The possible involvement of virus in breast cancer

It is well known that the etiology of human breast cancer is significantly affected by environmental factors. Virus-associated cancer refers to a cancer where viral infection results in the malignant transformation of the host’s infected cells. Human papillomaviruses (HPV), mouse mammary tumor virus (MMTV) and Epstein–Barr (EBV) virus are prime candidate viruses as agents of human breast cancer. The precise role that viruses play in tumorigenesis is not clear, but it seems that they are responsible for causing only one in a series of steps required for cancer development. The idea that a virus could cause breast cancer has been investigated for quite some time, even though breast cancer could be a hereditary disease; however, hereditary breast cancer is estimated to account for a small percentage of all breast cancer cases. Based on current research, this review present at moment, substantial, but not conclusive, evidence that HPV, EBV and MMTV may be involved in breast cancer.     

Cardiac involvement in hypertension

Despite improved patient detection and pharmacologic therapy, the effect of treatment of hypertension on mortality from coronary artery-related events remains unresolved. Left ventricular (LV) hypertrophy, a known consequence of hypertension, is associated with an excess mortality independent of other known cardiovascular risk factors. Recently, LV hypertrophy accompanying hypertension has been associated with ominous ventricular arrhythmias. However, it does not necessarily follow that regression of LV hypertrophy will reduce this increased mortality. Diastolic dysfunction, manifested by reduced ventricular distensibility of the hypertrophying left ventricle, appears to be an early characteristic of the hypertensive heart since echocardiographic techniques have demonstrated diastolic filling abnormalities in untreated essential hypertensives even before significant LV hypertrophy appears. Not all antihypertensive agents diminish LV mass and improve diastolic dysfunction. Certain sympatholytic agents, calcium antagonists, β-adrenergic blockers, and the angiotensin-converting enzyme inhibitors appear to diminish LV hypertrophy. However, future studies are needed to determine if these agents that appear to reverse findings of LV hypertrophy and improve diastolic dysfunction will also reduce risk of coronary artery disease and related events.     

The pulmonary involvement in portal hypertension: portopulmonary hypertension and hepatopulmonary syndrome

Pulmonary abnormalities are common in patients with advanced chronic liver disease. Two distinct syndromes strictly related to the presence of portal hypertension, but clearly different from a pathophysiologic point of view, have been identified. Portopulmonary hypertension, characterized by an increased pulmonary arterial pressure, is due to a progressive arteriolar vasoconstriction induced by excess local production of vasoconstrictor substances. Hepatopulmonary syndrome results from intrapulmonary microvascular dilation caused by an inadequate synthesis or metabolism of putative pulmonary vasoactive substances leading to a functional vasodilation of the pulmonary vasculature, ultimately leading to hypoxemia. Controversies on pathogenesis imply different tentative therapeutic approaches for the medical management of these conditions. The development of portopulmonary hypertension or the hepatopulmonary syndrome has important clinical and prognostic implications facing the impact of new therapeutic strategies for the management of the main complications of advanced liver diseases on cardiopulmonary function.     

Neonatal androgenization increases vasoactive intestinal peptide levels in rat anterior pituitary: possible involvement of vasoactive intestinal peptide in the neonatal androgenization-induced hyperprolactinemia.

Accumulating evidence suggests that vasoactive intestinal peptide (VIP) may be a physiological PRL-releasing factor. In the present study, we examined a possible involvement of VIP in the neonatal androgenization (NA)-induced hyperprolactinemia. Twenty-four hours after birth, newborn female rats were injected sc with 1,000 micrograms of testosterone (NA) or with oil vehicle only (control). Both groups were sacrificed at 8 weeks of age. Compared to controls, NA rats showed significantly higher plasma PRL levels (7.3 fold), anterior pituitary (AP) PRL content (2.1 fold) and plasma estradiol levels (2.1 fold). AP VIP content was extremely higher (61 fold) in NA rats than in controls. However, NA did not affect VIP content in the suprachiasmatic nucleus, paraventricular nucleus or median eminence. These results suggest that the NA-induced hyperprolactinemia may be mediated, at least in part, by paracrine and/or autocrine effects of the increased AP VIP on PRL secretion. However, since the potentiation by NA of the AP VIP content was extremely marked compared to those of the other parameters, the possibility was also raised that the increased AP VIP may be involved in other endocrine and/or nonendocrine events occurring in the AP.     

Severe intestinal involvement in Wegener''s granulomatosis

A case of Wegener's granulomatosis is described, in which the presentation was blood stained mucus diarrhoea. Severe ileal, caecal, and rectal involvement improved rapidly after treatment with cyclophosphamide, azathioprine, and prednisolone. Although intestinal disease is an uncommon feature of Wegener's granulomatosis, both in our own experience (four of 45 cases) and in the literature, this diagnosis should be considered in view of the response to appropriate therapy.     

Hyaluronan-binding receptors: possible involvement in osteoarthritis

Our objectives were to compare the expression of the hyaluronan receptors CD44 and RHAMM in knee synovial tissue of patients with and without advanced osteoarthritis (OA). Both receptors were detected immunohistochemically; the staining appeared more intense in the tissues from the patients with advanced OA. Expression of CD44 and RHAMM were each significantly increased (p < 0.05) in synovial tissue from patients with OA, as determined by means of Western-blot analysis. The findings suggested that changes in levels of the HA-binding proteins might be implicated in the development or progression of OA.     

Hyaluronan-binding receptors: possible involvement in osteoarthritis

Abstract

Our objectives were to compare the expression of the hyaluronan receptors CD44 and RHAMM in knee synovial tissue of patients with and without advanced osteoarthritis (OA). Both receptors were detected immunohistochemically; the staining appeared more intense in the tissues from the patients with advanced OA. Expression of CD44 and RHAMM were each significantly increased (p < 0.05) in synovial tissue from patients with OA, as determined by means of Western-blot analysis. The findings suggested that changes in levels of the HA-binding proteins might be implicated in the development or progression of OA.     

Risk for cardiac involvement in essential hypertension

The evidence is inescapable that even mild essential hypertension is associated with left ventricular hypertrophy, regardless of the age of the patient. Increased left ventricular afterload must play a major role in the pathogenesis of the hypertrophy; however, further proof of this awaits our improved understanding of the quantitation of afterload in the clinical setting. Other factors, including the adrenergic nervous system and blood viscosity, may play an additional role, possibly mediated through alterations in afterload or by direct myocardial action. Left ventricular hypertrophy exerts a positive benefit by normalizing wall stress in patients with hypertension. Especially in patients without coexistent coronary abnormalities, systolic function is normal and abnormalities of diastolic function are of uncertain clinical importance. Because echocardiography now provides a convenient and sensitive noninvasive means of following patients with left ventricular hypertrophy, long-term studies are now needed to document the incremental risk (or benefit) of left ventricular hypertrophy over blood pressure itself in the eventual morbidity of essential hypertension. The recognition of left ventricular hypertrophy in a patient with borderline elevation of blood pressure poses a new clinical dilemma. Should treatment be instituted based on this additional finding? In view of the data correlating stress, exercise, and mean daily blood pressure with left ventricular hypertrophy and the reduction of left ventricular mass following lowering of blood pressure, it has been our practice to treat patients with left ventricular hypertrophy more readily than those without left ventricular hypertrophy. The rationale in this approach is not that left ventricular hypertrophy per se is harmful, but rather that it indicates a greater degree of afterload than may be evident from office blood pressure measurements.     

Non-invasive signs of cardiac involvement in essential hypertension

The relationship between various non-invasive signs of hypertensivecardiac involvement and blood pressure (BP) was studied in 120middle-aged men recruited from a BP-screening of a random populationsample. The men, representing a wide range of BP, were dividedinto four BP groups (normotensive, and borderline, mild andmoderate-severe hypertension), and were investigated by conventionalelectrocardiography (ECG), chest X-ray, echocardiography, apexcardiography/phonocardiographyand corrected orthogonal ECG. In the hypertensive groups a lower proportion of subjects withsigns of cardiac involvement were identified by conventionalECG and chest X-ray than by the other methods. A significantassociation between the prevalence of pathological findingsand level of blood pressure (P < 0.05–0.01) was foundfor conventional and corrected orthogonal ECG and apexcardiography/phonocardiography.With echocardiography, concomitant increased thickness (>12 mm) of both the interventricular septum and left ventricularposterior wall, but not of one structure alone, was significantlyassociated with BP (P < 0.05). In borderline subjects, pathological findings were surprisinglycommon. However, many of these subjects had single abnormalities,whereas those with higher BP had an increasing degree of multiplepathological findings. We conclude that in many hypertensives there are signs of cardiacinvolvement that can be revealed by means of sensitive non-invasivemethods. Single signs can be revealed in mild hypertension butthe number and severity of the different abnormalities increases(dramatically) with increasing BP. It is probable that thesevarious types of cardiac involvement carry prognostic informationthat could help in treatment decisions.     

Ammonia production by intestinal bacteria

Bacterial growth and the production of ammonia from urea and by deamination of peptone has been examined at various pHs in both conventional static bacterial cultures and in a continuous cultivation system.Growth occurred on primary testing of 93 out of 100 strains of aerobic Gram-negative bacteria at pH 5, and 48 out of 50 strains of Esch. coli at pH 4.6.Hydrolysis of urea by Proteus mirabilis decreased steadily from pH 7.2 to pH 5.3; below pH 5.3 little hydrolysis occurred. Ammonia production from peptones by Esch. coli decreased from pH 7.2 to pH 4.6. Considerable variation was noted in the ability of different strains to produce ammonia. Experiments with cultures containing both Esch. coli and Pr. mirabilis showed that more ammonia was produced at low pH than was produced by cultures of single organisms.At low pH reduction in the count of organisms was not found to be an essential prerequisite for reduction of ammonia formation.     

How intestinal bacteria cause disease

An improved understanding of how intestinal bacteria cause disease has become increasingly important because of the emergence of new enteric pathogens, increasing threats of drug resistance, and a growing awareness of their importance in malnutrition and diarrhea. Reviewed here are the varied ways that intestinal bacteria cause disease, which provide fundamental lessons about microbial pathogenesis as well as cell signaling. Following colonization, enteric pathogens may adhere to or invade the epithelium or may produce secretory exotoxins or cytotoxins. In addition, by direct or indirect effects, they may trigger secondary mediator release of cytokines that attract inflammatory cells, which release further products, such as prostaglandins or platelet-activating factor, which can also trigger secretion. An improved understanding of pathogenesis not only opens new approaches to treatment and control but may also suggest improved simple means of diagnosis and even vaccine development.