1H and 13C NMR spectra of poly(propyl α-bromoacrylate) and poly(methyl α-bromoacrylate)

The ¹³C NMR spectra measured at 25 MHz of the methyl and propyl esters of isotactic and syndiotactic poly(α-bromoacrylate) were sufficiently resolved to be analysed for pentad tacticity sequences. The pentad tacticity of the syndiotactic polymers prepared with free radical initiators at ?40°C agreed with those calculated for Bernoullian sequence distributions based on P_r values of 0,83–0,87. The tacticities of the isotactic polymers prepared with heterogeneous catalysts were determined on the basis of these assignments. Good internal consistency was obtained between the calculated and observed pentad proportions from the quaternary and carbonyl carbon peaks in the spectra of these polymers. The order of chemical shifts for the meso and racemic dyads and tetrads in these polymers were opposite to those found in the equivalent methacrylate polymers, but as with the latter, the ¹³C-T₁ values were longer in the isotactic than in the syndiotactic polymers.     

Release of platelet-activating factor from rabbit heart perfused in vitro by sera with transplantation alloantibodies

During "hyperacute rejection" of rabbit heart perfused with transplantation alloantibodies, platelet activating factor (PAF) was released into the coronary effluent, which appeared to have physicochemical and functional properties similar to the 1-octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine (synthetic PAF) and to PAF obtained from IgE-sensitized rabbit basophils. The release of PAF was associated with an early tachycardia, followed by increasing bradycardia and conduction arrhythmias, as well as decrease of coronary flow and of amplitude of electrogram. The heart stopped beating within 30 min. The release of PAF as well as the "rejection" required the presence of fresh rabbit serum as a source of complement. The PAF receptor antagonist SRI 63-072 in a dose of 0.6 mg, reversed by 70% the reduction of coronary flow within 2-4 min after its addition to the perfusate; ED50 was 0.4 mg. Bradycardia and arrhythmia were reduced; however, the normal electrical activity was only occasionally restored. The cessation of heart action was delayed up to 50 min after the beginning of perfusion with transplantation alloantibodies and complement, but it was not prevented. These results suggest that PAF is released during "rejection" of the heart perfused in vitro with serum containing transplantation alloantibodies in the absence of inflammatory cells and that this mediator is at least in part responsible for the deterioration of cardiac function.     

Respiratory disability in ex-cotton workers.

A high proportion of textile workers handling cotton and flax complain of respiratory symptoms and show a loss in lung function. These effects are reversible in the early stages but the degree to which they lead to permanent respiratory disability is unknown. Two surveys were therefore conducted in which respiratory function and symptoms were compared in ex-textile workers and in control subjects who had never been exposed to textile dusts. One survey was of ex-flax workers in Northern Ireland. The present survey was of ex-cotton workers in Lancashire. A survey of random population samples in Oldham and Bolton, in both of which cotton had formerly been the most important source of employment, was conducted. After allowing for age, height, and smoking, lung function was about 2-8% lower in the ex-textile workers than in controls who had never been exposed to any dust. Ex-textile workers were slightly shorter than the controls, suggestive of past social and nutritional deprivation which may have contributed to the decrement in lung function. There was evidence of a small but increasing decrement in lung function with an increase in a "dust exposure" score. For men, about 15 years of heavy dust exposure was associated with a loss in FEV1 equivalent to that shown by light or ex-smokers. For women, 15 years of heavy dust exposure appeared to be associated with a decrement in FEV1 about half that of light smoking.     

Respiratory disability in ex-cotton workers

A high proportion of textile workers handling cotton and flax complain of respiratory symptoms and show a loss in lung function. These effects are reversible in the early stages but the degree to which they lead to permanent respiratory disability is unknown. Two surveys were therefore conducted in which respiratory function and symptoms were compared in ex-textile workers and in control subjects who had never been exposed to textile dusts. One survey was of ex-flax workers in Northern Ireland. The present survey was of ex-cotton workers in Lancashire. A survey of random population samples in Oldham and Bolton, in both of which cotton had formerly been the most important source of employment, was conducted. After allowing for age, height, and smoking, lung function was about 2-8% lower in the ex-textile workers than in controls who had never been exposed to any dust. Ex-textile workers were slightly shorter than the controls, suggestive of past social and nutritional deprivation which may have contributed to the decrement in lung function. There was evidence of a small but increasing decrement in lung function with an increase in a "dust exposure" score. For men, about 15 years of heavy dust exposure was associated with a loss in FEV1 equivalent to that shown by light or ex-smokers. For women, 15 years of heavy dust exposure appeared to be associated with a decrement in FEV1 about half that of light smoking.     

Susceptibility and resistance to environmental carcinogens in the development of carcinoma of the lung

Eight selected cases are presented to show different effects of the environment on the lung. Some appear to lack resistance to environmental carcinogens. The variations in response and an assessment of the carcinogens involved are discussed. Further study of these poorly understood etiologic factors is needed.     

Needle biopsy of renal allografts: comparison of two techniques

Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.     

A comparison of residential heroin detoxification patients and methadone maintenance patients

Interviews were conducted with 101 heroin dependent persons entering a residential drug-free detoxification unit in 1989. These self-report data were compared with those previously collected in 1985-6 from 457 methadone maintenance patients. The detoxification patients injected less frequently, used less heroin, had been physically dependent for a shorter period and were more likely to be single, unemployed and to have been charged with a criminal offence in the last 12 months. It is suggested that these findings may indicate that addicts who use more heroin are less likely to seek drug-free detoxification. The wider implication of the finding is that future surveys of injecting drug users should assume that there are significant differences between heroin users entering different modalities of treatment.     

Concurrent carboplatin and iodine-125 brachytherapy for recurrent glioblastoma multiforme

Toxicity and safety study of concurrent carboplatin chemotherapy and iodine-125 (I-125) brachytherapy. I-125 brachy therapy has an established albeit limited role in surgically accessible recurrent gliomas. Carboplatin has anti-tumoral; activity against gliomas and demonstrated sensitization of tumor to radiotherapy. In 15 patients (age range 30-77 years; median 53) with recurrent glioblastoma multiforme, stereotactically placed catheters were afterloaded with I-125 sources. A median 50 Gy minimum treatment volume dose was delivered during a 100 h period in conjunction with continuous infusion carboplatin (100 mg/m(2)/20 h x 5). Tumor volumes ranged from 13 to 63 cm(3) (median, 32 cm(3)). Early complications included: headache (n=7), transient exacerbations of pre existing neurologic deficits (n=5), seizures (n=2), nausea/vomiting (n=2), myelosuppression (n=2) and a catheter site wound CSF leak (n=1). Late complications included: steroid dependency (n=10), carcinomatous meningitis in association with hydrocephalus (n=1) and radiation-induced necrosis requiring reoperation (n=6). All patients were evaluable with a median survival of 10 months. In 12 patients, best clinical and neuroradiographic response was stable disease all of whom died of recurrent tumor (local recurrence in 11; CSF dissemination in 1). In 3 patients best response was either complete (n=2) or partial (n=1) all of whom are alive with a median follow-up of 31 months. I-125 brachytherapy with concurrent carboplatin chemotherapy is associated with an acceptable level of toxicity, has anti-tumoral activity and warrants further investigation in carefully selected patients with recurrent gliomas.