Transvaginal sonography in the diagnosis of acute appendicitis.

OBJECTIVES: To evaluate transvaginal sonography with power Doppler capacity in the diagnosis of acute appendicitis and in discriminating appendicitis from pelvic inflammatory disease. PATIENTS AND METHODS: We describe transvaginal sonographic findings of six women with acute appendicitis selected from 31 women seen in an emergency room setting for clinically suspected pelvic inflammatory disease. The study population underwent gray-scale transvaginal sonography, and specific sonographic landmark findings for acute appendicitis and pelvic inflammatory disease were used. Hyperemia of any infectious complex was identified by power Doppler. Laparoscopy was performed after transvaginal sonography and was used as the gold standard. RESULTS: Laparoscopy showed acute appendicitis in six (19%) of the 31 patients. A thick walled non-compressible gas-containing tubular structure with a diameter exceeding 6 mm was seen by transvaginal sonography in four of the six cases, consistent with uncomplicated appendicitis. A heterogeneous complex with surrounding hyperechogenic soft tissue was seen in two cases with gangrenous appendicitis. Power Doppler detected hyperemia in all six cases. Normal adnexal structures were imaged next to the inflamed appendix. The sonographic criteria consistent with acute appendicitis were clearly different from those of acute pelvic inflammatory disease. CONCLUSIONS: Transvaginal sonography provides an opportunity to distinguish between appendicitis and acute pelvic inflammatory disease. Prospective trials are needed in order to evaluate the impact of transvaginal sonography in the diagnosis of acute appendicitis.     

Free amino acids in plasma during experimental infection of mice with the MHV-3 strain of mouse hepatitis virus.

The concentrations of total free amino acids, single free amino acids, urea, and ammonia were determined in plasma of mice during experimental infection with the MHV-3 strain of mouse hepatitis virus. Analysis of free amino acids was done by ion-exchange resin chromatography under conditions that allowed the use of a single chromatographic column, separation of glutamine and asparagine, and an accelerated rate of chromatography. The results showed that as early as 6 hr after infection there was a decrease in the concentration of several free amino acids as well as in the total concentration of free amino acids in plasma. For most of the amino acids the decrease persisted until 48 hr. Only at 72 hr, during severe cytolysis, did the concentration of amino acids increase significantly. It is suggested that the decrease during the initial phases of the infection may be due to a thermolabile factor that is produced by circulating leukocytes and that effects a flow of free amino acids from the plasma toward the liver. The final increase in concentration of several free amino acids reflects the cytolytic damage to the liver caused by the virus.     

Spread of T lymphocyte immune responses to myelin epitopes with duration of multiple sclerosis

Although the primary cause of multiple sclerosis (MS) is unclear, evidence supports a role for autoimmune attack of myelin by T lymphocytes. However, it has been difficult to relate patterns of autoimmunity to pathogenesis. In mouse models, the case has been made for relapsing and remitting disease driven by epitope spread: an initial lesion leads to presentation of central nervous system antigens, in turn triggering the next wave of autoimmune T cells of different specificity, the response thus broadening. Few studies have been done to determine whether these events could be important over the longer time scale of human disease. We compared T cell responses with a panel of myelin epitopes in clinically isolated syndrome patients with a first attack, patients with MS with a mean disease duration of 0.95 years, and patients with MS having a mean disease duration of 15.9 years. T cells from patients with long-term disease recognize more myelin epitopes than patients with recent-onset disease. The epitope myelin basic protein 131-149, in particular, was more commonly recognized by patients with long-term disease. The data support the notion that the T cell response in MS broadens with time and is thus implicated in the ongoing pathogenic process. However, there was no clear correlation between disease severity and number of epitopes recognized. This may argue against a simple causal role of epitope spread in driving progression, as has been suggested in experimental allergic encephalomyelitis.     

Paradoxical CD4+ T-cell decline in HIV-infected patients with complete virus suppression taking tenofovir and didanosine

BACKGROUND: Tenofovir (TDF) and didanosine (ddI) are both adenosine analogues with convenient posology, strong potency and a relatively high genetic barrier for resistance. The popularity of this combination, however, has been questioned due to concerns about pharmacokinetic interactions and increased risk of pancreatitis and hyperglycemia. Less information is available about other possible side effects. PATIENTS AND METHODS: HIV-infected individuals who initiated a protease inhibitor-sparing regimen between September 2002 and June 2003 at five hospitals, and had at least one subsequent visit within the next 12 months, always with complete virus suppression, were retrospectively assessed. Only drug-naive individuals and patients who simplified a prior successful antiretroviral regimen were analysed. RESULTS: Outcomes were analysed in 570 individuals according to treatment modality (98 drug-naive versus 472 simplified); the nucleoside analogue (NA) backbone (298 with TDF + ddI, 88 with ddI, 44 with TDF, and 140 with neither ddI nor TDF); and the third agent used (378 with non-nucleoside analogues versus 192 with NA). Significant CD4+ T-cell declines were seen in patients taking ddI + TDF with respect to all other NA combinations, including ddI or TDF separately. Patients exposed to high ddI doses or taking a third NA showed more pronounced CD4 declines. Plasma levels of ddI correlated with the extent of CD4+ T-cell loss. CONCLUSION: Patients receiving ddI + TDF-based combinations show CD4+ T-cell declines despite achieving complete virus suppression. This effect generally progresses with time. An imbalance in adenosine metabolites within CD4+ T lymphocytes may explain this phenomenon, which resembles the genetic purine nucleoside phosphorylase deficiency syndrome.     

MDCT in Pancreatic adenocarcinoma: prediction of vascular invasion and resectability using a multiphasic technique with curved planar reformations

OBJECTIVE: The objective of our study was to determine the negative predictive value of MDCT with curved planar reformations for detecting vascular invasion and predicting overall resectability in patients with pancreatic adenocarcinoma. MATERIALS AND METHODS: Imaging findings related to vascular invasion and overall tumor resectability in 25 patients who underwent contrast-enhanced biphasic MDCT evaluation were correlated with actual vessel invasion and overall resectability determined at surgery and pathologic examination. The presence of vascular invasion was assessed in 110 major peripancreatic vessels in 22 patients who underwent resection. RESULTS: On MDCT, 23 (92%) of 25 patients were deemed to have resectable pancreatic adenocarcinoma. The tumors in the remaining two (8%) were considered not resectable because of the presence of vascular invasion (which was confirmed in only one patient at surgery). Of those 23 patients deemed to be candidates for curative resection on the basis of MDCT results, 20 were found to have resectable adenocarcinoma at time of surgery, yielding a negative predictive value for MDCT of 87% (20/23 patients) for overall resectability. In the other three patients, adenocarcinoma was deemed to be unresectable because of small metastases to the liver (two patients) or to the peritoneum (one patient) discovered at surgery. For detection of vascular invasion, MDCT yielded a negative predictive value of 100% (108/108 vessels) with no false-negative findings and an accuracy of 99% (109/110 vessels) with 108 true-negative findings, one true-positive finding, and one false-positive finding. CONCLUSION: Our preliminary data on MDCT show that the technique has excellent negative predictive value for vascular invasion and good negative predictive value for overall tumor resectability in patients with pancreatic adenocarcinoma, suggesting an improvement over previous results reported using single-detector CT. The problem of undetected micrometastases to the liver and peritoneum remains.     

High incidence of extended-spectrum beta-lactamases among outpatient clinical isolates of Escherichia coli: a phenotypic assessment of NCCLS guidelines and a commercial method

The production of extended-spectrum beta-lactamases (ESBLs) among 357 clinical isolates of Escherichia coli and 175 of Klebsiella spp. was studied using both the National Committee for Clinical Laboratory Standards disk diffusion method and the semiautomated Wider system. We highlight the predominance of E. coli (50, 92.6%) among positive samples and the largely outpatient origin of these (40, 80%), including 39 samples of urine (97.5%) and one of urethral exudate. There were only four ESBL-producing isolates of Klebsiella spp. (7.4%), and three were in outpatient urine samples (75%, 2 K. oxytoca and 1 K. pneumoniae). The positive and negative predictive values for the Wider system were 81% and 98.5%, respectively. We stress the high incidence of ESBL in our setting, the predominance of cases in the outpatient setting, and the acceptable detection of ESBL by means of the Wider system in E. coli and Klebsiella spp.     

Effect of glucomannan and the dosage form on ethinylestradiol oral absorption in rabbits

To the beneficial properties of dietary fiber in human health, several disadvantages can be added as the possible modification of the bioavailability of other drugs when administered by the oral route. In this study, the influence of glucomannan in the oral bioavailability of ethinyl estradiol (EE), when administered to female rabbits in two different dosage forms (enteric capsules and dispersed in water), was established. To carry out the study, three groups of six animals each were used. All animals received 1 mg kg(-1) oral EE, and rabbits in groups 2 and 3 received 1.5 g glucomannan dispersed in water or in enteric capsules, respectively, immediately before EE. When comparing the results obtained after the administration of EE/glucomannan dispersed in water with those obtained after the administration of this estrogen without fiber, we can see that Cmax is 1.4 times lower, AUC 1.9 times lower and that tmax is identical (10 min). However, after the administration of fiber in enteric capsules, AUC and Cmax are higher (4.1 and 7.8 times, respectively) than when the estrogen was administered alone, and also, there is a delay in tmax (20 min). After the administration of glucomannan in the enteric capsule, the fiber forms, as in the stomach, a highly viscous solution in the gut that would limit EE access to the mucosal surface delaying its absorption. However, this effect could be compensated by a reduction of EE metabolism in the intestinal wall, leading to a higher absorption of the estrogen.     

Effect of adrenomedullin on c-Met receptor expression after reserpine-induced gastric damage in the rat

Here, we show an increase in c-Met receptor expression during reserpine-induced gastric damage in the rat, as assessed by immunohistochemistry. Pretreatment of animals with adrenomedullin prevented this increase in c-Met expression. c-Met immunoreactivity was localized in gastric glands. c-Met immunoreactivity was associated with increased phosphorylation of c-Met receptor and extracellular signal-regulated kinase (ERK(1/2)). Our results suggest that both adrenomedullin and c-Met act as parallel defence mechanisms during pharmacologically induced gastric mucosa injury.