Reverse redistribution of technetium-99m-tetrofosmin after acute coronary revascularization in patients with myocardial infarction

This study qualified the severity and localization of reverse redistribution of technetium-99 m (Tc)-tetrofosmin rest imaging. Both Tc-tetrofosmin and thallium-201 (Tl) rest imaging with early images and delayed images were obtained in the subacute phase of myocardial infarction in 21 patients with first anterior myocardial infarction and with successful transluminal angioplasty (including stenting). Relative myocardial uptake (%uptake), degree of reverse redistribution (%), and washout rate (%) were evaluated quantitatively in 6 left ventricular segments (inferoseptal, anteroseptal, anterior, anterolateral, lateral, inferolateral and inferior) by circumferential profile analysis. The percentage reverse redistribution in the infarct area was larger in Tc-tetrofosmin imaging than in Tl imaging (p = 0.013). Reverse redistribution was most prominent in the anterior wall (anterior > anteroseptal > inferoseptal, p = 0.020). This suggests that infradiaphragmatic scatter is unlikely as the mechanism of reverse redistribution. The washout rate of Tc-tetrofosmin in the infarct area (reverse redistribution area) was higher than that in the normal area (non-reverse redistribution area), and was also higher than the washout rate of Tl imaging in the infarct area. The %uptake of delayed images in the infarct area was larger in Tc-tetrofosmin than that in Tl imaging, whereas %uptake of early images did not differ. The percentage reverse redistribution did not correlate with the degree of collateral circulation and the residual stenosis. In conclusion, reverse redistribution of Tc-tetrofosmin was more prominent in the infarct area, and this was due to the relatively lower uptake of reverse redistribution of Tc-tetrofosmin than delayed Tl images.     

The Association between Diet Quality and Health Status in Mobile Food Pantry Users in Northeastern Connecticut

Low-income Americans tend to have poor diet quality and disease prevalence overall. Mobile food pantries aim to improve these outcomes, and have rarely been studied. This cross-sectional study aimed to evaluate the association between diet quality and health status in mobile food pantry users. Data were collected from two mobile food pantry sites in Northeastern Connecticut (n = 83). Sociodemographic food security and diet quality data were collected. Overall, diet quality was low among all participants with intakes of fruits, vegetables, and whole grains of concern. Participant adherence to the 2020–2025 US Dietary Guidelines were low, with no participants meeting recommendations for whole grains. Obesity, diabetes, and hypertension prevalence in this population exceeded national averages. After adjusting for covariates, hypertension was associated with higher dairy and added sugar intake, as well as a greater intake of added sugar from sugar-sweetened beverages (p < 0.05). Although results were not statistically significant, participants with obesity, diabetes, and hypertension showed a trend of having lower adherence to the guidelines than those without these chronic diseases. Questions assessing participant interest in changing their diets were also posed, indicating overall high interest in learning about current diet quality and weight improvement.     

Changes in tissue-plasminogen activator mRNA expression following cortical ablation in the rat brain

Tissue plasminogen activator (tPA) has been used to treat acute thrombotic lesions. Roles other than the activation of fibrinolytic pathways have been suggested for tPA in the mature brain. We used the in situ hybridization technique to investigate the changes in tPA mRNA expression within the brain after cortical ablation. We found that expression of tPA mRNA started to increase diffusely in the cortex ipsilateral to the injury 6 h after ablation. This increase had become prominent 24 h after ablation. On d 5, the expression of tPA mRNA had returned to that of the control animals except for the area near the injury. We also found that administration of MK-801 before injury suppressed the increase of tPA mRNA in the ipsilateral cortex. These results suggest that the increase in tPA mRNA is likely to be mediated via activation of NMDA receptors.     

Dendritic cell appearance and differentiation during early and late stages of rat stomach carcinogenesis.

Dendritic cell appearance and differentiation during early and late stages of rat stomach carcinogenesis were studied in the pyloric mucosa. Young male rats were given drinking water with or without N-methyl-N'-nitro-N-nitrosoguanidine (MNNG; 100 mg/liter) for 14 days. Use of competitive RT-PCR and northern blotting showed that MNNG exposure induced 3- to 4-fold greater expression of the genes for integrin beta7 and integrin alphaE2 (identical with antigen OX-62, a dendritic cell marker), as well as three cytokines, IL-4, GM-CSF and TNFalpha, in the stomach pyloric mucosa of resistant Buffalo rats compared to sensitive ACI rats. These genes were minimally expressed in control animals. The results confirm the appearance of dendritic cells in the target pyloric mucosa and suggest the possibility that dendritic cell differentiation and maturation are induced by various cytokines, at least in Buffalo rats. Competitive RT-PCR showed expression of integrin alphaE2 and beta7, MHC class II-associated invariant chain (Ii), MHC class II, B7-1, CD28, GM-CSF and TNFalpha genes in all 12 examined stomach adenocarcinomas and adenomas induced in male Lewis and WKY rats with 30 weeks' MNNG exposure, suggesting the presence of dendritic cells in tumors. OX-62 staining and western blotting for OX-62 also confirmed the presence of dendritic cells in tumors. However, the population of dendritic cells in tumors was less than that in the pyloric mucosa after 14 days' MNNG exposure. The present results suggest that immune defense involving dendritic cells is marshaled from the very early initiation stage during rat stomach cancer development, but is downgraded in developed tumors.     

Neuroprotective effect of a neurotoxin, 3-nitropropionic acid, against hypoxic damage to the gerbil hippocampus: neuroprotection after the onset of hypoxic depolarization]

Ischemic/hypoxic tolerance induced by a subtoxic dose of neurotoxin, 3-nitropropionic acid(3-NPA), was recently reported as "chemical preconditioning". We previously showed that the neuroprotective effect by chemical preconditioning with 3-NPA was induced by prolonging the delay to hypoxic depolarization (HD) via activating adenosine receptors. In this study, we electrophysiologically assessed whether the protective effect of chemical preconditioning was potent after the onset of HD. An in vitro hippocampal slice model from adult gerbils was used to study the delay to HD during hypoxia and the recovery of synaptic responses after hypoxia. Hypoxia was sustained until a fixed period(8 min) following HD. These responses were examined in control slices and slices pretreated with subtoxic dose of 3-NPA(4 mg/kg) intraperitoneally at 3 hours prior to slice preparation. The delay to hypoxic depolarization in 3-NPA treated slices was significantly prolonged(p < 0.05). The field excitatory postsynaptic potential recovery after a fixed period of hypoxia under HD was also significantly improved in the 3-NPA treated group(48.6 +/- 23.8%) compared with the control group(29.2 +/- 12.2%) (p < 0.05). This finding indicates that chemical preconditioning with 3-NPA induces the neuroprotective effect against hypoxic damage after as well as before the onset of HD to the hippocampus.     

Surgery for intractable epilepsy in children: pre- and perioperative evaluations with special reference to dipole tracing method estimated from interictal spike

Methods of preoperative and perioperative evaluation methods for surgical treatment of intractable epilepsy in children are described. Among non-invasive diagnostic methods, EEG-video monitoring is the most fundamental. Amygdalohippocampal volume measurement by MR was useful for the differential diagnosis of mesial temporal lobe epilepsy (TLE) from lateral TLE and generalized epilepsy. The dipole tracing method with a realistic head model was useful for identification of epileptic foci from the interictal spikes of scalp EEG, when an abnormal electric source was estimated as an equivalent current dipole (ECD) in the brain of patients with organic lesion and TLE. ECD concentration ratio ranged from 70 to 90% within 20 mm around the lesion. After lesionectomy seizures disappeared in every patient. The mean distance between the centers of the ECD and epileptic focus (identified by subdural electrode recording) was 14 mm (range: 8 to 18 mm). ECDs of mesial TLE were located in the temporal base rather than mesial temporal lobe, whereas those of lateral TLE in the lateral cortex precisely. In unilateral, intermediate and bilateral TLE, 76%, 52% and 36% of ECDs were localized in the ictal onset zone respectively (p = 0.007). Electrical cortical stimulation with chronically placed intracranial electrodes was used to accurately identify eloquent areas to avoid postsurgical complications. Immediately after operation, 10 to 20% of patients showed better or deteriorated results in neuropsychological examinations, which recovered in all patients after one year. Postoperative seizures were absent in three fourths of patients. Further efforts are needed to obtain better seizure control in future.     

Radiosurgery-induced brain tumor. Case report

The authors describe a case of glioblastoma multiforme (GBM) associated with previous gamma knife radiosurgery for a cerebral arteriovenous malformation (AVM). A 14-year-old boy had undergone radiosurgery for an AVM, which was performed using a 201-source 60Co gamma knife system at another institution. The maximum and margin radiation doses used in the procedure were 40 and 20 Gy, respectively. One year after radiosurgery, the patient noticed onset of mild left hemiparesis due to radiation necrosis. Six and one-half years after radiosurgery, at the age of 20 years, the patient experienced an attack of generalized tonic-clonic seizure. Magnetic resonance (MR) imaging revealed the existence of a brain tumor in the right parietal lobe. The patient underwent an operation and the histological diagnosis of the lesion was GBM. Ten months following the operation, that is, 99 months postradiosurgery, this patient died. To the best of the authors' knowledge, this is the first reported case of a neoplasm induced by radiosurgery for an AVM and the second case in which it occurred following radiosurgery for intracranial disease.     

Purification and Properties of the γ-Protein Specified by Bacteriophage λ: An Inhibitor of the Host RecBC Recombination Enzyme

Previous experiments have indicated that the gam gene of bacteriophage lambda is responsible for an inhibition of the RecBC DNase-an enzyme that is essential for the major host pathway of genetic recombination. We report here experiments that define the inhibitor as the protein product of the gam gene ("gamma-protein") and that characterize the inhibition reaction with highly purified preparations of gamma-protein and RecBC DNase. Genetic characterization was performed with partially purified fractions prepared from cells infected with various lambda mutants. An activity that inhibits RecBC DNase was absent in extracts prepared after infection by phage that carry nonsense or deletion mutations in the gam gene; this activity was highly thermolabile in an extract prepared after infection by phage that carry a temperature-sensitive mutation in the gam gene. For biochemical characterization, the gamma-protein has been purified more than 800-fold. This highly purified preparation inhibited all of the known catalytic activities associated with the RecBC enzyme, but exhibited no detectable DNase or ATPase activities by itself. These findings are discussed in terms of their implications for regulation of genetic recombination and bacteriophage lambda development.     

Postoperative hyperperfusion associated with steal phenomenon caused by a small arteriovenous malformation

A 41-year-old woman presented with a small occipital arteriovenous malformation (AVM) manifesting as headache. Cerebral angiography showed an AVM in the right occipital lobe fed by the right temporooccipital artery and draining into the superior sagittal sinus and right transverse sinus. Single photon emission computed tomography showed the steal phenomenon in the ipsilateral temporal cortex fed by the main feeding artery preoperatively, and hyperperfusion in the same cortex after removal of the AVM. Postoperative systolic blood pressure was maintained between 100 and 120 mmHg to avoid disastrous hemorrhagic complications. Cerebral blood flow evaluation before and after surgery is important to avoid postoperative disastrous complications even in patients with small AVM.