SEARCH · Search PubMed

Results for “HYPERPLASIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 559 records · Page 31Linked to original sources

PubMed1976

Small-bowel resection. Oral intake is the stimulus for hyperplasia.

Small-bowel resection leads to hyperplasia of the residual small intestine, However, the factors initiating small-bowel hyperplasia are not clearly understood, although oral intake either by direct contact with the small bowel or via hormonal or neurovascular factors has been suggested as the major stimulus. In order to determine whether oral intake is an obligatory prerequisite for small-intestinal hyperplasia, we compared rats one week after undergoing a 70-cm proximal intestinal resection with sham-operated animals. Resected, orally fed rats demonstrated small-intestinal hyperplasia, whereas resected and sham-operated intravenously alimented rats did not. There were no differences in gut weight, mucosal weight, mucosal protein, or DNA between resected or sham-operated intravenously alimented rats. These data provide direct experimental proof that oral intake is a necessary stimulus for small-intestinal hyperplasia after resection.

Animals↗

PubMed1977

Medullary thyroid carcinoma and pheochromocytoma accompanied with nodular hyperplasia in multiple endocrine neoplasia type 2.

Three patients with familial multiple endocrine neoplasia type 2 underwent total adrenalectomy and subsequently near-total or total thyroidectomy. The overt pheochromocytomas were present bilaterally in two patients and unilaterally in another patient. In addition, multiple nodules measuring a few mm in diameter were demonstrated in all adrenal medullas examined. All patients exhibited bilateral medullary thyroid carcinomas which varied in size from a few minute nodules accompanied by the microscopic C-cell hyperplasia to distinct large tumors. The thyroid C-cell hyperplasia appeared to be confined to the upper and middle thirds of the lateral lobe, and micronodules of the C-cell hyperplasia enlarged to coalesce, forming one large carcinoma mass. On the other hand, nodular hyperplasia of the chromaffin cells was distributed diffusely throughout the adrenal medulla and each nodule appeared to develop individually into a large pheochromocytoma. These findings suggested that, at least in the family members at a high risk for multiple endocrine neoplasia type 2, the development of both medullary thyroid carcinoma and pheochromocytoma was always preceded by a multicentric nodular hyperplasia. On the basis of the pathogenesis of these tumors, the most rational surgical approach was presented.

Adrenal Gland Neoplasms↗

PubMed1998

Relationship between prostate specific antigen density, microvessel density and prostatic volume in benign prostatic hyperplasia and advanced prostatic carcinoma.

The aim of this study was to investigate the relationship between prostate specific antigen density and prostate volume with microvessel density in patients with benign prostatic hyperplasia and advanced prostatic carcinoma. Sixty-eight patients with benign prostatic hyperplasia and 11 patients with advanced prostatic carcinoma participated in the study. The paraffin blocks of all patients were stained with CD34 by the standard immunohistochemical technique and microvessel density, prostate specific antigen density and prostatic volume were determined. In patients with benign prostatic hyperplasia the mean microvessel density, mean prostate specific antigen density and mean prostatic volume were 74+/-89+/-22.73, 0.12+/-0.10 and 59.97+/-27.0 ml, respectively. There was no correlation between prostate specific antigen density and mean prostatic volume or microvessel density (r = 0.079 and -0.095, respectively). In patients with advanced prostatic carcinoma the mean microvessel density, mean prostate specific antigen density and mean prostatic volume were 147.90+/-47.55, 0.63+/-0.41 and 54.00+/-22.42 ml, respectively. In this group, while there was a good correlation between prostate specific antigen density and microvessel density (r = 0.785), no significant correlation was found between prostatic volume and microvessel density (r = -0.07). There was significant statistical difference in patients with advanced prostatic carcinoma compared to patients with benign prostatic hyperplasia in terms of mean microvessel density (p<0.0001). The findings that there was no correlation between prostatic volume and MVD either in benign prostatic hyperplasia or in prostatic carcinoma suggest that microvessel development is not correlated with prostatic volume but may be correlated with morphology.

Aged↗

PubMed2002

Adrenal cortical and medullar hyperplasia--a retrospective analysis of 6 cases.

The features of the symptoms, laboratory tests and pathological characteristics of adrenal cortical and medullary hyperplasia were studied. In 6 cases of hypercatecholaminenia, plasma norepinephrine (NE), epinephrine (E), catecholamine (CA) and 24-h urinary vanillylmandelic acid (VMA), 17-hydroxycorticosteroid (OHCS) and 17-ketosteroid (KS) were determined. Adrenal glands were examined by CT scan and 131I-MIBG imaging. Pathological examination was performed after operation. The results showed that in 6 cases of hypercatecholaminenia (3 men and 3 women) aged from 34-50 years, the clinical features were just like "pheochromocytoma", for example, episodic headache, perspiration, palpitation, pallor, apprehension, nausea, tremor, anxiety and so on. Plasma levels of CA, NE and E were elevated in all 6 cases. 24-h urinary samples obtained at the onset revealed elevated VMA in 1 case. 24-h urinary cortisol was obviously elevated in all 6 cases. 24-h urinary 17-OHCS, 17-KS was normal. B-type ultrasound, CT, MRI and 131I-MIBG revealed 9 lateral adrenal gland diffuse or nodular enlargement in 6 cases. Pathologic examination showed adrenal cortical and medullary hyperplasia. Clinically, adrenal cortical and medullary hyperplasia resembled "pheochromocytoma". The most significant feature of this disease was both elevated plasma CA and 24-h urinary cortisol obviously. Pathologic examination showed adrenal cortex nodular hyperplasia and medullar diffuse or limit hyperplasia. Whether it is an independent disease or symptoms of the other disease has not final conclusion up till now.

Adrenal Cortex↗

PubMed1997

Idiopathic hyperplasia of the adrenal gland behaving like an aldosterone producing adenoma.

Primary hyperaldosteronism (adrenal adenoma and idiopathic hyperplasia) is a disorder with hypertension, hypokalemia, elevated serum aldosterone and suppressed plasma renin activity. Hyperplasia is managed medically whereas adenomas are treated surgically. Selective adrenal venous catheterization and aldosterone measurement is a useful tool in making the distinction in 95% of cases. We report a case of bilateral idiopathic hyperplasia of the adrenal glands adequately treated with medications for 6 years followed by worsening. Selective catheterization was consistent with a right sided adenoma. Surgical removal of the right adrenal gland alleviated her symptoms. Pathological examination showed focal nodular hyperplasia. We propose that in the course of the disease the focal hyperplastic nodule became autonomous and behaved like an adenoma. Monitoring of patients with adrenal hyperplasia for recurrence of symptoms is prudent as surgery is beneficial in patients who develop an autonomous nodule.

Adenoma↗

PubMed2003

[Hyperplasia of the thyroid gland].

Hyperplasia of the follicular epithelium (goitre) is the most common morphological change in the thyroid seen by the pathologist. The present paper deals with the aetiology, epidemiology and clinical features of thyroid hyperplasia and its differential diagnosis from thyroid adenoma. Neoplastic hyperplasia of the calcitonin-producing thyroid C cells gives rise to familial medullary carcinoma. The second part of the paper deals with the definition of neoplastic C cell hyperplasia and its discrimination from physiological C cell hyperplasia.

Humans↗

PubMed2001

Natural history of endometrial hyperplasia. Study of 77 patients.

Seventy-seven patients with endometrial hyperplasia, 48 with simple hyperplasia without atypia (SH), 17 with complex hyperplasia without atypia (CH), one with simple hyperplasia with atypia (SHA), and 11 with complex hyperplasia with atypia (CHA) were prospectively followed-up by total curettage every 12 months for 3 years. Progression to carcinoma occurred in only one of the 77 patients; she showed grade 1 adenocarcinoma. The overall regression rates were 79% for SH, 100% for SHA, 94% for CH, and 55% for CHA, respectively. In patients with CHA whose disease reverted to normal endometrium, regression was most likely to occur within the first year.

Adenocarcinoma↗

PubMed2001

Hepatocellular carcinoma associated with focal nodular hyperplasia. Report of a case with clonal analysis.

We describe a hepatocellular carcinoma partially surrounded by focal nodular hyperplasia in a 65-year-old female patient. In order to clarify the relationship of the hepatocellular carcinoma and the adjacent focal nodular hyperplasia, clonal analysis was conducted. The clonal analysis was based on the methylation pattern of the polymorphic X-chromosome-linked androgen receptor gene (HUMARA). The allelic bands from the amplification of the focal nodular hyperplasia and of the hepatocellular carcinoma showed a significant reduction in the intensity of one of the two alleles as compared with two alleles of equal intensity in the buff coat after HhaI digestion, which indicated that these two parts were monoclonal. However, the inactivated allele in the focal nodular hyperplasia and that in the hepatocellular carcinoma were not identical. Therefore, the focal nodular hyperplasia and hepatocellular carcinoma probably derived from the clonal expansion of two different clones.

Aged↗

PubMed2001

Prognostic aspects on endometrial hyperplasia and neoplasia.

There are various forms of endometrial hyperplasia which, in terms of prognosis and therapy, can be subdivided into those having cytological atypia and those lacking this feature. The former may progress into invasive endometrial malignancy through a transitional non-invasive stage. This is a continuous process and, as a result, the distinction between an atypical hyperplasia and an intraepithelial adenocarcinoma (IEA) or an adenocarcinoma with stromal invasion is not histologically reproducible. The concept of endometrioid neoplasia, which includes the entire spectrum of the aforementioned proliferating endometrial lesions, was introduced. Adenocarcinomas arising from an atypical hyperplasia are invariably of the endometrioid cell type, whereas those developing from an atrophic endometrium may be either of the endometrioid or of the non-endometrioid cell type. Endometrioid adenocarcinomas arising through the hyperplasia-neoplasia sequence are oestrogen induced and tend to be well differentiated and less invasive of the myometrium, lack lymphatic and metastatic involvement and have an excellent prognosis. Oestrogen-induced adenocarcinomas are also endometrioid, arising from an atrophic or a rather weakly proliferating endometrium, but these neoplasms are frequently of higher histological grade and have a somewhat less favourable prognosis. Finally, endometrial carcinomas of the non-endometrioid cell type, mainly serous papillary and clear cell carcinomas, are non-oestrogen induced, non-hyperplasia associated and show adverse aggressive histological features and an extremely poor prognosis. The antigenic characteristics and the molecular events associated with the development of these forms of endometrial malignancy are distinct and allow the description of, at least, two pathogenetic types of endometrial carcinoma.

Biomarkers, Tumor↗

PubMed2005

Spontaneous rupture and hemorrhage of hepatic focal nodular hyperplasia in lobus caudatus.

In general, focal nodular hyperplasia lesions of the liver have a benign natural course; the majority of cases remain asymptomatic and complications are rare. We report a case of spontaneous rupture and hemorrhage of focal nodular hyperplasia, which is extremely rare in the literature. A 35-year-old woman was admitted with severe upper abdominal pain and unstable hemodynamic status. No major abdominal trauma was noted. Radiology findings suggested a diffuse hemoperitoneum. Emergent surgical exploration showed a hemoperitoneum due to the rupture of a hepatic mass lesion in segment I. Suture of the rupture was undertaken with success. After this lifesaving emergent surgery, further investigations, including ultrasound, contrast-enhanced computed tomography, and magnetic resonance imaging, were undertaken, and a 5.7 x 9.8 x 6.4-cm focal nodular hyperplasia lesion was identified in segment I. Two weeks after the first surgical hemostasis, surgical removal of segment I, including the mass, was performed. The postoperative course was uneventful. Pathological evaluation confirmed the nature of focal nodular hyperplasia. The patient remains asymptomatic without evidence of recurrence 3 years and 6 months after surgery. To our knowledge, this is the firstcase of spontaneous rupture and hemorrhage of focal nodular hyperplasia that needed two consecutive surgical operations.

Adult↗

PubMed2005

Long-term inhibition of intimal hyperplasia using vascular photodynamic therapy in balloon-injured carotid arteries.

Flexible treatments for intimal hyperplasia after angioplasty are still needed. The aim of this study was to demonstrate the long-term effects of vascular photodynamic therapy with talaporfin sodium on intimal hyperplasia following interventional injury. Intimal hyperplasia was induced by balloon distension injury to the carotid artery in 31 rabbits. Talaporfin, 5.0 mg/kg, was delivered systemically immediately after balloon injury. The injury site was irradiated with a diode laser light of wavelength 664 nm using a fluence of 50 J/cm2 after 30 min. At day 3 and weeks 3, 6, 9, 15, and 25 after photodynamic therapy, the treated artery of each rabbit was excised and examined immunohistochemically. Thirty minutes after talaporfin administration, drug fluorescence was found only in the balloon-injured carotid artery wall. At 3 days, no smooth muscle cells were seen in the media of the photodynamic therapy-treated arterial segments. Intimal hyperplasia developed progressively in the balloon-injured and untreated segments; however, in the segments treated with photodynamic therapy, intimal hyperplasia was markedly suppressed until 25 weeks and the media was repopulated by smooth muscle cells without macrophages. Vascular photodynamic therapy with talaporfin may be used to inhibit restenosis after vascular intervention.

Actins↗

PubMed1990

Pseudogene/functional gene ratio in late-onset 21-hydroxylase-deficient adrenal hyperplasia.

Late-onset adrenal hyperplasia caused by 21-hydroxylase deficiency leads to hyperandrogenic symptoms in 1% to 6% of hyperandrogenic women. Normally there are two 21-hydroxylase genes present in a 1:1 ratio. Gene CYP21A is a nonfunctional pseudogene, whereas CYP21B is an active gene. Abnormalities of the CYP21A/CYP21B gene ratio may serve as a marker for late-onset adrenal hyperplasia. Eight hyperandrogenic patients with late-onset adrenal hyperplasia and five control subjects were studied by evaluation of autoradiograms of Taq I and Kpn I digests by means of laser densitometry. Seven of eight (87%) patients with late-onset adrenal hyperplasia had an abnormal CYP21A/CYP21B gene ratio on laser densitometry, suggestive of CYP21A gene duplication, CYP21B gene deletion, or the conversion of a CYP21B gene to a CYP21A gene. One of the five control subjects had a heterozygous deletion of the CYP21A gene. The CYP21A/CYP21B gene ratio may serve as a useful genetic marker for late-onset adrenal hyperplasia in a non-high-risk population.

Adrenal Glands↗

PubMed1984

Hyperplasia of pancreatic duct epithelium produced by exposure to sodium deoxycholate.

Severe epithelial hyperplasia was produced in a canine model by the perfusion of the main pancreatic duct with 15 mM of deoxycholate at rates as low as 1.5 ml/day in 6 to 14 days. At higher rates (5 ml/day) deoxycholate caused complete epithelial cell lysis in the duct closest to the tip of the cannula with hyperplastic changes downstream from this section. Perfusion with a buffer solution alone and cannulation alone produced none of these changes in similar duct segments. No hyperplasia was seen in the upstream cannula obstructed duct, even in the presence of severe atrophy. Long-term (81 days) perfusion with 3 mM of deoxycholate at 3 ml/day resulted in more severe hyperplasia that still appeared benign. When glycine-conjugated deoxycholate was perfused through the duct, hyperplasia but no cell lysis was seen. In vitro, deoxycholate caused epithelial cell lysis in pancreatic duct fragments at concentrations of 0.5 mM and above. The results of this study suggest that secondary bile salts or other similar surface-active cytotoxic agents present in the biliary tree or duodenum may play a more important role in the pathogenesis of pancreatic ductal epithelial hyperplasia associated with pancreatic cancer than ductal obstruction.

Animals↗

PubMed1990

Evolution of fundic argyrophil cell hyperplasia in nonantral atrophic gastritis.

Fundic argyrophil cells were studied for a mean period of 68.7 months (range, 11-170) in 18 patients with fundic atrophic gastritis and achlorhydria. Initially, 12 patients had hyperplasia of the argyrophil cells, the severity of which was assessed using a semiquantitative classification based on the number of argyrophil clusters per square millimeter. At the end of the study, the degree of hyperplasia was unchanged in 9 patients, had decreased in 2, and had increased in 1; no significant increase in the number of argyrophil clusters, precarcinoid changes, or carcinoid tumors were observed and the high level of gastrinemia [mean, 4.8 (range, 1.9-8.1) times the upper limit for normal) did not change significantly. Of the 6 patients with no hyperplasia at the outset of the study, 4 continued without hyperplasia and 2 presented a low-grade hyperplasia at the 20th and 130th month. Gastrinemia increased significantly in the last patient and stayed normal in the other 5. This study argues in favor of the stable appearance of fundic argyrophil cells in patients with atrophic gastritis and stable gastrinemia.

Achlorhydria↗

PubMed1991

The role of androgens in the late-premenopausal woman with adenomatous hyperplasia of the endometrium.

To examine the possible role of androgens in hyperplasia of the endometrium, the concentrations of testosterone (T), androstenedione (A), dehydroepiandrosterone sulfate (DHEA-S), sex hormone-binding globulin (SHBG), estradiol (E2), follicle stimulating hormone (FSH) and luteinizing hormone (LH), were measured in peripheral venous serum obtained from 42 premenopausal women with adenomatous hyperplasia of the endometrium (group A) and from 18 women without hyperplasia (group B). In patients with hyperplasia of the endometrium, significantly higher peripheral venous concentrations were found for all androgens (P less than 0.05) and estradiol (P less than 0.001) than in control patients. In contrast, there was no statistically significant difference in the mean serum values of SHBG as well as in gonadotropins among the population of compared groups. We conclude that apart from the increased estrogenic activity in patients with adenomatous hyperplasia of the endometrium, androgens may play a significant role.

Androgens↗

PubMed1994

Massive thymic hyperplasia: characterization of a rare mediastinal mass.

Thymic hyperplasia is a rare cause of an anterior mediastinal mass in children. True thymic hyperplasia is characterized by massive thymic hypertrophy with retention of normal thymic architecture, and must be distinguished from more commonly seen tumors of the anterior mediastinum. Previous reports of thymic hyperplasia primarily have been descriptive, with minimal analysis of the cellular characteristics of the tumor. To better describe the cellular characteristics of thymic hyperplasia, the authors report on a 10-year-old boy found to have an asymptomatic left paracardiac mass during cardiac evaluation. The mass enlarged rapidly during the following 2 weeks and filled the entire left side of the chest. An open biopsy specimen showed normal thymic architecture. Because of the size and rapid growth of the mass, the authors decided to resect it. Cellular analysis of the mass did not show differences from normal thymic elements. There was conserved thymic architecture. The expression of cell surface markers and the proliferative response of thymocytes to cytokines appeared to be normal. Similarly, a long-term cell culture of the thymocytes did not result in clonal proliferation. Immunohistologic staining of stromal cells showed no striking differences from normal thymic elements. Moreover, immunologic analysis of the patient by standard hematological parameters, lymphocyte subsets, quantitative immunoglobins, and immunoelectrophoresis showed no abnormalities except for lymphocytosis, which resolved after tumor resection. The authors conclude that thymic hyperplasia occurs in immunologically normal children and may exhibit (1) rapid growth with minimal associated symptoms, (2) normal thymic architecture, (3) normal thymocyte and stromal growth characteristics in vitro, and (4) a normal thymocyte response to cytokine stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗

PubMed1991

Neuroendocrine cell hyperplasia and neuroendocrine carcinoma of the rodent fundic stomach.

Certain substances when given orally to rats have effects on the neuroendocrine cells of the fundic stomach. Such compounds also have effects on acid or its secretion, which is to a greater or lesser extent suppressed, with a consequent rise in serum gastrin, followed by an increase in the number of histamine-secreting ECL cells. These changes are seen with the histamine H2 receptor antagonists loxtidine, SKF 93479, ICI 162,846 and ranitidine; with the hypolipidaemic agents clofibrate, ciprofibrate and benzofibrate; with sodium bicarbonate and pentagastrin; and with omeprazole, a potent inhibitor of the parietal cell proton pump mechanism. Changes in the pH of the rat stomach stimulate the neuroendocrine G cells of the pylorus to secrete gastrin, which acts on the ECL cells of the fundus causing the production of histamine, which in turn stimulates the parietal cell. This sequence leads to an excess of circulating gastrin, which is detectable within 5 days. Subsequently increases in the number of ECL cells occur, the hyperplasia being related to hypergastrinaemia and the degree of acid suppression. The hyperplastic response is rapid, being so obvious with loxtidine at 39 days that there is good reason to suppose it could well be detected earlier. Using omeprazole, hyperplasia was found at 28 days after oral doses of 140 mg/kg/day. In order to get an equivalent degree of acid suppression with ranitidine it was necessary to deliver 420 mg/kg/day by subcutaneous infusion using an osmotic minipump, when hyperplasia occurred. Interestingly, only omeprazole produced a hyperplastic response of G cells. Such results reflect the covalent binding of omeprazole to the proton pump as opposed to the competitive binding of ranitidine to the histamine H2 receptor site. In addition to ECL cell hyperplasia there is ample evidence from lifetime studies in rats and mice that neoplasia may result. Neuroendocrine carcinomas (carcinoids) of the rat fundic stomach have been observed with loxtidine, omeprazole, SKF 93479 and ICI 162,846. They are seen late in the 2-year rat studies and are most unlikely to have arisen purely as an extension of the hyperplastic response. It is possible that the prolonged disturbance of gastric homoestasis resulting from achlorhydria result in the production of a carcinogen or carcinogens, in which event it is not too surprising, in view of the neuroendocrine hyperplasia, that the tumours seen are neuroendocrine carcinomas.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed1988

Combined thyrotroph and lactotroph cell hyperplasia simulating prolactin-secreting pituitary adenoma in long-standing primary hypothyroidism.

Primary hypothyroidism accompanies more than 50% of clinically significant pituitary thyrotroph adenomas. Hypothyroidism may also produce pituitary enlargement secondary to thyrotroph hyperplasia and present with a sellar mass and hyperprolactinemia. Three hypothyroid patients who presented with presumed prolactin-producing adenomas are reported. Although laboratory and radiologic abnormalities of pituitary enlargement may resolve after corrective thyroid therapy, our patients showed no such response and underwent operation. Histologic examination revealed no adenomas, but thyrotroph and lactotroph hyperplasia were present. Thyrotroph hyperplasia probably results from lack of negative feedback of thyroid hormone upon the anterior pituitary. Whether this is due to hypothalamic release of thyrotropin-releasing hormone (TRH) or another mechanism is unclear. Lactotroph hyperplasia may result from excess TRH, which stimulates lactotrophs with resultant hyperprolactinemia, or from reduced hypothalamic dopamine, thereby facilitating prolactin secretion. This study suggest that (a) hyperprolactinemia in hypothyroidism is not necessarily due to the "stalk section effect" secondary to pituitary enlargement, and (b) patients with primary hypothyroidism and sellar mass should initially be managed medically so that potentially reversible pituitary hyperplasia is not mistaken for adenoma.

Adenoma↗