MRI of muscular hamartoma of the breast

Muscular hamartoma is a well‐demarcated tumour composed of smooth muscle and adipose tissue. We report the MRI findings of a patient with benign breast neoplasm. To the best of our knowledge, its appearance has not been previously reported.     

DNA mutilation of the pepsin 1 gene during rat glandular stomach carcinogensis induced by N-methyl-N'-nitro-N-nitrosoguanidine or catechol

The methylation patterns of the rat pepsinogen 1 (Pg1) genein preneoplastic and neoplastic stomach lesions induced by genotoxicN-methyl-N'-nitro-N-nitrosoguanidine (MNNG) or the non-genotoxiccarcinogen catechol were investigated. Male WKY/Ncrj rats weregiven MNNG in their drinking water (50 mg/l) for 30 weeks or0.8% catechol throughout the experiment (60 weeks). MNNG inducedPg1 altered pyloric glands (PAPG), adenomatous hyperplasiasand well-differentiated adenocarcinomas. Catechol also inducedPAPG and adenomatous hyperplasias although cancers did not develop.Adenomatous hyperplasias and adenocarcinomas all consideredof gastric type cells resembling surface mucous cells or pyloricgland cells with little or no Pg1 expression. In MNNG-inducedstomach cancers generally lacking Pg1, altered Pg1 gene methylationwas observed with both CCGG and GCGC sites being methylatedmore than normal pyloric mucosa. MNNG or catechol-induced adenomatoushyperplasias also demonstrated essentially the same methylationchanges in the CCGG, but not in the GCGC sites. In the mucosacontaining PAPG in groups treated with MNNG or catechol themethylation patterns of the Pg1 gene were quite similar to thoseof normal pyloric mucosa, although the CCGG sites tended todemonstrate slightly increased methylation. The results suggestthat the altered methylation of the Pg1 gene observed in stomachcancers is acquired early in the carcinogenic process and progressivemethylation changes occur with tumor development.     

Clinical manifestations and inflammatory cytokine responses in patients with severe acute respiratory syndrome.

BACKGROUND AND PURPOSE: Severe acute respiratory syndrome (SARS) is a highly transmissible disease with significant morbidity and mortality. Death from SARS is most often due to rapidly progressive respiratory compromise (acute respiratory distress syndrome, ARDS) and subsequent multi-organ dysfunction. However, the mechanisms evoking respiratory distress and a fulminant systemic response remain unclear. In order to elucidate the pathogenic mechanisms of SARS, we analyzed clinical manifestations and levels of serum cytokines of SARS patients. METHODS: Fourteen hospitalized patients with a diagnosis of SARS-associated coronavirus infection at National Taiwan University Hospital from March to May 2003 were included. Data on clinical manifestations, parameters of laboratory tests, complications and final outcomes of patients were collected retrospectively. Serial plasma inflammatory cytokines, including interleukin (IL)-1beta (IL-1beta), IL-6, IL-8 and tumor necrosis factor-alpha (TNF-alpha) of preserved serum were measured by enzyme immunoassay. RESULTS: All 14 patients had fever, dry cough and dyspnea. Twelve were intubated during hospitalization. The median duration from onset of fever to the nadir level or most severe condition was 9 days for hypoxia, 7 days for lymphocytopenia, 6.5 days for thrombocytopenia, 9.5 days for maximal pulmonary infiltrates; to peak serum levels was 9 days for C-reactive protein (CRP), 10.5 days for IL-6, 13.5 days for IL-8 and 12 days for TNF-alpha; to defervescence was 13 days. There was no significant elevation of serum IL-1beta levels in any of the 14 patients. There were no significant differences in peak levels of IL-6, IL-8 and TNF-alpha between patients with and without ARDS. The 8 patients who died tended to have higher peak levels of serum TNF-alpha compared to those who survived (14 vs 9.1 pg/mL; p = 0.06). CONCLUSION: Rapid elevation of inflammatory cytokines-IL-6, IL-8 and TNF-alpha might play a role in the development of SARS-related ARDS. The timing of elevations in inflammatory cytokines and CRP is correlated with progression of pulmonary infiltrates of SARS patients. The peak level of serum TNF-alpha tends to be higher in patients who die of SARS than in those who survive. Our results indicate that CRP and TNF-alpha might be used as prognostic markers of SARS.     

Overview on SARS in Asia and the World

Severe Acute Respiratory Syndrome (SARS) is the first major novel infectious disease to hit the international community in the 21st century. It originated in southern China in November 2002, reached Hong Kong in February 2003 and spread rapidly thereafter to 29 countries/regions on five continents. At the end of the epidemic, the global cumulative total was 8098 with 774 deaths. Seven Asian countries/regions were among the top ten on the list. Mainland China and Hong Kong, SAR, accounted for 87% of all cases and 84% of all deaths. Severe acute respiratory syndrome is caused by a novel coronavirus. It has alarmed the world with its infectivity and significant morbidity and mortality, its lack of a rapid, reliable diagnostic test and lack of effective specific treatment and vaccination. The adverse impact on travel and business around the world, particularly in Asia, has been enormous. Some lessons learnt from this epidemic included: (1) any outbreak of infectious disease can rapidly spread around the world by air travel; (2) early reporting of the outbreak to neighbouring countries/regions and the World Health Organization is essential to prevent international spread; and (3) infection control, tracing and quarantine of contacts are essential to control the epidemic. Many questions remain unanswered, including the origin and pathogenesis of the novel coronavirus, the natural history and the best specific treatment of the disease. The SARS‐CoV has probably jumped from an animal host to humans. There is an urgent need to evaluate the human–animal habitat in southern China and to remove animal reservoirs if found.     

Differential controls of small and large motor unit activity in the masseter muscle with incisal stimulation in humans

The activity of masseter motor units with different spike amplitudes was recorded and reflex responses by force stimulation of an incisor were analyzed in humans. The effects of reflex responses varied depending on the level of prestimulus firing frequency (background activity, BGA). When small amplitude motor units and large amplitude motor units were tested at the same level of BGA, the former tended to exhibit excitatory reflexes and the latter inhibitory ones.     

Direct Inhibitory Effect of Chlorpromazine on Smooth Muscle of the Porcine Pulmonary Artery

Background: Chlorpromazine has been widely used by anesthesiologists to take advantage of its anesthesia-potentiating and vasorelaxing actions. However, the mechanisms of vasorelaxation induced by chlorpromazine are still not fully understood.

Methods: Using front-surface fluorometry of fura-2 and porcine pulmonary arterial strips, we investigated the effects of chlorpromazine on the intracellular Calcium2+ concentration ([Calcium2+]i) and force of vascular smooth muscle. The affinities of chlorpromazine and other neuroleptics to vascular alpha1 -adrenergic receptors were then determined by a radio-ligand binding study.

Results: Chlorpromazine (as much as 1 micro Meter) inhibited both the elevation of [Calcium2+]i and force in pulmonary arterial smooth muscle induced by 80 mM Potassium sup + -depolarization and 1 micro Meter norepinephrine in a concentration-dependent manner. The extent of inhibition by chlorpromazine in norepinephrine-induced contraction was much greater than that in 80 mM Potassium sup + -induced contraction. In contrast, as much as 1 micro Meter chlorpromazine had no effect on the increases in [Calcium2+]i or force induced by U46619, a thromboxane A2 analogue. Chlorpromazine also had no effect on the intracellular Calcium2+ release induced by U46619. In a radio-ligand displacement study, chlorpromazine, haloperidol, phentolamine, trifluoperazine, and imipramine inhibited the specific binding of [sup 3 Hydrogen] prazosin to the porcine aortic membranes, in this order of potency.     

Protective Effect of Zonisamide, an Antiepileptic Drug, Against Transient Focal Cerebral Ischemia with Middle Cerebral Artery Occlusion-Reperfusion in Rats

Summary: Purpose: The antiepileptic effects of zonisamide (ZNS) have been well documented experimentally and clinically. The purpose of this study was to examine whether ZNS reduces cerebral damage after transient focal ischemia in rats.
Methods : Ischemia was induced by a transient occlusion of the left middle cerebral artery (MCA) with a 3-0 nylon monofilament for 90 min. Neurological evaluation was performed by measuring the event of neurological deficit of the contralateral forepaw and hindpaw at 10 min and 1 day after MCA occlusion (MCAo). Brain infarct size was determined by measuring triphenyltetrazonium chloridenegative stained area of the serial brain sections 1 day after MCAo.
Results : The pre- or postischemic treatment with ZNS [(10–100 mgkg P.o.), 30 min before and 4 h after or 15 min and 4 h after the occlusion] markedly reduced cerebral damage in the ipsilateral hemisphere and the neurological deficit induced by transient ischemia. The reducing effect on the damage was observed in the cortical and subcortical regions. Preischemic treatment with carbamazepine (CBZ 60 mgkg p.0. twice 30 min before and 4 h after MCAo) tended to reduce the cerebral damage and neurological deficit, but the lower dose (20 mg/kg p.o. twice) did not. Valproate (VPA 1,000 mgkg p.o. twice) also had no effect.
Conclusions : ZNS at the anticonvulsant dose, unlike CBZ and VPA, ameliorated the brain infarction and the event of neurological deficit after transient focal cerebral ischemia. These data suggest that ZNS has therapeutic potential in protecting against ischemic cerebral damage, such as stroke.