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PubMed2001

Artificial neural networks for discriminating pathologic from normal peripheral vascular tissue.

The identification of the state of human peripheral vascular tissue by using artificial neural networks is discussed in this paper. Two different laser emission lines (He-Cd, Ar+) are used to excite the chromophores of tissue samples. The fluorescence spectrum obtained, is passed through a nonlinear filter based on a high-order (HO) neural network neural network (NN) [HONN] whose weights are updated by stable learning laws, to perform feature extraction. The values of the feature vector reveal information regarding the tissue state. Then a classical multilayer perceptron is employed to serve as a classifier of the feature vector, giving 100% successful results for the specific data set considered. Our method achieves not only the discrimination between normal and pathologic human tissue, but also the successful discrimination between the different types of pathologic tissue (fibrous, calcified). Furthermore, the small time needed to acquire and analyze the fluorescence spectra together with the high rates of success, proves our method very attractive for real-time applications.

Arteriosclerosis↗
PubMed1978

Guillain-Barré syndrome: demonstration of antibodies to peripheral nerve tissue.

Sera from 30 patients with acute Guillain-Barré syndrome were tested for the presence of antibodies to peripheral nerve tissue using the antiglobulin consumption test. An increased binding of IgG was observed in 15 out of 30 sera and in these sera F(ab')2 fragments prepared from IgG retained the capacity to combine with peripheral nerve tissue, suggesting an antigen-antibody interaction. The specificity for peripheral nerve tissue was demonstrated by absorption experiments. F(ab')2 fragments prepared from IgG of normal sera, however, failed to react with the tissue, suggesting a non-specific binding through the Fc part of the molecule. In sera from patients fully recovered from the Guillain-Barré syndrome and from patients with other neuropathies, no increased binding of IgG was observed.

Acute Disease↗
PubMed1985

Human B cell development. I. Phenotypic differences of B lymphocytes in the bone marrow and peripheral lymphoid tissue.

The phenotype of B lineage cells (TdT+, pre-B, IgM+, IgD-, and IgM+,IgD+) in infant and adult human bone marrow was compared with that of B cells seen in peripheral tissues such as tonsil and blood. The range of B cell-associated antibodies used included four reagents with greater than 90% reactivity on peripheral B cells: RFB4 and To15 (both p135, corresponding to CD22), RFB6 (p140 corresponding to CD21), and Y29/55, a unique B cell-specific antibody. In addition, AL-1, an antibody with virtually no reactivity against peripheral B cells was also used. The BM cell subpopulations were heterogeneous in respect of antibody reactivity. The TdT+, pre-B and IgM+, IgD- cells were AL-1+ but did not express membrane antigens recognized by the antibodies To15, RFB4 (CD22), and RFB6 (CD21). TdT+, pre-B cells, and 50% of IgM+, IgD- BM B cells were also unreactive with antibody Y29/55, the other 50% being Y29/55+. In contrast, the IgM+,IgD+ BM B cells, like peripheral B cells, were positive with antibodies To15, RFB4, RFB6, and Y29/55, but reacted only in small numbers with AL-1. The orderly differentiation-linked display of these antigens was also suggested by the findings that normal TdT+, pre-B, and IgM+,IgD- cells expressed the To15 and RFB4 (CD22) antigens in their cytoplasm (in the Golgi region). This observation was confirmed in malignant common acute lymphoblastic and pre-B blast cells, as well as in the corresponding permanent cell lines KM3 and NALM-6. In these lines the membrane expression of To15 and RFB4 could be induced by phorbol ester during a 48 to 72 hr culture period.

Adolescent↗
PubMed1982

In vivo effect of methylmercury on protein synthesis in peripheral nervous tissues of the rat.

The in vivo rates of protein synthesis in the peripheral nervous tissues of methylmercury-treated rats (10 mg/kg/day, for 7 days) have been estimated with improved methods by the injection of a large amount of [1-14C]valine of low specific activity. Protein synthesis activity in the dorsal root ganglia was inhibited to the extent of 60% of the control as early as day 5 and this continued to the symptomatic period (day 15) on which crossing of hind limbs, a typical sign of organomercurial poisoning, was observed in the animals. The sciatic nerves and dorsal roots increased protein synthesis by 56% at the symptomatic period. These increases in protein synthesis may be due to the stimulation of reactivity of Schwann's cells. On the contrary, the protein synthesis in the ventral roots showed a gradual decrease as the intoxication proceeded and decreased to 73% of the control at the symptomatic period, being similar to the case of brain. The double-labeling studies with sodium dodecyl sulfate/polyacrylamide gel electrophoresis exhibited that methylmercury inhibited the synthesis of the dorsal root ganglion proteins non-uniformly in various apparent molecular sizes, especially on day 10.

Animals↗
PubMed1998

Pathophysiology of the kallikrein-kinin system in mammalian nervous tissue.

The nervous system and peripheral tissues in mammals contain a large number of biologically active peptides and proteases that function as neurotransmitters or neuromodulators in the nervous system, as hormones or cellular mediators in peripheral tissue, and play a role in human neurological diseases. The existence and possible functional relevance of bradykinin and kallidin (the peptides), kallikreins (the proteolytic enzymes), and kininases (the peptidases) in neurophysiology and neuropathological states are discussed in this review. Tissue kallikrein, the major cellular kinin-generating enzyme, has been localised in various areas of the mammalian brain. Functionally, it may assist also in the normal turnover of brain proteins and the processing of peptide-hormones, neurotransmitters, and some of the nerve growth factors that are essential for normal neuronal function and synaptic transmission. A specific class of kininases, peptidases responsible for the rapid degradation of kinins, is considered to be identical to enkephalinase A. Additionally, kinins are known to mediate inflammation, a cardinal feature of which is pain, and the clearest evidence for a primary neuronal role exists so far in the activation by kinins of peripherally located nociceptive receptors on C-fibre terminals that transmit and modulate pain perception. Kinins are also important in vascular homeostasis, the release of excitatory amino acid neurotransmitters, and the modulation of cerebral cellular immunity. The two kinin receptors, B2 and B1, that modulate the cellular actions of kinins have been demonstrated in animal neural tissue, neural cells in culture, and various areas of the human brain. Their localisation in glial tissue and neural centres, important in the regulation of cardiovascular homeostasis and nociception, suggests that the kinin system may play a functional role in the nervous system.

Alzheimer Disease↗
PubMed1987

Decrease in protein phosphorylation in central and peripheral nervous tissues of methylmercury-treated rat.

The protein phosphorylation in extracts of nervous tissues of rats acutely exposed to methylmercury chloride (seven daily injections of 10 mg methylmercury chloride/kg body weight) was examined. In the brain, the phosphorylating activity was dependent on cAMP and Mg2+. The effect of methylmercury on the phosphorylation of brain proteins, including tubulin and MAP-2, was hardly discernible. In peripheral nervous tissues such as the dorsal and ventral roots, sciatic nerves and dorsal root ganglia, the phosphorylating activity was dependent on Ca2+, and the maximal activity was obtained when the tissues were extracted in the presence of 1% Triton X-100. SDS-Polyacrylamide gel electrophoresis revealed that the major phosphorylated proteins in the peripheral tissues were myelin proteins. The effects of methylmercury were not uniform regarding protein species and tissues. The most marked changes were observed in sciatic nerves, in which phosphorylation of the 33 kDa, 28 kDa, 19 kDa, 18 kDa and 15 kDa proteins was significantly decreased in the symptomatic phase of intoxication.

Animals↗
PubMed1994

Functional studies on MEL-14+ and MEL-14- T cells in peripheral lymphoid tissues.

Functions of MEL-14+ T cells and MEL-14- T cells in peripheral lymphoid tissues were analyzed and compared. The MEL-14- T cells, representing a minor subpopulation of spleen and lymph node T cells, generated considerably higher mixed lymphocyte reaction and mitogen responses than the MEL-14+ T cells in any lymphoid tissues studied. Furthermore, upon stimulation with ConA the MEL-14- CD8+ T cells produced significantly larger amounts of IL-2 and IFN-gamma than MEL-14+ CD8+ T cells did. A similar but less marked observation was obtained with the CD4+ T cell population. Furthermore, when B10.BR mice were immunized with AKR (Mls-1a) spleen cells, the proportion of the Mls-1a reactive V beta 6+ T cells from draining lymph nodes increased and a substantial proportion of the increasing V beta 6+ T cells was shown to be MEL-14-. The present findings on the whole indicate that MEL-14- T cells in the peripheral lymphoid tissues are at functionally high levels and may represent memory cells which have been previously stimulated in vivo.

Animals↗
PubMed1991

Substance P and the inflammatory and immune response.

These findings suggest that SP may have proinflammatory actions in both the peripheral tissue and the central nervous system after tissue injury. Although the possibility that the same neuropeptide could have actions in both the brain and the peripheral tissues is certainly not without precedent, there is a key difference in the source of the ligand in these tissues. Unlike peripheral tissues such as the gastrointestinal tract or skin, where there is a dense innervation by SP-containing dorsal root ganglion neurons, the brain lacks such a sensory innervation. This important difference raises the question as to the possible origin of the SP that could occupy the SP receptors expressed by the CNS glia after neuronal injury. Whereas the answer to this question is currently unknown, an important clue may be the findings that circulating leukocytes have been reported to synthesize neuropeptides such as ACTH, opiates, and SP. To begin to fully understand the role that SP may play in coordinating the inflammatory and immune response to tissue injury, we must first understand where SP fits into the cascade of events that occur after tissue injury, what events lead to nociceptor sensitization (which may lead to an increase in SP release), and what regulates SP receptor expression (which may be involved in the direction of leukocytes to the site of injury, plasma extravasation, or the proliferation/hypertrophy of reactive astrocytes). Although this may seem like a daunting task, several recent advances including the cloning of the three mammalian tachykinin receptors and the introduction of highly potent and specific SP receptor antagonists should make this a highly fruitful field of investigation.

Animals↗
PubMed1999

Tissue heat content and distribution during and after cardiopulmonary bypass at 17 degrees C.

UNLABELLED: We measured afterdrop and peripheral tissue temperature distribution in eight patients cooled to approximately 17 degrees C during cardiopulmonary bypass and subsequently rewarmed to 36.5 degrees C. A nasopharyngeal probe evaluated trunk and head temperature and heat content. Peripheral tissue temperature (arm and leg temperature) and heat content were estimated using fourth-order regressions and integration over volume from 30 tissue and skin temperatures. Peripheral tissue temperature decreased to 19.7+/-0.9 degrees C during bypass and subsequently increased to 34.3+/-0.7 degrees C during 104+/-18 min of rewarming. The core-to-peripheral tissue temperature gradient was -5.9+/-0.9 degrees C at the end of cooling and 4.7+/-1.5 degrees C at the end of rewarming. The core-temperature afterdrop was 2.2+/-0.4 degrees C and lasted 89+/-15 min. It was associated with 1.1+/-0.7 degrees C peripheral warming. At the end of cooling, temperatures at the center of the upper and lower thigh were (respectively) 8.0+/-5.2 degrees C and 7.3+/-4.2 degrees C cooler than skin temperature. On completion of rewarming, tissue at the center of the upper and lower thigh were (respectively) 7.0+/-2.2 degrees C and 6.4+/-2.3 degrees C warmer than the skin. When estimated systemic heat loss was included in the calculation, redistribution accounted for 73% of the afterdrop, which is similar to the contribution observed previously in nonsurgical volunteers. IMPLICATIONS: Temperature afterdrop after bypass at 17 degrees C was 2.2+/-0.4 degrees C, with approximately 73% of the decrease in core temperature resulting from core-to-peripheral redistribution of body heat. Cooling and rewarming were associated with large radial tissue temperature gradients in the thigh.

Adult↗
PubMed1997

Aromatase in human bone tissue.

Peripheral aromatization of androgens exert estrogenic actions in many tissues. Recently in situ production of estrogens by aromatase was detected in human bone and cultured osteoblasts and has been proposed to participate in the maintenance of bone mass. We examined aromatase expression by immunohistochemistry and mRNA in situ hybridization in 16 cases of tibia (female 2 male, 14 female, 62 +/- 5.2 years old) and quantified the level of aromatase mRNA in 28 cases of rib, femur, and lumbar vertebrae (16 male, 12 female, 58.0 +/- 11.3 years old) by reverse transcriptase-polymerase chain reaction (RT-PCR) in order to study whether or not and in which cell types aromatase was expressed in human bone tissues. We also studied alternative use of multiple exons 1 of its gene and immunolocalization of type I 17 beta-hydroxysteroid dehydrogenase (HSD), which converts estrone produced by aromatase to estradiol. Strong aromatase immunoreactivity and mRNA hybridization as well as type I 17 beta-HSD immunoreactivity were detected in lining cells, osteoblasts, chondrocytes of articular cartilage, and adipocytes adjacent to bone trabeculae in all the cases examined. Amounts of aromatase mRNA varied greatly among the subjects (11.25 +/- 9.77, 0.61-42.84 attomol/ng of total RNA). The amount of aromatase expression was not correlated with age or gender of the subjects but positively correlated with the degree of osteroporotic changes evaluated by radiological findings of lumbar vertebrae. Analysis of multiple exons 1 revealed that 1b or fibroblast type was predominantly (23/26) utilized as a promoter of aromatase gene expression. These results demonstrated that aromatase is expressed widely in human bone tissue and may play important roles in maintenance of human bone tissue.

17-Hydroxysteroid Dehydrogenases↗
PubMed2004

Primary capillary hemangioblastoma of peripheral soft tissues.

A case of capillary hemangioblastoma located in the peripheral soft tissue of the inner ankle in a 74-year-old woman is presented. The tumor was an unencapsulated but sharply circumscribed nodule 2.5 cm in size, of a yellow-white color. It showed reddish-brown spots with small cysts up to 2 mm filled with blood. Grossly the tumor was not attached to any peripheral nerve. Signs of von Hippel-Lindau's disease were excluded by thorough clinical evaluation. No additional tumor or erythrocytosis was found in the patient clinically. Immunohistochemically, the tumor stromal cell reacted strongly with antibodies to S-100 protein, NSE, and calponin and they were negative with antibodies to GFAP, CD34, CD31, cytokeratins, actin, desmin, EMA, and HMB-45. Endothelium of the capillaries reacted positively with antibodies to CD31, CD34, and Factor VIII-related protein. Capillary pericytes were actin-positive. All cells of the tumor stained positively with antibody to vimentin. MIB1 antibody reacted only in very few cells (<1%). Ultrastructurally, the stromal cells contained electron-lucent cytoplasm with lipid droplets, a small amount of rough endoplasmic reticulum, and glycogen particles. No electron-dense structures typical of secretory granules were seen in the stromal cells. No mutation of coding sequence of VHL gene was found.

Aged↗
PubMed1993

Absence of nonshivering thermogenesis in anesthetized adult humans.

BACKGROUND: Typically, core temperature rapidly decreases after induction of anesthesia, but reaches a stable plateau after several hours. This plateau typically occurs in conjunction with the onset of thermoregulatory vasoconstriction. Decreased heat loss, caused by vasoconstriction, may not be sufficient to establish thermal steady state without a concomitant increase in heat production. Accordingly, the authors tested the hypothesis that nonshivering thermogenesis contributes to thermal steady state during anesthesia. Rewarming from hypothermia is often associated with an afterdrop (a further reduction in core temperature, despite cutaneous warming). Because total body heat content increases during cutaneous warming, heat storage during afterdrop must reflect increased temperature and heat content of the peripheral tissue mass. Thermal balance was measured during rewarming to estimate the thermal capacity of the peripheral tissues. METHODS: Five volunteers were anesthetized with isoflurane and paralyzed with vecuronium. Oxygen consumption was measured during cooling to a core temperature at least 1 degree C less than that which triggered vasoconstriction. Volunteers were subsequently rewarmed using a circulating-water blanket and forced-air warmer. Oxygen consumption and cutaneous heat flux were measured to assess thermal balance and peripheral tissue heat storage during rewarming. RESULTS: The core temperature threshold for vasoconstriction was 35.2 +/- 0.8 degrees C. Oxygen consumption decreased 9 +/- 5%/degrees C during active cooling before vasoconstriction and 9 +/- 3%/degrees C after vasoconstriction. After the start of rewarming, core temperature continued to decrease for an additional 32 +/- 8 min. The magnitude of this afterdrop was 0.6 +/- 0.1 degree C. Peripheral tissue heat storage measured from the start of rewarming until the first net increase in core temperature was 144 +/- 60 kcal, which approximately equals 2 h of resting metabolic heat production. CONCLUSIONS: The authors concluded that nonshivering thermogenesis is not an important thermoregulatory response in adults anesthetized with isoflurane. Afterdrop and delayed core temperature recovery during rewarming reflect the large heat storage capacity of peripheral tissues.

Adult↗
PubMed1999

Alternative exon 3 splicing of the human major protein zero gene in white blood cells and peripheral nerve tissue.

The major protein zero (MPZ) is involved in peripheral myelin folding. Using nested reverse transcription-PCR, we amplified several fragments of MPZ mRNAs in white blood cells and in peripheral nerve tissue. Cloning of PCR products revealed the existence of three alternative splicing patterns: one resulted in the complete loss of exon 3 and two others induced partial skipping of the exon 3 sequence. All three alternative splicing mechanisms produced a frame-shift and created an identical premature stop codon in exon 4. We conclude that the existence of these MPZ RNA transcript variants may be the result of deliberate splicing decisions and may have functional implications in the cell.

Actins↗
PubMed1990

Peripheral, soft tissue odontomas. Two case reports.

Two cases of rare, peripheral, soft tissue odontomas, in different growth phases, are reported. Case one, discovered in an early, rapid growth phase, had no radiographic appearance, was presumed to be a periodontal abscess, and presented a diagnostic challenge. Case two was diagnosed radiographically in its mature phase. Both were treated successfully by excisional biopsy and did not recur. Comparisons are made to the classic intrabony odontomas.

Adult↗
PubMed1998

Characterisation of xenobiotic-metabolising enzyme expression in human bronchial mucosa and peripheral lung tissues.

The human respiratory epithelium is in direct contact with chemical carcinogens and toxins in inhaled air. Therefore, the activities of xenobiotic-metabolising enzymes in this epithelium could modulate respiratory toxicity and carcinogenesis. We determined the expression of several xenobiotic-metabolising enzymes, including phase I and phase II enzymes, in human bronchial mucosa and peripheral lung tissues. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of phase I enzymes showed CYP1A1 and CYP2C (CYP2C8 and CYP2C18) mRNA expression in all of the 14 bronchial mucosa specimens. CYP2A6 and CYP2B6 mRNAs were found in 85% of the samples, whereas 50 and 90% of the tissues displayed CYP2E1 and CYP3A5 expression, respectively. However, CYP1A2, CYP2D6 and CYP3A4 mRNAs were not detected in all samples analysed. Normal human bronchial epithelial cells (NHBE cells) cultured in serum-free conditions showed reduced P450 expression in comparison with the bronchial mucosal samples. Similar to the bronchial mucosa, the peripheral lung tissues expressed CYP1A1, CYP2A6, CYP2B6, CYP2C (CYP2C8 and CYP2C18), CYP2E1 and CYP3A5 mRNAs, but did not show detectable levels of CYP2D6. Additional P450s, such as CYP1A2 and CYP3A4, were detected. The expression of CYP1A1, CYP1A2, CYP2B6, CYP2E1 and CYP3A4/5 in peripheral lung tissues was confirmed at the protein level, whereas CYP2A6 protein was undetectable. The use of specific primers for the detection of the phase II isoenzymes belonging to the glutathione S-transferase mu (GST mu) and N-acetyl transferase (NAT) families showed that GSTM1 was expressed in 40% of the bronchial mucosa and 25% of the peripheral lung tissues, whereas GSTM3 and NAT1 mRNAs were found in all bronchial and lung samples. Finally, NAT2 expression was detected in all peripheral lung tissues, but was not detected in the bronchus. In conclusion, these results describing the diversity of the xenobiotic-metabolising enzymes expressed in the bronchus and lung tissues indicate that the human respiratory system could significantly and specifically contribute to the activation and metabolism of several environmental procarcinogens.

Adolescent↗
PubMed2004

Constitutive spinal cyclooxygenase-2 participates in the initiation of tissue injury-induced hyperalgesia.

Inhibitors of the isozyme cyclooxygenase-2 (COX-2) represent an important advance in pain management, although where and when these inhibitors can exert their antihyperalgesic actions are not completely understood. Here we show that unlike many peripheral tissues in which COX-2 is only expressed in physiologically significant levels after tissue injury, in the normal rat lumbar spinal cord, the majority of neurons and radial glia constitutively express high levels of COX-2 protein. Immediately after peripheral tissue injury and before any measurable upregulation of COX-2 protein in peripheral tissue or spinal cord, inhibition of constitutively expressed spinal COX-2 reduced injury-induced activation of primary afferent neurons, activation of spinal neurons, and the mechanical and thermal hyperalgesia that normally occurs after peripheral tissue injury. The present data demonstrate that constitutively expressed spinal COX-2 plays an important role in the initial hyperalgesia that follows peripheral tissue injury. These results suggest that blocking constitutive spinal COX-2 before tissue injury may reduce the initial peripheral and central sensitization that occurs after tissue injury.

Animals↗
PubMed1985

Immunohistochemical analysis of the distribution of vimentin in human peripheral lymphoid tissues.

The distribution of the intermediate filament protein vimentin in peripheral lymphoid tissues was determined using a monoclonal antibody. Frozen sections of tissue were stained using an avidin-biotin immunoperoxidase method. The antibody stained endothelial cells in spleen, lymph node, and tonsil. Unusual rod-like structures were revealed in the sinusoid-lining cells of the spleen. A variety of reticulum cells was detected, including fibroblastic reticulum cells, histiocytic reticulum cells (tingible body macrophages), and splenic marginal zone macrophages. Very few lymphocytes were immunoreactive. Only weak cytoplasmic immunoreactivity was observed in lymphocytes of the periarteriolar lymphocyte sheath of the spleen. The monoclonal antibody employed appears to be of limited usefulness in detecting normal lymphocytes, but is strongly reactive with endothelial structures and some types of reticulum cells.

Histocytochemistry↗