Erythema-multiforme-like eruption from antibiotics of 3 different groups.
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Anti-Bacterial Agents↗
Biomedical subjects
E Fernandez
Publications and source records attributed to E Fernandez.
Superior cervical ganglion regenerating axons through peripheral nerve grafts and reversal of behavioral deficits in hemiparkinsonian rats.
The superior cervical ganglion (SCG) has been grafted to the brain of adult rats in an attempt to reverse the parkinsonian syndrome that follows destruction of central dopamine systems. However, the main limitation to this approach is the massive cell death that occurs in the grafted SCG after direct transplantation into the brain. In adult rats, 6-hydroxydopamine (6-OHDA) was stereotactically injected into the right substantia nigra (SN). One month later, dopamine denervation was assessed using the apomorphine-induced rotational test. In rats with a positive test, an autologous peripheral nerve (PN) graft was tunneled from the right cervical region to the ipsilateral parietal cortex. One end of PN graft was sutured to the transected postganglionic branch of the SCG and the other end was inserted into a surgically created cortical cavity. The apomorphine test was repeated at 3 days and again at 1, 3, and 5 months after surgery. The brain, SCG, and PN graft were studied under light and electron microscopy and with the tyrosine hydroxylase immunohistochemical and horseradish peroxidase tracing methods. Three days after grafting, there were no significant differences on the apomorphine test as compared to the preoperative test. Conversely, 1,3, and 5 months after grafting, the number of rotations was reduced by 69% (+/-20.2), 66.6% (+/-17.1), and 72.5% (+/-11.3), respectively. Control rats that received a free PN graft to the brain and underwent section of the postganglionic branch of the SCG did not show significant changes on the apomorphine test after surgery. Histological examination revealed that the PN graft was mostly reinnervated by amyelinic axons of small caliber. Approximately 40% of the SCG neuronal population that normally projects to the postganglionic branch survived axotomy and regenerated the transected axons into the PN graft. Axons arising from the SCG elongated the whole length of the graft, crossed the graft-brain interface and extended into brain regions adjacent to the denervated striatum up to 2037 micrometer from the graft insertion site. This work shows that the ingrowth of catecholamine-regenerating axons from the SCG to dopamine-depleted brain parenchyma significantly reduces behavioral abnormalities in hemiparkinsonian rats. This effect cannot be ascribed either to the brain cavitation or to the PN tissue placement in the brain.
Animals↗
Surgical treatment of clival chordomas: the transsphenoidal approach revisited.
This is a report of 12 cases of clival chordomas that were surgically treated at the Catholic University Medical School, Rome, Italy, over a 7-year period. The study emphasizes the role of the transsphenoidal approach. The study group included seven men and five women whose ages ranged from 26 to 80 years (mean 49.8 years). Diplopia was the most common presenting symptom (eight cases). The tumor involved the upper and middle clivus in five cases, the middle clivus in five, and the lower clivus in two cases. One patient developed spinal metastasis. On histological examination, eight cases proved to be typical chordomas, three cases had a chondroid component, and one case of chordoma had atypical features. Immunohistological staining for vimentin and epithelial membrane antigen was positive in all cases. Follow-up periods ranged from 14 to 86 months (mean 40.2 months). The primary treatment consisted of surgery. Ten patients with chordomas of the upper and middle clivus underwent a total of 13 transsphenoidal procedures. Total tumor removal was achieved in seven cases, subtotal removal in two, and partial removal in one case. In the two cases of lower clival chordomas, total removal was accomplished in one and partial removal in the other. After total removal, no recurrence was noted at 14 to 86 months (mean 37.5 months). In the cases undergoing operation via a transsphenoidal approach, there was zero morbidity and one cerebrospinal fluid fistula that resolved without surgery. The tumor recurred in two patients after subtotal and partial removal, respectively. The authors opted to reoperate in cases of recurrence. Postoperative radiotherapy was administered in only two cases in which further surgery was not indicated because of medical reasons or because such a procedure was contrary to the patient's wishes. When mortality and morbidity rates of this group are compared to those of chordoma patients who were treated with extensive skull-base surgery, the results prompt a reappraisal of the transsphenoidal approach in the treatment of clival chordomas.
Adult↗
Attributable risks for pancreatic cancer in northern Italy.
The proportions of pancreatic cancer cases attributable (or attributable risks) to tobacco smoking, high consumption of meat, low consumption of fruit, family history of pancreatic cancer, and previous history of pancreatitis were computed by using data from a case-control study conducted in Northern Italy. Between 1983 and 1992 a total of 362 incident, histologically confirmed exocrine pancreatic cancer cases and 1408 controls admitted to the same network of hospitals for acute, non-neoplastic, nondigestive, nonhormone-related disorders, were interviewed. The ARs were 14% for tobacco smoking, 14% for high consumption of meat, and 12% for low consumption of fruit. Overall, these factors explained 23% of pancreatic cancer in the population. The proportion of cases attributable to tobacco smoking was greater among males (20%) as compared with females (5%), as well as were the attributable risks for a diet with a high consumption of meat and a low consumption of fruit (25% in males versus 18% in females). In conclusion, almost one-fourth of pancreatic cancer cases in this population were explainable in terms of a few identified simple risk factors. Smoking cessation and a healthier eating pattern would prevent approximately 1500 pancreatic cancer deaths in Italy every year. In the absence of effective early detection and therapeutic tools for the disease, the intervention on these factors would, thus, have a relevant impact in reducing pancreatic cancer mortality.
Adult↗
Diet diversity and the risk of colorectal cancer in northern Italy.
The relationship between diet diversity (i.e., variety in food intake computed as the total number of foods consumed at least once per week) and the risk of colorectal cancer was investigated using data from a hospital-based, case-control study carried out between 1985 and 1992 in Northern Italy. Subjects were patients with histologically confirmed incident cancers of the colon (n = 828) and rectum (n = 498) and 2024 controls admitted for acute, nonneoplastic, non-digestive tract conditions. A significant inverse association (multivariate relative risk, 0.7) for the highest (more diverse diet) versus the lowest quartile of total diet diversity was observed, together with a significant trend in risk. A similar risk was observed for diversity within vegetables (RR, 0.6, highest versus lowers quartile), but no consistent association was found for fruit, meat and fish, and "other food" diversity. A similar pattern was observed when colon and rectal cancers were considered separately or across separate strata of sex and age. Diet diversity is related to a moderately decreased risk of colorectal cancer. These results add epidemiological support to the dietary guidelines recommending a more varied diet, and, if confirmed by other studies, would have considerable public health implications.
Adult↗
Menstrual and reproductive factors and pancreatic cancer risk in women.
To investigate possible correlates of the systematically higher pancreatic cancer rates in males than in females, the role of menstrual, reproductive and hormonal factors in females have been assessed using data from a case-control study conducted in Northern Italy. Cases were 133 women with histologically confirmed incident cancer of the pancreas, and controls were 377 women in hospital for acute, non-neoplastic, non-digestive-tract disorders. After allowance for age, education, area of residence and smoking habit, an increased risk of pancreatic cancer was observed in women with early menarche (< or = 13 years) (OR = 1.9; 95% CI: 1.0-3.6), but no significant association was observed with age at menopause or length of fertile life. Parous women were at reduced risk as compared to nulliparous women (OR = 0.7), although the trend in risk with number of births was not significant. No association with spontaneous or induced abortions was observed. Pancreatic cancer risk was inversely related to early age at first birth (first birth < 25 versus nulliparae: OR = 0.5; 95% CI: 0.3-0.9; p-value for trend < 0.01) and to age at last birth (last birth < 25 versus nulliparae: OR = 0.3; 95% CI: 0.1-0.8; p-value for trend < 0.05). Ever-users of estrogen replacement therapy showed a non-significantly increased risk (OR = 2.2). Although no clear pattern of association is evident, the present results are in agreement with previous epidemiological observations and experimental research indicating that hormonal (menstrual and reproductive) factors could explain part of the male-to-female differential in incidence and mortality from pancreatic cancer.
Adult↗
Chronic arterial hypertension as unique symptom of brainstem astrocytoma.
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Adult↗
Response-reinforcement relationships in chronic pain syndrome: applicability of Herrnstein's law.
The quantitative relationship between chronic pain behavior and reinforcement has been generally found to be positive. Herrnstein's statement of the law of effect adds a qualification: it predicts that response rate varies hyperbolically with contingent reinforcement, and that response rate is also negatively related to extraneous reinforcement. The present study is an original investigation of the first of these assertions with regard to the naturally occurring behaviors in chronic pain syndrome. It was found that the stereotypic pain behaviors of 12 chronic pain patients were hyperbolically rather than proportionally related to contingent reinforcement from their significant others. Likewise, healthy behaviors in the same group were a hyperbolic function of contingent reinforcement. Estimates of extraneous reinforcement were also obtained for each category of behaviors. As a group, the subjects showed an inverse relationship between pain behaviors and healthy behaviors, consistent with previous research in the pain area. The present findings add generality to Herrnstein's matching law which serves as a descriptive model of target behaviors in chronic pain patients. The findings also have prescriptive implications for the modification of behavior among chronic pain sufferers.
Adult↗
Determination of fractal dimension of physiologically characterized neurons in two and three dimensions.
Although there is a growing interest in the application of fractal analysis in neurobiology, questions about the methodology have restricted its wider application. In this report we discuss some of the underlying principles for fractal analysis, we propose the cumulative-mass method as a standard method and we extend the applicability of fractal analysis to both 2 and 3 dimensions. We have examined the relationship between the method of log-log Sholl analysis and fractal analysis and have found that they correlate well. Measurements of physiologically characterized retinal ganglion cells indicate that different cell types can have significantly different fractal dimensions. Such differences may allow the correlation of the physiological type of a neuron with its morphological fractal dimension.
Animals↗
Pool tests for detection of hepatitis C virus infection.
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Blood Donors↗
Muscarinic receptor subtypes in the bisected vas deferens of the rat.
1. The nature of muscarinic receptor subtypes in the isolated prostatic and epididymal segments of the vas deferens of the rat were studied. 2. Presynaptic receptors were characterized in segments under neurogenic transmural stimulation; postsynaptic receptors in segments without stimulation. 3. The present work suggests that the potency of ACh required to activate muscarinic receptors is higher in the prostatic than in the epididymal segment. 4. McN-A-343 was only able to induce dose-dependent contractions in the prostatic segment. 5. The pA2 value for 4-DAMP suggests that in the prostatic segment the postsynaptical ACh receptors seem to be pharmacologically similar to the ACh-M3 subtype. 6. Antagonism of the presynaptic ACh receptor subtype by pirenzepine supports the evidence that these receptors belong to the ACh-M1 subtype.
(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethy↗
Inhibitory effect of Escherichia coli endotoxin on skeletal muscle contractility.
OBJECTIVE: Endotoxemia in rabbits is associated with decreases in oxygen transport, tissue hypoxia, metabolic acidosis, and impaired oxygen extraction. In this study, we tested the hypothesis that endotoxin also inhibits skeletal muscle contractility directly. DESIGN: Randomized animal study. SETTING: Accredited animal research facility. SUBJECTS: New Zealand white rabbits of either sex, weighing 2.55 +/- 0.20 kg. INTERVENTIONS: We compared two groups of rabbits (n = 10 each) undergoing continuous electrical stimulation of the left hindlimb (maximal isometric twitch contraction at 0.25 Hz). One group (septic) was given an intravenous infusion of Escherichia coli endotoxin. The control group was subjected to decreases in cardiac output by inflating a balloon placed in the right ventricle. MEASUREMENTS AND MAIN RESULTS: Endotoxin or balloon inflation resulted in comparable decreases in cardiac output (49% and 53%, respectively). Hindlimb oxygen transport decreased to similar values for both groups (4.9 +/- 0.3 and 4.2 +/- 0.5 mL/min/kg, respectively). Systemic oxygen extraction ratio was greater in the control group (0.72 +/- 0.03) than in the septic group (0.55 +/- 0.04; p < .05). There were no differences in hindlimb oxygen extraction ratio. Decreases in hindlimb forces were greater in the septic group (42 +/- 4%) than in the control group (18 +/- 3%, p < .01). Force frequency curves obtained at the beginning and the end of the experiment showed greater fatigue in the septic group. CONCLUSIONS: The intravenous infusion of Escherichia coli endotoxin produces a direct inhibitory effect on skeletal muscle contractility in rabbits. This phenomenon is independent of decreases in oxygen transport and blood pH. Our data support the notion of a direct cellular effect of endotoxin, or of an associated cytokine, on skeletal muscle contractility. The mechanism responsible for this phenomenon is unknown.
Animals↗
Pancreatitis and the risk of pancreatic cancer.
To offer quantitative evidence on the association between pancreatitis and pancreatic cancer, we analyzed data from a hospital-based case-control study conducted in northern Italy between 1983 and 1992, including a total of 362 incident cases of histologically confirmed pancreatic cancer and 1,408 controls admitted to hospital for acute, nonneoplastic, nondigestive tract disorders. Information was obtained using a structured questionnaire on sociodemographic characteristics and lifestyle habits (including tobacco and alcohol consumption) and a problem-oriented medical history, which included history of pancreatitis and age at its first diagnosis. Pancreatitis was reported by 24 (6.6%) cases and 18 (1.3%) controls, yielding an age- and sex-adjusted relative risk (RR) of 5.7 (95% confidence interval, 2.9-11.4). The risk of pancreatic cancer was appreciably higher 5 or more years after diagnosis of pancreatitis (RR = 6.9) than in the first 4 years (RR = 2.1), and in subjects below age 60 (RR = 8.3) than in elderly ones (RR = 2.6), but similar in males and females. The time-risk relationship is strongly indicative of a real relationship between pancreatitis and pancreatic cancer. After allowing for tobacco and alcohol, besides area of residence and education, the association between pancreatitis and pancreatic cancer appeared to be partly explained by such covariates (RR = 3.9); however, this may represent some degree of overadjustment if, for instance, alcohol is causally linked to pancreatitis, which, in turn, is causally related to pancreatic cancer. In terms of population attributable risk, pancreatitis would explain approximately 5% of pancreatic cancer cases.
Adult↗
Alpha 1-adrenoceptor reagents. Synthesis of some 5,6,11,11a-tetrahydro-1H-imidazo[1',5':1,6]pyrido and 5,6,11,11b-tetrahydro-1H-imidazo[1',5':1,2]pyrido[3,4-b]indole-1,3(2H) -diones.
Several 2-substituted 5,6,11,11a-tetrahydro-1H-imidazo[1',5':1,6]pyrido (1) and 5,6,11,11b-tetrahydro-1H-imidazo [1',5':1,2]pyrido[3,4-b]indole,3(2H)-diones (2) were synthesized and studied by 2D-NMR spectroscopy and difference nuclear Overhauser effect experiments. All the compounds were evaluated for in vitro alpha(1) adrenoceptor affinity by radioligand receptor binding assays. The most active derivative in displacement of [3H]prazosin from rat cortical membranes was 1b (K(i) = 219 nM). At 1 microM concentration, compounds 1 and 2 had no effect on the benzodiazepine or 5-HT(1A) receptor. The biological activity profile of 1b makes it a possible lead compound for the design of new selective alpha1 adrenoceptor ligands.
Animals↗
Thallium poisoning presenting with abdominal colic, paresthesia, and irritability.
A case of acute thallium poisoning presenting with sudden abdominal pain, paraesthesiae and irritability is described. The peripheral nervous system was later affected along with loss of hair and the development of streaks (Mee's lines) on the nails of the hands and feet. The diagnosis was established by thallium assays of blood and urine. Thallium was undetectable in the blood by day 70. The manifestations cleared in six months with symptomatic treatment only. We review the characteristics and differential diagnosis of thallium poisoning and stress the importance of a high index of clinical suspicion.
Adult↗
Quantitative, morphological, and somatotopic nuclear changes after facial nerve regeneration in adult rats: a possible challenge to the "no new neurons" dogma.
The anatomic reorganization of the subnucleus that controls the stylohyoid muscle (the stylohyoid subnucleus) within the brain stem facial nucleus was studied after regeneration of the facial nerve in adult rats. Horseradish peroxidase was injected into the right stylohyoid muscle 3 to 21 months after transection and repair of the right facial nerve at the level of the stylomastoid foramen. Position, number, and soma diameter of retrogradely horseradish peroxidase-labeled motoneurons were established, as well as the rostro-caudal extension of the stylohyoid subnucleus. In experimental rats, the stylohyoid subnucleus showed either an ipsilateral (50% of the rats) or a bilateral representation. In all of the experimental rats, the motoneurons composing the stylohyoid subnucleus had a more dispersed horizontal distribution pattern when compared with controls. More than 80% of the motoneurons were located outside the borders of the normal stylohyoid subnucleus, either ventrally or, especially in the rostral sections, dorsally closer to the floor of the fourth ventricle. The mean rostro-caudal length of the stylohyoid subnucleus was 2028.6 +/- 152.7 microns. The mean motoneuron number was 481.4 +/- 109.5 (2.20-fold greater than control values), and the motoneuron diameter distribution ranged from 7 to 43 microns. This study demonstrates that after regeneration of the facial nerve in adult rats, major changes occur in both the location and number of motoneurons that make up the stylohyoid subnucleus.(ABSTRACT TRUNCATED AT 250 WORDS)
Age Factors↗
Effects of levo-acetylcarnitine on second motoneuron survival after axotomy.
Little is known about factors that regulate the survival of cranial motoneurons which project to peripheral targets. Various neurotrophic factors of central and peripheral origin have been isolated. In this study, we examined thirteen newborn Wistar rats to determine the effects of acetyl-L-carnitine treatment on the survival of motoneurons within the facial nucleus after transection of the facial nerve. Acetyl-L-carnitine was administered for 7 days in seven rats after nerve transection, while saline solution was injected in 6 rats used as controls. Both the motoneuron number and the motoneuron diameter were significantly higher in the facial nucleus of the rats treated with acetyl-L-carnitine than in the facial nucleus of the control rats. The results obtained suggest that acetyl-L-carnitine can rescue a substantial number of facial motoneurons from axotomy-induced cell death. Compared to neurotrophic factors, because of its simple molecular structure, acetyl-L-carnitine permits a safe oral and parenteral administration. It is suggested that acetyl-L-carnitine could be considered for use as a therapeutic agent in neurodegenerative disorders.
Acetylcarnitine↗
Complexity and scaling properties of amacrine, ganglion, horizontal, and bipolar cells in the turtle retina.
In the present study we have evaluated the complexity and scaling properties of the morphology of retinal neurons using fractal dimension as a quantitative parameter. We examined a large number of cells from Pseudemys scripta and Mauremys caspica turtles that had been labeled using Golgi-impregnation techniques, intracellular injection of Lucifer Yellow followed by photooxidation, intracellular injection of rhodamine conjugated horseradish peroxidase, or intracellular injection of Lucifer Yellow or horseradish peroxidase alone. The fractal dimensions of two-dimensional projections of the cells were calculated using a box counting method. Discriminant analysis revealed fractal dimension to be a significant classification parameter among several other parameters typically used for placing turtle retinal neurons in different cell classes. The fractal dimension of amacrine cells was significantly correlated with dendritic field diameters, while the fractal dimensions of ganglion cells did not vary with dendritic field span. There were no significant differences between the same cell types in two different turtle species, or between the same types of neurons in the same species after labeling with different techniques. The application of fractal dimension, as a quantitative measure of complexity and scaling properties and as a classification criterion of neuronal types, appears to be useful and may have wide applicability to other parts of the central nervous system.
Animals↗