General Connective Tissue

Histology blog entry for August 29, 2008 about general connective tissue

Could the super-pulsed CO2 laser be used for oral excisional biopsies?

Background. The main purpose of a biopsy is microscopic examination and diagnosis. Keeping the margins of specimens safe and readable is always fundamental to detecting marginal infiltrations or malignant transformation. Numerous options and tools have been introduced for biopsy procedures. Lasers are one of these options that provide many enhancements to clinical and surgical biopsy procedures in comparison to scalpels. Objectives. The aim of the present study is to quantify the thermal artefacts in histological specimens obtained using a CO2 laser from different oral mucosal lesions and to evaluate if the resulting thermal effect hinders the histological examination. This aim is accomplished through quantitatively and qualitatively assessing the thermal effect in both the epithelium and connective tissue. Material and methods. A super-pulsed CO2 laser (10,600 nm) was used to obtain 10 excision biopsy samples. The parameters were a power of 4.2 W in focused mode and a frequency of 80 Hz in super-pulse mode. The histological analysis was performed with an optical microscope. Computerized imaging software was utilized to quantitatively evaluate the thermal effect in both the epithelium and connective tissue expressed in microns. Results. The thermal effect of the CO2 laser was limited to the surgical resection margins in all the specimens and did not hinder the histological analysis. Thermal artefacts were observed in 3 specimens. The range of thermal effects in the epithelial tissue was between 184 μm and 2,292 μm, while in the connective tissue it was between 133 μm and 2,958 μm. Conclusions. The resulting thermal effects of using a CO2 laser did not hamper the histological evaluation. Utilizing a laser in biopsy procedures should be tailored. Not only should laser parameters and safety margins be taken into consideration but also the working time, clinical accessibility, and the nature and water content of the tissue

Host reaction in paratenic fish hosts against 3rd stage larvae of Anguillicola crassus

Many fish species of Lake Balaton (Hungary) serve as paratenic hosts for the 3rd stage larvae of the eel parasite Anguillicola crassus. The incidence oi different phases of the host reaction varies with paratenic fish host but its nature is basically the same. The appearance of mononuclear cells around the larvae migrating in the tissues or in the abdominal cavity is regarded as a sign of cellular host reaction. The cells adhering to the surface of the larvae gradually assume an epithelioid shape and form a granuloma. With the advancement of the process the larvae and the epithelioid cells surrounding them undergo necrosis, and the granuloma becomes surrounded by a connective tissue capsule. In more chronic cases, the inside of the parasitic nodule surrounded by several layers of connective tissue is filled out by amorphous tissue and parasite debris. In the 'suitable paratenic hosts' Anguillicola sp. larvae not affected by the host's cellular reaction outnumber those affected by it, whereas in the 'less suitable paratenic hosts' the cellular reaction very rapidly forces the larvae into foci and destroys them

Pain in systemic connective tissue diseases

Pain is frequent in patients with connective tissue diseases (CTDs), particularly those affected by systemic sclerosis (SSc) and systemic lupus erythematosus (SLE) in which it is virtually ubiquitous and can have different causes. The SLE classi fi cation criteria include pain associated with musculoskeletal involve- ment, which are frequently the initial symptom of SLE and can include arthralgia, arthritis and/or myalgia. Chronic widespread pain, the cornerstone of fi bromyalgia (FM), is also frequently associated with CTDs. Chronic pain has a considerable impact on mental health, and the professional and family lives of patients. It can be due to many disorders, but there are few reports concerning its prevalence during the course of other diseases. It is essential to identify the origin of pain in CTDs in order to avoid dangerous over-treatment in patients with co-existing widespread pain. Effective pain management is a primary goal of patient care, although it has not been investigated in detail in patients with SSc

Role of growth factors in the pathogenesis of tissue fibrosis in systemic sclerosis.

The most severe clinical and pathologic manifestations of systemic sclerosis (SSc) are the result of a fibrotic process characterized by the excessive and often progressive deposition of collagen and other connective tissue macromolecules in skin and numerous internal organs. The mechanisms involved in the initiation and progression of the remarkable fibrotic process in SSc remain largely unknown. Extensive recent studies have indicated that a variety of polypeptide growth factors play a crucial role in this process. The most commonly implicated growth factors include transforming growth factor beta (TGF-β), connective tissue growth factor (CTGF), platelet derived growth factor (PDGF), and vascular endothelial growth factor (VEGF). Here, the experimental evidence supporting the participation of various growth factors in the pathogenesis of the fibrotic process in SSc and the molecular mechanisms involved will be reviewed

The connective tissue index of Helix aspersa as a metal biomarker

Copyright © 2004, Springer Netherlands.The digestive gland of adult land snails, Helix aspersa, sampled from four different sites in São Miguel island (Azores) was submitted to chemical analyses, autometallography and haemalum/eosin staining, in order to quantify the relative abundance of heavy metals, calcium cells and connective tissue cells. Metals were visualized, through light microscopy, as black silver deposits mostly in the connective tissue cells. Metal levels, essentially of Cu and Fe, were related to the relative volumetric density of connective tissue cells but not to the relative volumetric density of calcium cells from the digestive gland epithelium. Thus, the connective tissue index presented herein is suggested as a biomarker of Cu exposure in terrestrial mollusks.Centro de Investigação em Recursos Naturais (CIRN), University of the Azores

Connective tissue anomalies in patients with spontaneous cervical artery dissection.

OBJECTIVE: To investigate the prevalence of connective tissue abnormalities in patients with spontaneous cervical artery dissections (sCeAD). METHODS: We systematically assessed clinically detectable signs of connective tissue aberration in a series of consecutive patients with sCeAD and of age- and sex-matched patients with ischemic stroke unrelated to CeAD (non-CeAD IS) by a standard examination protocol including 68 items, and performed extensive molecular investigation for hereditary connective tissue disorders in all patients with sCeAD. RESULTS: The study group included 84 patients with sCeAD (mean age, 44.5 ± 7.8 years; 66.7% men) and 84 patients with non-CeAD IS. None of the patients with sCeAD met clinical or molecular diagnostic criteria for established hereditary connective tissue disorder. Connective tissue abnormalities were detected more frequently in the group of patients with sCeAD than in the group of those with non-CeAD IS (mean number of pathologic findings, 4.5 ± 3.5 vs 1.9 ± 2.3; p < 0.001). Eighty-one patients (96.4%) in the sCeAD group had at least one detectable sign compared with 55 patients (66.7%) in the group with non-CeAD IS (p < 0.001). Skeletal, ocular, and skin abnormalities, as well as craniofacial dysmorphisms, were the clinical signs more strongly associated with sCeAD. Signs suggesting connective tissue abnormality were also more frequently represented in patients with sCeAD than in patients with traumatic CeAD (28.6%, p < 0.001; mean number of pathologic findings, 1.7 ± 3.7, p = 0.045). CONCLUSIONS: Connective tissue abnormalities are frequent in patients with sCeAD. This reinforces the hypothesis that systemic aberrations of the connective tissue might be implicated in the pathogenesis of the disease

In vivo characterization of connective tissue remodeling using infrared photoacoustic spectra

Premature cervical remodeling is a critical precursor of spontaneous preterm birth, and the remodeling process is characterized by an increase in tissue hydration. Nevertheless, current clinical measurements of cervical remodeling are subjective and detect only late events, such as cervical effacement and dilation. Here, we present a photoacoustic endoscope that can quantify tissue hydration by measuring near-infrared cervical spectra. We quantify the water contents of tissue-mimicking hydrogel phantoms as an analog of cervical connective tissue. Applying this method to pregnant women in vivo, we observed an increase in the water content of the cervix throughout pregnancy. The application of this technique in maternal healthcare may advance our understanding of cervical remodeling and provide a sensitive method for predicting preterm birth

The Effect of EDTA in Attachment Gain and Root Coverage

Root surface biomodification using low pH agents such as citric acid and tetracycline has been proposed to enhance root coverage following connective tissue grafting. The authors hypothesized that root conditioning with neutral pH edetic acid would improve vertical recession depth, root surface coverage, pocket depth, and clinical attachment levels. Twenty teeth in 10 patients with Miller class I and II recession were treated with connective tissue grafting. The experimental sites received 24% edetic acid in sterile distilled water applied to the root surface for 2 minutes before grafting. Controls were pretreated with only sterile distilled water. Measurements were evaluated before surgery and 6 months after surgery. Analysis of variance was used to determine differences between experimental and control groups. We found significant postoperative improvements in vertical recession depth, root surface coverage, and clinical attachment levels in test and control groups, compared to postoperative data. Pocket depth differences were not significant (P\u3c.01)

Cardiac Specific Gene Expression Changes in Long Term Culture of Murine Mesenchymal Stem Cells

Murine MSCs are a readily available source of adult stem cells enabling extensive in vitro study of this cell population. MSCs have been described as multipotent, and have been proven capable of differentiation into several connective tissue types. Furthermore some studies have suggested an ability to differentiate into non-connective tissue cell types such as the cardiomyocyte. The aim of this study was to differentiate murine MSCs toward cardiac lineage with the commonly used method of culture with 5’ Azacytidine. Critically, baseline analysis of gene expression of passage four MSCs demonstrated expression of key cardiac markers including cardiac troponin T and I, and the ryanodine receptor. Furthermore, expression analysis of these genes changed with time in culture and passage number. However, there was no significant alteration when cells were subjected to a differentiation protocol. This study therefore highlights the importance of analyzing baseline cells extensively, and indicates the limitations in extrapolating data for comparison between species. Furthermore this data brings into question the efficacy of cardiac differentiation using MSCs