Histological Characteristics

The earliest histological feature is proliferation of Langerhans cells found around terminal and respiratory bronchioles (3,21). These early cellular lesions expand to form nodules that are typically 1 to 6 mm in diameter (21). These bronchiolo-centric nodules characteristically have a stellate configuration (Fig. la). The morphology of the nodules varies with the activity of the lesions. Early lesions are cellular. The peribronchiolar interstitium and adjacent alveolar septa are thickened by clusters of Langerhans cells admixed with variable numbers of eosinophils, neutrophils, lymphocytes, macrophages, and fibroblasts. Eosinophils are often numerous and can form eosinophilic abscesses but may be absent in up to 20% of 

In advanced lesions, fibroblastic proliferation develops in the center of the nodules and is followed by collagen deposition. This results in central scarring with peripheral cellularity. Ultimately, the nodules become completely scarred with scant inflammatory cells and no diagnostic Langerhans cell (21). Paracicatricial 

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Polyvidone (polyvinylpyrrolidone, povidone) is a variable-weight polymer of the monomer N-vinylpyrrolidi-none. When it enters the body it causes histologically characteristic reactions in tissues with which it comes into contact (1,2). 

Shimizu T (2005) Histological characteristics of mandible in fetal mice. J Hard Tissue Biol. 14 67-68. 

Dysplastic lesions Due to changes in the cytoplasm or the nucleus, dysplastic lesions exhibit histological characteristics such as irregular structure or growth. Genetic factors are considered to be involved (even though appropriate criteria do not as yet exist for all forms). (53) The lesions are classified as follows (s. tab. 21.4) ... 

A spectrum of cutaneous lesions has been described distant from sites of interferon alfa injection. The clinical and histological characteristics of inflammatory skin lesions that occurred away from injection sites have been investigated in 20 patients treated with interferon alfa-2a or 2b plus ribavirin for chronic hepatitis C (299). Cutaneous lesions developed between 2 weeks and 4 months and consisted of pruritic papular erythematous eruptions with occasional vesicles. These eczema-like skin lesions predominated on the distal limbs, the head, and the neck. Photosensitivity was also noted in four patients and mucous lesions in two. Skin biopsy mostly showed non-specific mononuclear infiltrates. The skin lesions were promptly reversible in 10 patients who required treatment withdrawal, while others improved after symptomatic treatment. Two of the three patients who again received the same or another type of interferon alfa had recurrence of their lesions. Skin tests performed in six patients were negative, including the two patients who relapsed after rechallenge with interferon alfa, and were therefore considered unhelpful. 

Tacrolimus nephrotoxicity has been reviewed (68) and is considered to be very similar to that described with ciclosporin. The clinical and histological characteristics of acute tacrolimus nephrotoxicity have been described from a retrospective analysis of 67 patients with renal transplants, of whom 27 developed acute nephrotoxicity, in seven of whom underljdng moderate-to-severe renal arteriosclerosis might have predisposed to tacrohmus nephrotoxicity (69). 

Histology of the Indian Com Seed With fruit wall attached).—If a longitudinal section be cut through the lesser diameter of a soaked grain, the following histologic characteristics will be observed ... 

PSSM is inherited as an autosomal recessive trait and is probably caused by a defect in glucose metabolism within the muscle cell (De La Corte et al 1999a,b). EPSM has similar histological characteristics to PSSM. However, a syndrome of... 

Myers R, Cerini R, Sayegh R, Moreau R, Degon C, Lebrec D, et al. Cardiac hepatopathy Clinical, hemodynamic, and histologic characteristics and correlations. Hepatology 2003 37 393-400. 

Overall, studies aimed at developing better prognostic markers in phyllodes tumors have suffered from low sample size, a lack of patient follow-up data, and lack of reproducibility. The most significant consistently reported variables in the prediction of phyllodes tumor behavior remain histologic characteristics, in particular the presence of stromal overgrowth and adequate surgical resection margins. 773-279... 

Koschier (1999) reviewed the potential of dermal exposure to kerosene to cause adverse health effects. The author described a study in which rats were exposed to hydrodesulfurized kerosene dermally at 0,165, 330, and 495 mg/kg for 5 days/wk for 13 wk. The rats were assessed with a FOB, and motor activity, startle response, and histologic characteristics were measured. All groups were examined after the 13-wk exposure, and the control and high-dose groups were also examined after a 4-wk recovery period. No significant differences were observed in any of the measures in any of the exposure groups. 

Recent studies of the brains of transsexual men reveal that an important old brain structure involved in sexual behavior has in these men the same histological characteristics as the structure found in females.7 The characteristics are not influenced by hormones found in the adult. It seems that gender identity, like sexuality, develops as a result of an interaction between the developing brain and sex hormones. 

Noguchi, S., Aihara, T, Motomura, K. et al. (1996) Histologic characteristics of breast cancers with occult lymph node metastases detected hy keratin 19 mRNA reverse-transcriptase polymerase chain reaction. Cancer, 78, 1235—1240. 

Table 1. Comparison of volumes and histological characteristics of the vomeronasal epithelium between human fetal and adult samples...

Teifke A, Behr O, Schmidt M et al (2006) Dynamic MR imaging of breast lesions correlation with microvessel distribution pattern and histologic characteristics of prognosis. Radiology 239 351-360... 

The pathogenesis of primary myxedema is not always easy to trace except when hypothyroidism follows thyroidectomy or massive necrosis of the thyroid. Autoimmune reactions probably are at least in some cases responsible for thyroid destruction. In myxedema, the thyroid is usually small and hard. Histologically, the typical follicular pattern has disappeared and is replaced by fibrosis. The thyroid is goitrous in a few cases, and presents the histological characteristics of hyperplasia. 

Histological characteristics of calciphylaxis include small-vessel calcifications of the skin, subcutaneous tissue and visceral organs. These vascular changes promote tissue ischemia that often results in tissue necrosis. 

The search for the site(s) of auxin transport has followed three main lines (1) transport experiments using tissues of differing anatomical-histological characteristics (2) macro- and microautoradiographic studies of tissue transporting auxin and (3) analyses of membrane fractions with specific binding properties. 

Although an etiologic classification is useful for reminding the physician when to suspect the presence of bronchiolitis, the more convenient classification scheme is based on histologic characteristics as the histologic patterns generally show a better correlation with the radiologic manifestations, the natural history of disease, and the response to therapy. 

Katz ME, Karlowicz MG, Adelman RD, Werner AL, Solhaug MJ (1994) Nephrocalcinosis in very low birth weight neonates sonographic patterns, histologic characteristics, and clinical risk factors. J Ultrasound Med 13 777-782 Kopp N, Leumann E (1995) Changing pattern of primary hyperoxaluria in Switzerland. Nephrol Dial Transpl 10 2224-2227... 

Itoh Y, Akamatsu K (1998) Relationships between echo level and histologic characteristics in small hepatocellular carcinomas. J Clin Ultrasound 26 295-301 Kim KW, Kim TK, Han JK, et al (2000) Hepatic hemangiomas spectrum of US appearances on gray-scale, power Doppler, and contrast-enhanced US. Korean J Radiol 1 191-197 Kim TK, Kim AY, Choi BI (2002) Hepatocellular carcinoma harmonic ultrasound and contrast agent. Abdom Imaging 27 129-138... 

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