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At least 433 records · Page 24Linked to original sources
PubMed2005

In transit/local recurrences in melanoma patients after sentinel node biopsy and therapeutic lymph node dissection.

This study has analyzed the incidence of in transit/local recurrences (IT/LR) in melanoma patients after sentinel node (SLN) biopsy; completion lymph node dissection (CLND) that was performed due to positive node; and therapeutic LND (TLND) due to clinically detected node metastases and factors influencing IT/LR. Between May 1995 and May 2004, 1187 consecutive patients underwent SLN biopsy (median Breslow thickness 2.5 mm) and 224 of them had subsequent CLND. During the same time period, 306 patients had TLND (median Breslow 3.9 mm). The excision margin of primaries was > or =1cm. At median follow-up time of 37.5 months, we analyzed the incidence of IT/LR as the first site of relapse and clinicopathological parameters affecting these recurrences. In SLN-negative cases, IT/LR as the site of the first recurrence were rare (46/963; 4.8%) and; in SLN+/-CLND IT/LR were detected in 45/224 cases (20.1%). IT/LR in SLNB group correlated with presence of SLN metastases (P<0.0001), higher Breslow thickness (P<0.001) and lower extremity localization (P=0.03). In TLND group, IT/LR were observed in 52/306 patients (17%), which is similar to all CLND patients (P=0.3), but less common when analyzing only patients who relapsed (TLND: 52/209 (24.9%) vs. CLND: 45/121 (37.2%); P=0.02). Estimated 3-year overall survival (from the date of relapse) in IT/LR only patients was better than in other types of relapses after LND (29% vs. 8%; P<0.0001). IT/LR incidence in the entire group of SLN+/-CLND patients was similar to that observed in TLND patients and it was affected by presence of nodal metastases, Breslow thickness and lower extremity location.

Adolescent↗
PubMed1975

Light and electron microscopic studies of postcapillary venules in developing human fetal lymph nodes.

Developing lymph nodes from 30 human fetuses with crownrump lengths (CRL) of 38 mm (8.7 wk) to 245 mm (26 wk) were studied by light and electron microscopy. Blood vessels that appear to be postcapillary venules (PCV) are present in nodes of 47 mm CRL and older fetuses. These venules first appear in nodes whehn the nodal population of lymphocytes is sparse. In these early nodes PCV are distributed randomly and consist of a low endothelium, underlying basal lamina and incomplete pericyte sheath. Early nodal PCV are distinguised from other nodal blood vessels by the presence of lymphocyte diapedesis and several luminal lymphocytes. In the late stages of nodal development PCV are the more common non-capillary blood vessel and appear in the parenchyma near the periphery of the node. Late nodal PCV are generally characterized by a cuboidal endothelium that is rich in Golgi apparatus, lysosomes and Weibel-Palade bodies. The lumen and wall of late nodal PCV contain lymphocytes. The relationship between the development of the parenchyma of fetal nodes and the appearance and activity of PCV, the passage of lymphocytes through the PCV wall and the fine structure of developing PCV are described. It is suggested that the lymphocytes that first appear in developing nodes, and the majority of the lymphocytes found in late nodes, migrate to the node via the blood vascular system and enter the nodal parenchyma by passing across PCV endothelium.

Abortion, Spontaneous↗
PubMed1985

The narrowing of high endothelial venules of the rat lymph node.

The lymph node contains blood vessels of a special type, termed "high endothelial venules" (HEVs), which are involved in the process of lymphocyte recirculation. In standard tissue sections, many HEVs exhibit a nearly closed or closed lumen containing small lymphocytes but few, if any, erythrocytes. The question arose as to whether the appearance of HEVs in tissue sections is influenced by the routine method of animal sacrifice and/or of tissue processing. Therefore, the present work investigated the effects on HEVs of sacrificing rats as well as of excising and fixing their nodes with various procedures. It was observed that procedures involving animal bleeding or blood loss from nodes increase the percentage of HEVs exhibiting a nearly closed or closed lumen. The results further revealed that the endothelial thickness and other morphological features of HEVs are modified by this artifactual narrowing of HEVs. The possible significance of the phenomenon is discussed.

Animals↗
PubMed1984

[A case of lymph node aspergillosis].

Lymph node aspergillosis in an otherwise healthy patient receiving neither antibiotic corticosteroid or immunodepressive drug treatment is an uncommon event. In addition the case reported revealed no deficiency in humoral or cellular immunity. The possibility that aspergillosis may occur in cases without identifiable immunodeficiency is therefore put forward.

Adolescent↗
PubMed1991

Cytodiagnosis of metastatic melanoma in the lymph nodes.

Lymph-node aspirates performed over ten years numbering 1,555 showed 8.2 percent of metastatic tumors. Of these, only six percent were metastatic melanomas. Clinical diagnosis was made in three cases. Melanin in the cells made the diagnosis easy. But even in the absence of the pigment as in two amelanotic melanomas, the cytologic features were characteristic.

Adolescent↗
PubMed1970

Virological examination of bovine mammary lymph nodes.

Mammary lymph nodes from 42 Hereford cows culled for poor reproductive performance were examined for cytopathogenic virus and hemadsorption. No evidence of viral infection was detected using the methods employed. Serum from all the animals gave positive reactions to the hemagglutination-inhibition test for bovine myxovirus parainfluenza 3. Six of 12 had neutralizing antibody against bovine virus diarrhea virus, but none of the 12 had neutralizing antibodies against infectious bovine rhinotracheitis virus.

Animals↗
PubMed1998

L-selectin and beta7 integrin synergistically mediate lymphocyte migration to mesenteric lymph nodes.

Mesenteric lymph nodes (MLN) drain the gut where nutritive antigens and pathogens are encountered by lymphocytes of the gut-associated lymphoid tissue. We sought to determine how lymphocytes enter the MLN by studying mice double deficient for beta7 integrins and L-selectin. beta7/L-selectin double-deficient lymphocytes did not migrate into MLN. Most importantly, MLN formation was drastically impaired in beta7/L-selectin double-deficient mice. Lymphocyte numbers in MLN from beta7/L-selectin double-deficient mice were tenfold reduced compared to control mice. A high percentage of the few lymphocytes still detected in MLN from beta7/L-selectin double-deficient mice were CD44hi CD18hi, suggesting alternate migration pathways independent of L-selectin and beta7 integrin for these cells. We conclude that the combination of both molecules, L-selectin and beta7 integrin, is indispensable for MLN formation and that these molecules may mediate lymphocyte migration to MLN in a sequential and synergistical manner.

Animals↗
PubMedDate not supplied

[Doppler ultrasonography of superficial lymph nodes].

Normal lymph nodes (l.n.) are elongated and hypoechoic, with central echogenic hilum on B-mode, while color-doppler (CD) shows central hilar vascularization. Chronic inflammatory l.n. are elongated, with echogenic hilum, hilar vascularization on CD and resistance index (RI) 0.60-0.70. Acute lymphadenitis shows intensive hilar flow with RI<0.60; abscess of l.n. is anechoic with through transmission. Tuberculous l.n. are inhomogenously hypoechoic and rounded, with deformed hilar vascularization on CD, occasionally with centripetal flow. They may mimick malignant l.n. on CD due to vessel dislocation by granulomatous masses. L.n. in stage of micrometastasis are of similar structure as reactive l.n., with preserved hilar vascularization; as the metastasis grows, focal cortical expansion and/or destruction of intranodal structure with dislocation and compression of blood vessels may occur; vascular resistance is consecutively increased; in advanced stage of metastatic growth l.n. becomes rounded, hilum is not visible, cortex is heterogenous, occasionally with hyperechoic keratin deposits, unsharp nodal margin is the sign of extranodal neoplastic spread; mainly peripheral vascularization, with fragmentation, deformation and dislocation of intranodal vessels are seen on CD, with increased RI>0.80; necrotic areas are anechoic and avascular on CD. Lymphomatous nodes have preserved internal structure, sharp margins, hypoechoic cortex, frequently with through transmission; large arborized hilum may be displaced; abundant hilar flow is seen on CD, with normal or slightly increased vascular resistance. Although the sensitivity of B-mode and Doppler features of l.n. is mostly limited (false negative rate is significant), high specificity of some of them establishes sonography as a valuable complementary method in differential diagnosis of lymphadenopathy: the presence of hilar vascularization with RI<0.40 accurately indicates acute lymphadenitis, while predominantly peripheral flow pattern and RI>0.80 are typical of metastatic l.n. High enddiastolic velocities (EDV>9 cm/s) are only rarely seen in metastases, while very low EDV<1 cm/s indicates metastatic lymphadenopathy. As sonography is very suitable imaging method for puncture guidance, B-mode and CD analysis of l.n. need to be combined with aspiration cytology whenever possible, as it may considerably improve the accuracy of non-invasive patient diagnostic work-up. Literature on sonography of l.n. was reviewed, and selection of most relevant articles was made.

Humans↗
PubMed1987

Production of interleukin 2 by human lymph nodes.

Perigastric lymph node cells (LNC) from patients with gastric carcinoma or benign lesions were tested for interleukin 2 (IL 2) production upon stimulation with phytohemagglutinin (PHA), in comparison with that of peripheral blood mononuclear cells (PBM) or spleen cells (SPC). IL 2 activity in the supernatants of LNC cultures from patients with either carcinoma or benign lesions was significantly higher than that of PBM cultures from the same person. There was no significant difference in IL 2 activity between PBM cultures or LNC cultures from patients with carcinoma and patients with benign lesions. Supernatants from LNC cultures were also more active than those obtained from SPC cultures. The production of interleukin 1 (IL 1) in LNC was lower than that in PBM. In LNC, the proportion of OKT3+ cells was similar to that found in PBM, with a prevalence of OKT4+ cells over OKT8+ cells. No differences were found between lymphatic cells from patients with carcinoma and from patients having benign lesions.

Humans↗
PubMed1966

Electron microscopic observations on antibody-producing lymph node cells.

Lymph node cells of rabbits injected with sheep erythrocytes, identified as antibody-producing by their ability to produce plaques of hemolysis in erythrocyte-containing agar layers, have been examined by electron microscopy, by the use of a procedure devised for subjecting single cells to such examination. The antibody-producing cells thus examined were found to fall into two classes, according to the current terminology: some were in the category of lymphocytes, and others, in the category of plasma cells. Within each class, cells were found to vary in certain characteristics, especially in the degree of development of such organelles as the nucleolus, Golgi apparatus, and the endoplasmic reticulum. In the case of the endoplasmic reticulum especially, it could be seen that a series of these plaque-producing cells, ranked in order of increasing size and development of the endoplasmic reticulum, would extend over a considerable range from those lymphocytes with the least developed organelles to the mature plasma cells with the greatest development of these structures.

Animals↗
PubMed1999

Immunohistochemical analysis of nm23-H1 gene product in node-positive lung cancer and lymph nodes.

The nm23-H1 gene product has been considered as an anti-metastatic protein and the level of its expression has been reported to correlate inversely with metastatic potential in some cancers. However, the expression of nm23-H1 gene product in the metastatic sites have not been studied in detail. We examined the expression of nm23-H1 gene product in surgically resected 46 pairs of primary lung cancers and metastatic lymph nodes by immunohistochemistry. The positive staining of nm23-H1 gene product in primary cancers and metastatic lymph nodes were observed in 56.5 and 67.4%, respectively. The heterogeneity of nm23-H1 gene product expression between primary cancers and metastatic lymph nodes was observed in 41.3%. No correlations were found between the nm23-H1 gene product expression in lung cancers and the patients survival. No significant association was also observed between nm23-H1 gene product expression in lymph nodes and the patients survival. There was, furthermore, no correlation between the heterogeneity of nm23-H1 gene product expression and the patients survival. In conclusion, the level of nm23-H1 gene product expression does not significantly reveal prognostic value in node-positive lung cancers. Expression of nm23-H1 gene product in metastatic lymph nodes was also unrelated to patients survival.

Adenocarcinoma↗
PubMed2001

Intralaboratory validation of alternative endpoints in the murine local lymph node assay for the identification of contact allergic potential: primary ear skin irritation and ear-draining lymph node hyperplasia induced by topical chemicals.

We validated a two-tiered murine local lymph node assay (LLNA) with a panel of standard contact (photo)allergens and (photo)irritants with the aim of improving the discrimination between contact (photo) allergenic potential and true skin (photo)irritation potential. We determined ear weights to correlate chemical-induced skin irritation with the ear-draining lymph node (LN) activation potential. During tier I LLNAs, a wide range of concentrations were applied on three consecutive days to the dorsum of both ears. Mice were exposed to UVA light immediately after topical application to determine the photoreactive potential of some test chemicals. Mice were killed 24 h after the last application to determine ear and LN weights and LN cell counts. It was possible to classify the tested chemicals into three groups according to their threshold concentrations for LN activation and skin irritation: (1) chemicals with a low LN activation potential and no or very low skin irritation potential; (2) chemicals with a marked LN activation potential higher than a distinct skin irritation potential; and (3) chemicals with LN activation potential equal to or lower than their skin irritation potential. Group 1 consisted only of contact allergens, indicating that LN activation in the absence of skin irritation points to a contact allergenic activity. Since groups 2 and 3 comprised irritants and contact allergens, a tier II LLNA protocol was used to finally differentiate between true irritants and contact allergens. Briefly, mice were pretreated with mildly to moderately irritating concentrations of the chemical to the shaved back and after 12 days were challenged on the ears as described above in order to elicit a contact allergenic response in the ear skin and the ear-draining LN. With this approach, tier II LLNAs have to be conducted only in cases for which skin irritation potential is in the range of LN activation potential and no structure-activity relationship data indicating a contact allergenic hazard are available.

Administration, Topical↗
PubMed1993

Influence of irritants on lymph node cell proliferation and the detection of contact sensitivity to metal salts in the murine local lymph node assay.

Dimethyl sulfoxide (DMSO) and sodium lauryl sulfate (SLS) are known to cause irritation of the skin, and to enhance the penetration of chemicals into the epidermis. In the present study, the lymph node cell (LNC) proliferative response following exposure to irritants, such as SLS and DMSO, was examined in the murine local lymph node assay (LLNA). Exposure to DMSO or SLS aqueous solution induced a small increase in lymph node cell proliferation compared with aqueous solution alone. Exposure to SLS in DMSO caused a significant increase in LNC proliferation. Further, the effect of addition of the irritants in a vehicle on the detection of contact sensitivity to metal allergens was examined. Application of potassium dichromate and nickel sulfate in DMSO or SLS aqueous solution caused increases in LNC proliferation. Exposure to metal allergen with SLS in DMSO also induced a significant LNC proliferative response, but did not induce a significant increase in stimulation index (increase in 3H-thymidine incorporation relative to vehicle-treated control group). This was because of increased 3H-thymidine incorporation following exposure to SLS-DMSO in the control group. These results suggest that irritants enhance the LNC proliferative responses to metal allergens. The use of SLS in aqueous solution is effective for the detection of sensitivity to water-soluble allergens, such as metal allergens, in the LLNA, as well as the use of DMSO as an application vehicle.

Animals↗
PubMedDate not supplied

Pathologic analysis of sentinel lymph nodes.

The sentinel lymph node (SLN) procedure enables selective targeting of the first draining lymph node, where the initial metastases will form. A negative SLN predicts the absence of tumor metastases in the other regional lymph nodes with a high degree of accuracy. This means that in case of a negative SLN, regional lymph node dissection is no longer necessary. Besides saving patients the significant morbidity associated with lymph node dissection, it will also save costs. Crucial for the success of the SLN procedure is the screening of the SLN for metastases by the pathologist. To this end, several techniques are available such as standard histo- and cytopathological techniques, immunohistochemistry, flow cytometry, and molecular biological techniques. In this paper, the value of these methods for detecting SLN metastases is discussed. Some of these techniques have also appeared to be quite useful for intraoperative evaluation of SLNs. The standard protocol for detection of SLN metastases consists of extensive histopathological investigation including stepped sections stained with hematoxylin and eosin (HE) and immunohistochemistry. Intraoperative frozen section analysis and imprint cytology of SLNs have been shown to be reasonably reliable for detecting breast cancer metastases in SLNs. Further studies are necessary to establish the role of multiparameter flow cytometry and sophisticated molecular biological techniques such as reverse transcription polymerase chain reaction (RT-PCR) in detecting SLN metastases.

Biopsy, Needle↗
PubMed2000

Lymph-borne chemokines and other low molecular weight molecules reach high endothelial venules via specialized conduits while a functional barrier limits access to the lymphocyte microenvironments in lymph node cortex.

Lymph-borne, soluble factors (e.g., chemokines and others) influence lymphocyte recirculation and endothelial phenotype at high endothelial venules (HEVs) in lymph node cortex. Yet the route lymph-borne soluble molecules travel from the subcapsular sinus to the HEVs is unclear. Therefore, we injected subcutaneously into mice and rats a wide variety of fluorophore-labeled, soluble molecules and examined their distribution in the draining lymph nodes. Rather than percolating throughout the draining lymph node, all molecules, including microbial lipopolysaccharide, were very visible in the subcapsular and medullary sinuses but were largely excluded from the cortical lymphocyte microenvironments. Exclusion prevailed even during the acute lymph node enlargement accompanying viral infection. However, low molecular mass (MW) molecules, including chemokines, did gain entry into the cortex, but in a very defined manner. Low MW, fluorophore-labeled molecules highlighted the subcapsular sinus, the reticular fibers, and the abluminal and luminal surfaces of the associated HEVs. These low MW molecules were in the fibers of the reticular network, a meshwork of collagen fibers ensheathed by fibroblastic reticular cells that connects the subcapsular sinus floor and the HEVs by intertwining with their basement membranes. Thus, low MW, lymph-borne molecules, including chemokines, traveled rapidly from the subcapsular sinus to the HEVs using the reticular network as a conduit.

Animals↗