Superior mesenteric artery aneurysm in systemic lupus erythematosus

We present a case of giant superior mesenteric artery (SMA) aneurysm in a patient with systemic lupus erythematosus (SLE). The ultrasound, computed tomography, magnetic resonance, and angiographic findings are discussed. To our knowledge, SLE associated with a giant SMA aneurysm as a late complication of previous lupus mesenteric arteritis has not been reported previously.

Age-associated alterations of the mitochondrial genome

Age-associated alterations of the mitochondrial genome occur in several different species; however, their physiological relevance remains unclear. The age-associated changes of mitochondrial DNA (mtDNA) include nucleotide point mutations and modifications, as well as deletions. In this review, we summarize the current literature on age-associated mtDNA mutations and deletions and comment on their abundance. A clear need exists for a more thorough evaluation of the total damage to the mitochondrial genome that accumulates in aged tissues.

The kidneys that nobody wanted: support for the utilization of expanded criteria donors

The continuing shortage of cadaveric donors necessitates constant reappraisal of donor refusal criteria. From 1/1/95 to 3/20/96, 180 renal transplants were performed at our center. Of these, 26 were kidney/pancreas, 30 pediatric, 37 live donor adult, and 87 adult cadaveric renal transplants (CRT). In the CRT group there were 31 recipients of kidneys that all other local transplant centers declined. We retrospectively compared this group of kidneys that nobody wanted (KNW) to the remaining 56 CRTs (controls) performed at our center during the same period. Of the 31 recipients of KNW, 18 received kidneys declined for reasons of advanced age, defined as > or =60 years (including 8 who also had a history of hypertension, 4 who also had >10% sclerosed glomeruli on biopsy, and 3 also declined based upon donor quality because of acute injury), 8 for donor quality alone (e.g., prolonged hypotension), 3 on the basis of biopsy results alone, and 2 for anatomic abnormalities. Twelve recipients of KNW were "dual transplanted" with both donor kidneys. Of 27 donor variables compared between the KNW and control groups, only donor age (52+/-17 versus 40+/-17 years, respectively) and lowest total 4-hr urine output (327+/-208 versus 507+/-437 cc, respectively) proved to be significantly different (p< or =0.05). Of the 25 recipient variables examined, a significant difference was found only in serum creatinine at one month posttransplant (2.6+/-1.8 versus 1.8+/-1.0 mg/dl, respectively), although there was no difference in serum creatinine at three and six months. Actuarial one year patient (100 vs. 95%) and graft (97 vs. 91%) survival, KNW vs. controls respectively, are excellent to date. Further analyses showed no differences in outcome variables between recipients of KNW versus controls when the donor age was > or =60 years. Similar outcome was achieved by transplanting both kidneys from a KNW donor into a single recipient as compared with single-kidney transplantation from control donors. Careful donor-recipient pairing using kidneys from advanced-age donors for smaller, advanced-age recipients provided good short-term outcome. In conclusion, there was no significant difference in short-term outcome in recipients of KNW versus controls despite differences in donor age and lowest total 4-hr urine output. We believe that, with careful consideration, existing donor selection criteria can be expanded to include certain donors previously considered unusable.

Inhibition of ecto-ATPase by PPADS, suramin and reactive blue in endothelial cells, C6 glioma cells and RAW 264.7 macrophages

1. Previous studies have shown that bovine pulmonary artery endothelium (CPAE) has P2Y and P2U purinoceptors, rat C6 glioma cells have P2U purinoceptors and mouse RAW 264.7 cells have pyrimidinoceptors, all of which are coupled to phosphoinositide-specific phospholipase C (PI-PLC). The dual actions of PPADS, suramin and reactive blue as antagonists of receptor subtypes and ecto-ATPase inhibitors were studied in these three cell types. 2. In CPAE, suramin, at 3-100 microM, competitively inhibited the PI responses induced by 2MeSATP and UTP, with pA2 values of 5.5 +/- 0.3 and 4.4 +/- 0.4, respectively. Reactive blue, at 1-3 microM, produced shifts to the right of the 2MeSATP and UTP curves, but no further right shift at 10 microM. PPADS, at 10 microM, caused a 3 fold right shift of the 2MeSATP curve, but no further shift at concentrations up to 100 microM. In contrast, a dose-dependent shift to the left of the UTP curve and a weak inhibition of the ATP response were seen with PPADS. 3. In RAW 264.7 cells, suramin and reactive blue, but not PPADS, competitively inhibited the UTP response, with pA2 values of 4.8 +/- 0.5 and 5.8 +/- 0.7, respectively. 4. In C6 glioma cells, although suramin and reactive blue inhibited the ATP response, a potentiation effect on ATP and UTP responses was seen with PPADS. 5. The ecto-ATPase inhibitory activity of these three receptor antagonists were determined. All three inhibited ecto-ATPase present in CPAE, C6 and RAW 264.7 cells, with IC50 values of 4, 4.8 and 4.7 for PPADS, 4, 4.4 and > > 4 for suramin, and 4.5, 4.7 and 4.7 for reactive blue. 6. This study indicates that PPADS, suramin and reactive blue ar ecto-ATPase inhibitors. This property, combined with their antagonistic selectivity for receptor subtypes, can result in inhibition of, potentiation of, or lack of effect on agonist-mediated PI responses. Reactive blue is a more potent antagonist than suramin on P2Y, P2U and pyrimidinoceptors, and PPADS is a weak antagonist for P2Y receptors.

Beta-amyloid induces apoptosis in human-derived neurotypic SH-SY5Y cells

Alzheimer's disease is primarily characterized by neurofibrillary tangles, senile plaques, and neurodegeneration. The major component of senile plaques is the beta-amyloid peptide (beta A4), which has been shown to be toxic to neurons in vitro. To date, the mechanism of beta A4-induced neurotoxicity has not been determined in human-derived neurons. In this report, we present evidence that programmed cell death, or apoptosis, is involved in the neurotoxic activity of beta A41-40 and beta A425-35 in the human-derived neurotypic cell line SH-SY5Y cells. The evidence for beta A4-induced apoptosis includes: (1) labeling of cell nuclei for DNA nicked ends; (2) morphological changes in ultrastructure that are consistent with apoptosis (shrunken cells with pyknotic nuclei); (3) DNA laddering which can be blocked by aurintricarboxylic acid (ATA), an inhibitor of apoptosis; and (4) marginal release of intracellular lactate dehydrogenase (LDH), an indicator of necrosis. These results suggest that apoptosis is the major event involved in beta A4-induced cytotoxicity in SH-SY5Y cells. A variety of reagents were tested to determine their activities against beta A4-induced DNA laddering. Nerve growth factor and free radical scavengers were inactive in this system. While ATA blocked DNA laddering resulting from either beta A4 or okadaic acid treatment, Congo red specifically attenuated only beta A4-induced DNA fragmentation. These results suggest that compounds which bind fibrillar beta-peptides can protect this human neurotypic cell line against apoptosis induced by beta A4.

Acute esophageal food impaction treated by water-soluble contrast esophagography with maneuvers

This report describes a case of acute esophageal food impaction in the lower esophagus treated by proper physical motions during esophagography using water-soluble contrast medium (WSCM). WSCM was used to avoid the complication from unexpected perforation during the examination. Relief of esophageal obstruction may be accomplished by asking the patient to jump up and down on the ground. Esophagography using WSCM combined with appropriate physical motions may be helpful in treating patients suffering from acute esophageal food impaction.

Expression in human endothelial cells of ADP-ribosylation factors, 20-kDa guanine nucleotide-binding proteins involved in the initiation of vesicular transport

ADP-ribosylation factors (ARFs) are approximately 20-kDa, guanine nucleotide-binding proteins, initially discovered as stimulators of cholera toxin ADP-ribosyltransferase activity and subsequently shown to participate in vesicular trafficking. Five of the six mammalian ARFs have been identified in human tissues by molecular cloning. They fall into three classes (class I: ARFs 1-3; class II: ARFs 4, 5; class III: ARF 6) based on deduced amino acid sequence, size, phylogenetic analysis, and gene structure. Similar to the rab family of approximately 20 kDa guanine nucleotide-binding proteins, the ARFs appear to function in specific trafficking pathways. The presence of a specific ARF might serve as a marker for that pathway. To verify expression of ARF mRNA and protein in human umbilical vein endothelial cells, immunoreactivity using antibodies specific for each ARF class, quantitative polymerase chain reaction (PCR) using ARF-specific, internal cRNA standards containing unique restriction enzyme cleavage sites introduced by point mutations, and Northern analysis with probes specific for ARFs 1, and 3-6, were utilized. PCR and Northern analysis were in agreement in showing that amounts of mRNA for ARF 1 and ARF 4 were similar and higher than those of ARF 3 and ARF 5 which were greater than ARF 6. Primarily, Class 1 ARF proteins were detected by immunoreactivity, with the majority in the supernatant fraction. The relative expression of ARFs in endothelial cells thus differs from that in neuronal tissues where it had been found that ARF3 is the predominant species.

Synthesis and structure-activity relationships of 2-pyridones: a novel series of potent DNA gyrase inhibitors as antibacterial agents

Two novel series of 2-pyridones were synthesized by transposition of the nitrogen of 4-quinolones to the bridgehead position. This subtle interchange of the nitrogen atom with a carbon atom yielded two novel heterocyclic nuclei, pyrido[1,2-alpha]pyrimidine and quinolizine, which had not previously been evaluated as antibacterial agents and were found to be potent inhibitors of DNA gyrase. Quinolizines with a methyl group at the 9-position such as (S)-45a (ABT-719) demonstrate exceptional broad spectrum antibacterial activity. Most notably, they are active against resistant bacteria such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant strains of enterococci, and ciprofloxacin-resistant organisms. In addition, 2-pyridones also possess favorable physiochemical and pharmacokinetic properties. These 2-pyridones were synthesized from the commercially available starting materials by 10-17 linear transformations. The structure of an adduct yielded by this sequence, (S)-45a (ABT-719), was determined by X-ray crystallographic analysis.

Characterization of signaling pathways of P2Y and P2U purinoceptors in bovine pulmonary artery endothelial cells

The actions of ATP on the endothelium are mediated by P2 purinoceptors. We have shown that P2Y and P2U purinoceptors coexist in bovine pulmonary artery endothelial cells (CPAE), where they induce phosphoinositide (PI) turnover and Ca2+ mobilization. The relative order of potency (based on the threshold concentration) of nucleotide analogues (1-100 microM) in stimulating the accumulation of inositol phosphate (IP) was 2-methylthio-ATP (2MeSATP) = 2-methylthio-ADP (2MeSADP) > or = 2ClATP > UTP = ATP = ADP. alpha, beta-methylene ATP, beta, gamma-methylene ATP, UDP, adenosine-5'-tetraphospho-5'-adenosine, and adenosine-5'-pentaphospho-5'-adenosine had no effect at concentrations as high as 100 microM. At maximal concentrations, the IP responses to 2MeSATP and UTP were additive, whereas those to ATP and either 2MeSATP or UTP were not. Moreover, the maximal response to 2MeSADP was additive to that to UTP but not to that of 2MeSATP. Pretreatment with pertussis toxin slightly inhibited 2MeSATP- and UTP-stimulated IP generation by 15%. Under Ca(2+)-free conditions, UTP-induced IP formation was inhibited more markedly than that induced by 2MeSATP. Short-term treatment of the cells with phorbol 12-myristate-13-acetate (PMA) resulted in a dose-dependent inhibition of 2MeSATP-induced IP formation greater and more sensitive than that induced by UTP; similar results were obtained for the sensitivity of inhibition by suramin and reactive blue. Stimulation of the cells with either 2MeSATP or UTP induced a rapid increase in intracellular Ca2+ level, followed by a slow decrease to basal levels, followed by Ca2+ level oscillation. In the absence of extracellular Ca2+, [Ca2+]i responses were quantitatively less and did not show the slow phase and oscillation. Together these results suggest that both P2Y and P2U purinoceptors are expressed in bovine pulmonary artery endothelial cells and are coupled to phospholipase C (PLC) activation and Ca2+ mobilization through pertussis toxininsensitive G proteins.

Characterization of a new genotype II hepatitis delta virus from Taiwan

Three genotypes of HDV, which may be associated with different clinical pictures and epidemiological patterns, have been identified. In contrast to Type I and Type III HDV, both of which have multiple isolates, Type II HDV so far includes only a single isolate (Japan-1) from a low prevalence area (Japan). Recently, Type II has been reported to be the predominant genotype in Taiwan, which is also a low prevalence area, and is associated with less aggresive disease than Type I. However, the sequence and structure of these viruses have not been characterized. The complete characterization of a second member (Taiwan-3 isolate) of the Type II HDV from Taiwan is reported. These two Type II HDV isolates (Taiwan-3 and Japan-1) have 93.8% nucleotide homology and 89.3% amino acid homology, respectively. These shared sequences establish the common characteristics of Type II viruses. Sequence comparisons of various HDV genotypes show that the autocatalytic region of the RNA is relatively conserved between Type I and Type II (88.5-95.6% homology) but is significantly divergent in Type III (76.8-80.3% homology). The hypervariable region (nucleotides 1602-658) of RNA, however, is heterogeneous (64.9-73.0%) among all three genotypes. The delta antigen sequence is also very heterogeneous (64.9-73.0%). Most strikingly, the C-terminal sequence (19 amino acids) of the large delta antigen is almost completely different in each of the three genotypes. The heterogeneity in this region of three HDV genotypes may be a basis for their different biological properties, and the nucleotide sequences of this region can be used to differentiate the different genotypes of HDV. The consensus sequence in the four previously identified conserved domains of HDV RNA is defined more precisely.

Dobutamine stress echocardiography for detecting coronary artery disease

To assess the value of dobutamine stress echocardiography (DSE) to detect coronary artery disease (CAD) and to compare the diagnostic accuracy between DSE and treadmill exercise test (TXT), 104 patients (mean age 58 +/- 12 years) presenting for coronary angiography were prospectively studied. TXT was performed according to the Bruce protocol. Dobutamine (5-40 micrograms/kg/min) was infused in 3-min stages. Digital echocardiograms were recorded on-line at baseline, during low- and peak-dose dobutamine infusion, and at recovery. An echocardiogram positive for CAD was defined as the one showing a new wall motion abnormality (WMA) induced by dobutamine. There were no major complications during the study. Significant CAD (> or = 50% diameter stenosis) was present in 17 of 30 patients who had normal echocardiograms at baseline. The sensitivity for detecting CAD was 76% by TXT and 94% by DSE, and the specificity was only 38% by TXT and 92% by DSE, respectively. Seventy-four patients had localized rest WMAs. Twenty-four had no significant CAD or lesions only confined to regions with abnormal rest wall motion, and 50 had disease remote from these regions. The sensitivity for detection of remote disease was 60% by TXT and 76% by DSE, and the specificity was 75% by TXT and 96% by DSE, respectively. In conclusion, DSE is a safe and accurate diagnostic tool for identifying CAD and for predicting the extent of disease in those who have localized rest WMAs.

A simple and rapid solvent extraction method for determining total lipids in fish tissue

Solvent systems that have been developed for lipid extraction include chloroform-methanol, n-hexane-isopropyl alcohol, and methylene chloride-methanol. The extraction methods are labor intensive, lack precision, or require a large volume of solvent. Correct computation of lipid content calls for full recovery of solvent after extraction, but recovery always is incomplete because of unaccounted solvent residue that remains in jar, filter paper, and homogenized tissue. A rapid and simple extraction method coupled with correct computation was developed for determining total lipids in fish tissue. The method uses chloroform-methanol and an Eberbach blending jar. Variables examined were chloroform-methanol ratio, solvent-to-sample ratio, and phase separation time. Precision was within 0.5%. Conventional computation of lipid content depends on the volume of chloroform measured after filtration. This volume does not include unaccounted solvent residue. Thus, a time-consuming second extraction is required for complete recovery. The mass balance of each extraction and filtration step confirmed that the correct volume of chloroform (measured plus unaccounted) was close to the theoretical volume. The procedure eliminates problems associated with laborious filtration and variation in chloroform volume readings and does not require an exact reading of chloroform volume. Instead it allows use of a theoretical volume, which depends on solvent volume and ratio used.

Sequential evaluation of portal venous hemodynamics by Doppler ultrasound in patients with severe acute hepatitis

OBJECTIVES

Portal hypertension may develop in patients with severe acute hepatitis. Sequential changes of portal venous hemodynamics in acute hepatitis is not well understood. This study evaluated portal hemodynamic changes and prognostic values in patients with severe, acute hepatitis.

METHODS

Doppler studies, liver function tests, and virology studies were done in the inclusion, the 3rd month, and the 6th month for patients with severe, acute hepatitis. An indocyanine green clearance was done in the inclusion. Doppler portal hemodynamic studies were done in the hilar area by an average of two measurements.

RESULTS

A total of 88 consecutive patients was included. Nine of them died. On initial study, fatalities were generally older patients with more delayed indocyanine green clearance, lower portal vein velocity, lower albumin values, higher bilirubin values, longer prothrombin time, and ascites. Using stepwise logistic regression, portal blood flow and prothrombin time were the two independence prognostic factors. By multiple linear regression, portal blood flow was associated with ascites, and average portal blood velocity was associated with bilirubin. During the hospital days, transient, depressed portal blood velocities followed by a hyperdynamic stage were found in survivors. The portal vein velocity changes for fatalities either were kept at a lower level or had a declining pattern.

CONCLUSIONS

Doppler ultrasound detects portal hemodynamic changes for patients with severe, acute hepatitis. Sequential portal hemodynamic studies will be helpful for evaluating patients with severe, acute hepatitis.

Riboflavin-binding protein induces early death of chicken embryos

Maternal riboflavin-binding protein (RfBP) mediates the deposition of riboflavin in avian eggs. A strain of Single-Comb White Leghorn chicken, genetically unable to synthesize RfBP, produces eggs deficient in riboflavin. Embryos in these eggs die on or about 13 of incubation, with severe hypoglycemia and impaired fatty acid oxidation. Injection of free riboflavin prior to incubation allows these embryos to survive and hatch normally. The egg whites of eggs from the RfBP-deficient strain were injected with different relative amounts of riboflavin and RfBP to determine their effects on the developing embryo. Injection of protein-bound riboflavin resulted in a substantial number of the embryos (27%) surviving until the end of the experiment (d 19) with an average weight of 13.7 g, demonstrating that some embryos were able to use the bound riboflavin. In control groups injected with riboflavin alone, 10 of 17 embryos survived until d 19 with an average weight 18.5 g, whereas those injected with saline died between d 10 and 13 with an average weight of 3.8 g. A fourth group, injected with apo-RfBP, produced embryos with an average weight of 0.24 g. This early death suggests that the protein scavenges the small amount of riboflavin normally available to the early embryo. Further studies showed that titration of RfBP-binding sites with exogenous riboflavin lessens this effect. These studies show that although riboflavin-binding protein is essential for the deposition of riboflavin in eggs, its presence in excess can diminish the availability of riboflavin to the chicken embryo.

Age-associated mitochondrial DNA deletions in mouse skeletal muscle: comparison of different regions of the mitochondrial genome

The abundance of mitochondrial DNA (mtDNA) deletions has been shown to increase with age in a number of species and may contribute to the aging process. Estimating the total mtDNA deletion load of an individual is essential in evaluating the potential physiological impact. In this study, we compared three 5-kb regions of the mitochondrial genome: one in the major arc, one in the minor arc, and a third containing the light strand origin of replication. Through PCR analysis of mouse skeletal muscle, we have determined that not all regions produce equal numbers of age-associated deletions. There are, on average, twofold more detectable deletions in the major arc region than in the minor arc region. Deletions that result in the loss of the light strand origin of replication are rarely detected. Furthermore, the mechanism of deletion formation seems to be similar in both the major and minor arcs, with direct repeats playing an important, although not essential, role.

Gastric actinomycosis

A case of actinomycosis of the stomach in a 61-year-old woman is reported. The patient presented to the hospital with a history of epigastric pain, fatigue, poor appetite, constipation and mild fever of 20 days' duration. On physical examination, a tender mass was felt at the epigastrium. Computed tomography (CT) showed a heterogeneously enhanced mass at the posterior wall of the stomach. Upper gastrointestinal series revealed a submucosal mass at the gastric antrum. A malignant tumor was suspected and surgery was recommended. A 5 x 4 x 2 cm mass was found at the posterior wall of the distal gastric antrum. A Billroth II subtotal gastrectomy was performed. Pathologic examination revealed suppuration and sulfur granules in the indurated mass. The patient was subsequently treated with intravenous penicillin-V for 12 days and then with oral penicillin-G for 4 months. She remained well at her last follow-up appointment. Although the initial radiologic findings were nonspecific, CT was of importance in delineating the location and evaluating the extent of the lesion.

Oligomerization of endothelial nitric oxide synthase. Evidence for a dominant negative effect of truncation mutants

Nitric oxide produced by the endothelial isoform of nitric oxide synthase (ecNOS) is a key determinant of vascular tone. In contrast to other nitric oxide synthase (NOS) isoforms, which have been characterized as soluble homodimeric enzymes, ecNOS is predominantly membrane-associated, a feature that has hindered direct biochemical analyses of its oligomeric structure. We investigated ecNOS oligomerization using co-immunoprecipitation experiments in transiently transfected COS-7 cells. When COS-7 cells co-transfected with constructs encoding wild-type ecNOS and an epitope-tagged myristoylation-deficient mutant were biosynthetically labeled with [3H]myristate, the antibody to the epitope tag specifically immunoprecipitated 3H-labeled ecNOS, reflecting enzyme oligomerization. In COS-7 cells transfected with cDNAs encoding epitope-tagged truncation mutants and untagged full-length ec-NOS, the wild-type enzyme could be immunoprecipitated by the antibody to the epitope tag. Co-immunoprecipitation of ecNOS with truncation mutants documented that both N- and C-terminal domains are involved in ecNOS oligomerization. When these truncation mutants are co-expressed with wild-type ecNOS, they exert a marked dominant negative effect on enzyme activity. Since NOS oligomerization itself may be subject to dynamic modulation, the regulation of ecNOS assembly may have implications for NO signaling in the vascular wall.

Giant retroperitoneal hemangiopericytoma

Hemangiopericytomas are rare vascular tumours that are derived from pericytes. Retroperitoneal hemangiopericytomas are usually bulky but clinically silent when diagnosed because of their slow rate of growth. A 49-year-old man, who presented with only vague symptoms of abdominal fullness for several months, was found on computed tomography to have a huge well-defined mass with areas of low attenuation and well-enhanced septa. The tumour was successfully resected and was confirmed to be a malignant retroperitoneal hemangiopericytoma. It measured 30 cm in the greatest dimension. We are prompted to present this case as it is believed to be the largest tumour reported to date.

Monitoring of two hearts in one chest

A 32 year old patient with end-stage cardiomyopathy underwent heterotopic heart transplantation with a small donor heart. Monitoring of this unusual clinical setting of two hearts beating independently in one chest required special technique and scrutinous interpretation so one can differentiate donor heart from recipient heart immediately.

Dobutamine stress echocardiography predicts early wall motion improvement after elective percutaneous transluminal coronary angioplasty

In 24 patients with chronic coronary artery disease, dobutamine stress echocardiography (DSE) was performed within 2 days before and after successful elective percutaneous transluminal coronary angioplasty (PTCA) in a blinded fashion. Patients with ischemic response on DSE before PTCA had significant improvement in the global peak-dose DSE score index after PTCA (1.62 +/- 0.35 to 1.40 +/- 0.29, p < 0.001), whereas patients without ischemic response had no improvement. The positive and negative predictive values of pre-PTCA DSE on early myocardial ischemia relief after angioplasty were 93% and 80%, respectively. In patients showing contractility recruitment during low-dose dobutamine infusion in the DSE before PTCA, there was significant improvement in the global resting wall motion score index in the DSE after PTCA (1.48 +/- 0.43 to 1.34 +/- 0.33, p = 0.004), while patients without contractility recruitment showed no improvement. Again, the positive and negative predictive values of pre-PTCA DSE on early hibernation recovery following angioplasty were 80% and 89%, respectively. In conclusion, DSE in patients with chronic, stable coronary artery disease accurately predicts wall motion improvement after successful angioplasty, and the expected improvement is safely demonstrated early after the procedure.

Continuous noninvasive determination of pulsus paradoxus: a pilot study

OBJECTIVE

To evaluate two methods of continuous, noninvasive monitoring of pulsus paradoxus (PP).

METHODS

A single-subject, nonblind assessment was conducted of the ability of noninvasive monitoring techniques to measure experimentally induced PP. Variable degrees of PP were induced in a healthy adult breathing through a one-way valve to which a series of external airway resistances were added. Intra-arterial pressure (IAP), finger arterial blood pressure (FINAP), pulse oximeter pulse waveform, and chest wall motion were continuously recorded. For each resistance, PP was calculated from the IAP (PPIAP) and the FINAP (PPFINAP) recordings. PP was measured manually (PPmanual) in the opposite arm. The percentage pulse waveform decrease on inspiration (%PWDpleth) was derived from the oximeter pulse waveform. These measurements were compared with the PPIAP. Bias was assessed as the mean difference between PP measures.

RESULTS

PPFINAP was highly correlated with PPIAP (r = 0.96; 95% CI 0.93 to 0.98; p < 0.0001). There was a weak correlation between PPmanual and PPIAP (r = 0.27; 95% CI -0.05 to 0.55; p = 0.0963). The %PWDpleth correlated with PPIAP (r = 0.59, 95% CI 0.32 to 0.78; p = 0.0002). Bias was -1.515 +/- 5.6 mm Hg between PPIAP and PPFINAP; and -4.508 +/- 23.4 mm Hg between PPIAP and PPmanual.

CONCLUSION

An accurate and continuous PP can be measured noninvasively using a FINAP monitor. This method has much better agreement with IAP measurements than do manual measurements. The qualitative information provided by the oximeter pulse waveform is less accurate than that provided by the FINAP monitor, but is a potentially useful screening tool for detection of significant PP.

High levels of mitochondrial DNA deletions in skeletal muscle of old rhesus monkeys

Mitochondrial DNA (mtDNA) deletions increase in abundance with age in many tissues, however, their calculated low levels (usually < 0.1%) in samples from tissue homogenates containing thousands of cells argue against physiologic significance. Through the analysis of defined numbers of cells (skeletal muscle fibers) from rhesus monkeys, we report that the calculated abundance of specific mtDNA deletions is dependent upon the number of fibers analyzed: as the number of fibers decreases, the calculated deletion abundance increases. Also, most mtDNA deletions appear to occur in a mosaic pattern, varying from cell to cell in size, number and abundance. These data support the hypothesis that mtDNA deletions can focally accumulate to high levels contributing to declines in mass and function of aging skeletal muscle.

Isolation and analysis of nephritic-producing immune complexes in Plasmodium berghei-infected mice

A nephritic condition was developed by infecting Swiss Webster albino mice with the malarial parasite Plasmodium berghei NK 65. These animals were tested for urinary protein and the presence of circulating immune complexes using reagent strips and a polyethylene glycol (PEG) precipitation assay. The circulating immune complexes were isolated from the sera using both affinity chromatography and PEG precipitation and from the kidney by acid elution. The isolated complexes were dissociated into their individual components and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The components of the complexes were transferred to nitrocellulose sheets and probed for the presence of malarial antigens using a rabbit anti-P berghei antisera. The overall humoral response to the malarial parasite was evaluated using a radial immunodiffusion assay. The present study confirmed that the malarial-infected animals not only developed the nephritic condition (as evident by the high levels of proteinuria) but also, as indicated by the PEG assay, have the presence of high levels of circulating immune complexes in their serum. The apparent absence in the SDS gels of any abnormal protein bands followed by the inability of the Western blot to reveal any malarial antigens provides some of the strongest evidence to date that these malarial proteins are not directly involved in the circulating immune complexes believed to be responsible for producing this nephritic condition.

Rebleeding rate of various stigmata of recent hemorrhage in peptic ulcer bleeding with different severity

The stigmata of recent hemorrhage (SRH) have been used as a factor for predicting peptic ulcer rebleeding. In previous studies, the rebleeding rate of the visible vessel varied. A hypothesis had been proposed stating that the evolution of the color of the stigmata depends on the point in the healing process of the blood clot on the bleeding ulcer. This retrospective study evaluates the rebleeding rates associated with various colors of stigmata of recent hemorrhage. Of a total of 623 cases of peptic ulcer bleeding (474 male and 149 female, with a mean age of 59 years old), there were 232 gastric ulcers, 369 duodenal ulcers, and 22 stomal ulcers. Stigmata of recent hemorrhage were found in 387 cases (62%). The overall rebleeding rate for those with gastric ulcers was higher than for those with duodenal ulcers (24.2% versus 16.3%, p<0.05), especially for oozing and sentinel clots, the rebleeding rates for active bleeding, blood clots, sentinel clots, and others were 35%, 24.8%, 17%, and 11.3% respectively. The red clot of stigmata of recent hemorrhage had a slightly higher rebleeding rate than the black clot, but the difference was not statistically important. Furthermore, the 5 duodenal ulcers with white sentinel clots experienced no rebleeding. When comparing the rebleeding rates between groups with massive and minor bleeding, a significantly higher rebleeding rate was found in the massive bleeding group (50.5% versus 6.6%, p < 0.001). It can thus be seen that the different types of stigmata of recent hemorrhage represent different stages in the healing process of a bleeding ulcer. A white sentinel clot had a change of not rebleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of delayed treatment with sodium polystyrene sulfonate on serum lithium concentrations in mice

OBJECTIVES

To determine the efficacy of sodium polystyrene sulfonate (SPS) in lowering serum lithium (Li) concentrations. Specifically, to determine the effects of both different doses of SPS and different times to treatment with SPS on serum Li levels.

METHODS

The study was a controlled, single-dose murine trial of SPS on serum Li levels. Male CD-1 mice (n = 525) were given orogastric LiCl and then divided into three main treatment groups: group SPS received a single orogastric administration of SPS in a dose of 5 gm/kg body weight at either 0, 15, 30, 45, or 90 minutes after LiCl; group half-SPS received a single orogastric administration of SPS in a dose of 2.5 gm/kg body weight at times equivalent to those of group SPS; and the control group received orogastric deionized water in a volume equivalent to that of group SPS at 0, 15, 30, 45, or 90 minutes after LiCl. Subgroups of seven to ten mice in each of the four treatment groups were sacrificed at one, two, four, and eight hours after administration of LiCl, and their blood was analyzed for Li concentration.

RESULTS

1) Single doses of SPS significantly lowered serum Li concentrations; 2) this effect was dose-related; 3) the delays in administration of SPS used in this study did not significantly reduce its ability to lower serum Li concentrations; and 4) even when administered after peak serum Li concentrations had been achieved, a single dose of SPS was effective in lowering serum Li levels.

CONCLUSIONS

SPS may be efficacious in the treatment for Li toxicity under certain circumstances, even when there is delay to treatment. Additional study is warranted to further characterize the ability of SPS to alter Li kinetics.