Disseminated Histiocytic Sarcoma in an African Hedgehog (Atelerix albiventris)

Disseminated histiocytic sarcoma (HS) was diagnosed on post-mortem examination of a 1.5-year-old African hedgehog (Atelerix albiventris) that was presented in poor physical condition and with diarrhoea. Leucocytosis and a hypoechoic abdominal mass were noted on haematological and ultrasonographical examinations. Gross pathological, histopathological, immunohistochemical and ultrastructural evaluation of the mass supported a diagnosis of disseminated HS. To our knowledge, this report represents the first documentation of disseminated HS in this species.

Expression of nephrin, podocin, α-actinin-4 and α3-integrin in canine renal glomeruli

The biological features of podocytes that contribute to the pathogenesis of proteinuria have not been investigated in dogs. The aim of this study was to investigate the expression and localization of nephrin, podocin, α-actinin-4 and α3-integrin in canine renal glomeruli. Renal cortical tissue was collected from the kidneys of five normal adult beagles. Western blotting and immunofluorescence microscopy revealed specific expression and localization of the four proteins in canine glomeruli. Expression of genes encoding the four molecules in isolated glomeruli was detected by reverse transcriptase polymerase chain reaction. The results of this study will permit future exploration of podocyte injury and its involvement in protein leakage from the capillary wall in canine glomerular diseases.

Collagenofibrotic Glomerulonephropathy with Fibronectin Deposition in a Dog

We report herein a case of collagenofibrotic glomerulonephropathy in a 3-year-old Shiba Inu with severe proteinuria. Histologically, renal glomeruli were enlarged with massive deposition of a homogeneous eosinophilic substance within the mesangium and capillary walls. The deposits reacted weakly with periodic acid-Schiff, stained deep blue with Masson's trichrome, and were positive by immunofluorescence for type III collagen and fibronectin. Ultrastructurally, the deposits consisted of fibrils and amorphous material in the mesangial matrix and beneath the glomerular capillary endothelium. The fibrils had transverse bands analogous to those of collagen fibrils. Electron microscopy also revealed focal detachment of podocytes and foot process effacement in glomerular tufts, which suggested that podocyte injury had contributed to the development of proteinuria in this dog. The current case resembles collagenofibrotic glomerulonephropathy (CFGN) in humans in histopathologic, immunofluorescence, and electron microscopic findings. This is the first report of CFGN in a nonhuman species with glomerular deposition of fibronectin and type III collagen.

Expression of cyclooxygenase-2, P-glycoprotein and multi-drug resistance-associated protein in canine transitional cell carcinoma

Cyclooxygenase-2 (COX-2), P-glycoprotein (P-gp) and multi-drug resistance-associated protein (MRP) are considered important tumor-associated proteins in humans and dogs. In the present study, we immunohistochemically evaluated the expression of these proteins in canine patients with transitional cell carcinoma (TCC). Of 52 cases, 30 (57.7%) were positive for COX-2, 40 (76.9%) for P-gp, and only 10 (19.2%) for MRP. In addition, 27 samples (27/52, 51.9%) were positive for two markers, while 3 (5.7%) and 5 (9.6%) cases were positive and negative, respectively, for all three markers. No significant correlations were seen for COX-2 and P-gp on Fisher's exact test and Mann-Whitney's test, but a significance was seen on Spearman's rank correlation analysis using the IHC scoring system (P=0.043). These results suggest that P-gp expression is induced by overexpression of COX-2 in canine patients with TCC.

Cloning and expression of the ecdysteroid receptor during ecdysis and reproduction in females of the soft tick, Ornithodoros moubata (Acari: Argasidae)

Molecular mechanisms of ecdysteroid regulation in development and reproduction have been thoroughly investigated in Diptera and Lepidoptera, but few studies report the molecular actions of ecdysteroids in hemimetabolous insects and more primitive arthropods. Ecdysteroids appear to be the main hormones regulating development and vitellogenesis in ticks. An ecdysteroid receptor that showed high homology with EcRs of other arthropods was isolated from Ornithodoros moubata (OmEcRA). OmEcR expression patterns coincided with ecdysteroid titres in the haemolymph during moulting and vitellogenesis and differed between mated and virgin females. Therefore, OmEcR appears to mediate the regulation of moulting and vitellogenesis by ecdysteroids in O. moubata females as seen in other arthropods.

Spontaneous extraskeletal osteosarcomas of the subcutis in Djungarian hamsters (Phodopus sungorus): report of two cases

Spontaneous subcutaneous extraskeletal osteosarcoma was diagnosed in the subcutaneous tissue of two Djungarian hamsters. Histologically, the tumour was characterized by multiple nests of osseous and cartilaginous components within a proliferation of pleomorphic cells. No abnormality was observed in any skeletal bones and no change suggesting tumorous growth was observed in any other sites. This is the first report of extraskeletal osteosarcomas in Djungarian hamsters.

Relation between clenching strength and occlusal force distribution in primary dentition

The aim of this study was to investigate the relation between clenching strength and occlusal force distribution in primary dentition. Twenty healthy children with normal occlusions: 11 boys and 9 girls, ages 3.2-5.8 years (avg. 4.5 years) were selected. Setting the bilateral masseter muscular activity at maximum clenching in full intercuspation as 100%, the occluding forces at 20, 40, 60, 80 and 100% clenching were recorded with pressure-sensitive sheets (Dental Prescale 50H, type R, Fuji Photo Film Co.), and the force of each primary tooth was analysed by computer (Occluzer FPD703). Occlusal force distribution was expressed as a percentage of the total occlusal force of each tooth and was compared between each clenching. There were no significant differences between various clenching strengths in the occlusal force distribution in primary dentition [one-way repeated-measures analysis of variance (ANOVA)]. Thus, the results of the present study suggest that the distribution of occluding forces on a primary dental arch had its own pattern and that the clenching strength had no effect on that pattern. These patterns may be useful in determining occlusal function in children.

Oxyhemoglobin produces necrosis in cultured smooth muscle cells

OBJECT

Myonecrosis in the tunica media, which is defined morphologically, is one of the most striking alterations in the cerebral arterial wall following subarachnoid hemorrhage (SAH). In this study, oxyhemoglobin (OxyHb) was added to cultured rat aortic smooth muscle cells to determine the pattern of cell death by morphological and biochemical techniques.

METHODS

Confluent rat aortic smooth muscle cells were treated with OxyHb in a concentration- and time-dependent manner. Cell density was assayed by counting the number of cells that attached to the culture dishes after exposed to OxyHb. To identify cell death pattern, DNA analysis, electron microscopy, and Western blotting using poly (ADP-ribose) polymerase (PARP) antibody were performed.

CONCLUSIONS

OxyHb decreased cell density in a concentration- and time-dependent manner. DNA analysis showed a smear pattern characteristic of cell necrosis. Transmission electron microscopy demonstrated disintegration of cell membrane and destruction of cell organelles. No apoptotic changes, such as condensation of chromatin or apoptotic bodies were observed. Western blotting using PARP antibody revealed that 116 kDa PARP was not cleaved to 85 kDa, an apoptosis-related fragment. These results demonstrated morphologically and biochemically that OxyHb induced necrosis, not apoptosis, in cultured smooth muscle cells.

Mitogen-activated protein kinase plays an important role in hemolysate-induced contraction in rabbit basilar artery

OBJECT

Mitogen-activated protein kinase (MAPK) is an important signaling factor in the vascular proliferation and contraction, the two features of cerebral vasospasm following subarachnoid hemorrhage. We studied the possible involvement of MAPK in hemolysate-induced signal transduction and contraction in rabbit basilar artery.

METHODS

Isometric tension was used to record the contractile response of rabbit basilar artery to hemolysate. Western blots using antibodies for MAPK were conducted. 1) Hemolysate produced a concentration-dependent contraction of rabbit basilar artery. Pre-incubation of arteries with MAPK kinase inhibitor PD-98059 markedly reduced the contraction induced by hemolysate. PD-98059 also relaxed, in a concentration-dependent fashion, the sustained contraction induced by hemolysate (10%). 2) Hemolysate produced a time-dependent elevation of MAPK immunoreactivity in Western blot in rabbit basilar artery. MAPK was enhanced 3 min after hemolysate exposure and the effect reached maximum at 5 min. The immunoreactivity of MAPK decayed slowly with time, but the level of MAPK was still higher than the basal level even at two hours after exposure to hemolysate. 3) Pre-incubation of arteries with MAPK kinase inhibitor PD-98059 abolished the effect of hemolysate on MAPK immunoreactivity.

CONCLUSION

Hemolysate produced contraction of rabbit basilar artery possibly by activation of MAPK. MAPK inhibitors may be useful in the treatment of cerebral vasospasm.

Role of tyrosine kinase in fibroblast compaction and cerebral vasospasm

Hemolysate, a proposed causative agent for cerebral vasospasm following subarachnoid hemorrhage, produces contraction of cerebral arteries by activation of tyrosine kinases. In addition, hemolysate accelerates fibroblast collagen compaction that could play a role in cerebral vasospasm. We studied the effect of hemolysate on tyrosine phosphorylation and fibroblast collagen compaction in cultured dog cerebral and human dermal fibroblasts using tyrosine kinase inhibitors and tyrosine antibodies (Western blot). 1) Hemolysate was found to enhance tyrosine phosphorylation of two proteins approximately 64 and 120 kDa. The effect of hemolysate was time- and concentration-dependent. 2) Two main components in hemolysate, oxyhemoglobin and adenosine triphosphate (ATP), produced similar results to that of hemolysate. 3) Tyrosine kinase inhibitor genistein and tyrphostin A51 (30 microM) markedly reduced the effect of hemolysate on tyrosine phosphorylation. 4) In another study, hemolysate increased fibroblast collagen compaction and the effect of hemolysate was reduced by genistein and tyrphostin A51. We conclude that hemolysate activates tyrosine kinase that may lead to acceleration of fibroblast compaction. This effect of hemolysate may contribute to cerebral vasospasm.

Oxyhemoglobin produces apoptosis and necrosis in cultured smooth muscle cells

Confluent rat aortic smooth muscle cells were treated with OxyHb in a concentration- and time-dependent manner. A high concentration of OxyHb (100 microM) within 24 h decreased cell density. DNA analysis showed a smear pattern characteristic of cell necrosis. Transmission electron microscopy demonstrated disintegration of the cell membrane and destruction of cell organelles. Western blotting using PARP antibody revealed that 116 kDa PARP was not cleaved to 85 kDa, an apoptosis-related fragment. On the contrary, a low concentration of OxyHb (10 microM) produced apoptotic cell death at 72 h that was supported by DNA analysis and TUNEL staining. These results demonstrated that a high level of OxyHb induced necrosis within 24 h and a low concentration of OxyHb produced apoptosis after 72 h in cultured smooth muscle cells. Morphological alterations induced by OxyHb might contribute to the vascular wall changes in the cerebral arteries following subarachnoid hemorrhage (SAH).

Microvasculature of hydronephrotic kidneys in KK-A(Y) mice

Spontaneous hydronephrosis in KK-A(Y) mice was studied using light and electron microscopy and scanning electron microscopy of resin casts to evaluate micro vascular changes in the kidney. The renal parenchyma was extremely thin as a result of tubular atrophy. Histologically, varying degrees of glomerulosclerosis were observed. Ultrastructurally, marked thickenings of the glomerular basal lamina, an increase in mesangial cells and matrix, and marked effacement of foot processes were observed. In resin casts, a marked reduction in number of glomeruli was evident. The capillaries were thin, strangulated and tom-off to varying degrees in severely affected glomeruli. In the medulla, the three-dimensional capillary network running along the tubules was lost and changed to a two-dimensional vascular bed. Despite severe hydronephrosis, the glomerular capillary network was relatively well preserved, being either slightly or moderately injured in approximately 60% of surviving glomeruli.

Effect of endothelin receptor antagonists on non-muscle matrix compaction in a cell culture vasospasm model

Endothelin-1 (ET-1), a potent vascular smooth muscle constrictor, is one of the possible spasmogens in cerebral vasospasm. However, the role of ET-1 in non-muscle compaction (another aspect of the pathogenesis of cerebral vasospasm) has not been reported. This study was undertaken to demonstrate the effect of ET-1, as well as erythrocyte lysate and bloody cerebrospinal fluid (CSF), on fibroblast populated collagen lattice (FPCL) compaction. Human dermal fibroblasts were used to form FPCL. The concentration-dependent effect of ET-1 was examined in the absence and presence of an ETA receptor antagonist (BQ-485), or an ETB receptor antagonist (BQ-788), or both. FPCL compaction was determined by measuring reduction of areas over five days following treatment. To compare the effect of ET-1 on lattice compaction, erythrocyte lysate and bloody CSF obtained from a cerebral vasospasm patient were also tested. We found that ET-1 increased FPCL compaction in a concentration-dependent (but not time-dependent) manner. Erythrocyte lysate produced the strongest compaction, however, without time-dependence. Bloody CSF promoted FPCL compaction in a time-dependent fashion. Compaction induced by ET-1 was inhibited by BQ-485 but not by BQ-788. We concluded that ET-1 promotes FPCL compaction by activation of ETA receptors. Other components in bloody CSF or erythrocytes may also contribute to FPCL compaction.

Apoptosis of endothelial cells in vessels affected by cerebral vasospasm

BACKGROUND

Cerebral vasospasm after subarachnoid hemorrhage is a prolonged contraction that leads to cerebral ischemia or infarction. Morphological studies of cerebral arteries during vasospasm have shown extensive necrosis of smooth-muscle cells and desquamation and dystrophy of endothelial cells. The mechanism of cellular death is unknown.

METHODS

We report an observation of apoptotic changes in the cerebral arteries of a patient who died after suffering severe cerebral vasospasm caused by aneurysmal rupture. Subarachnoid hemorrhage and cerebral vasospasm were confirmed by computed tomography scanning and angiogram. Histological and immunohistological examinations for apoptosis were performed in cerebral arteries. For control, the arteries from another patient, who died of trauma without head injury, were used.

RESULTS

Corrugation of the internal elastic lamina and increased amounts of connective tissue was demonstrated by light microscopy. Apoptotic changes, characterized by condensation of chromatin of the nucleus and detachment from the basal membrane, were found on transmission electron microscopy in endothelial cells. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling reaction revealed positive staining of the nuclei of the endothelial cells.

CONCLUSIONS

This study demonstrates that apoptosis occurred in the cerebral arteries in a patient who died of cerebral vasospasm. The possible role of apoptosis in cerebral vasospasm is discussed.

Hemolysate induces tyrosine phosphorylation and collagen-lattice compaction in cultured fibroblasts

Hemolysate, a proposed causative agent for cerebral vasospasm after subarachnoid hemorrhage, produces contraction of cerebral arteries by activation of tyrosine kinases. In addition, hemolysate increases fibroblast-collagen compaction that could play a role in cerebral vasospasm. We studied the effect of hemolysate on tyrosine phosphorylation and fibroblast-collagen compaction in cultured canine basilar and human dermal fibroblasts using tyrosine kinase inhibitors and tyrosine antibodies. Hemolysate enhanced tyrosine phosphorylation of two proteins, 64 and 120 kDa, in cultured canine basilar artery and human dermal fibroblast cells. The effect of hemolysate was time-dependent and concentration-dependent. Oxyhemoglobin and ATP, the two major components of hemolysate, produced similar tyrosine phosphorylation, however, with a different time course. Tyrosine kinase inhibitors genistein and tyrphostin A51 abolished the effect of hemolysate in both cerebral and dermal fibroblasts. Hemolysate increased fibroblast-populated collagen-lattice compaction and tyrosine kinase inhibitors genistein and tyrphostin A51 attenuated the effect of hemolysate. We conclude that hemolysate activates tyrosine kinase that leads to the increase of fibroblast compaction. This effect of hemolysate may contribute to cerebral vasospasm.

Overexpression and genetic abnormality of p53 in parathyroid adenomas

To study the significance of p53 abnormality in parathyroid tumors, 32 parathyroid adenomas and 22 hyperplastic glands from 14 cases of secondary hyperparathyroidism were analysed using immunohistochemistry, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), single-strand conformation polymorphism (SSCP) and DNA sequencing. Immunohistochemical study revealed p53 overexpression in four parathyroid adenomas, of which two showed diffuse and one showed focal nuclear pleomorphism. Genetic analysis disclosed allelic loss in one, and a point mutation (R290H) and a polymorphism (L257 L) in another of the two other adenomas with diffuse nuclear pleomorphism. No abnormalities were discovered in the other two adenomas, although one had a R72P polymorphism in exon 4. There was no evidence of malignancy of the four tumors in either clinical or pathological terms. None of the 22 hyperplastic glands showed p53 overexpression. These results demonstrate that p53 abnormality can occur in benign parathyroid adenomas and is more prevalent in those with nuclear pleomorphism than in those without.

Oxyhemoglobin-induced apoptosis in cultured endothelial cells

OBJECT

Oxyhemoglobin (OxyHb) is one of the most important spasmogens for cerebral vasospasm that follows aneurysmal subarachnoid hemorrhage. The cytotoxic effect of OxyHb has been documented in endothelial and smooth-muscle cells; however, the pattern of cell death--necrosis or apoptosis--as the final stage of cell damage has not been demonstrated. This study was undertaken to determine if OxyHb induces apoptotic changes in cultured bovine aortic endothelial cells.

METHODS

Confluent bovine aortic endothelial cells were treated with OxyHb in a concentration- and time-dependent manner. Cell density was assayed by counting the number of cells that attached to culture dishes after exposure to OxyHb. To identify apoptotic changes, the investigators used three specific methods: DNA fragmentation (electrophoreses), the apoptotic body (transmission electron microscopy), and cleavage of poly (adenosine diphosphate ribose) polymerase (PARP [Western blotting]).

CONCLUSIONS

Oxyhemoglobin decreased cell density in a concentration- and time-dependent manner. Analysis of DNA showed a pattern of internucleosomal cleavage characteristic of apoptosis (DNA ladder). Transmission electron microscopy demonstrated condensation of nuclei and apoptotic bodies in OxyHb-treated endothelial cells. Western blotting with the PARP antibody revealed that the 116-kD PARP was cleaved to the 85-kD apoptosis-related fragment. These results for the first time demonstrated that the OxyHb induces apoptosis in cultured endothelial cells.

Bloody cerebrospinal fluid alters contractility of cultured arteries

The pathogenesis of cerebral vasospasm that follows aneurysmal subarachnoid hemorrhage (SAH) is poorly understood. Multiple methods have been used to clarify the mechanism of spasmogen-induced vasospasm, however, each method has its own limitations. Cultured cells lose their phenotype and inter-cellular interactions, and animal models are expensive and can be used only in some established centers. Isolated cerebral arteries have been used extensively to study the contractility by transient exposure to spasmogens that, however, can hardly represent cerebral vasospasm that occurs 2-4 days after SAH. In this study, we cultured arteries with bloody cerebrospinal fluid (CSF) from patients of cerebral vasospasm and studied the contractility of the arteries 1, 3 and 4 days later. This method preserves artery wall structure, prolongs exposure of artery to bloody CSF, and is simple and inexpensive. Cultured rat aorta showed enhanced contractile response to 5-HT (p < 0.001) but reduced response to KCl (p < 0.05) 4 days after culturing with bloody CSF. We concluded that the contractility of arteries was modified by prolonged incubation with bloody CSF. Our observations in this study could be important and may explain some aspects of pathogenesis of cerebral vasospasm.

Mitogen-activated protein kinase mediation of hemolysate-induced contraction in rabbit basilar artery

OBJECT

Mitogen-activated protein kinase (MAPK) is an important signaling factor in vascular proliferation and contraction, which are the two features of cerebral vasospasm that follow subarachnoid hemorrhage. The authors studied the possible involvement of MAPK in hemolysate-induced signal transduction and contraction in rabbit basilar artery (BA).

METHODS

Isometric tension was used to record the contractile response of rabbit BA to hemolysate, and Western blots were obtained using antibodies for MAPK. The following results are reported. 1) Hemolysate produced a concentration-dependent contraction of rabbit BA; however, preincubation of arteries with the MAPK kinase (MEK) inhibitor PD-98059 markedly reduced this contraction. The administration of PD-98059 also relaxed, in a concentration-dependent fashion, the sustained contraction induced by 10% hemolysate. 2) The Janus tyrosine kinase 2 inhibitor AG-490, preincubated with arterial rings, reduced the contractile response to hemolysate but failed to relax the sustained contraction induced by this agent. The Src-tyrosine kinase inhibitor damnacanthal and the phosphatidylinositol 3-kinase inhibitor wortmannin failed to reduce hemolysate-induced contraction. 3) Hemolysate produced a time-dependent elevation of MAPK immunoreactivity as seen on Western blots of rabbit BA. The MAPK was enhanced 1 minute after hemolysate exposure and the effect reached maximum levels at 5 minutes. The immunoreactivity of MAPK decayed slowly over time, but the level of this kinase was still higher than the basal level, even at 2 hours after exposure to hemolysate. Preincubation of arteries with the MEK inhibitor PD-98059 abolished the effect of hemolysate on MAPK immunoreactivity.

CONCLUSIONS

Hemolysate produced contraction of rabbit BA, possibly by activation of MAPK, and therefore MAPK inhibitors may be useful in the treatment of cerebral vasospasm.

"Kissing" bilateral large carotid-ophthalmic aneurysms. A case report

A case of unruptured bilateral large carotid-ophthalmic aneurysms, which appear to be adjoining and "kissing" each other when visualized by three-dimensional computed tomographic angiography (3-D CTA), is reported. Although bilateral carotid-ophthalmic aneurysms are not rare, bilateral large ones are quite rare, and direct imaging of "kissing aneurysms" of this portion has not been reported. Since 3-D CTA is becoming a useful tool for the diagnosis of cerebral aneurysms, we propose that these and similar bilateral large carotid-ophthalmic aneurysms are good candidates for the term "kissing aneurysms".

Treatment of a Brodie bite by lower lateral expansion: a case report and fourth year follow-up

The patient was a 4 year 4 month old boy at the first visit. The chief complaint was chewing dysfunction. The intra-oral and facial films, study casts, cephalometrics, muscle-balance monitor, temporomandibular joint radiographs were analyzed. The patient presented with a Brodie bite or unilateral posterior cross bite. The upper dental arch was wider than other children of his age. The lower dental arch was significantly smaller than the upper dental arch. The lower dental arch was expanded using a Schwarz appliance. The period of treatment was one year and two months. The period of observation was four years and ten months. First the patient underwent chewing training and secondarily then was treated by lateral expansion. After this treatment the patient achieved good occlusion and muscle function, while the morphology and function of the temporomandibular joints were improved, as well.

Molecular structure of canine LINE-1 elements in canine transmissible venereal tumor

We determined the 4251-bp sequence of open reading frame 2 (ORF2) of canine LINE-1 retroposon that encodes 1275 amino acids. The truncated LINE-1 inserts associated with transmissible venereal tumor (TVT) of dogs contained the 1378-bp LINE-1 insert (TVT-LINE) flanked by 10-bp direct repeats upstream to c-myc gene. The TVT-LINE elements were composed of 416 bp inverse sequences homologous to the complementary strand of the LINE-1, a 5-bp deletion and 962-bp sequences homologous to the 3' region of the LINE-1.

Obstructive uropathy and hydronephrosis in male KK-Ay mice: a report of cases

Uropathy associated with hydronephrosis was observed frequently in our male KK-Ay mouse colony during a long-term study of diabetes. The lesion occurred in 24 of the 31 KK-Ay male mice and accounted for the greatest number of spontaneous deaths among them. It was observed after 4 months of age and involved about hard plugs of altered seminal material resembling the seminal vesicle secretion. The plugs became impacted in the urethral bulb and the bladder. The penile anatomy, with its flexure, pressure on the urethra from the bulbocavernosus muscle, and the characteristic ability of the seminal fluid to easily coagulate to form the vaginal plug may have contributed to the lesion. Correlation between development of the uropathy and diabetes has not been established.

Collagen fiber arrangement in canine hepatic venules

Cell-maceration/scanning electron microscopy, serial sections and scanning electron microscopy of vascular resin casts were employed to demonstrate the arrangement of collagen fibers in the terminal hepatic venules, involving the central, intercalated and collecting veins in dog liver. In cell-maceration specimens, each collagen fiber was observed to run in various directions, forming a sheath with a compact meshwork of collagen fibers. The collagenous meshwork in the hepatic venules was looser than those of the terminal portal venules and hepatic arterioles. Some collagen fibers formed bundles with an elongated spiral arrangement encircling the wall of the terminal hepatic venules. In resin casts, these venules were observed as a twisted configuration caused by spiral collagen bundles. A helical modification of such connective tissue bundles might provide a mechanically stable vascular structure and permit reversible changes in linear and circumferential vascular dimensions at the terminal tributaries of veins. Round or oval pores with diameters of approximately 9 microns were also observed in the sheath of collagen fibers. These pores, together with the relatively loose collagenous meshwork in the hepatic venules, might play a role in lymphocyte migration from these venules into the surrounding tissue and provide high permeability to the venule walls. No such helical configuration and pores were observed in either the portal venules or the hepatic arterioles.

Glomerular vascular changes in KK-Ay mice with early diabetes: scanning electron microscopy of vascular resin casts

Vascular changes, the angioarchitecture of renal glomerular fine vessels in early diabetic KK-Ay mice of 4 months of age were examined by scanning electron microscopy of corrosion casts. Histologically, enlargement of glomeruli and dilation of glomerular capillaries were found. In resin cast specimens, glomeruli with diabetes were larger than normal, and an increase in diameter of the glomerular vessels was found in diabetic mice. No capillary proliferation, distortion of glomerular vessels and destruction of glomerular capillary loops were found in diabetic mice. The increased vascular diameter may explain the increase in blood flow in the glomeruli, affecting kidney function in early diabetes.

Three-dimensional analysis of vasospastic major cerebral arteries in rats with the corrosion cast technique

BACKGROUND AND PURPOSE

Although mice, rats, and other small animals are commonly used for molecular biology research, their use in the evaluation of cerebral vasospasm after subarachnoid hemorrhage is somewhat problematic because of the correspondingly small size of their cerebral vessels. We have already reported that the corrosion cast technique was useful for evaluating newly formed cerebral vessels in neural grafts in these small animals. In the present study we applied the corrosion cast technique to the evaluation of hemolysate-induced cerebral vasospasm in rats and performed three-dimensional analysis for comparison. The casting was done 10 minutes after the hemolysate injection, so that only acute "vasospasm" was assessed.

METHODS

After withdrawal of 0.1 mL cerebrospinal fluid, 0.2 mL hemolysate (n = 9) or saline (n = 10) was injected into the cisterna magna of male Sprague-Dawley rats weighing between 300 and 350 g. Ten minutes later, perfusion of a semipolymerized casting medium was performed at an injection pressure of 100 to 120 mm Hg. The brains were immersed and corroded in 10% NaOH solution. After these procedures, the basilar artery as well as peripheral vessels was analyzed morphologically with scanning electron microscopy. Conventional histological analysis with the use of paraffin-embedded section with hematoxylin-eosin staining was also performed, and the results were compared with those for the corrosion cast methods.

RESULTS

In the saline-injected group, SEM showed that the inner surface of the basilar artery was smooth and the form of the endothelial cell was printed on the surface of the cast. In the hemolysate-injected group, the basilar artery showed an apparent vasospasm over its entire length, and corrugation was observed on the inner surface of the basilar artery in a three-dimensional fashion. Higher magnification revealed that the nuclei of the endothelial cells were distorted. Local narrowing of the basilar artery and vasospasm in the arteries of the anterior circulation and in peripheral arteries were also observed. Measurement of the inner diameter of the basilar artery showed 37.8% contraction in the hemolysate-injected group compared with the saline-injected group by the corrosion cast method. This degree of vasospasm was similar to that observed by the conventional histological method.

CONCLUSIONS

In this report we show that detailed three-dimensional observation in the rat can be performed qualitatively and quantitatively with the corrosion cast technique. We conclude that this method derives an accurate measurement of the diameter of rat major cerebral arteries and is more reliable for analyzing vasospasm in rats than angiography and other conventional procedures.

Role of extracellular matrix in experimental vasospasm. Inhibitory effect of antisense oligonucleotide on collagen induction

BACKGROUND AND PURPOSE

Although it has been suggested that collagen plays a role in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage, there has been no constructive research to prove it directly. In this study we stopped the transcription of the procollagen type I gene by introducing antisense oligonucleotides for its mRNA in a rat femoral artery model of vasospasm induced by blood and assayed the changes in the vasoconstrictive activity of the vessel and expression of the procollagen mRNA.

METHODS

We applied antisense, sense, or missense oligonucleotides, located at the carboxyl propeptide region for alpha 1(I) procollagen mRNA, onto the femoral artery in a rat femoral artery model of vasospasm. The diameter of the artery was measured by angiography. The transcription level of the procollagen gene in the arterial tissue was assayed by use of reverse transcription-polymerase chain reaction. Morphological change in the artery was observed with aldehyde-fuchsin-Masson-Goldner staining.

RESULTS

In the model, when the artery was exposed to antisense oligonucleotides in pluronic gel for 5 days to prevent arterial contraction, the contraction was inhibited at a significant level (76.0% +/- 5.6) when compared with that in control experiments using sense oligonucleotides (64.0% +/- 2.4), missense oligonucleotides (63.5% +/- 3.5), or gel alone (62.1% +/- 5.8). The application of antisense oligonucleotide resulted in a marked decrease in alpha 1(I) procollagen mRNA expression as determined by polymerase chain reaction, indicating that the collagen reduction by antisense oligonucleotides occurred at the transcription level. Histological staining suggested that collagen accumulation at the site in the artery where antisense oligonucleotide had been administered was indeed less than that in the control artery.

CONCLUSIONS

The results indicate that the induction of procollagen type 1 could cause pathogenesis of the arterial contraction induced by blood in a rat femoral vasospasm model.

Inhibition of vascular contraction by intracisternal administration of preproendothelin-1 mRNA antisense oligoDNA in a rat experimental vasospasm model

To clarify the role of endothelin-1 (ET-1) in the etiology of hemolysate-induced contraction of vessels, the authors introduced antisense oligoDNA for preproendothelin-1 (ppET-1) messenger RNA in a rat model of vasospasm. Phosphorothioate antisense oligoDNAs for ppET-1 were injected into the cisterna magna. Fluorescein isothiocyanate-labeled phosphorothioate antisense oligoDNAs were proven by fluorescence chasing to be incorporated into the vascular wall. Striking inhibitory effects of experimental vasospasm were observed in the basilar artery (BA) in which the oligoDNAs were injected. The vascular contraction was significantly inhibited by oligoDNAs after 20 minutes of hemolysate exposure, which suggested that ET synthesis started approximately 20 minutes after hemolysate stimulation. Expression of ppET-1 in the BA in which the spasm was inhibited was markedly suppressed at the transcription level. The results indicate that ET-1 may play an important role in hemolysate-induced vasoconstriction in rats. In addition, the antisense approach in the cerebrospinal fluid might be a useful tool for preventing cerebral vasospasm.

Vascular architecture of 3-methyl choranthrene-induced rat fibrosarcoma demonstrated by scanning electron microscopy of resin casts

A detailed knowledge of the vascular system of tumors is requisite to a clear understanding of tumor physiology and pathology. Accordingly, in this study, examination was made of the vascular architecture of rat fibrosarcomas induced by 3-methyl choranthrene by scanning electron microscopy of resin casts to observe the three-dimensional vascular pattern of the sarcoma. The results were compared with those of corresponding serial sections of India ink-injected tissue. The major arteries in and around tumors appeared devoid of intra-arterial cushions which regulate blood flow. The arterial lining of resin casts was smooth just at the site where it entered the tumor. This may possibly be indication of degeneration and loss of the smooth muscle layer in the vascular wall. Casts of capillaries were very thin from 4 to 6 microns in diameter and very few sprouts could be seen. Capillaries, frequently present in superficial regions of the tumor, formed a rich irregular fine polygonal network. In fibrous tissue in deeper regions of the tumor, this network was coarse. The absence of intra-arterial cushions and degeneration of muscle cells may thus possibly be the reason for the characteristic haemodynamics of tumors.

[Flavonoid constituents of Melicope triphylla MERR.II]

From the leaves of Melicope triphylla MERR., three new flavonoids (1-3) were isolated, together with nine known flavonoids, 4',5-dihydroxy-3,3',7- trimethoxyflavone (4), 5-hydroxy-3,3',4',7-tetramethoxyflavone (5), 3,3',4',5,7-pentamethoxyflavone (6), 7-hydroxy-3,3',4',5,8-pentamethoxyflavone (7), 3,3',4',5,7,8-hexamethoxyflavone (8), 5-hydroxy-3,7,8-trimethoxy-3',4'-methylenedioxyflavone (9), 7-hydroxy-3,5,8- trimethoxy-3',4'-methylenedioxyflavone (10), 3,5,7,8-tetramethoxy-3',4'-methylenedioxyflavone (11), and 5-hydroxy- 3,6,7,8-tetramethoxy-3',4'-methylenedioxyflavone (12). The structures of 1, 2, and 3 were established as 5-hydroxy-3,7-dimethoxy-3',4'-methylenedioxyflavone, 5-hydroxy-7-isopentenyloxy-3,8-dimethoxy-3',4'-methylenedioxyfl avone, and 4'-hydroxy-7-isopentenyloxy-3,3',5,8-tetramethoxyflavone by their respective chemical and spectral data. The 20 flavonoids isolated from this plant were examined for the piscicidal activities.

The organ distribution of tin and the effect of tin on concentrations of several essential elements in rabbit

The organ distribution and the effects of administration of tin, 5 mumol/kg/day, for 6 days on calcium, copper, iron, magnesium, phosphate, and zinc concentrations in plasma, erythrocytes, liver, kidney, and spleen of adult rabbits were studied. Kidney contained the highest concentration of tin, 15.0 +/- 1.64 micrograms/g wet weight (mean +/- S.D., n = 4). The concentrations of copper, phosphate, and magnesium increased significantly in the kidney, while magnesium concentration decreased in erythrocytes 1 day after the administration of tin for 6 consecutive days. A high correlation coefficient between magnesium and phosphate was observed in all organs tested. The correlation coefficients between P vs. Cu, P vs. Ca, and Mg vs. Ca in the liver were lowered during the period of tin administration, whereas those between P vs. Zn, Mg vs. Zn, and Cu vs. Zn in the kidney disappeared after tin administration was completed.