Biomedical subjects

E E Calore

Publications and source records attributed to E E Calore.

At least 37 records · Page 2Linked to original sources

PubMed1999

Sarcoplasmic lipase and non-specific esterase inhibition in myofibers of rats intoxicated with the organophosphate isofenphos.

The expression of sarcoplasmic esterases, lipases as well as the lipid content in the myofibers of the diaphragm of rats intoxicated with the organophosphate isofenphos was studied. Lipid accumulation was documented at light, electron microsopic and by morphometric studies. The distribution of these lipid droplets was irregular and abundant in myofibers with numerous mitochondria (predominantly oxidative fibers). Histochemical inhibition of sarcoplasmic esterases and lipases was observed in the intoxicated animals. This sarcoplasmic inhibition of esterases occurs roughly in parallel to the inhibition of plasma cholinesterase activity. The inhibition of sarcoplasmic lipases may explain, at least partially, the accumulation of lipids. This inhibition probably makes difficult the use of lipids as fuel, especially in the oxidative fibers. In contrast to the small amount of muscle necrosis, (1.30+/-0.745), metabolic muscle impairment was intense and extensive, i.e., decreased activities of esterases and lipases in the sarcoplasm, that should contribute to muscle weakness. Therefore, because segmental necrosis was most prominent in oxidative fibers (and these fibers use lipids as the principal fuel and contain the greater amount of lipases in the sarcoplasm), it is possible that inhibition of activity of lipases is responsible for the segmental necrosis. Although the exact role of these metabolic changes is not known, it is possible that they contribute not only to the induction and evolution of muscle cell necrosis but also to the muscle weakness and clinical impairment of animals and humans in the acute intoxication by these compounds.

Animals↗

PubMed1999

The lysosomal enzymes acid phosphatase and cathepsin D in rats intoxicated with Senna occidentalis seeds.

Chronic administration of Senna occidentalis seeds induces an experimental toxic myopathy characterized by skeletal muscle fibers atrophy, decrease in histochemical activity of cytochrome oxidase, and increase of the acid phosphatase activity in muscle fibres at the light microscopic level. The mechanisms that lead to the increase of this lysosomal enzyme activity are not known and could be related to other biochemical disturbs than the mitochondrial function impairment. The main aim of the present study is to localize the acid phosphatase activity using a cytochemical method at transmission electron microscopy level and to quantify cathepsin D in muscle of rats chronically intoxicated with Senna occidentalis seeds by immunoblotting. Acid phosphatase was observed in lysosomes and over profiles of some organelles apparently not involved by lysosomal membrane. In addition immunoblotting demonstrated a decrease in the content of the precursor and of the mature form of cathepsin D in samples of muscles and liver of intoxicated animals. We concluded that there is a selective increase in acid phosphatase activity in muscle--and maybe in other tissues--of animals intoxicated with Senna occidentalis, that can be related to the skeletal muscle atrophy and the intense decrease in weight gain of these animals. Further studies should be performed to establish the mechanisms of selectivity in increase of lysosomal enzymes in different situations and pathological states.

Acid Phosphatase↗

PubMed1998

Squamous intraepithelial lesions in cervical smears of human immunodeficiency virus-seropositive adolescents.

Various authors have reported a high rate of human papillomavirus (HPV) infection and HPV-related neoplasias in human immunodeficiency virus (HIV)-seropositive women. On the other hand, young women are most susceptible to cervical infection because of immaturity of the cervix, as it appears that HPV has more access to the basal cells of the differentiating epithelium. The purpose of the present work was to study cervical smears of 82 adolescent HIV-seropositive women (13-21 years of age) to search for cytological evidence of cervical intraepithelial neoplasias. Twenty-one cases showed characteristic features of HPV infection and squamous intraepithelial lesions (SIL; 25.6%). Sixteen cases aged from 17 to 21 years (mean age 19.5 years) had low-grade SIL (LSIL; 19.5%) and five cases aged from 18 to 21 years (mean age 20.2 years) had high-grade SIL (HSIL; 6.1%). There was no significant difference between the mean age of patients with LSIL and HSIL. Two cases had atypical squamous cells of undetermined significance (ASCUS). In the present work it was found that HIV-seropositive adolescents have a high risk for preneoplastic lesions of the cervix (25.6%) as well as a high incidence of more aggressive lesions (6.1% of HSIL) when compared to the general population of adolescents. As it can be assumed that, if the age of acquisition of the infection in both groups (in the general population and HIV-seropositive women) is the same, it is probable that HIV infection in adolescents not only increases the frequency of HPV infections but also facilitates the evolution to more aggressive preneoplastic lesions of the cervix due to HPV.

Adolescent↗

PubMed1998

Toxic peripheral neuropathy of chicks fed Senna occidentalis seeds.

Plants of the genus Senna (formerly Cassia) are poisonous to livestock and other laboratory animals, leading to a syndrome of a widespread muscle degeneration, incoordination, recumbence, and death. The main histologic lesion is necrosis of skeletal muscle fibers. Recently, a mitochondrial myopathy with ragged-red and cytochrome oxidase (COX)-negative muscle fibers was recognized in hens chronically intoxicated with parts of seeds of S. occidentalis. The purpose of the present work was to investigate if there was peripheral nerve involvement in the acute intoxication of chicks with S. occidentalis seeds. Teasing of individual fibers revealed signs of extensive axonal damage with myelin ovoids. Ultrathin sections confirmed the axonal damage. Axons were filled with membranes, some residual disorganized filaments, and enlarged mitochondria. In some instances the axon disappeared and there was secondary degeneration of the myelin sheath. The present work is the first description of the neurotoxic effect of S. occidentalis intoxication. Future work should attempt to determine the mechanisms involved in this neuropathy.

Animal Feed↗

PubMed1998

Non-isotopic in situ hybridization of HPV types in cervical intraepithelial lesions in patients with AIDS.

Human papilloma viruses (HPVs), particularly types 16 and 18 have a key role in the development of preneoplastic and neoplastic lesions of the uterine cervix. We studied, by non isotopic in situ hybridization using probes to HPV 6, 11, 16 and 18, cervical biopsies from AIDS patients with condilomata or cervical intraepithelial neoplasia. There were 32 biopsies which showed low-grade cervical intraepithelial neoplasia (Lo-CIN); 5 biopsies showed high-grade cervical intraepithelial neoplasia (Hi-CIN). Of 32 Lo-CIN biopsies, 18 (56.3%) were positive for HPV; 7 for HPV 6 and/or 11 (21.9%), 11 for HPV 16 and/or 18 (34.4%) and one for HPV 6 and 18. Of 5 Hi-CIN biopsies 3 were positive for HPV: one for HPV 6 and 2 for HPV 16 or 18. The total positivity was 56.8% (21/37). This result was similar to those obtained by various other authors studying the general population.

Acquired Immunodeficiency Syndrome↗

PubMed1998

Muscle atrophy induced in broiler chicks by parts of Senna occidentalis seeds.

Senna occidentalis (formerly Cassia occidentalis) is a common contaminant of agricultural commodities. It is toxic to cattle and poultry, reportedly being responsible for skeletal myodegeneration in these animals. All parts of the plant present toxicity, but the seeds are the most toxic. The toxin(s) responsible for the myodegeneration have not been definitively identified, nor is it known which part of the seeds is most toxic. Intoxication by this plant leads to weight loss with considerable economic repercussions. The effects of the whole seed and of parts of S. occidentalis seeds (1% in commercial feed) were compared on the pectoralis major muscle of broiler chicks intoxicated from birth until 22 days of life. There were severe clinical signals and reduced body weight in birds that received the external tegment of the seed, whereas no adverse effects were observed in birds that received the whole seed or other parts of the seed. Histological and morphometric studies showed an intense muscle fibre atrophy (both type 1 and type 2 fibres were affected) in the group that received 1% external tegment. This study may be the first step to identifying the substance(s) involved in this pathological process.

Animal Feed↗

PubMed1998

Protective effect of pralidoxime on muscle fiber necrosis induced by organophosphate compounds.

OBJECTIVE: To determine the protective effect of pralidoxime on muscle fiber necrosis induced by organophosphate acute intoxication in rats. DESIGN: Adult male Wistar rats were given oral organophosphate compounds dissolved in glycerol formal: dichlorvos, isofenphos, metamidophos, and diazinon. Half of the animals also received pralidoxime mesylate (20 mg/kg, intraperitoneal). Control animals received only the solvent. Twenty-four hours after treatment, the diaphragm muscle was collected for histological counts of necrotic muscle fibers in transverse sections. RESULTS: Metamidophos- and isofenphos-treated animals showed the highest percentage of necrotic muscle fibers: 1.66 +/- 1.112 and 1.34 +/- 0.320, respectively. Diazinon-treated animals had a lower percentage of necrotic fibers: 0.40 +/- 0.032 (p < 0.05) compared to the first 2 products, and dichlorvos-treated animals showed the smallest: 0.05 +/- 0.021 (p < 0.05) when compared to the other 3 products. Pralidoxime reduced necrotic fibers about 20 times in metamidophos-treated animals, 10 times in isofenphos-treated animals and 6 times in diazinon-treated animals. Pralidoxime administration did not increase plasma cholinesterase activity in any group, although symptoms were reduced. CONCLUSIONS: Oxime reduced diaphragmatic muscle necrosis in experimental organophosphate intoxication, despite little effect on plasma cholinesterase. Since respiratory insufficiency is an important cause of mortality and morbidity in organophosphate intoxications, early oxime administration may be particularly beneficial.

Acetylcholinesterase↗

PubMed1998

Nerve biopsy in patients with AIDS.

Patients with AIDS can present clinical involvement of the peripheral nervous system due to different causes. In the present work, it was studied the histopathological changes in sural nerve biopsy of fifteen patients with AIDS with this clinical involvement. It was observed the presence of a polyarteritis nodosa-like vasculitis of small arteries with fibrinoid necrosis in the sural nerve of 3 patients, one of them associated to polyradiculitis due to cytomegalovirus infection (CMV). Six patients presented mild axonal loss by light microscopy. Three other patients had a more important axonal neuropathy with myelin ovoids by teasing. By the electron microscopy in these patients were observed some fibers with axonal damage. The other three patients had normal sural nerves. We concluded that sural nerve biopsy may be important in peripheral neuropathies or myelo-radiculo-polyneuropathies in AIDS especially to search for nerve vasculitis, because it can change the therapeutic approach.

Acquired Immunodeficiency Syndrome↗

PubMed1997

Experimental mitochondrial myopathy induced by chronic intoxication by Senna occidentalis seeds.

Histochemical and electron microscopic studies of biceps femoris, pectoralis major and rectus femoris of chronically treated birds with seeds of the poisonous plant Senna occidentalis (0.2% external/internal tegment), were performed. The muscles had similar features of human mitochondrial myopathy as ragged-red fibers, cytochrome-oxidase negative fibers, and weak activity of the oxidative enzymes. Fibers with lipid storage were also present. Acid phosphatase activity in rare muscle fibers was also detected, and represents probably a secondary degenerative process. By electron microscopy, enlarged mitochondria with disrupted or excessively branched cristae were seen. The present study presents a new experimental model of mitochondrial myopathy that may be useful for the best knowledge of this group of diseases and for experimental trials of drugs that could reverse the mitochondrial impairment in the mitochondrial myopathies.

Animals↗

PubMed1997

Silver staining method for nucleolar organizer regions in cervical smears.

The distribution of nucleolar organizer regions (NORs) was studied in Papanicolaou preparations of cervical smears in order to distinguish benign from preneoplastic lesions. Destained smears (six defined as normal, six as inflammatory with squamous metaplasia, six as CIN I, six as CIN II, and five as CIN III) were submitted to the Ag-NOR method after staining with Orange G and EA36. Ag-NOR count was performed in previously outlined fields on the smears. Statistically significant differences (P < .05) were found between the normal smears, inflammatory smears with squamous metaplasia, and each grade of CIN. We conclude that the Ag-NOR technique could be useful to evaluate cervical smears of doubtful interpretation, using previous demarcation of the abnormal fields/cells.

Female↗

PubMed1997

Mitochondrial myopathy in Senna occidentalis-seed-fed chicken.

Plants of the genus Senna (formerly Cassia) have been recognized as the cause of a natural and experimental syndrome of muscle degeneration frequently leading to death in animals. Histologically, it demonstrated skeletal and cardiac muscle necrosis, with floccular degeneration and proliferation of sarcolemmal nuclei. Recently, it was described as an experimental model of mitochondrial myopathy in hens chronically treated with Senna occidentalis. Currently, skeletal muscles of chicks intoxicated with seeds of the poisonous plant S. occidentalis were studied by histochemistry and electron microscopy. Since birth, the birds were fed ground dried seeds of this plant with a regular chicken ration at a dose of 4% for 11 days. Microscopic examination revealed, besides muscle-fiber atrophy, lipid storage in most fibers and a moderate amount of cytochrome oxidase-negative fibers. By electron microscopy, enlarged mitochondria with disrupted or excessively branched cristae were seen. This picture was characteristic of mitochondrial myopathy. These findings have hitherto remained unnoticed in skeletal muscle of young birds treated with S. occidentalis.

Animal Feed↗

PubMed1997

Study of organizer nucleolar regions by the argyrophil technique in cervical intraepithelial neoplasias.

Thirty three biopsies of the uterine cervix were studied by the AgNOR method, that identifies the nucleolar organizer regions. These comprised 9 cases of cervicitis (with or without squamous metaplasia), 9 cases of cervical intraepithelial neoplasia grade I (CIN I), 8 CIN II and 10 CIN III. A hundred cells were counted and classified according to the number of AgNOR dots. We use a more practical and fast method of AgNOR dots counting in cervical intraepithelial neoplasia, in that we exclude the two basal layers and count only cells with 4 or more dots. Statistically significant differences for AgNOR dots were found between cervicitis or CIN I and CIN II cases (p < 0.02) and between CIN II and CIN III cases (p < 0.001). No statistical difference was found between the cases of cervicitis and CIN I. It was concluded that this method of AgNOR counting can be useful in the identification and classification of individual cases intraepithelial neoplasia and their differentiation from eventual difficult cases of cervicitis.

Biopsy↗

PubMed1997

Esophageal ulcers in AIDS.

Thirty five esophageal biopsies from AIDS patients with clinical symptoms of esophagitis sent to "Emilio Ribas Institute", Pathology Laboratory, in a 2 year period were revised for possible infectious agents. Microorganisms were seen in 17 cases (48.6%). In 6 cases (17.1%), Acid-Fast bacilli were observed. One of these cases also had characteristic cytomegalic inclusions in endothelial cells. Inflammatory responses were composed of lymphocytes, some plasma cells and many histiocytes, with absence of giant cells in 4 cases of mycobacteriosis; in the other 2 cases, acid-fast bacilli were seen over the epithelium. Exclusive infection by cytomegalovirus was detected in 5 cases (14.3%), and candidiasis in 5 cases (14.3%). In one case there was association of cytomegalovirus and candidiasis. Esophageal ulcers in AIDS patients caused by Mycobacterium sp, may be more common than previously reported, and certainly an overlooked diagnosis. Once esophageal biopsy is an easy diagnostic procedure, this method may be used in routine screening for tuberculosis in patients with AIDS.

AIDS-Related Opportunistic Infections↗

PubMed1997

Cerebral amebiasis in the acquired immunodeficiency syndrome.

Rare cases of cerebral amebiasis have been described in AIDS patients. We report the case of a 46 year-old homosexual man with AIDS who developed an intermittent amnesia and a right palpebral ptosis. The cerebrospinal fluid contained 169 cells (75% lymphocytes). The patient died five days after hospitalization. Necropsy revealed thrombosis of small vessels of the periventricular regions as well as necrosis and hemorrhage of the periventricular tissue, cerebellum and brainstem. The inflammatory process was scarce and composed mainly of CD-68 positive macrophages. In these regions as well as in meninges there were many trophozoites of ameba of the Acanthamoeba group. Although cerebral amebiasis is rare even in AIDS, the clinician should be attentive to this diagnosis in patients with an insidious encephalitis and cerebral cognitive abnormalities, with or without focal motor signs.

AIDS-Related Opportunistic Infections↗

PubMed1996

[Organophosphate-induced myotoxicity].

Organophosphates comprise a group of chemical compounds extensively used in farming as insecticides, which cause accidental poisoning in animals and men and are also used in suicide attempts. The toxicity of these compounds is due especially to the cardiac and respiratory impairment in consequence of autonomic nervous system disorders. However, it is known that some of these products induce a myopathy in experimental animals and humans. This myopathy is characterized by muscle cell degeneration, involving above all the respiratory muscles. Based on the fact that this involvement certainly enhances the respiratory impairment, this study offers an experimental method for routine evaluation of organophosphate myotoxicity, using a minimal and sufficient battery of stains and histochemical reactions, for muscle necrosis quantification. For this purpose, albino rats (Wistar) treated with the organophosphate paraoxon, were used both with and without antidotes (atropine or pralidoxime). Muscle fiber necrosis in the diaphragm of the rats treated with paraoxon or paraoxon and atropine, that affected about 15% of the fibers in some areas, was detected. In the group treated with paraoxon and pralidoxime, a minimal necrosis was seen, revealing a protective role of this later antidote during the development of myopathy.

Animals↗

PubMed1995

Skeletal muscle pathology in systemic sclerosis.

OBJECTIVE: Systemic sclerosis (SSc) is characterized by abnormal deposition of collagen in the skin and by visceral involvement. Muscle weakness is a relatively frequent complication of SSc, although severity varies. We studied muscle pathology in patients with SSc with progressive muscle involvement. METHODS: We performed histochemical and immunohistochemical investigations to detect neural cell adhesion molecule (NCAM). RESULTS: Five of the 6 cases of SSc expressed NCAM in atrophic angulated fibers (some fibers stained heavily with oxidative enzymes). CONCLUSION: Neurogenic involvement in SSc is more frequent than reported.

Adolescent↗

PubMed1995

Empyema with malakoplakic-like lesions by Rhodococcus equi as a presentation of HIV infection.

Rhodococcus equi (Corynebacterium equi) is an aerobic actinomycetes, well described as a cause of pulmonary infection in different animals as horses, pigs and cows. This pathogen has a coccobacillar aspect and a variable acid-fast stain in tissues. Rare cases of human infection by Rhodococcus species were described, the majority by Rhodococcus equi, especially in patients with immunodeficiency syndrome (AIDS) in advanced stages of the disease. Usually the diagnosis of infections by Rhodococcus species is performed by positive blood or bronchoalveolar lavage cultures. Here we described a case of a pleuro-pulmonary infection by Rhodococcus equi, with malakoplakic-like lesions, that was the first manifestation of AIDS, whose diagnosis was performed by pleural biopsy (acid-fast bacteria with a variable coccobacillar aspect inside macrophages) and pleural fluid culture.

AIDS-Related Opportunistic Infections↗

PubMed1994

An unusual case of muscular limb-girdle dystrophy and mitochondrial myopathy.

Limb-girdle muscular weakness and wasting could be caused by different diseases (inflammatory and hereditary myopathies, muscular dystrophies and neurogenic atrophies). Among these, Limb-Girdle Muscular Dystrophy (LGMD) is an heterogeneous group of pathologies that have progressive proximal limbs and girdle weakness, with some dystrophic features by the muscle biopsy. We studied a case of LGMD in an adult man with a typical histological and histochemical profile, associated to a mitochondrial deficit characterized by presence of ragged-red fibers, a histochemical Cytochrome Oxidase deficiency and abnormal mitochondria by ultrastructure.

Adult↗