotypes, no statistically significant differences in the promoter activities were observed after interferon (IFN-alpha 2b) treatment of transiently transfected cells containing constructs with luciferase reporter plasmids. The 341-bp MX2 promoter region contained regulatory sequences for ISRE, GC box, Sp1 and AP-1, as well as a TATA box. Nucleotide sequences of the MX2 promoter region revealed four substitutions and one deletion, in which six genotypes were classified. Among the six genotypes, a statistically significant difference (P < 0.05) in MX2 promoter activities after IFN-alpha 2b treatment was detected in transiently transfected cells.

Bovine and water buffalo Mx2 genes: polymorphism and antiviral activity

Millennia-long selective pressure of single-strand RNA viruses on the bovine Mx locus has increased the advantages of using the bovine Mx protein to evaluate the ultimate significance of the antiviral role of Mx proteins. The conclusions of research based only on the bovine Mx1 protein showed the need for comprehensive studies that demonstrate the role of all isoforms, individually or together, especially in the presence of a second isoform, the bovine Mx2 gene. This study provides information about bovine and water buffalo Mx2 genes, as well as their allelic polymorphism and basic antiviral potential. Observation of an Mx2 cDNA sequence (2,381 bp) obtained from 15 animals from 11 breeds using primers based on a previous sequence (NCBI accession no. AF335147) revealed several nucleotide substitutions, with eight different alleles and two amino acid exchanges: Gly to Ser at position 302 and Ile to Val at position 354, though the latter was found only in the NCBI database. A water buffalo Mx2 cDNA sequence was identified for the first time, revealing 46 nucleotide substitutions with 12 amino acid variations, in addition to a 9-bp insertion in the 5' untranslated region UTR, compared with the bovine Mx2 cDNA. Transfected 3T3 cells expressing bovine Mx2 mRNAs coding Gly or Ser at position 302, water buffalo Mx2 mRNA, positive control bovine Mx1 mRNA-expressing cells, and negative control parental 3T3 were subjected to infection with recombinant vesicular stomatitis virus (VSVDeltaG*-G), as were empty pCI-neo vector-transfected cells. The positive control and all cells expressing Mx2 mRNAs displayed significantly higher levels of antiviral activity against VSVDeltaG*-G (P < 0.01) than did the negative controls.

Population Research of Genetic Polymorphism at Amino Acid Position 631 in Chicken Mx Protein with Differential Antiviral Activity

A single amino acid substitution between Asn and Ser at position 631 in the chicken Mx protein has been reported to determine resistant and sensitive antiviral activity. In this study, we investigate whether various kinds of chicken breeds and jungle fowls carry the resistant or sensitive Mx allelic gene by using the mismatched PCR-restriction fragment length polymorphism (RFLP) technique. In total, 271 samples from 36 strains of 17 chicken breeds and from 3 kinds of jungle fowls were examined. The rates of the resistant Mx gene and sensitive gene were 59.2% and 40.8%, respectively. Only a Red jungle fowl captured in Laos carried the resistant Mx gene, and the other three Red jungle fowls from Indonesia and Gray and Green jungle fowls all had the sensitive Mx gene. These results were confirmed by the determination of amino acid sequences in the GTPase effector domain of jungle fowls.

Topically administered timolol and dorzolamide reduce intraocular pressure and protect retinal ganglion cells in a rat experimental glaucoma model

AIMS

This study sought to elucidate the effects of timolol and dorzolamide on intraocular pressure (IOP) and retinal ganglion cell (RGC) death in an experimental model of glaucoma in rat.

METHODS

Mild elevation of IOP was induced in rats by intracameral injection of India ink and subsequent laser trabecular photocoagulation. IOP was measured before the surgical procedures and weekly thereafter. Timolol (0.5%), timolol XE (0.5%), dorzolamide (1%), and artificial tears (vehicle) were topically applied daily. Retinal sections were prepared for histology to determine RGC number.

RESULTS

Timolol, timolol XE, and dorzolamide induced a significant reduction in IOP (p<0.05) and counteracted the reduction in RGC number that occurred in vehicle treated glaucomatous eyes (p<0.05). The coefficient of correlation between RGC number and IOP was significant in the dorzolamide treated group (r = -0.908, p<0.005), but not in other groups (p>0.05).

CONCLUSIONS

Both timolol formulation and dorzolamide reduced IOP and protected RGCs in a rat model of experimental glaucoma. It cannot be ruled out that timolol might protect RGCs by additional mechanisms other than simply lowering of IOP.

Genetic polymorphisms and antiviral activity in the bovine MX1 gene

Bovine MX1 cDNAs consisting of 2280 bp from 11 animals of five breeds and from a cultured cell line were sequenced and compared with previously reported data. Ten nucleotide substitutions were synonymous mutations, and a single nucleotide substitution at 458 resulted in an amino acid exchange of Ile (ATT) and Met (ATG). A 13-bp deletion-insertion mutation was also found in the 3'-UTR. Based on the nucleotide substitutions found in this study, bovine MX1 cDNA was classified into 11 genotypes. A phylogenetic tree of the 11 genotypes suggested that the genotypes observed in Brahman were a great genetic distance from other genotypes. An 18-bp deletion-insertion variation at position 171 was found to be the result of alternative splicing. The 18-bp deletion-insertion is located at the boundary between exon 3 and intron 3. Permanently transfected 3T3 cell lines expressing bovine MX1 mRNA were established to analyse the antiviral potential against VSVDeltaG*-G infection. Transfected cell clones expressing bovine MX1 mRNA showed a significantly smaller number of cells infected with VSVDeltaG*-G compared with the control cells. These results indicate that the bovine MX1 protein has potent antiviral activity.

Detection of Japanese yam mosaic virus by RT-LAMP

Arapid and simple procedure is described to detect the genomic RNA molecule of Japanese yam mosaic potyvirus (JYMV). This method, named RT-LAMP, allows direct detection of RNA from infected plants without careful RNA extraction, rapid thermal cycling and gel electrophoresis. RT-LAMP was successfully applied to leaves, propagules and roots of Japanese yam infected with JYMV. One of the characteristics of the RT-LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of by-product, pyrophospate ion, is produced yielding a white precipitate of magnesium pyrophosphate in the reaction mixture. The presence or absence of this white precipitate allows easy detection of the amplification of JYMV genomic RNA without gel electrophoresis.

Urinary metabolites of genistein administered orally to rats

In a study on the metabolism of flavonoids, the isoflavone genistein was administered orally to rats. Urine samples were collected and treated with beta-glucuronidase and arylsulfatase. Genistein and its metabolites, 4',5,7-trihydroxyisoflavanone (M1), 4',7-dihydroxyisoflavan (M2), and p-ethylphenol (M3) were isolated from the urine following treatment with enzymes. The structures of M1, M2, and M3 were determined on the basis of chemical and spectral data.

Distribution and expression of transforming growth factor-beta and platelet-derived growth factor in the normal and glaucomatous monkey optic nerve heads

PURPOSE

Remodeling of the extracellular matrix occurs in the lamina cribrosa in progressed glaucomatous optic nerve damage including disc cupping. We examined immunohistochemical changes in the transforming growth factor (TGF)-beta and platelet-derived growth factor (PDGF) in the optic nerve head in an experimentally induced glaucoma model.

METHODS

We used 3 cynomolgus and 2 Japanese monkey eyes. Glaucoma was induced by repeated argon laser photocoagulation of the chamber angle. Eyes were enucleated after disc cupping had formed 3 to 5 months after photocoagulation. The optic nerve head was examined for expression of TGF-beta1, -beta2 and -beta3 and PDGF-A and -B in frozen sections and by the biotin ExtraAvidin-alkali phosphatase method.

RESULTS

Normal monkey eyes showed TGF-beta1, -beta2 and -beta3, and PDGF-A and -B in the optic nerve head including the nerve fibers, glial cells, and vascular cells. Glaucomatous eyes showed stronger expression of TGF-beta1 and -beta2 in the glial cells around the lamina cribrosa. The staining intensities for TGF-beta3, PDGF-A and -B were the same as in normal eyes.

CONCLUSIONS

Eyes with experimental glaucoma showed higher expression of TGF-beta1 and -beta2 around the lamina cribrosa. These findings may show upregulation of extracellular matrix production as related to remodeling of the lamina cribrosa in glaucoma.

The DEFECTIVE IN ANTHER DEHISCIENCE gene encodes a novel phospholipase A1 catalyzing the initial step of jasmonic acid biosynthesis, which synchronizes pollen maturation, anther dehiscence, and flower opening in Arabidopsis

The Arabidopsis mutant defective in anther dehiscence1 (dad1) shows defects in anther dehiscence, pollen maturation, and flower opening. The defects were rescued by the exogenous application of jasmonic acid (JA) or linolenic acid, which is consistent with the reduced accumulation of JA in the dad1 flower buds. We identified the DAD1 gene by T-DNA tagging, which is characteristic to a putative N-terminal transit peptide and a conserved motif found in lipase active sites. DAD1 protein expressed in Escherichia coli hydrolyzed phospholipids in an sn-1-specific manner, and DAD1-green fluorescent protein fusion protein expressed in leaf epidermal cells localized predominantly in chloroplasts. These results indicate that the DAD1 protein is a chloroplastic phospholipase A1 that catalyzes the initial step of JA biosynthesis. DAD1 promoter::beta-glucuronidase analysis revealed that the expression of DAD1 is restricted in the stamen filaments. A model is presented in which JA synthesized in the filaments regulates the water transport in stamens and petals.

The DEFECTIVE IN ANTHER DEHISCIENCE gene encodes a novel phospholipase A1 catalyzing the initial step of jasmonic acid biosynthesis, which synchronizes pollen maturation, anther dehiscence, and flower opening in Arabidopsis

The Arabidopsis mutant defective in anther dehiscence1 (dad1) shows defects in anther dehiscence, pollen maturation, and flower opening. The defects were rescued by the exogenous application of jasmonic acid (JA) or linolenic acid, which is consistent with the reduced accumulation of JA in the dad1 flower buds. We identified the DAD1 gene by T-DNA tagging, which is characteristic to a putative N-terminal transit peptide and a conserved motif found in lipase active sites. DAD1 protein expressed in Escherichia coli hydrolyzed phospholipids in an sn-1-specific manner, and DAD1-green fluorescent protein fusion protein expressed in leaf epidermal cells localized predominantly in chloroplasts. These results indicate that the DAD1 protein is a chloroplastic phospholipase A1 that catalyzes the initial step of JA biosynthesis. DAD1 promoter::beta-glucuronidase analysis revealed that the expression of DAD1 is restricted in the stamen filaments. A model is presented in which JA synthesized in the filaments regulates the water transport in stamens and petals.

Keratocan expression is increased in the stroma of keratoconus corneas

BACKGROUND

Keratoconus is a noninflammatory disease characterized by thinning and scarring of the central portion of the cornea. The etiology is unclear. In this study, we sought to identify mRNAs that are differentially expressed in the stroma of keratoconus corneas in comparison to those of corneas from normal individuals and patients with other corneal diseases.

MATERIALS AND METHODS

Total RNA was isolated from the stromal layer of normal human, keratoconus, and pseudophakic bullous keratopathy corneas. cDNA was synthesized and PCR-select subtractive hybridization experiments were performed. The differentially expressed genes noted were verified by dot blot analysis, cloned, and sequenced. Immunohistochemical staining, in situ hybridization, and/or reverse transcription polymerase chain reaction were used to assess expression of the identified genes at protein and/or mRNA levels in normal, keratoconus, and other diseased corneas.

RESULTS

A number of genes were found to be up-regulated in keratoconus specimens. These included heat shock protein 90, decorin, fibronectin, ferritin heavy chain, and keratocan. Among them, keratocan mRNA transcript and protein were demonstrated to be expressed at a higher level specifically in the keratoconus stroma.

CONCLUSIONS

Keratocan expression in the stoma was increased in keratoconus corneas. This up-regulation appears to be keratoconus specific. Keratocan is one of the three keratan sulfate proteoglycans in the cornea speculated to be important for structure of the stromal matrix and maintenance of corneal transparency. The overexpressed keratocan may conceivably alter the fibrillogenesis in the stroma, leading to structural defects and contributing to the development of keratoconus.

Cell adhesion glycoproteins in the human lamina cribrosa

PURPOSE

The distribution of the cell adhesion glycoproteins, laminin, fibronectin, tenascin, vitronectin, thrombospondin, and entactin/nidogen, was examined in the human lamina cribrosa.

METHODS

Frozen sections of the optic nerve head from 7 normal human elderly donors were stained by immunohistochemistry.

RESULTS

All six glycoproteins were detected in this tissue. While laminin and entactin/nidogen were observed linearly, reflecting the localization of basement membranes, fibronectin was identified diffusely. Marked tenascin immunoreactivity was apparent in the lamina cribrosa, but little or no tenascin staining was detected in the sclera. Vitronectin showed a fine fibrillar staining pattern in the lamina cribrosa, and, to a lesser extent, in the sclera and pial septa. Thrombospondin staining was apparent only in the sclera and the lamina cribrosa, which traversed the optic nerve.

CONCLUSIONS

These results indicate that extracellular matrix components in the lamina cribrosa differ from those in the sclera or pial septa. This study is the first report that the human lamina cribrosa includes vitronectin and thrombospondin.

The usefulness and limits of magnetic resonance imaging in the differential diagnosis of pelvic tumors

Three cases of benign pelvic tumors are presented (2 leiomyomas and 1 fibroma). All three tumors were suspected of being malignant neoplasms because they were visualized as heterogeneous high signal intensity on T2-weighted images, and thus they were difficult to diagnose preoperatively. One of the leiomyomas was located in the retroperitoneum and had been misdiagnosed as an ovarian tumor. All three tumors exhibited secondary myxoid changes, these changes may have been responsible for the high signal intensity on the T2-weighted MR images. Since benign tumors sometimes mimic malignant tumors on MR images, exploratory laparotomy is essential to make a definitive diagnosis.

Comparative immunochemical study of lectin-binding sites and cytoskeletal filaments in static and reactive mesothelium and adenocarcinoma

In cytological preparations, reactive mesothelial cells (RMC) in serous effusions are sometimes difficult to distinguish from adenocarcinoma cells (AC). RMC and AC can be distinguished by lectin-binding patterns, but the pattern of binding of lectins to normal mesothelium is not well defined. We investigated the expression of cytoskeletal filaments, cytokeratin (CK) and vimentin (VM), and the cell surface binding pattern of 10 lectins (HPA, SBA, ABA, DSA, PNA, RCA-I, UEA-I, LTA, WGA and ConA) in the serosa of 48 adenocarcinoma specimens. We also investigated the usefulness of six lectins (HPA, SBA, RCA-I, UEA-I, LTA and WGA) in identification of RMC and AC in 16 serous effusions. DSA reactivity was significantly higher (P < 0.05) in static mesothelial cells (SMC) than in RMC. Reactivity for LTA and ConA was significantly lower (P < 0.05) in SMC than in RMC. Anti-CK and anti-VM immunoreactivity was always positive in RMC and almost negative in SMC. In serous effusions, HPA, SBA and UEA-I binding was evident in 100, 88 and 81% of AC, respectively. Little to no binding of HPA, SBA or UEA-I was detected in RMC. Our results suggest that the morphological differences between SMC and RMC are likely to be due to differences in cytoskeletal composition, with accompanying changes in cell-surface lectin-binding patterns. HPA, SBA and UEA-I are likely to be useful markers for identification of RMC and AC in cytology.

Surgical treatment of patients with T2 gallbladder carcinoma invading the subserosal layer

BACKGROUND

Because T2 carcinoma of the gallbladder that invades perimuscular connective tissue without extension beyond serosa or into the liver has a hope for longterm survival, we attempted to clarify significant prognostic factors with respect to tumor- and surgery-related variables.

STUDY DESIGN

Of 65 patients with gallbladder carcinoma who had undergone surgical resection from 1983 to 1999, 28 had T2 carcinoma histologically proved. The significance of variables for survival was examined by the Kaplan-Meier method and log-rank test followed by multivariate analyses using Cox's proportional hazard model.

RESULTS

There were 17 patients with stage II carcinoma (T2 N0 M0), 6 with stage III (T2 N1 M0), and 5 with stage IVB. Lymph node metastasis was present in 11 patients (39%) and it reached to the peripancreatic head region (N2) in 5 of them. Lymphatic, venous, and perineural invasions were found in 68%, 57%, and 43%, respectively. With respect to tumor factors, the absence of perineural invasion (Odds ratio [OR] 16.77, 95% confidence interval [CI] 2.17-129.94, p = 0.0069), absence of lymph node metastasis (OR 15.00, 95% CI 2.08-108.33, p = 0.0073), and stage II (II versus III and IVB, OR 15.00, 95% CI 2.08-108.33, p = 0.0073) were significant factors related to good postoperative survival in the multivariate analysis. Surgical procedure (radical resection versus cholecystectomy, OR 4.31, 95% CI 1.34-13.82, p = 0.0142) and surgical margin (OR 7.41, 95% CI 2.19-25.13, p = 0.0013) were significant factors in the univariate analysis. Cancer-free surgical margins provided a significantly better survival (5-year survival rate, 62%); none with cancer-positive surgical margins survived for more than 27 months. In the multivariate analysis, surgical procedure was significant (OR 25.49, 95% CI 1.62-400.72, p = 0.021). Radical surgery, including extended cholecystectomy (resection of the gallbladder together with the gallbladder bed of the liver) and anatomic resection of liver segment 5 and of the lower part of segment 4, gave a significantly better 5-year survival rate than cholecystectomy (59% versus 17%). The 5-year survival rate after radical resection in patients with stage II was 75%; that in patients with stage III and IVB was 33%.

CONCLUSIONS

Results suggest that radical surgery is the treatment of choice for patients with T2 carcinoma of the gallbladder. The presence of lymph node metastasis, perineural invasion, or both suggests the necessity of additional treatment after radical surgery.

Useful polyclonal antibodies against synthetic peptides corresponding to immunoglobulin light chain constant region for immunohistochemical detection of immunoglobulin light chain amyloidosis

For the immunohistochemical detection of immunoglobulin (Ig) light chain amyloidosis on formalin-fixed, paraffin-embedded tissue sections, we prepared polyclonal antibodies against synthetic peptides corresponding to positions 118-134 of Ig lambda light chain and positions 116-133 of Ig kappa light chain. Nineteen cases of systemic Ig lambda light chain amyloidosis (Alambda amyloidosis), 10 cases of systemic Ig kappa light chain amyloidosis (Akappa amyloidosis), one case of immunohistochemically unclassified systemic amyloidosis and five cases of localized Alambda amyloidosis were tested with these antibodies. Anti-lambda (118-134) antiserum and the affinity-purified antibody both reacted with 18 of the 19 cases of systemic Alambda amyloidosis and all cases of localized Alambda amyloidosis, although the immunoexpression was somewhat variable in intensity in different areas within the same specimen in both systemic and localized amyloidosis. The signal intensities in plasma cells and serum reacted for anti-lambda (118-134) antiserum were weaker than signals obtained with commercially available anti-Ig lambda light chain antibodies. Anti-kappa (116-133) antiserum and the affinity-purified antibody reacted with nine of the 10 cases of systemic Akappa amyloidosis. We conclude that these antibodies against synthetic peptides corresponding to the Ig light chain constant region are useful for the classification of amyloidosis on formalin-fixed, paraffin-embedded tissue sections.

Relationship between effects of phenolic compounds on the generation of free radicals from lactoperoxidase-catalyzed oxidation of NAD(P)H or GSH and their DPPH scavenging ability

The influence of various phenolic compounds on the lactoperoxidase (LPO)/hydrogen peroxide (H2O2)-catalyzed oxidation of biochemical reductants such as reduced beta-nicotinamide adenine dinucleotide (NADH), reduced beta-nicotinamide adenine dinucleotide phosphate (NADPH) or reduced glutathione (GSH) was investigated by electron spin resonance (ESR) spectroscopy. Micromolar quantities of phenolic compounds such as 17beta-estradiol, phenol, and p-chlorophenol enhanced the LPO/H2O2-catalyzed oxidation of NAD(P)H or GSH to generate a large amount of superoxide radical (O2*-) or glutathione thiyl radical (GS*), while, phenolic compounds such as quercetin and Trolox C greatly suppressed the generation of O2*- and GS*. In order to elucidate the effects of phenolic compounds on the generation of O2*- and GS*, their quenching activities for a stable radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH), were investigated by ESR spectroscopy. 17beta-Estradiol, phenol, and p-chlorophenol showed very weak scavenging activities for DPPH, but quercetin and Trolox C showed strong activities. This suggests that the ability of phenolic compounds to enhance LPO/H2O2-catalyzed oxidation of NAD(P)H or GSH relates inversely to their ability to quench DPPH. That is, phenolic compounds having weak quenching activity against DPPH may enhance the LPO/H2O2-catalyzed oxidation of NAD(P)H or GSH to generate a large amount of O2*- or GS*.

Leaf senescence under various gravity conditions: relevance to the dynamics of plant hormones

Effects of simulated microgravity and hypergravity on the senescence of oat leaf segments excised from the primary leaves of 8-d-old green seedlings were studied using a 3-dimensional (D) clinostat as a simulator of weightlessness and a centrifuge, respectively. During the incubation with water under 1-g conditions at 25 degrees C in the dark, the loss of chlorophyll of the segments was found dramatically immediately after leaf excision, and leaf color completely turned to yellow after 3-d to 4-d incubation. In this case kinetin (10 micromolar) was effective in retarding senescence. The application of simulated microgravity conditions on a 3-D clinostat enhanced chlorophyll loss in the presence or absence of kinetin. The loss of chlorophyll was also enhanced by hypergravity conditions (ca. 8 to 16 g), but the effect was smaller than that of simulated microgravity conditions on the clinostat. Jasmonates (JAs) and abscisic acid (ABA) promoted senescence under simulated microgravity conditions on the clinostat as well as under 1-g conditions. After 2-d incubation with water or 5-d incubation with kinetin, the endogenous levels of JAs and ABA of the segments kept under simulated microgravity conditions on the clinostat remained higher than those kept under 1-g conditions. These findings suggest that physiological processes of leaf senescence and the dynamics of endogenous plant hormone levels are substantially affected by gravity.

Growth and development in higher plants under simulated microgravity conditions on a 3-dimensional clinostat

Growth and development of etiolated pea (Pisum sativum L. cv. Alaska) and maize (Zea mays L. cv. Golden Cross Bantam) seedlings grown under simulated microgravity conditions were intensively studied using a 3-dimensional clinostat as a simulator of weightlessness. Epicotyls of etiolated pea seedlings grown on the clinostat were the most oriented toward the direction far from cotyledons. Mesocotyls of etiolated maize seedlings grew at random and coleoptiles curved slightly during clinostat rotation. Clinostat rotation promoted the emergence of the 3rd internodes in etiolated pea seedlings, while it significantly inhibited the growth of the 1st internodes. In maize seedlings, the growth of coleoptiles was little affected by clinostat rotation, but that of mesocotyls was suppressed, and therefore, the emergence of the leaf out of coleoptile was promoted. Clinostat rotation reduced the osmotic concentration in the 1st internodes of pea seedlings, although it has little effect on the 2nd and the 3rd internodes. Clinostat rotation also reduced the osmotic concentrations in both coleoptiles and mesocotyls of maize seedlings. Cell-wall extensibilities of the 1st and the 3rd internodes of pea seedlings grown on the clinostat were significantly lower and higher as compared with those on 1 g conditions, respectively. Cell-wall extensibility of mesocotyls in seedlings grown on the clinostat also decreased. Changes in cell wall properties seem to be well correlated to the growth of each organ in pea and maize seedlings. These results suggest that the growth and development of plants is controlled under gravity on earth, and that the growth responses of higher plants to microgravity conditions are regulated by both cell-wall mechanical properties and osmotic properties of stem cells.