[Clinical features and gene mutations of 6 patients with carnitine palmitoyltransferase 1A deficiency]

The clinical and biochemical data and gene sequencing results of patients with carnitine palmitoyltransferase 1A deficiency were analyzed, in order to improve the understanding of the disease. Six patients (5 males and 1 female, aged from 1 to 8 years old) with carnitine palmitoyltransferase 1A deficiency from Department of Pediatric Endocrinology and Genetic Metabolism, Xinhua Hospital between 2008 and 2019 were included. Two cases were detected by neonatal screening and had no clinical symptoms. The remaining 4 cases all showed seizures induced by fever, vomiting or diarrhea. All the 6 patients showed increased serum free carnitine (C0), decreased hexadecanoylcarnitine (C16) and octadecanoylcarnitine (C18), and increased C0/(C16+C18). Meanwhile, compound heterozygous mutations of CPT1A gene were detected in all 6 patients, of which 2 were reported mutations (c.281+1G>A and c.968-8C>T), and 10 were new mutations. The new mutations included 6 missense mutations, 1 nonsense mutation, 1 deletion mutation and 2 splicing mutations. Detection of free carnitine and acyl carnitine by tandem mass spectrometry is helpful for early screening and diagnosis of carnitine palmitoyltransferase 1A deficiency.

Plasma metabolite changes in dairy cows during parturition identified using untargeted metabolomics

The metabolic responses of cows undergo substantial changes during the transition from late pregnancy to early lactation. However, the molecular mechanisms associated with these changes in physiological metabolism have not been clearly elucidated. The objective of this study was to investigate metabolic changes in transition cows from the perspective of plasma metabolites. Plasma samples collected from 24 multiparous dairy cows on approximately d 21 prepartum and immediately postpartum were analyzed using ultra-high-performance liquid chromatography/time-of-flight mass spectrometry in positive and negative ion modes. In conjunction with multidimensional statistical methods (principal component analysis and orthogonal partial least squares discriminant analysis), differences in plasma metabolites were identified using the t-test and fold change analysis. Sixty-seven differential metabolites were identified consisting of AA, lipids, saccharides, and nucleotides. The levels of 32 plasma metabolites were significantly higher and those of 35 metabolites significantly lower after parturition than on d 21 prepartum. Pathway analysis indicated that the metabolites that increased from late pregnancy to early lactation were primarily involved in lipid metabolism and energy metabolism, whereas decreased metabolites were related to AA metabolism.

[Prospective cohort study on the risks of pre-pregnancy overweight, excessive gestational weight gain on macrosomia]

Objective: To investigate the risks of pre-pregnancy overweight, excessive gestational weight gain on macrosomia. Methods: We conducted one hospital-based cohort study, focusing on pregnant women from January 2015. All pregnant women attending to this hospital for maternal check-ups, were included in our cohort and followed to the time of delivery. Data related to general demographic characteristics, pregnancy and health status of those pregnant women, was collected and maternal pre-pregnant BMI and maternal weight gain were calculated. Logistic regression was used to explore the risk difference of pre-pregnancy BMI, excessive gestational weight gain on macrosomia. Results: The overall incidence of macrosomia in our cohort appeared as 6.6% (149/2 243). After adjusting the confounding factors including age and histories on pregnancy, pre-pregnancy overweight/obesity was associated with higher risks of macrosomia (OR=3.12, 95%CI: 1.35-7.22, P=0.008; OR=2.99, 95%CI: 1.17-7.63, P=0.022) when comparing to those with normal pre-pregnancy weight. Cesarean delivery and sex of the offspring were associated with higher risk of macrosomia, while excessive gestational weight gain showed no significant difference (OR=1.41, 95%CI: 0.96-2.09, P=0.084). Our data showed that Macrosomia was statistically associated with gestational weight gain (P=0.002). After controlling parameters as age, history of pregnancy and related complications of the pregnant women, results from the logistic regression showed that women with gestational inadequate weight gain having reduced risks to deliver macrosomia, when compared to those pregnant women with adequate weight gain (OR=0.52, 95%CI: 0.30-0.90, P=0.019). Conclusion: Pre-pregnancy overweight and obesity were on higher risks to macrosomia.

Effect of the Fusarium toxins, zearalenone and deoxynivalenol, on the mouse brain

The aim of this study was to find effects of Fusarium toxins on brain injury in mice. We evaluated the individual and combined effect of the Fusarium toxins zearalenone and deoxynivalenol on the mouse brain. We examined brain weight, protein, antioxidant indicators, and apoptosis. After 3 and 5days of treatment, increased levels of nitric oxide, total nitric oxide synthase, hydroxyl radical scavenging, and malondialdehyde were observed in the treatment groups. This was accompanied by reduced levels of brain protein, superoxide dismutase (apart from the low-dose zearalenone groups), glutathione, glutathione peroxidase activity, and percentage of apoptotic cells. By day 12, most of these indicators had returned to control group levels. The effects of zearalenone and deoxynivalenol were dose-dependent, and were synergistic in combination. Our results suggest that brain function is affected by zearalenone and deoxynivalenol.

The Fusarium toxin zearalenone and deoxynivalenol affect murine splenic antioxidant functions, interferon levels, and T-cell subsets

This study aimed to evaluate the effects of the Fusarium toxin zearalenone (ZEA) and deoxynivalenol (DON) on splenic antioxidant functions, IFN levels, and T-cell subsets in mice. Herein, 360 mice were assigned to nine groups for a 12-day study. Mice were administered an intraperitoneal injection for 4 consecutive days with different concentrations of ZEA alone, DON alone, or ZEA+DON. Spleen and blood samples were collected on days 0, 3, 5, 8, and 12. Mice in each of the experimental groups showed dysreglated splenic antioxidant functions, IFN levels, and T-cell subset frequencies, suggesting that the immune system had been affected. The ZEA+DON-treated groups, especially the group that received a higher concentration of ZEA+DON (Group D2Z2), showed more obvious effects on the dysregulation of splenic antioxidant functions, IFN levels, and T-cell subsets. This finding suggested that DON and ZEA exerted synergistic effects.

Multipotent mesenchymal stromal cells decrease transforming growth factor β1 expression in microglia/macrophages and down-regulate plasminogen activator inhibitor 1 expression in astrocytes after stroke

Multipotent mesenchymal stromal cells (MSCs) decrease the expression of transforming growth factor β1 (TGFβ1) in astrocytes and subsequently decrease astrocytic plasminogen activator inhibitor 1 (PAI-1) level in an autocrine manner. Since activated microglia/macrophages are also a source of TGFβ1 after stroke, we therefore tested whether MSCs regulate TGFβ1 expression in microglia/macrophages and subsequently alters PAI-1 expression after ischemia. TGFβ1 and its downstream effector phosphorylated SMAD 2/3 (p-SMAD 2/3) were measured in mice subjected to middle cerebral artery occlusion (MCAo). MSC treatment significantly decreased TGFβ1 protein expression in both astrocytes and microglia/macrophages in the ischemic boundary zone (IBZ) at day 14 after stroke. However, the p-SMAD 2/3 was only detected in astrocytes and decreased after MSC treatment. In vitro, RT-PCR results showed that the TGFβ1 mRNA level was increased in both astrocytes and microglia/macrophages in an astrocyte-microglia/macrophage co-culture system after oxygen-glucose deprived (OGD) treatment. MSCs treatment significantly decreased the above TGFβ1 mRNA level under OGD conditions, respectively. OGD increased the PAI-1 mRNA in astrocytes in the astrocyte-microglia/macrophage co-culture system, and MSC administration significantly decreased this level. PAI-1 mRNA was very low in microglia/macrophages compared with that in astrocytes under different conditions. Western blot results also verified that MSC administration significantly decreased p-SMAD 2/3 and PAI-1 level in astrocytes in astrocyte-microglia/macrophage co-culture system under OGD conditions. Our in vivo and in vitro data, in concert, suggest that MSCs decrease TGFβ1 expression in microglia/macrophages in the IBZ which contribute to the down-regulation of PAI-1 level in astrocytes.

Multipotent mesenchymal stromal cells increase tPA expression and concomitantly decrease PAI-1 expression in astrocytes through the sonic hedgehog signaling pathway after stroke (in vitro study)

Multipotent mesenchymal stromal cells (MSCs) increase tissue plasminogen activator (tPA) activity in astrocytes of the ischemic boundary zone, leading to increased neurite outgrowth in the brain. To probe the mechanisms that underlie MSC-mediated activation of tPA, we investigated the morphogenetic gene, sonic hedgehog (Shh) pathway. In vitro oxygen and glucose deprivation and coculture of astrocytes and MSCs were used to mimic an in vivo ischemic condition. Both real-time-PCR and western blot showed that MSC coculture significantly increased the Shh level and concomitantly increased tPA and decreased plasminogen activator inhibitor 1 (PAI-1) levels in astrocytes. Inhibiting the Shh signaling pathway with cyclopamine blocked the increase of tPA and the decrease of PAI-1 expression in astrocytes subjected to MSC coculture or recombinant mouse Shh (rm-Shh) treatment. Both MSCs and rm-Shh decreased the transforming growth factor-β1 level in astrocytes, and the Shh pathway inhibitor cyclopamine reversed these decreases. Both Shh-small-interfering RNA (siRNA) and Glil-siRNA downregulated Shh and Gli1 (a key mediator of the Shh transduction pathway) expression in cultured astrocytes and concomitantly decreased tPA expression and increased PAI-1 expression in these astrocytes after MSC or rm-Shh treatment. Our data indicate that MSCs increase astrocytic Shh, which subsequently increases tPA expression and decreases PAI-1 expression after ischemia.

Endogenous tissue plasminogen activator mediates bone marrow stromal cell-induced neurite remodeling after stroke in mice

BACKGROUND AND PURPOSE

Bone marrow stromal cells (BMSC) decrease neurological deficits in rodents after stroke and concomitantly induce extensive neurite remodeling in the brain, which highly correlates with the improvement of neurological function. We investigated the effects of endogenous tissue plasminogen activator (tPA) on neurite remodeling after BMSC treatment.

METHODS

Adult C57BL/6 wild-type (WT) mice and tPA knockout (tPA(-/-)) mice were subjected to middle cerebral artery occlusion, followed by an injection of 1×10(6) BMSC (n=18) or phosphate-buffered saline (n=18) into the tail vein 24 hours later. Behavioral tests were performed at 3, 7, and 14 days after middle cerebral artery occlusion. Animals were euthanized at 14 days after stroke.

RESULTS

The effects of BMSC on functional recovery depended on presence or absence of tPA, even after adjusting for imbalanced stroke severity. BMSC significantly improve functional recovery in WT mice compared to WT controls but show no beneficial effect in the tPA(-/-) mice compared to tPA(-/-) controls. Axonal density and synaptophysin-positive areas along the ischemic boundary zone of the cortex and striatum in WT mice are significantly higher than in the tPA(-/-) mice. BMSC treatment significantly increases tPA protein level and activity only in WT mice.

CONCLUSIONS

Our results suggest that endogenous tPA promotes BMSC-induced neurite outgrowth and may contribute to functional recovery after stroke.

Chronic brain tissue remodeling after stroke in rat: a 1-year multiparametric magnetic resonance imaging study

Rats subjected to 2h of transient middle cerebral artery occlusion were studied temporally over 1 year by magnetic resonance imaging (MRI) and behavioral testing. Multiparameter MRI measures of T(2), T(1), T(1) in the presence of off-resonance saturation of the bound proton signal (T(1sat)), apparent diffusion coefficient (ADC) and susceptibility-weighted imaging (SWI) were obtained at 1 day, 1, 2, 3 and 4 weeks, and 3, 6, 9 and 12 months post-ischemia. Regions of interest included: ischemic core (damaged both at 1 day and later); new lesion (normal at 1 day, but damaged later); and recovery (damaged at 1 day, but normal later) areas. Hematoxylin and eosin, Prussian blue and ED-1, a monoclonal antibody murine macrophage marker, stainings were performed for histological assessment. Core area T(2) and ADC values increased until ~6 months, and T(1) and T(1sat) until ~12 months. New lesion area MRI parameter values increased until ~6 months (T(2), T(1) and ADC), or ~1 year (T(1sat)). Lesion area was largest at 1day (mean±SD: 37.0±13.7mm(2)) and smallest at 1 year (18.1±10.5mm(2)). Recovery area was largest at 3 weeks (8.9±3.8mm(2)) and smallest at 1year (6.4±3.3mm(2)). The ipsilateral/contralateral ventricle area ratio was 0.7±0.2 at 1 day and increased significantly at 1 year (2.4±0.7). Iron-laden macrophages, histologically confirmed at 1 year, were detected in the lesion borders by SWI at 3, 6, 9 and 12 months. Our data indicate that MRI detectable changes of ischemia-damaged brain tissue continue for at least 1 year post-ischemia.

Astrocytic endogenous glial cell derived neurotrophic factor production is enhanced by bone marrow stromal cell transplantation in the ischemic boundary zone after stroke in adult rats

Bone marrow stromal cells (BMSCs) facilitate functional recovery in rats after focal ischemic attack. Growing evidence suggests that the secretion of various bioactive factors underlies BMSCs' beneficial effects. This study investigates the expression of glial cell derived neurotrophic factor (GDNF) in the ischemic hemisphere with or without BMSC administration. Adult male Wistar rats were subjected to 2 h of middle cerebral artery occlusion followed by an injection of 3 x 10(6) BMSCs (n = 11) or phosphate-buffered saline (n = 10) into the tail vein 24 h later. Animals were sacrificed seven days later. Single and double immunohistochemical staining was performed to measure GDNF, Ki67, doublecortin, and glial fibrillary acidic protein expression as well as the number of apoptotic cells along the ischemic boundary zone (IBZ) and/or in the subventricular zone (SVZ). BMSC treatment significantly increased GDNF expression and decreased the number of apoptotic cells in the IBZ (P < 0.05). GDNF expression was colocalized with GFAP. Meanwhile, BMSCs increased the number of Ki-67 positive cells and the density of DCX positive migrating neuroblasts (P < 0.05). GDNF expression was significantly increased in single astrocytes collected from animals treated with BMSCs, and in astrocytes cocultured with BMSCs after OGD (P < 0.05). Our data suggest that BMSCs increase GDNF levels in the ischemic hemisphere; the major source of GDNF protein is reactive astrocytes. We propose that the increase of GDNF in response to BMSC administration creates a hospitable environment for local cellular repair as well as for migrating neuroblasts from the SVZ, and thus contributes to the functional improvement.

Localization of bone marrow stromal cells to the injury site after intracerebral hemorrhage in rats

OBJECT

Previous studies demonstrated that intravascular injection of bone marrow stromal cells (BMSCs) significantly improved neurological functional recovery in a rat model of intracerebral hemorrhage (ICH). To further investigate the fate of transplanted cells, we examined the effect of male rat BMSCs administered to female rats after ICH.

METHODS

Twenty-seven female Wistar rats were subjected to ICH surgery. At 24 hours after ICH, these rats were randomly divided into 3 groups and injected intravenously with 1 ml phosphate-buffered saline or 0.5 million or 1 million male rat BMSCs in phosphate-buffered saline. To evaluate the neurological functional outcome, each rat was subjected to a series of behavioral tests (modified neurological severity score and corner turn test) at 1, 7, and 14 days after ICH. The rats were anesthetized intraperitoneally and killed, and the brain tissues were processed at Day 14 after ICH. Immunohistochemistry and in situ hybridization were used to identify cell-specific markers.

RESULTS

The male rat BMSCs significantly improved the neurological functional outcome and also significantly diminished tissue loss when intravenously transplanted into the rats after ICH. Immunoassay for bromodeoxyuridine (BrdU) and neuronal markers demonstrated a significant increase in the number of BrdU-positive cells, which indicated endogenous neurogenesis, and a significant increase in the number of cells positive for immature neuronal markers. In situ hybridization showed that more BMSCs resided around the hematoma of the rats treated with the 1-million-cell dose compared with the 0.5-million-cell-dose group. In addition, a subfraction of Y chromosome-positive cells were co-immunostained with the neuronal marker microtubule-associated protein-2 or the astrocytic marker glial fibrillary acidic protein.

CONCLUSIONS

Male rat BMSCs improve neurological outcome and increase histochemical parameters of neurogenesis when administered to female rats after ICH. This study has shown that the intravenously administered male rat BMSCs enter the brain, migrate to the perihematomal area, and express parenchymal markers.

Increasing tPA activity in astrocytes induced by multipotent mesenchymal stromal cells facilitate neurite outgrowth after stroke in the mouse

We demonstrate that tissue plasminogen activator (tPA) and its inhibitors contribute to neurite outgrowth in the central nervous system (CNS) after treatment of stroke with multipotent mesenchymal stromal cells (MSCs). In vivo, administration of MSCs to mice subjected to middle cerebral artery occlusion (MCAo) significantly increased activation of tPA and downregulated PAI-1 levels in the ischemic boundary zone (IBZ) compared with control PBS treated mice, concurrently with increases of myelinated axons and synaptophysin. In vitro, MSCs significantly increased tPA levels and concomitantly reduced plasminogen activator inhibitor 1 (PAI-1) expression in astrocytes under normal and oxygen and glucose deprivation (OGD) conditions. ELISA analysis of conditioned medium revealed that MSCs stimulated astrocytes to secrete tPA. When primary cortical neurons were cultured in the conditioned medium from MSC co-cultured astrocytes, these neurons exhibited a significant increase in neurite outgrowth compared to conditioned medium from astrocytes alone. Blockage of tPA with a neutralizing antibody or knock-down of tPA with siRNA significantly attenuated the effect of the conditioned medium on neurite outgrowth. Addition of recombinant human tPA into cortical neuronal cultures also substantially enhanced neurite outgrowth. Collectively, these in vivo and in vitro data suggest that the MSC mediated increased activation of tPA in astrocytes promotes neurite outgrowth after stroke.

The synthesis and characterization of [(124)I]IMPY, a thioflavin-S derivative, in transgenic mouse models of Alzheimer's disease

6-[(124)I]iodo-2-(4'-N,N-dimethylamino)-phenylimidazo[1,2-a]pyridine ([(124)I]IMPY) was synthesized and characterized as a positron-emitting probe to identify Alzheimer's disease in transgenic mouse models. A significant reduction in radioactivity retention in the hippocampus and frontal cortex by co-incubation with nonradioactive IMPY was observed. Highly specific retention of radioactivity in beta-amyloid-rich regions of brain sections was also noted. This study demonstrated that [(124)I]IMPY was a promising probe for the mouse model and may be useful for positron emission tomography to image beta-amyloid plaques in the human brain.

Down-regulation of neurocan expression in reactive astrocytes promotes axonal regeneration and facilitates the neurorestorative effects of bone marrow stromal cells in the ischemic rat brain

The glial scar, a primarily astrocytic structure bordering the infarct tissue inhibits axonal regeneration after stroke. Neurocan, an axonal extension inhibitory molecule, is up-regulated in the scar region after stroke. Bone marrow stromal cells (BMSCs) reduce the thickness of glial scar wall and facilitate axonal remodeling in the ischemic boundary zone. To further clarify the role of BMSCs in axonal regeneration and its underlying mechanism, the current study focused on the effect of BMSCs on neurocan expression in the ischemic brain. Thirty-one adult male Wistar rats were subjected to 2 h of middle cerebral artery occlusion followed by an injection of 3 x 10(6) rat BMSCs (n = 16) or phosphate-buffered saline (n = 15) into the tail vein 24 h later. Animals were sacrificed at 8 days after stroke. Immunostaining analysis showed that reactive astrocytes were the primary source of neurocan, and BMSC-treated animals had significantly lower neurocan and higher growth associated protein 43 expression in the penumbral region compared with control rats, which was confirmed by Western blot analysis of the brain tissue. To further investigate the effects of BMSCs on astrocyte neurocan expression, single reactive astrocytes were collected from the ischemic boundary zone using laser capture microdissection. Neurocan gene expression was significantly down-regulated in rats receiving BMSC transplantation (n = 4/group). Primary cultured astrocytes showed similar alterations; BMSC coculture during reoxygenation abolished the up-regulation of neurocan gene in astrocytes undergoing oxygen-glucose deprivation (n = 3/group). Our data suggest that BMSCs promote axonal regeneration by reducing neurocan expression in peri-infarct astrocytes.

One-year follow-up after bone marrow stromal cell treatment in middle-aged female rats with stroke

BACKGROUND AND PURPOSE

We sought to evaluate the long-term effects of bone marrow stromal cell (BMSC) treatment on retired breeder rats with stroke.

METHODS

Female retired breeder rats were subjected to 2-hour middle cerebral artery occlusion (MCAO) followed by an injection of 2 x 10(6) male BMSCs (n=8) or phosphate-buffered saline (n=11) into the ipsilateral internal carotid artery at 1 day after stroke. The rats were humanely killed 1 year later. Functional tests, in situ hybridization, and histochemical and immunohistochemical staining were performed.

RESULTS

Significant recovery of neurological deficits was found in BMSC-treated rats beginning 2 weeks after cell injection compared with control animals. The beneficial effects of cell transplantation persisted for at least 1 year (P<0.01). In situ hybridization for the Y chromosome showed that donor cells survived in the brains of recipient rats, among which 22.3+/-1.95% of cells expressed the astrocyte marker glial fibrillary acidic protein, 16.8+/-2.13% expressed the neuronal marker microtubule-associated protein 2, and 5.5+/-0.42% and <1% of cells colocalized with the microglial marker IB4 and the endothelial cell marker von Willebrand factor, respectively. Only very few BMSCs, however, were found in peripheral organs such as the heart, lung, liver, spleen, and kidney in recipient rats. BMSCs significantly reduced axonal loss (P<0.01), the thickness of the lesion scar wall (P<0.01), and the number of Nogo-A-positive cells (P<0.05) along the scar border; meanwhile, synaptophysin expression (P<0.05) was significantly increased in BMSC-treated ischemic brains compared with control untreated brains.

CONCLUSIONS

The beneficial effects of BMSCs on ischemic brain tissue persisted for at least 1 year. Most surviving BMSCs were present in the ischemic brain, but very few were found in other organs. The long-term improvement in functional outcome may be related to the structural and molecular changes induced by BMSCs.

Therapeutic benefit of bone marrow stromal cells administered 1 month after stroke

Bone marrow stromal cells (BMSCs) facilitate functional recovery in rats after stroke when administered acutely (1 day) or subacutely (7 days). In this study, we postponed the time of cell transplantation to 1 month after stroke. Female retired breeder rats were subjected to 2 h of middle cerebral artery occlusion (MCAo). Male BMSCs (3 x 10(6)) or phosphate-buffered saline were administered intravenously, and the animals were killed 3 months later. An additional population of nontreated rats was killed at 1 month after MCAo. Significant recovery of behavior was found in BMSC-treated rats beginning at 1 month after cell injection in the modified neurologic severity score test and the adhesive-removal test compared with control animals (P<0.05). In situ hybridization showed that BMSCs survived and preferentially localized to the ipsilateral hemisphere. Double staining revealed that approximately 13% and 6% Y-chromosome-positive cells expressed the astrocyte marker, glial fibrillary acidic protein, and the neuronal marker, microtubule-associated protein-2, respectively. In addition, BMSC treatment reduced scar thickness, and increased the number of proliferating cells and oligodendrocyte precursor cells along the subventricular zone in the ipsilateral hemisphere. Expression of the chemokine stromal-cell-derived factor-1 (SDF-1) was significantly increased along the ischemic boundary zone compared with the corresponding areas in the contralateral hemisphere at 1 month and 4 months (P<0.01) after stroke. The SDF-1 receptor, CXC-chemokine receptor-4 (CXCR4), was expressed in BMSCs both in vitro and in vivo. Our data show that the time window of BMSC therapy is at least 1 month after stroke; the interaction of SDF-1/CXCR4 may contribute to the trafficking of transplanted BMSCs.

Investigation of recombinant Schistosoma japonicum paramyosin fragments for immunogenicity and vaccine efficacy in mice

Schistosoma japonicum paramyosin, a 97 kDa myofibrillar protein, is a recognized vaccine candidate against schistosomiasis. To improve its expression and to identify protective epitopic regions on paramyosin, the published Chinese Schistosoma japonicum paramyosin cDNA sequence was redesigned using Pichia codon usage and divided into four overlapping fragments (fragments 1, 2, 3, 4) of 747, 651, 669 and 678 bp, respectively. These gene fragments were synthesized and expressed in Pichia pastoris (fragments 2 and 3) or E. coli (fragments 1 and 4). The recombinant proteins were produced at high level and purified using a two-step process involving Ni-NTA affinity chromatography and gel filtration. BALB/c mice were immunized subcutaneously three times at 2-week-intervals with the purified proteins formulated in adjuvant Quil A. The protein fragments were highly immunogenic, inducing high, though variable, ELISA antibody titres, and each was shown to resemble native paramyosin in terms of its recognition by the anti-fragment antibodies in Western blotting. The immunized mice were subjected to cercarial challenge 2 weeks after the final injection and promising protective efficacy in terms of significant reductions in worm burdens, worm-pair numbers and liver eggs in the vaccinated mice resulted. There was no apparent correlation between the antibody titres generated and protective efficacy, as all fragments produced effective but similar levels of protection.

Intracarotid transplantation of bone marrow stromal cells increases axon-myelin remodeling after stroke

The present study investigates the induction of axon and myelin remodeling as a possible mechanism by which treatment of stroke with bone marrow stromal cells improves neurological functional recovery. Adult male Wistar rats were subjected to 2 h of middle cerebral artery occlusion, followed by an injection of 2 x 10(6) rat bone marrow stromal cells or phosphate-buffered saline into the internal carotid artery 24 h later. Animals were killed at 28 days after stroke. Functional tests, histo- and immunohistochemical staining were performed. Significant functional recovery was found after bone marrow stromal cell administration in all the three tests performed (modified neurological severity score, adhesive-removal and corner tests). Bone marrow stromal cell treatment markedly increased vessel sprouting, synaptophysin expression and NG2 positive cell numbers and density in the cortical peri-infarct area. In bone marrow stromal cell-treated rats, the number of Ki-67 positive proliferating cells and oligodendrocyte precursor cells in the corpus callosum increased significantly in concert with the enhancement of the areas of the corpus callosum in both hemispheres. These results suggest that bone marrow stromal cells facilitate axonal sprouting and remyelination in the cortical ischemic boundary zone and corpus callosum, which may underlie neurological functional improvement caused by bone marrow stromal cell treatment.

Gliosis and brain remodeling after treatment of stroke in rats with marrow stromal cells

The long-term (4-month) responses to treatment of stroke in the older adult rat, using rat bone marrow stromal cells (MSCs), have not been investigated. Retired breeder rats were subjected to middle cerebral artery occlusion (MCAo) alone, or injected intravenously with 3 x 10(6) MSCs, at 7 days after MCAo. Functional recovery was measured using an adhesive-removal patch test and a modified neurological severity score. Bromodeoxyuridine, a cell proliferation marker, was injected daily for 14 before sacrifice. Animals were sacrificed 4 months after stroke. Double immunostaining was used to identify cell proliferation and cell types for axons, astrocytes, microglia, and oligodendrocytes. MSC treatment induced significant improvement in neurological outcome after MCAo compared with control rats. MSC treatment reduced the thickness of the scar wall (P < 0.05) and reduced the numbers of microglia/macrophages within the scar wall (P < 0.01). Double staining showed increased expression of an axonal marker (GAP-43), among reactive astrocytes in the scar boundary zone and in the subventricular zone in the treated rats. Bromodeoxyuridine in cells preferentially colocalized with markers of astrocytes (GFAP) and oligodendrocytes (RIP) in the ipsilateral hemisphere, and gliogenesis was enhanced in the subventricular zone of the rats treated with MSCs. This is the first report to show that MSCs injected at 7 days after stroke improve long-term neurological outcome in older animals. Brain tissue repair is an ongoing process with reactive gliosis, which persists for at least 4 months after stroke. Reactive astrocytes responding to MSC treatment of ischemia may also promote axonal regeneration during long-term recovery.

Histologic study of effects of radiation synovectomy with Rhenium-188 microsphere

Rhenium-188 microsphere is a relatively new radiation synovectomy agent developed for the treatment of rheumatoid arthritis. It has been shown that the levels of unwanted extra-articular radiation are negligible with this agent. A histologic study was conducted to assess the effect of radiation synovectomy on synovium and articular cartilage after intra-articular injection of various doses of Re-188 microspheres into the knee joints of rabbits. Intra-articular injection of Re-188 microspheres into rabbit knee joints resulted in mild reactive inflammation and thrombotic occlusion of vessels which subsided rapidly. Sclerosis of subsynovium could be seen 12 weeks after injection. No evidence of damage to articular cartilage was noted. There was no significant difference in the articular pattern after injection of 0.3 or 0.6 mCi Re-188 microspheres. This study suggests that a treatment dose of Re-188 microspheres causes transient inflammation of synovium without any detectable damage to the articular cartilage of knee joint.

Phosphorylation of caldesmon by p21-activated kinase. Implications for the Ca(2+) sensitivity of smooth muscle contraction

We have previously shown that p21-activated kinase, PAK, induces Ca(2+)-independent contraction of Triton-skinned smooth muscle with concomitant increase in phosphorylation of caldesmon and desmin but not myosin-regulatory light chain (Van Eyk, J. E., Arrell, D. K., Foster, D. B., Strauss, J. D., Heinonen, T. Y., Furmaniak-Kazmierczak, E., Cote, G. P., and Mak, A. S. (1998) J. Biol. Chem. 273, 23433-23439). In this study, we provide biochemical evidence implicating a role for PAK in Ca(2+)-independent contraction of smooth muscle via phosphorylation of caldesmon. Mass spectroscopy data show that stoichiometric phosphorylation occurs at Ser(657) and Ser(687) abutting the calmodulin-binding sites A and B of chicken gizzard caldesmon, respectively. Phosphorylation of Ser(657) and Ser(687) has an important functional impact on caldesmon. PAK-phosphorylation reduces binding of caldesmon to calmodulin by about 10-fold whereas binding of calmodulin to caldesmon partially inhibits PAK phosphorylation. Phosphorylated caldesmon displays a modest reduction in affinity for actin-tropomyosin but is significantly less effective in inhibiting actin-activated S1 ATPase activity in the presence of tropomyosin. We conclude that PAK-phosphorylation of caldesmon at the calmodulin-binding sites modulates caldesmon inhibition of actin-myosin ATPase activity and may, in concert with the actions of Rho-kinase, contribute to the regulation of Ca(2+) sensitivity of smooth muscle contraction.

Pentavalent Tc-99m dimercaptosuccinic acid imaging of hepatocellular carcinoma

Tc-99m (V)-dimercaptosuccinic acid (DMSA) has been used to image various kinds of tumors. However, from a review of the literature, it has never been applied to hepatocellular carcinoma (HCC). Low uptake of Tc-99m (V)-DMSA has been demonstrated in normal liver tissue, thus, Tc-99m (V)-DMSA may be useful for the detection of HCC. Nine male patients with focal nodular HCC were studied with sequential X-ray CT, Tc-99m (V)-DMSA and Tc-99m phytate liver scan. Our data showed that eight patients had increased uptake of Tc-99m (V) DMSA in HCC. Four cases demonstrated higher Tc-99m (V) DMSA uptake in HCC than in adjacent liver, and four cases demonstrated HCC uptake equal to liver uptake. One case showed no uptake of Tc-99m (V) DMSA in HCC. The detection sensitivity of Tc-99m (V)-DMSA was 88.9%. From our early results, Tc-99m (V)-DMSA is a readily available tumor imaging agent that appears to accumulate in HCC.

Ischemic preconditioning mediated by activation of KATP channels in rat small intestine

AIM

To study whether the protective effects of ischemic preconditioning against rat small intestine ischemia/reperfusion injury could be mediated by KATP channel opener.

METHODS

Preconditioning (Pc) was induced by 3 cycles of 8-min superior mesenteric artery (SMA) occlusion and 10-min reperfusion before prolonged ischemia. Cromakalim (Cro 75 micrograms.kg-1) and glibenclamide (Gli 8 mg.kg-1) were injected i.v. 10 min before prolonged ischemia and Pc, respectively.

RESULTS

Compared with ischemic reperfusion (IR) group, Pc before prolonged ischemia (Pc + IR) decreased LDH release [(380 +/- 55) vs (559 +/- 49) U.L-1, P < 0.05], attenuated intestinal edema [wet weight/dry weight (WW/DW), 5.6 +/- 0.6 vs 6.34 +/- 0.29, P < 0.05], ameliorated intestinal histological damage (grading scale, 3.4 vs 5.7, P < 0.01), and improved reperfusion-induced hypotension. These effects of Pc were mimicked by Cro [LDH, (298 +/- 40) vs (559 +/- 49) U.L-1, P < 0.05; WW/DW, 5.6 +/- 0.4 vs 6.34 +/- 0.29, P < 0.05; grading scale, 3.6 vs 5.7, P < 0.01] and abolished in the presence of Gli [LDH, (624 +/- 44) vs (559 +/- 49) U.L-1; WW/DW, 6.6 +/- 0.6 vs 6.34 +/- 0.29; grading scale, 5.7 vs 5.7; P > 0.05] compared with IR group, respectively.

CONCLUSION

Ischemic preconditioning on the rat small intestine is mediated by activation of KATP channels.

Intratumoral injection of rhenium-188 microspheres into an animal model of hepatoma

Intratumoral injection of 90Y microspheres is a potential alternative in the treatment of primary liver tumor. However, complicated preparation and lack of a gamma ray for imaging are the disadvantages of 90Y. In this study, we used 188Re, a generator-produced radioisotope with 155-keV gamma ray emission, to label microspheres. After intratumoral injection of 188Re microspheres into rats with hepatoma, biodistributions and survival times were analyzed.

METHODS

Twelve male rats with hepatoma were killed at 1, 24 and 48 hr (4 rats at each time point) after intratumoral injection of approximately 7.4 MBq 188Re microspheres. Samples of various organs were obtained and used to calculate the tissue concentrations. In addition, 30 male rats bearing hepatoma were divided into two groups (15 rats in each group) to evaluate survival time. Group 1 received intratumoral injection of 37 MBq 188Re microspheres, whereas Group 2 served as the control group and received an intratumoral injection of 0.1 ml normal saline only. Survival time was calculated from the day of injection to 2 mo after treatment.

RESULTS

Radioactivity in the tumor was very high throughout. Biological half-time was 170.8 hr. Radioactivity in the lung was 1.78% injected dose (i.d.)/g at 1 hr but declined rapidly over time. The concentration in the urine was approximately 6.14% i.d./ml after the first hour and rapidly declined thereafter. The concentrations of radioactivity in other organs, such as normal liver, muscle, spleen, bone, testis and whole blood, were quite low throughout the study. Twelve of 15 (80%) of rats survived over 60 days after intratumoral injection of 188Re microspheres, whereas only 4 of 15 (26.7%) survived more than 60 days after injection of normal saline only. The difference between the groups was significant (p < 0.05).

CONCLUSION

Rhenium-188 offers cost-effectiveness, on-site availability, short half-life, energetic beta particle, emission of gamma photons for imaging, easy preparation, easy clinical administration and apparent lack of radiation leakage from the treated tumor. Direct intratumoral injection of 188Re microspheres is extremely attractive as a clinical therapeutic alternative in hepatoma patients.

Rhenium-188 microspheres: a new radiation synovectomy agent

Radiation synovectomy is efficacious in controlling the symptoms of rheumatoid arthritis. However, the procedure is not widely used because of concerns about leakage of radiopharmaceuticals from the treated joints. Leakage can be minimized by selecting particles of an appropriate size. In this study, we labelled microspheres with 188Re and analysed its biodistribution after intra-articular injection in rabbits with antigen-induced arthritis. Gamma camera imaging was performed to quantify the mean retention of 188Re in the knees. The mean retention of 188Re was 98.7, 94.6 and 93.6% at 1, 24 and 48 h, respectively. The biodistribution data revealed very low radioactivity in all organs at different times, which suggests the leakage of radiotracer from the knee was negligible. Our preliminary results indicate that 188Re microspheres are a potentially effective radiopharmaceutical for radiation synovectomy.

Disparities in mean age and histopathologic grade between human papillomavirus type-specific early cervical neoplasms

Noninvasive squamous and glandular precursor lesions associated with human papillomavirus (HPV) types 16 and 18 have been reported to vary in morphology. HPV 16 is associated predominantly with high-grade squamous intraepithelial lesions (HSIL; cervical intraepithelial neoplasia (CIN 2 and 3), and HPV 18 is associated with low-grade squamous intraepithelial lesions (condyloma/CIN 1) and CIN 3/adenocarcinoma in situ (ACIS). This study explored the relationship of morphologic growth pattern in these precursor groups with age of presentation. One hundred fourteen CIN lesions (including those with ACIS), associated with HPV 16 or 18, were subdivided into well-differentiated low- and high-grade SIL (CIN 1 and 2, respectively), poorly differentiated HSIL (CIN 3) with or without ACIS. HPV was detected by polymerase chain reaction (PCR) amplification with L1 consensus or type-specific E7 primers and typed by restriction fragment length polymorphism (RFLP) analysis. Age of the patient was obtained from the pathology report. Mean age for each group was as follows: Low-risk HPVs, 25 years; HPV 18 CIN 1-2, 21.6 yrs; HPV 18 CIN 3/ACIS, 35.2 yrs; HPV 16 CIN 1,2, 25.9 yrs; and HPV 16 CIN 3, 29.8 yrs. There were significant differences in mean ages between HPV 18 CIN 1 and 2 and HPV 16 CIN 1 to 2 (P = .04), HPV 16 CIN 1-2 and CIN 3 (P = .01) and HPV 18 CIN 1 to 2 and HPV 18 CIN 3/ACIS (P = .00001). None of the cases of HPV 18-associated CIN3/ACIS was associated with a CINI lesion. The disparity in mean ages between well and poorly differentiated HPV 16/18 related that precursor lesions could reflect factors such as morphologic progression with increasing age, different rates of lesion persistence, depending on grade, or efficiency of detection between the two groups. The marked difference in mean age between HPV 18-associated CIN 1-2 and CIN 3/ACIS, combined with their lack of coexistence in the same cervix, raises alternate possibilities that specific viral or host factors may determine the morphological phenotype associated with some HPV 18 infections. In the latter, the possibility that age independently confers an increased risk for higher-grade lesions should be considered.

Low prevalence of human papillomavirus infection in esophageal squamous cell carcinomas from North America: analysis by a highly sensitive and specific polymerase chain reaction-based approach

Several studies have documented the frequent occurrence of human papillomavirus (HPV) DNA in esophageal squamous cell carcinomas (ESCC) in patients from geographic regions where the incidence of this type of cancer is high, such as parts of China. However, the prevalence of HPV infection in ESCC in patients from low incidence geographic regions, such as North America, remains controversial. Therefore, this study evaluates the prevalence of HPV in ESCC in patients from North America, a region where the population is considered at low risk for the development of this neoplasm. ESCCs in 51 patients from three North American cities were analyzed for the presence of HPV DNA by a highly sensitive and specific polymerase chain reaction (PCR) method. Tumor DNA was extracted from formalin-fixed, paraffin-embedded tissue specimens and assayed by PCR using an L1 HPV consensus sequence primer, as well as HPV 16 and HPV 18 E7 region primers. The use of consensus primers to the L1 region allows for detection of most known HPV types and many novel HPV types. Appropriately sized reaction products were analyzed by restriction fragment length polymorphism (RFLP) to confirm the presence and type of HPV, and to exclude products produced by amplification of human DNA sequences. After complete analysis, only one case (2%) of ESCC was HPV DNA positive. This case was independently confirmed using L1 and E7 consensus primers as HPV type 16 and was the only case that tested positive with either assay. These results show that, in contrast to geographic regions where ESCC is prevalent, HPV infection occurs infrequently in association with ESCC in patients from North America.

[The study on the in-vitro stability of Tc(V)-99m dimercaptosuccinic acid]

Tc(V)-99m DMS, developed by Yokoyama et al. in 1981, has been recognized to be advantageous for the scintigraphic diagnosis of various malignant tumors and their metastasis, the aim of this study is to assess the in-vitro stability of Tc(V)-99m DMS. Thin-layer chromatography, including paper chromatography and silica gel thin layer chromatography, is performed to determine the change of radiochemical species presented in the reconstituted solution of Tc(V)-99m DMS prepared from the DMS kit (Institute of Nuclear Energy Research, Atomic Energy Council R.O.C.) and the commercial DMSA kit (Nephroscint, IRE CELLTARG Radiopharmaceuticals Japan). The bioscan imaging scanner is used to measure the Rf value and labeling efficiency of radiochemical species on the chromatographic strip. The in-vitro stability of Tc(V)-99m DMS prepared from the DMS kit and the commercial DMSA kit is studied by examining various parameters which include temperature(degree C) and time(hr) after reconstitution. The results show that the in-vitro stability of Tc(V)-99m DMS prepared from the DMS kit is actually better than that from the commercial DMSA kit. The one-step labeling method of DMS kit is much simpler than the two-step labeling method of DMSA kit.

Radiolabelling of Lipiodol with generator-produced 188Re for hepatic tumor therapy

In this study we prepared and analyzed the biodistribution of 188Re-labelled Lipiodol ([188Re]-Lipiodol) in rats after intrahepatic arterial injection. EDTB was synthesized by condensation of 1,2-benzenediamine and ethylenediaminetetraacetic acid (EDTA). The labelling efficiency of [188Re] Lipiodol was determined to be greater than 97% by ITLC developed with n-hexane. Following incubation of the [188Re] Lipiodol with an equal volume of serum at 37 degrees C for 48 h, ITLC indicated good in vitro stability. Approximately 7.4 MBq [188Re] Lipiodol was injected in each rat via the hepatic artery and samples of liver, spleen, muscle, lung, kidney, bone, whole blood and testis were obtained. [188Re] Lipiodol tissue concentrations showed that after 1 h intrahepatic injection most of the radiotracer was retained in the liver, and was eliminated slowly with a biological half-life of 33.5 h. Radioactvity levels in the lung, kidney and blood were moderate at 1 h, and declined rapidly over time. In the spleen, muscle, testis and bone, radiation levels were insignificant. These initial results indicate that -188Re- Lipiodol may be a potential radiopharmaceutical agent for the treatment of liver tumors.

Biodistribution of rhenium-188 Lipiodol infused via the hepatic artery of rats with hepatic tumours

The purpose of this study was to analyse the biodistribution of rhenium-188 Lipiodol in rats with hepatic tumours following intrahepatic arterial injection to assess the potential of 188Re-Lipiodol as a radiopharmaceutical for the treatment of hepatic tumours in humans. Twelve male rats with hepatic tumours were killed at 1h, 24h and 48h after injection of approximately 7.4MBq of 188Re-Lipiodol via the hepatic artery. Samples of various organs were obtained and counted to calculate the tissue concentration. Radioactivity in the hepatic tumours was very high throughout this study, with a biological half-life of 122.9h. Radioactivity in the normal liver tissue was also high, but was significantly lower than in the tumour. The biological half-life in the normal liver tissue was 31.7h. The ratio of tumour concentration to the normal liver tissue concentration was 5.15 at 1h and rose to 7.7 at 24h and 10.84 at 48h. The level of radioactivity in the lung was high at 1h, and declined rapidly over time. The level of radioactivity in the kidney was moderate throughout the study. The radiation concentrations in muscle, spleen, testis, bone and whole blood were insignificant. We conclude that 188Re-Lipiodol should be considered as a potential radiopharmaceutical for the intra-arterial treatment of hepatic tumours.

Prevalence and histologic significance of cervical human papillomavirus DNA detected in women at low and high risk for cervical neoplasia

OBJECTIVES

To determine and compare the prevalence and histologic significance of human papillomavirus (HPV) nucleic acids in cervical specimens from women at low (routine hysterectomy) and high (suspicion of cervical neoplasia) risk for cervical neoplasia.

METHODS

Cervical brushings were taken from the cervices of hysterectomy and conization or loop electrical excision specimens and analyzed for HPV nucleic acids by polymerase chain reaction and restriction fragment length polymorphism analysis. Histopathology was confirmed by review of reports or, for HPV-positive results, re-review of the histopathology. Statistical analysis used Student t test or Fisher exact test.

RESULTS

Four hundred seventeen and 43 low- and high-risk cervices, respectively, were studied. Statistically significant differences were observed in the index of HPV positivity between the low- and high-risk groups (1.7 versus 42%, P < .001) and the proportion of HPV being cancer-associated HPV types (14 versus 78%, P = .005). None of the 417 cervices from low-risk women contained HPV 16. In the high-risk group, histologically confirmed cervical intraepithelial neoplasia lesion was statistically more likely to be associated with HPV (59 versus 13%, P = .005).

CONCLUSION

Cervices from routine, low-risk hysterectomies in predominately middle-aged women have an extremely low index of cancer-associated HPVs. Considering the strong association of HPV with histologically proven disease, prospective studies exploring the relationship of cancer-associated HPVs to neoplasia in middle-aged women merit consideration.

Rhenium-188 sulphur colloid as a radiation synovectomy agent

Radiation synovectomy has been shown to be an effective treatment for the rheumatoid arthritic knee. In this study, we evaluated the suitability of rhenium-188 as a radiation synovectomy agent. In addition, we were successful in labelling sulphur colloid with 188Re. In vitro stability tests revealed that more than 95% of the 188Re remained in colloid form over a 3-day period. Intra-articular injection of 188Re sulphur colloid into arthritic rabbit joints was followed by gamma camera imaging to quantify the leakage. The mean retention percentages of 188Re colloid in arthritic knees were 93.7% (+/- 1.4%), 90.8% (+/- 1.7%) and 87.2% (+/- 0.6%) at 1 h, 1 day and 2 days, respectively. A biodistribution study of the arthritic rabbits revealed that the highest activity outside the knees was in the liver and the kidneys. Our preliminary results indicate that 188Re sulphur colloid may be an effective radiopharmaceutical for radiation synovectomy.

Preparation and biodistribution of yttrium-90 Lipiodol in rats following hepatic arterial injection

In this study, we labelled Lipiodol with yttrium-90 and analysed the biodistribution in rats after intrahepatic arterial injection. An RP-18 column (E. Merck) was used to separate 90Y from strontium-90. 90Y was retained on the column, which had been pretreated with yttrium-selective extraction reagent, di(2-ethylhexyl) phosphate, while 90Sr was washed out. A hexadentate nitrogen-donor chelating ligand N,N,N',N'-tetrakis(2-benzymidazolylmethyl)-1,2-ethanediamine (EDTB) was synthesized by condensation of 1,2-benzenediamine and ethylene diamine tetra-acetic acid (EDTA). Lipiodol was covalently conjugated with EDTB. The final product was obtained by eluting the retained 90Y from the RP-18 column with EDTB-Lipiodol. Sixteen male rats (Sprague-Dawley) were sacrificed at 1 h, 24 h, 48 h and 72 h (four rats at each time) after injection of approximately 0.1 mCi 90Y-Lipiodol via the hepatic artery. Samples of liver, spleen, muscle, lung, kidney, bone, whole blood and testis were obtained and counted to calculate the tissue concentrations. In addition, labelling efficiency and in vitro stability were determined by ITLC methods. We found that at 1 h after intrahepatic injection, most of the radiotracer was retained in the liver, but it was eliminated gradually over a few days. The radioactivity level in the lung was fair at 1 h and remained at roughly the same level throughout the study. Radioactivity in the kidney and spleen reached a relatively high level at 24 h, but declined rapidly.(ABSTRACT TRUNCATED AT 250 WORDS)

Modification of an in-vitro method for estimating the bioavailability of zinc and calcium from foods

A continuous flow in-vitro method for estimating the bioavailability of minerals and trace elements was modified. This modified method includes a simulated gastric digestion with pepsin, gradual pH change during the first 30 min of dialysis in an Amicon stirred cell, and a further 2 h of continuous dialysis accompanied by intestinal digestion with pancreatin-bile extract. The percentage of continuously dialysed minerals or trace elements (dialysability) is used to express the bioavailability. Comparison of different in-vitro methods by using the dialysability of zinc and calcium from milk- and soy-based formula samples revealed that with the modified method the results are closer to the in-vivo situation and could be used as a relative index for predicting the bioavailability of some minerals and trace elements.

[Overexpression of c-erbB-2 proto-oncogene product in chondrosarcomas]

The c-erbB-2 proto-oncogene plays an important role in the regulation of cellular proliferation and differentiation. Overexpression of c-erbB-2 proto-oncogene product in 40 cases of chondrosarcomas was investigated using ABC immunoperoxidase method. Overexpression of c-erbB-2 product was present in 36/40 (90%) chondrosarcomas and in 1/9 (11%) benign cartilage tumors. Normal cartilage tissue gave negative results. These findings indicate that c-erbB-2 proto-oncogene product has practical value in diagnosing chondrosarcomas. c-erbB-2 positive grading showed a significant inverse correlation with the histopathological grading. Chondrosarcomas with high histological grade and poor differentiation showed a bias toward a decline in expression of c-erbB-2 product. The c-erbB-2 proto-oncogene product may be used as a differentiation marker.

Evaluation of various methods of 99Tcm-human immunoglobulin preparation in scintigraphic detection of infection

Radiolabelled human immunoglobulin (HIG) scintigraphy has been recognized as a reliable modality for the localization and evaluation of pyogenic infection in humans. Four methods of labelling HIG with 99Tcm developed by the Institute of Nuclear Energy Research of Taiwan are: (1) using ascorbic acid (ASC) for direct labelling of HIG (ASC-HIG); (2) using diethylenetriamine pentaacetate (DTPA) as a bifunctional chelate (DTPA-HIG); (3) using 2-iminothiolane (IM) for modified protein (IM-HIG); (4) using the avidin-biotin system (AVI-BIO-HIG). Our study assessed these four preparations in the scintigraphic detection of infections. Staphylococcus aureus was injected intramuscularly into the left thighs of rabbits. Two days later, when active inflammation developed, 5 mCi 99Tcm-HIG was given intravenously; scintigraphy was performed at 1, 4 and 18 h. The accumulation of 99Tcm DTPA-HIG was the most prominent among the four preparations at the site of infection. It is concluded that 99Tcm labelling of HIG using DTPA as a bifunctional chelate may be the optimal labelling method for detecting infection.

The detection of nasopharynx carcinoma in technetium-99m (V) dimercaptosuccinic acid SPECT imaging

Twenty-seven patients (24 men, 3 women; ages: 39-74 years) were diagnosed as having squamous cell carcinoma of the nasopharynx (NPC) as confirmed by pathologic findings of biopsies. In addition, three of the 27 patients had metastases to neck lymph nodes. The results of 2-4-hour SPECT images of the head and neck after intravenous injection of 15-20 mCi of Tc-99m (V) DMSA were compared with normal Tc-99m (V) DMSA images and CT of heads and necks. The results showed that of the 27 NPC cases, none of the patients had a significant uptake of Tc-99m (V) DMSA. However, in the three cases complicated with metastases of neck lymph nodes, the metastatic lesions could be detected by Tc-99m (V) DMSA. Our results challenge previous reports in which carcinomas of the head and neck were detected by Tc-99m (V) DMSA. The tumor-seeking agent Tc-99m (V) DMSA is not a good choice for the detection of NPC among malignancies of the head and neck.

Using technetium-99m (V) dimercaptosuccinic acid to detect malignancies from single solid masses in the lungs

Fifty patients (43 male, 7 female, age 31-77 years) with single solid masses in their lungs based on the findings of a chest X-radiograph [40 malignancies: 5 small cell carcinoma (Ca), 17 epidermoid Ca, 12 adeno Ca, 6 undifferentiated large cell Ca] and 10 benign lesions underwent technetium-99m (V) dimercaptosuccinic acid [99m-(V)DMSA] scans to evaluate the usefulness of 99mTc-(V)DMSA in the detection of lung Ca with different cell types and benign lesions. Only 43% (17/40) of the malignancies in the lungs were detected by 99mTc-(V)DMSA, including 29% (5/17) epidermoid Ca, 50% (6/12) adeno Ca and 17% (1/6) undifferentiated large cell Ca of the lungs. However, all 5 cases of small cell Ca and 11 cases combined with bone metastasis were revealed by 99mTc-(V)DMSA. In addition, 3 of the 10 benign lesions (2 organizing pneumonias, 1 benign tumor) presented with an uptake of 99mTc-(V)DMSA. The diagnostic sensitivity, specificity and accuracy were 43%, 70% and 48%, respectively, in differentiating malignant from benign lesions for the single solid mass in the lungs. In conclusion, 99mTc-(V)DMSA is of little or no use in the differentiation of lung Ca from single solid masses in the lungs.

Intravenous dipyridamole technetium-99m MMI myocardial perfusion scintigraphy for detection of coronary artery disease

To evaluate the efficacy of stress technetium-99m MMI (N-2-methoxy-2-methyl propyl isonitrile) myocardial perfusion scintigraphy (Tc-99m MMI) using intravenous dipyridamole for detection of coronary artery disease (CAD), we collected 66 cases (53 men, 13 women, aged 40-79 years old) between Sept. 1990 and Oct. 1991. The cases were divided into two groups: group I involving 44 patients received coronary arteriography (CAG) examination without previous percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass graft (CABG); group II embracing 22 patients received no CAG examination but all were suffering from old myocardial infarction (MI) evidenced by history and electrocardiography (ECG). All cases underwent Tc-99m MMI planar and single photon emission computed tomography (SPECT) both on intravenous dipyridamole stress and separate day rest tests. Of the 44 group I patients receiving both Tc-99m MMI and CAG, 35 (79.5%) were positive and 7 (16%) were negative by both tests and another 2 (4.5%) were positive by CAG only. Of those positive by both tests, 21 (60%) suffered from identical coronary arterial involvement, including 13 one-vessel disease, 5 double-vessel disease and 3 triple-vessel disease. Of group II patients, 14 suffered from old inferior wall (IW) MI, 6 from old anterior or anteroseptal wall (AW) MI, 1 from old lateral wall (LW) MI and another 1 from combined old anterior and lateral wall (ALW) MI by ECG. Of the 14 patients with IWMI by ECG, all suffered from right coronary artery (RCA) disease but 7 (50%) of them from multivessel disease (MVD) by Tc-99m MMI. 5 of the 6 patients with AWMI by ECG suffered from left anterior descending coronary artery (LAD) disease, but 3 of them from MVD by Tc-99m MMI. Both patients with LWMI and ALWMI by ECG suffered from triple-vessel disease by Tc-99m MMI. The sensitivity of Tc-99m MMI in detecting CAD in group I was 95%, the specificity was 100%. The sensitivity for detection of individual coronary artery disease in LAD, left circumflex coronary artery (LCX) and RCA was 96%, 45% and 89% in this order and the respective specificity was 94%, 100% and 88%. In group II the sensitivity was 95%. The overall sensitivity of intravenous dipyridamole Tc-99m MMI for detection of CAD in groups I and II was 95%; specificity was 100% and accuracy was 95%. In conclusion, stress Tc-99m MMI using intravenous dipyridamole is a valuable method for evaluation and detection of CAD.

[Pacemaker syndrome and retrograde ventriculoatrial conduction]

19 cases of pacemaker syndrome were observed in 121 patients implanted with VVI pacemakers. The main manifestations of pacemaker syndrome were dizziness, lightheadedness, fatigue, hypotension and congestive cardiac failure after permanent ventricular pacing. The incidence of pacemaker syndrome was 20% in patients with sick sinus syndrome and 13.2% with A-V block. Pacemaker ECG showed retrograde ventriculoatrial conduction in 25 of 121 cases. Among these patients, 14 (56%) had pacemaker syndrome, while only 5 of 96 cases without ventriculoatrial conduction had this syndrome, so the incidence of the two groups were quite different, P less than 0.0001. The frequency of ventriculoatrial conduction in patients with sick sinus syndrome was higher than in patients with A-V block (16/45 vs 9/76, P less than 0.05). The electrophysiologic study were performed in 17 cases before PM implantation. 3 cases had 170-190 ms ventriculoatrial 1:1 conduction. Retrograde ventriculoatrial conduction in pacemaker ECG were present during ventricular pacing in all of them.