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Biomedical subjects

I Hod

Publications and source records attributed to I Hod.

At least 19 recordsLinked to original sources

Collagen subtype pattern in normal and varicose saphenous veins in humans.

Our present study was to determine the collagen subtype pattern in the greater saphenous vein of the lower limb, obtained from 21 normal (macroscopically and ultrastructurally non-varicose vein segments from non-varicose subjects) and 37 varicose subjects, and to compare affected (macroscopically and ultrastructurally varicose segments from varicose veins) vs. non-affected (macroscopically and ultrastructurally non-varicose segments from varicose veins) segments (16). After elastase pretreatment and partial pepsin digestion, types I, III & V collagens (CI, CIII, CV) were extracted selectively by differential salt precipitation and measured quantitatively in samples obtained from normal and varicose saphenous veins-either affected or unaffected segments. Significant elevations of water (p < 0.05) and collagen type I [CI] (p < 0.01) content in varicose veins (both affected and unaffected segments) as compared with normal saphenous veins were observed. The collagen type III (CIII) and collagen type V (CV) content of varicose veins were found to be slightly reduced as compared to normal veins and consequently the CI/(CIII+CV) ratio in varicose veins increased significantly (p < 0.02) as compared to normal veins. Elevation of the CI/(CIII+CV) ratio in varicose veins may cause considerable weakening of the venous wall, further supporting the "weak wall" theory of varicose vein etiology.

Case-Control Studies↗

Therapeutic effects of estradiol benzoate on development of collagen-induced arthritis (CIA) in the Lewis rat are mediated via suppression of the humoral response against denatured collagen type II (CII).

The effects of estradiol benzoate (EB) on the development of anti-CII antibodies and their pathogenic potential were studied during the progress of established CIA in the rat. CIA was induced in mature female Lewis rats by two subcutaneous inoculations containing bovine native CII (BCIIn), emulsified in Freund's incomplete adjuvant. Clinical arthritis fully developed by day 18 and then EB (1 mg/kg body wt per day, diluted in corn oil (CO)) was administered intramuscularly every second day thereafter. Antibodies binding four different CIIs (bovine or rat, either native or heat-denatured) were detected in sera and joint tissue extracts by means of solid-phase ELISA. Pharmacological doses of EB (>0.2 mg/kg body wt per day) caused significant remission of established CIA 5-7 days after treatment, and selectively suppressed the production of antibodies specific for denatured CII. To evaluate the arthritogenic potential of circulating anti-CIId IgG, transfer experiments were performed. IgG anti-CIIn, purified from EB-treated CIA rats, was not arthritogenic, whereas IgG anti-denatured (CIId), purified from CO-treated CIA rats, caused severe passive arthritis. Furthermore, pretreatment with rat CIId protected against subsequent induction of CIA, and this protection was associated with suppressed antibody production against CIId. Collectively, our results indicate that antibodies specific for CIId are involved in the pathogenesis of CIA, and that oestrogen-related remission of clinical arthritis may by caused by a selective suppression of antibodies produced against degraded/denatured CII.

Animals↗

Quantitative histomorphology of the blind mole rat harderian gland.

Anatomical, histological and morphometric studies have been performed on the harderian gland and its surroundings in the blind mole rat (Spalax ehrenbergi). The gland is tubuloalveolar with no true duct system. All ducts within the gland are formed by a single epithelial cell type and drain into a wide secretory duct. This opens into the conjunctival sac which serves as a reservoir for harderian secretions. Drainage from the conjunctival sac follows 2 possible routes: one through the nasolacrimal duct to the external nasal cavity, the other through a unique excretory duct that emerges from the anteromedial part of the conjunctival sac and runs through the dermis to the skin, opening at the base of a hair follicle. The function of this newly described duct is discussed. Morphometric studies revealed that the lumen volume fraction in the female, slightly smaller than that of the male during the summer, becomes significantly greater during the winter breeding season. The dimorphism and seasonal variations found in the gland acini suggests that the gland may be implicated in pheromone production.

Animals↗

The enigma of parkinsonism in chronic borderline mercury intoxication, resolved by challenge with penicillamine.

A 47 year old female dentist suffered from hemiparkinsonism which had started eighteen months earlier and was manifested mainly by resting tremor and cogwheel rigidity. A baseline quantitative urinary mercury excretion was 46 micrograms/day. The patient was treated with chelating agent d-penicillamine for a week. Chelation therapy resulted in clinical improvement of parkinsonism and in dynamic changes in daily urinary mercury excretion with a prompt increase to 79 micrograms/day, a subsequent decline followed by increase in the mercury urinary excretion. After a week chelation therapy was stopped. During a follow-up period of five years, the neurological status remained unchanged after the initial penicillamine-induced improvement. This case may be evidence, therefore, of a rare clinical variant of elemental mercury intoxication associated with parkinsonism, in the absence of most classical neuropsychiatric signs of chronic mercurialism.

Chelating Agents↗

L'homme qui rit: inappropriate laughter and release phenomena of the frontal subdominant lobe.

Witzelsucht and moria are time-honored neurobehavioral terms. Witzelsucht is a tendency to tell inappropriate jokes, and moria is euphoric behavior. Focal right-orbitofrontal parenchymal lesion is often the anatomical substrate for these behavioral attitudes. This case report presents a patient with a longstanding witzelsucht-moria behavior. Single photon emission computerized tomography (SPECT) showed hypoperfused right-frontoparietal area in the absence of structural damage.

Adult↗

Impulsive artistic creativity as a presentation of transient cognitive alterations.

A 27-year-old right-handed male mosaic artisan who had not shown any interest in drawing or artistic activity was admitted to the Department of Neurology for attacks of bizarre behavior and convulsive disorder. The patient reported feeling "waves" engulfing him during the attacks, leaving him floating helplessly. During some attacks, the patient impulsively initiated drawing activity. Interictal sleep-deprivation EEG showed a left frontotemporal focus of paroxysmal discharge. Brain tomography with SPECT showed low 99Tc-HMPAO uptake in the left frontoparietal region. Psychodiagnostic tests gave evidence of dysfunction of the left frontal region, with preference of the right hemisphere. It is suggested that the attacks of altered cognitive state were, in this case, provoked by spreading depression of the left hemisphere, while the integrative functions of the right hemisphere remained intact. Thus, the impulsive artistic creativity during the attacks may represent a "release phenomenon" of the complex visuospatial skills of the right (subdominant) hemisphere. This symptomatology of transient cognitive alterations is unique and, to the best of our knowledge, has not been previously reported.

Adult↗

The scanning electron microscope in the pathology of varicose veins.

We studied varices of the lower limb by scanning electron microscope (SEM) in 29 women who had undergone surgery under local anesthesia for symptomatic varicose veins. Their ages ranged between 19 and 42 years (average 30). They were all diagnosed as having incompetence of the valve at the saphenofemoral junction. The surgical procedure was high ligation of the long saphenous vein, excision of the upper portion of the vein and multiple excision of all the varices along the leg through several tiny incisions. Segments of the removed varices and the upper portion of the long saphenous vein were prepared and studied by the Jeol scanning electron microscope (Japan, model 355c). We found no changes in the intima or adventitia and no changes in any of the upper valves of the saphenous vein; however, varying degrees of thinning of the media of the venous wall were seen, which coincided with the areas of varicose dilatation between areas that retained their normal configuration. Our study therefore supports the "weak vein wall" theory concerning the etiology of varicose veins, and confirms that surgery for varicose veins of the lower limb must concentrate on removal of the varices themselves. Since these often lie outside the long saphenous vein, routine stripping is neither advisable nor effective.

Adult↗

Cell membrane activities and regeneration mechanisms as therapy mediators in moxibustion and acupuncture treatments: theoretical considerations.

Needling by acupuncture or heating by moxibustion, the major Chinese medicine modalities, include tissue destruction or increased permeability of cell membrane. Both action potential activities and the release of cellular metabolites responsible for regeneration occurs. These phenomena are eventually abolished by local and systemic inhibitory elements being metabolites or neurogenic. The inhibitory effect induced by the acupuncture and moxibustion and directed to the manipulation site of these modalities may affect other anatomical sites and reduce or prevent neoplastic growth and neuromuscular or cardiac membrane activity disturbances.

Acupuncture Therapy↗

Serratia marcescens infected silk suture rejected by combined acupuncture, moxibustion and low-power laser therapy from the abdominal fascia.

Upper abdominal pains lasting 12 years after cholecystectomy, were improved in an 82-year-old woman following the rejection of indigestable silk surgical sutures induced by combined therapy of acupuncture, moxibustion and low-power laser beam irradiation directed to an old post-cholecystectomy scar. An inflammatory reaction followed by granulation tissue mass was developed. Embedded in the granulation tissue were the above mentioned silk sutures which finally were expelled through the skin at the operation scar. A surgical procedure suggested to the patient, in case of acupuncture therapy failure, was obviously avoided. Serratia-marcescens infection of the expelled material was bacteriologically defined.

Abdomen↗

Immobilization stress and direct glucocorticoid effects on rat septohippocampus.

The rat septohippocampal cholinergic system to a large extent regulates the adaptive physiological and behavioral response to stress. The mesoseptal dopaminergic (DA) system, one of the converging inputs to the lateral septum, exerts a tonic inhibitory action on the septohippocampal cholinergic neurons. High concentrations of pituitary-adrenocortical hormones in plasma may activate the septohippocampal cholinergic system. We have sought to determine whether this mode of activation may be directly initiated by hormonal action on the cholinergic terminals, or indirectly induced through an alteration in the DA septal inputs. The results indicate that stress initiates rapid and transient changes in DA uptake by septal DA terminals, changes which probably contribute to the initial transient activation of the hippocampal cholinergic system. While the effects of glucocorticoids, observed in vitro, may mimic the enhanced ACh release in stress, they do not mimic the increased choline uptake. Nevertheless, high glucocorticoid concentrations may act directly on septal dopaminergic terminals to reduce their DA uptake capacity. These results imply that the septohippocampal cholinergic activity represents an integrative pathway for neuronal and hormonal signals of stress.

Animals↗

Sheep bronchoalveolar carcinoma: tissue associated protein complex (TAPC) in normal lung tissue and in the tumor differed quantitatively.

Sheep lungs experimentally and naturally affected by bronchoalveolar carcinoma were washed out exhaustively of soluble components by phosphate-buffered saline, pH 7.4 (PBS), followed by glycine buffer, pH 2.8 (GB), and then again by 1M KCl followed by PBS. The tissue matrix (TM) of the tumor-free region and the tumor-affected tissue were analysed separately by sodium dodecyl sulfate (SDS) polyacrylamide electrophoresis. Normal lung tissues obtained from normal sheep served as controls. Several protein fractions and fragments, identified in both the normal and the tumorous lung, have the molecular weight (MW) of 130,000-228,000, as compared with the major soluble tissue associated protein having MW of 70,000. Coomassie blue staining used in the SDS polyacrylamide system and alkaline phosphatase immunoreaction used in the Enzyme Linked Immunosorbant Assay (ELISA) showed tenfold increased concentration of the TAPC in the TM of the tumor tissue and in the blood of tumor-affected animals, respectively. Total concentration of the TAPC in the serum of tumor-affected animals was higher than in the normal. Immunofluorescent antibody test (IAT) detected the TAPC in the cytoplasm of tumor as well as in normal lung cells, and the study suggested that the TAPC reaches the peripheral blood during tissue destruction occurring at the tumor site, as observed by light and electron microscopy (LM and EM). The concentration of each of the TAPC fractions was higher in the tumor-affected sheep lung as compared with normal sheep lung. Antibodies prepared against the TAPC fractions were toxic to sheep lung cells in tissue culture. Tumor cells were more susceptible.

Adenocarcinoma, Bronchiolo-Alveolar↗

In vitro presynaptic modulation of cholinergic hippocampal activity by pituitary-adrenocortical hormones.

In vivo studies have shown that high blood concentrations of pituitary-adrenocortical hormones can activate the hippocampal cholinergic terminals. Incubation of hippocampal synaptosomal preparations with methylprednisolone, or with ACTH at concentrations comparable to stress-induced high concentrations in plasma, did not have any significant effects on the cholinergic parameters measured under unactivated conditions. In the presence of either high K+ or of ACh, choline uptake was decreased. This decrease was not affected by methylprednisolone. However, methylprednisolone did enhance ACh release both after a previous increase (induced by K+) or a decrease (induced by ACh) of ACh release. In contrast, ACTH had no direct effects on either unactivated or K+-stimulated synaptosomes. Thus, a differential effect was exerted by methylprednisolone on the two presynaptic regulatory mechanisms: choline uptake (no change) and ACh release (increase). We suggest that the activation, observed in vivo, resulted mainly from indirect action of the hormones on the hippocampal cholinergic terminals, in view of the fact that the direct effect in vitro was partial.

Acetylcholine↗