Light and electron microscopy of skeletal muscle tissues of patients versus carriers of duchenne muscular dystrophy

The study included 8 male patients [5 - 10 years old]. With Duchenne muscular dystrophy [DMD], their female carriers [20 - 50 years old] and 3 healthy volunteers [2 males and 1 female, 20 - 40 years old]. Carriers were classified into obligate symptomatic [4 carriers], obligate asymptomatic [2 carriers] and possible carriers [2 carriers]. Muscle biopsy was taken from the quadriceps muscle of all the studied persons and prepared for both light and electron microscopy processes. Light and electron microscopy of muscle biopsies revealed marked dystrophic changes in all patients and mild dystrophic changes in 2 obligate symptomatic carriers, while some ultrastructural changes were detected by electron microscopy only in the other 2 obligate symptomatic carriers and one of the 2 obligate asymptomatic carriers. The other obligate asymptomatic carrier and the possible carriers showed no changes by both light and electron microscopy. So, we can conclude that carriers of DMD might show dystrophic changes by both light and electron microscopy. These changes were more frequent in obligate symptomatic carriers. Although, electron microscopy was more accurate than light microscopy in their detection, it could not detect all the carrier state

Immunohistochemical detection of laminin in various breast lesions

The distribution of laminin, a structural glycoprotein specific for basement membranes, was studied in 52 breast lesions with antilaminin and the avidin-biotin peroxidase complex method. Laminin was observed within vascular and epithelial basement membranes. It displayed a continuous linear pattern in normal breast tissue, fibrocystic disease and in benign tumors. In malignant tumors, laminin was heterogeneously distributed, with a discontinuous linear pattern. No intracellular laminin staining was detected. Laminin may be a valuable aid in the differentiation between benign and malignant breast lesions. Absence of basement membrane and lack of the linear pattern of laminin at the boundaries of malignant ducts may be of value in exclusion of carcinoma in situ

Immunohistochemical studies on patterns of fibronectin and collagen type IV in normal human liver and hepatocellular carcinoma

The distribution of fibronectin [FN] and collagen type IV [coll IV] which are two main components of the basement membrane [BM], was investigated in normal human liver and hepatocellular carcinoma [HCC]. The peroxidase antiperoxidase [PAP] method was applied on paraffin embedded pepsin treated tissue, and the pattern of distribution of the two antigens was compared with the grade of differentiation of the tumor. Fibronectin was observed both extracellularly and intracellularly. It was either increased or decreased. In the more differentiated tumors, fibronectin was increased and it consisted of thin or thick stands. It was either periglandular, pericellular, sinusoidal or stromal-vascular. Decreased fibronectin was seen in undifferentiated HCC. Collagen type IV was localized only extracellularly. It exhibited two patterns of distribution in HCC, peritrabecular or periacinar and stromal-vascular. The finding that FN can be located pericellularly or within the acini supports the concept that FN is synthesized, at least in part by hepatoma cells. The peritrabecular and periacinar location of coll IV suggested a sinusoidal cell derivation of this antigen. The immunohistochemical staining pattern for BM in HCC reflects the differentiation of the tumor, with differentiated tumors showing a relatively intact BM and poorly differentiated tumors revealing a sharply defective BM