Estimation of foetal brain dose from I-131 in the foetal thyroid

The ingestion of I-131 by pregnant women can have consequences for the developing foetus, in particular brain function. As the foetal thyroid accumulates iodine from the twelfth week of gestation onwards, the determination of foetal brain dose resulting from such I-131 accumulation is essential. Normal dosimetric methods fail to treat the case of foetus. Using an approximation method based on the MIRD approach, a foetal dose estimation scheme is developed to allow the determination of foetal brain dose from foetal thyroid irradiation. Dose values are obtained for the foetus based on the maternal intake of I-131. It was found that the choice of biokinetic model for the mother/foetus has a large impact on the determined dose estimate.     

Double coupling Edman chemistry for high-sensitivity automated protein sequencing

Capillary electrophoresis with laser-induced fluorescence detection (CE-LIF) is a promising new method for the analysis of protein sequencing products. It gives 10 zmol (1 zmol = 10(-21) mol) limits of detection (3 sigma) for fluorescein thiohydantoin (FTH) amino acids. We have developed a separation for the (FTH)-amino acid products generated from 18 of the 20 coded amino acids. The extremely low volume requirement associated with CE-LIF makes it incompatible with commercial sequencers. For this reason, we have also been developing a miniaturized sequencer that can be more easily coupled to our detection system. Both the CE-LIF system and the miniaturized sequencer are described.     

Factors related to rehospitalization within thirty days of discharge after coronary artery bypass grafting

BACKGROUND: Early rehospitalization after coronary artery bypass grafting (CABG) is an expensive and frequently adverse outcome. Rehospitalization rates after various surgical procedures have been used as an indicator of quality of care. Determining the extent to which rehospitalization rates reflect patient case mix and severity of illness rather than quality of care requires detailed information regarding the patients, the care they received, and the reasons for their rehospitalization. METHODS: We conducted a nested case control study comparing 110 CABG patients who were rehospitalized within 30 days after discharge with 224 control patients. Control patients were randomly selected from patients undergoing CABG during the same time frame as the cases and were matched on age, gender, and priority of surgery. A detailed chart review provided information regarding treatment in the postsurgical period, in addition to the preoperative information collected on all CABG patients as part of an ongoing regional prospective study. RESULTS: The overall rehospitalization rate was 13.8%. The most common reasons for rehospitalization included: wound infection (19%), atrial fibrillation (13%), pleural effusion (11%), and thromboembolic event (10%). Preoperative severity of illness and comorbidity accounted for 24% of the total variance. After adjustment for these factors, discharge hematocrit less than 30% (OR = 2.01, p = 0.018) and several discharge medications including: antiarrhythmics (OR = 3.26, p = 0.047), diuretics (OR = 2.18, p = 0.055), beta blockers (OR = 0.44, p = 0.036), and long length of stay (more than 7 days; OR = 2.09, p = 0.029) were the most important predictors of rehospitalization risk. CONCLUSIONS: Although the reasons for rehospitalization after CABG are heterogeneous and related to patient severity of illness as well as comorbid status, several of the most common are potentially preventable and related to quality of care. Rehospitalization was not related to early discharge.     

Approach to the patient with pulmonary disease

The approach to the HIV-infected patient with pulmonary disease is summarized by the algorithms in Figures 3 and 4. These are not intended to be followed in a rigid step-wise fashion. Rather, the practitioner's knowledge of the patient with his or her accompanying medical risks influences the path taken, including the depth and the speed of the evaluation. For example, the patient with cough who is afebrile and breathing at 18 breaths a minute, with a normal chest radiograph and a CD4 count of 350 cells/mm3, is reasonably treated with a macrolide or cephalosporin for bacterial bronchitis and clinical follow-up while awaiting cultures (see Fig. 4). A febrile patient with a cough productive of thin mucus, but known to have a CD4 count of 60 cells/mm3 should be started on anti-PCP therapy while being evaluated for PCP with an induced sputum and if nondiagnostic, a bronchoscope despite a normal chest radiograph. Screening can be as simple as placing an oximeter on the patient's finger in the clinic. If the oxygen saturation of a patient with a normal chest radiograph is low, then the patient should be hospitalized and begun on treatment for PCP while diagnostic evaluation is initiated. If the oxygen saturation is normal, the patient can be exercised to elicit desaturation. If there is no desaturation, PCP is unlikely. If the results are equivocal (i.e., a decrease in saturation, but less than 3%), rest and exercise arterial blood gases can be performed, along with a Dlco-Gallium scanning can be done in patients known to have abnormal Dlco or those who cannot exercise. Patients with focal infiltrates who have acute onset of symptoms (see Fig. 4) commonly have bacterial infections, but the possibility of PCP or TB should not be dismissed. Induced sputum should be examined if TB or PCP is suspected. Patients who are severely ill might go quickly to bronchoscopy without awaiting improvement on empiric therapy. The patient with diffuse infiltrates (see Fig. 4) needs no screening because the presence of disease is apparent from the radiograph. The diagnostic part quickly leads to bronchoscopy for these patients and the initiation of therapy for PCP when suspected. In patients with known pulmonary KS, gallium scanning can be helpful to rule out acute infection, but bronchoscopy is warranted if the patient is severely ill, or at high risk for PCP. This approach should avoid unnecessary procedures in patients with simple bacterial infections, without missing opportunistic infections and tumors.     

Performance characteristics of a whole-body PET scanner

METHODS: This study characterizes the performance of a newly developed whole-body PET scanner (Advance, General Electric Medical Systems, Milwaukee, WI). The scanner consists of 12,096 bismuth germinate crystals (4.0 mm transaxial by 8.1 mm axial by 30 mm radial) in 18 rings, giving 35 two-dimensional image planes through an axial field of view of 15.2 cm. The rings are separated by retractable tungsten septa. Intrinsic spatial resolution, scatter fraction, sensitivity, high count rate performance and image quality are evaluated. RESULTS: Transaxial resolution (in FWHM) is 3.8 mm at the center and increases to 5.0 mm tangential and 7.3 mm radial at R = 20 cm. Average axial resolution decreases from 4.0 mm FWHM at the center to 6.6 mm at R = 20 cm. Scatter fraction is 9.4% and 10.2% for direct and cross slices, respectively. With septa out, the average scatter fraction is 34%. Total system sensitivity for true events (in kcps/(microCi/cc)) is 223 with septa in and 1200 with septa out. Dead-time losses of 50% correspond to a radioactivity concentration of 4.9 (0.81) microCi/cc and a true event count rate of 489 (480) kcps with septa in (out). Noise-equivalent count rate (NECR) for the system as a whole shows a maximum of 261 (159) kcps at a radioactivity concentration of 4.1 (0.65) microCi/cc with septa in (out). NECR is insensitive to changes in lower gamma-energy discrimination between 250-350 keV. CONCLUSIONS: The results show the performance of the newly designed PET scanner to be well suited for clinical and research applications.     

Conformal proton therapy for prostate carcinoma

The suppression of apoptosis may contribute to the carcinogenicity of the peroxisome proliferators (PPs), a class of non-genotoxic rodent hepatocarcinogens. Our previous work demonstrated that the PP nafenopin suppressed both spontaneous and transforming growth factor beta1 (TGFbeta1)-induced hepatocyte apoptosis both in vivo and in vitro. Here, we extend these observations by demonstrating the ability of nafenopin to suppress apoptosis induced by other major candidates for the signalling of cell death in the liver. Treatment of rat or mouse hepatocyte monolayers with TGFbeta1 or the DNA damaging drugs etoposide or hydroxyurea induced high levels of apoptosis. Western blot analysis did not support a role for either p53 or p21waf1 in etoposide-induced apoptosis in rat hepatocytes. Treatment of mouse hepatocytes with an agonistic anti-Fas antibody also resulted in an induction of high levels of apoptosis. Pre-addition and continued exposure to nafenopin suppressed apoptosis induced by all three stimuli. Overall, our studies demonstrate that the ability of nafenopin to protect hepatocytes from apoptosis is not restricted to species or apoptotic stimulus. It is possible, therefore, that the PPs may suppress apoptosis by acting on diverse signalling pathways. However, it seems more likely that nafenopin suppresses hepatocyte apoptosis elicited by each death stimulus by impinging on a core apoptotic mechanism.     

Injections of D-amphetamine into the ventral pallidum increase locomotor activity and responding for conditioned reward: a comparison with injections into the nucleus accumbens

The nucleus accumbens and ventral pallidum receive dopamine (DA) projections from the mesencephalon. Although DA inputs to the nucleus accumbens are implicated in both locomotion and reward processes, little is known of the behavioural significance of DA in the ventral pallidum. These studies examined the effects of D-amphetamine injected into the nucleus accumbens or ventral pallidum on locomotor activity and responding for a conditioned reward (CR). In the nucleus accumbens D-amphetamine dose dependently (1, 3 and 10 microg) increased locomotion within 5-10 min of injection. Intra-ventral pallidum microinjections of D-amphetamine also increased activity in this dose range, but the effect occurred with a longer latency (5-20 min). The magnitude of the response evoked by ventral pallidum injections was lower than that evoked by nucleus accumbens injections. The GABAA antagonist picrotoxin (0.1 microg) stimulated activity when injected into the ventral pallidum but not the nucleus accumbens, providing a pharmacological dissociation between the two injection sites. In the CR studies, D-amphetamine injected into both sites potentiated responding for a CR previously paired with food delivery, without altering responding on an inactive lever. Picrotoxin injected into the ventral pallidum reduced responding and abolished the selectivity of responding for CR. The results show that DA release in the ventral pallidum enhances locomotion and responding for a CR, providing evidence that DA in the ventral pallidum plays a significant role in the mediation of the effects of D-amphetamine. The failure of picrotoxin to elevate responding for CR despite increasing locomotor activity indicates that pharmacologically-induced blockade of GABAA receptors in the ventral pallidum disrupts goal-directed responding.     

Molecular interaction between the Fyn-associated protein SKAP55 and the SLP-76-associated phosphoprotein SLAP-130

It has previously been reported that in resting T-lymphocytes the protein tyrosine kinase p59 constitutively co-precipitates with four phosphoproteins of 43, 55, 85, and 120 kDa, respectively. We have recently cloned the 55-kDa protein that was termed Src kinase-associated phosphoprotein of 55 kDa (SKAP55). Here we demonstrate that the recently characterized SH2-domain-containing leukocyte protein 76-associated phosphoprotein of 130 kDa (SLAP-130) is one of the components of the Fyn complex and that it also co-precipitates with SKAP55 in human T-cells. We establish that SKAP55 and SLAP-130 associate with each other when both molecules are co-expressed in COS cells. By co-transfection of truncated mutants of SKAP55 and SLAP-130 as well as by using the two-hybrid selection system, we further demonstrate that the association between SLAP-130 and SKAP55 is direct and involves the Src homology 3 domain of SKAP55 and the proline-rich sequence of SLAP-130.     

Pre-incision infiltration with lidocaine reduces pain and opioid consumption after reduction mammoplasty

BACKGROUND: The main purpose of the reconstruction of the cranium is the protection of the brain. Besides we have to consider important functional and aesthetic necessities in order to achieve satisfactory results. METHODS: Thirty-six clinical cases, operated from November 1991 to June 1996, in which the reconstruction of the cranial vault is carried out by a polymethylmethacrylate acrylic resin are analysed. The causes and locations of the most common bone defects and the main indications for reconstruction are examined. While the repair of the osseous gaps caused by neoplasms is immediate, in the traumatic occurrences, in order to reduce the probability of infectious complications, an average time of 11 months elapsed from the first operation. The surgical technique, with slightest alterations, is the same in all the presented cases, preparing the acrylic resin straight on the operating table. The resin, moulded and adapted to the defect until its complete hardening, presents, thanks to its properties, manifold advantages (and few real disadvantages). RESULTS: The results, in terms of complications, are very satisfactory, with an infectious rate of 2.7%. Besides, in one third of the patients, a considerable clinical improvement after the repair has been observed. CONCLUSIONS: According to personal experience, it is possible to affirm that polymethylmethacrylate, with its remarkable plasticity and stability in time, can always guarantee a satisfactory functional and aesthetic result.