Detection and analysis of

No abstract

Xeroderma pigmentosum is an unusual neurocutaneous disorder. Recent studies have classified patients with xeroderma pigmentosum into 10 groups by somatic cell hybridization methods. In this report we describe 32 patients with Group A xeroderma pigmentosum, including 1 patient with an atypical case, who were assessed for neurological complications. Of these patients, 17 had microcephaly, 13 short stature, and 21 mental retardation. In patients over 7 years of age, sensorineural deafness and spinocerebellar signs such as nystagmus, dysarthria, tremor, and ataxia were frequently observed; no patients below 7 years of age had such neurological complications. Electroencephalographic studies revealed abnormal slow and low voltage background activity. Two patients had focal abnormal discharges, one of whom developed versive seizures. Cranial computed tomographic scans revealed abnormalities, including ventricular dilatation, cerebral atrophy, cerebellar and brainstem atrophy, and cranial bone thickening. A patient with an atypical case of Group A xeroderma pigmentosum had less skin and neurological involvement, and higher levels of postultraviolet colony-forming ability and host cell reactivation than did a typical Group A case. It is possible that these less severe cytological findings are responsible for the less severe skin lesions and neurological complications noted clinically.

Congestive heart failure is associated with extracellular matrix (ECM) remodeling resulting from an imbalance in the synthesis and degradation of ECM collagen.1,2) Severe degrees of cardiac remodeling are associated with an increased risk of heart failure, morbidity, and mortality in patients with heart failure. 3,4) Neurohumoral activation plays a key role in compensatory mechanisms and myocardial remodeling in patients with heart disease, and is accompanied by the expression of matrix metalloproteinases (MMPs). 2,3,5,6) The MMPs compose a family of enzymes that contribute to ECM remodeling in several disease states, by promoting ECM degradation. Interestingly, several studies have shown that increased MMP expression and activation are involved in myocardial remodeling processes associated with several heart diseases. 4,[7][8][9] In addition, animal models of heart disease showed increases in MMP activity and left ventricular (LV) remodeling. [10][11][12] Likewise, MMP inhibition and deletion are reported to prevent LV remodeling and dysfunction, suggesting the potential usefulness of MMP inhibitors (MMPi) in patients with heart failure. Spontaneously hypertensive rats showed increased collagen accumulation and MMP activation, which were reversed after treatment with an MMPi. 6) MMP knockout mice showed preserved cardiac function and decreased myocardial fibrosis in myocardial infarction. 13,14) Furthermore, the MMPi doxycycline was reported to prevent cardiac hypertrophy, MMP activity, and myocardial fibrosis in rats with myocardial ischemia. 15) However, few studies have examined the effects of doxycycline on b-agonist-induced myocardial fibrosis. Therefore, we investigated the effects of doxycycline on isoproterenol-induced myocardial fibrosis and MMP expression. MATERIALS AND METHODSFour-week-old Wistar-Kyoto rats (nϭ42) were obtained from a commercial laboratory (Charles River, Yokohama, Japan). The rats were housed individually in an air-conditioned room with a 12-h dark-light cycle and were given a standard diet with ad libitum access to tap water. The rats were divided into 3 groups: control (CTL), isoproterenol (ISO), and isoproterenol with doxycycline (ISOϩDOX). This study was approved by the Institutional Laboratory Animal Care and Use Committee of the School of Veterinary Medicine of Kitasato University, Japan.Study 1 Four-week-old rats (nϭ18; body weight, 90-110 g) were divided into 3 groups: control (nϭ6), ISO (nϭ 6), and ISOϩDOX (nϭ6). Animals were anesthetized with an intraperitoneal injection of pentobarbital (50 mg/kg). A 3Fr catheter was implanted into the jugular vein and the drug was administered with an infusion pump (Nihon Kohden, Tokyo, Japan). The rats were stabilized for 15 min and placed in the prone position above an ultrasound standoff pad (3M Health Care Ltd., Tokyo). Control rats were infused 0.9% saline alone. L-Isoproterenol (Sigma-Aldrich Co., St. Louis, MO, U.S.A.) was infused at 0.5 and 1.0 mg/kg/min for 5 min. In ISOϩDOX rats, doxycycline hydrochloride was infused at 17-18 m...

The correlation between the severity of vibration syndrome and hand-tool operating time in chain saw workers has been studied. The total chain saw operating time was calculated by using the equation: chain saw operating hours/day x days/year x years, and 266 chain saw operators were classified into four groups (0-2000 h, 2000-5000 h, 5000-8000 h, over 8000 h). Forty-six forestry workers not using chain saws were used as controls. The prevalence rates of symptoms were checked and statistically compared in each group.In the group with under 2000 hours' experience, symptoms were generally confined to tingling, numbness, or pain; with 2000-5000 hours peripheral nerve and circulatory disturbances, including Raynaud's phenomenon, and muscle and general body conditions were influenced to some degree; with 5000-8000 hours' functional changes were noted; while with over 8000 hours about half the operators suffered severely from functional or organic changes due to vibration.Since Lorigal first reported the occurrence of occupational hazards due to the use of vibrating tools, many cases of workers affected by the use of vibrating tools in a wide range of industrial tasks (riveting, drilling, or jobs requiring chain saws and pneumatic hammers) have been reported. Many researchers first paid attention to vibration-induced white finger (Raynaud's phenomenon) and this syndrome is now well described. Recently, however, the concept of a "vibration syndrome" has been introduced to encompass the complex of symptoms associated with vibrating tools, such as vibration-induced white finger (Raynaud's phenomenon), hypesthesia of the hand and arm, weakness of grip strength, restriction of joints in hands, and so on.2-4 Several papers investigating the frequency and severity of vibration syndrome have been published,57 and criteria for the diagnosis of vibration syndrome have been established and used to describe the progress of this syndrome.6 These papers have detailed the progress of the syndrome but they do not show the correlation between the time for which vibrating tools have been used and each symptom, except Raynaud's phenomenon.In this paper we have introduced "total operating time (TOT)' as a new index of vibration dose and have tried to show the correlation between the sev-92 erity of vibration syndrome and total hand tool operating time by using the medical records of over 2000 chain saw workers. The field study was carried out from 1975 to 1979. SubjectsOver 2000 forestry workers in the mountain area near Osaka in Japan were surveyed and examined for vibration syndrome. From these, 266 subjects professionally exposed to chain saw hand-arm vibration were selected; 46 controls, forestry workers never exposed to vibration, were also selected. We used these subjects who were all men and aged from 40 to 59 to eliminate the effects of sex and age.To determine the vibration exposure dose for an individual, TOT was calculated from the full occupational history using the following equation: chain saw operating hours/day x days/year ...