Nonproteolytic neuroprotection by human recombinant tissue plasminogen activator

Human recombinant tissue plasminogen activator (tPA) may benefit ischemic stroke patients by dissolving clots. However, independent of thrombolysis, tPA may also have deleterious effects on neurons by promoting excitotoxicity. Zinc neurotoxicity has been shown to be an additional key mechanism in brain injuries. Hence, if tPA affects zinc neurotoxicity, this may provide additional insights into its effect on neuronal death. Independent of its proteolytic action, tPA markedly attenuated zinc-induced cell death in cortical culture, and, when injected into cerebrospinal fluid, also reduced kainate seizure-induced hippocampal neuronal death in adult rats.

Therapeutic effect of transcatheter oily chemoembolization therapy for encapsulated nodular hepatocellular carcinoma: CT and pathologic findings

An emulsion of iodized oil and doxorubicin hydrochloride was intraarterially injected in 27 patients with encapsulated single nodular hepatocellular carcinoma (HCC). Computed tomography (CT) was performed 1-3 weeks after injection, and the lesions were resected 1-4 weeks thereafter. The percentages of tumor necrosis were evaluated in cut surfaces of resected specimens and were compared with the findings at iodized-oil CT. Six tumors with complete intratumor retention of iodized oil had 98% necrosis, and 21 tumors with incomplete retention had 64% necrosis. Two tumors with complete retention of iodized oil in the surrounding liver had 100% necrosis, while 16 tumors with partial retention and nine tumors without retention of iodized oil in surrounding liver had 74% and 62% necrosis, respectively. Complete retention of iodized oil in the tumor and surrounding liver demonstrated the best therapeutic effects. Evaluation of the pattern and distribution of iodized oil in the tumor and surrounding liver with iodized-oil CT is useful in the assessment of the therapeutic effects of transcatheter arterial embolization in encapsulated nodular HCCs.

Isolation and chronobiological analysis of a neuropeptide pigment-dispersing factor gene in Drosophila melanogaster

In this article, the authors isolate a gene encoding a neuropeptide in Drosophila melanogaster. The substance is called pigment-dispersing factor (PDF), based on one of the roles it plays in crustaceans (the arthropods in which this factor was initially discovered). The PDF-encoding Drosophila gene (pdf) is intronless and present in a single copy per haploid genome. The cytological location of pdf is 97B on the third chromosome. The putative 102-amino-acid precursor (prepro-PDF) consists of a signal peptide and a PDF-associated peptide, followed by the mature PDF. The PDF-associated peptide region of the precursor is highly diverged from those of the crustacean precursors, whereas the primary structure of the mature PDF is conserved in other members of the pigment-dispersing hormone family. A single pdf transcript (ca. 0.8 kb) is expressed predominantly in the head; the expression levels of pdf mRNA are consistently higher in males than in females. Putative pdf homologous transcripts are present in other Drosophila species, which exhibit similar sexual dimorphic expression patterns. Cyclic expression of pdf over the course of the day and night was assessed, but the mRNA exhibited at best very gentle cycling. The pdf expression in two behaviorally arrhythmic mutants were examined; the expression was intact in a period0 mutant but absent in the disconnected mutant.

Lanthanide triflate-catalyzed three component synthesis of alpha-amino phosphonates in ionic liquids. A catalyst reactivity and reusability study

The catalyst reactivity and reusability for the lanthanide triflate-catalyzed three component synthesis of alpha-amino phosphonates have been examined in room temperature ionic liquids, [bmim][X], in which the catalytic activities were very dependent on the counter anion, X, as well as on the phosphorus nucleophile, and moreover, the catalyst immobilized in an ionic liquid was reused several times without any loss of activity.

Right paratracheal air cysts in the thoracic inlet: clinical and radiologic significance

OBJECTIVE

The purpose of our study was to determine the CT appearance and clinical significance of a right paratracheal air cyst at the level of the thoracic inlet.

MATERIALS AND METHODS

Sixty-five consecutive patients with paratracheal air cysts were included in this study. The location, level, size, and shape of the paratracheal air cysts on CT were analyzed. The spirometric data, tracheal indexes, and CT-determined emphysema scores of these patients were compared with those of 60 consecutive patients in a control group.

RESULTS

The air cysts were located at the right posterolateral aspect of the trachea in 64 (98%) of 65 patients and at T1-T2 vertebral levels in 57 (88%) of 65 patients. The mean diameter of the right paratracheal cysts was 10 mm in the axial plane and 14 mm in the vertical plane. CT showed a communicating channel with the trachea in five patients. The ratio of forced expiratory volume obtained in 1 sec to forced vital capacity, and forced expiratory flow between 25% and 75% of vital capacity in patients with paratracheal air cysts, were significantly lower than those of the control group (p < .05). Differences in the tracheal indexes and CT-determined emphysema scores between the study group and the control group were found to be statistically significant (p = .001).

CONCLUSION

The most probable nature of a right paratracheal cyst in the thoracic inlet is tracheal diverticulum with a narrow stalk. The presence of a right paratracheal air cyst on CT could be a sign of obstructive lung disease clinically and of the presence of emphysema radiologically.

Gross quantitative measurements of spinal cord segments in human

STUDY DESIGN

Anatomical measurement.

OBJECTIVE

To obtain quantitative anatomical data on each spinal cord segment in human, and determine the presence of correlations between the measures.

SETTING

Department of Rehabilitation Medicine, Pusan National University Hospital, Pusan, Korea.

METHODS

A total of 15 embalmed Korean adult human cadavers (13 males, two females; mean age 57.3 years) were used. The length of each cord segment was defined as the root attachment length plus the upper inter-root length. After performing a total vertebrectomy, a transverse cut was made at the approximate proximal and distal point of each segment from segment C3 to S5. Sagittal and transverse diameters at the proximal end of each segment, and cross-sectional area, height, and volume of the segment were measured.

RESULTS

The transverse diameter was largest at segment C5, and decreased progressively to segment T8. However, the sagittal diameter of each segment did not change distinctly with the segment. The cervical and lumbar enlargements were determined by the transverse diameters of the segments. Segment C5 had the largest cross-sectional area, at 75.0 mm(2). Segment T6 was the longest, averaging 22.4 mm in length. The longest segment in the cervical spinal cord was segment C5, at 15.5 mm, and segment L1 in the lumbar spinal cord. The volume was largest at segment C5, with a value of 1173.9 mm(3).

CONCLUSIONS

We found characteristic quantitative differences in the values of the parameters measured in the thoracic spinal cord compared to those measured in the cervical and lumbar or lumbosacral spinal cords. These measurements of spinal cord segments appear to provide valuable and practical standard quantitative features and may provide basic data for understanding the morphometric characteristics relevant to pathophysiologic conditions of the spinal cord.

Keratocytes generate traction forces in two phases

Forces generated by goldfish keratocytes and Swiss 3T3 fibroblasts have been measured with nanonewton precision and submicrometer spatial resolution. Differential interference contrast microscopy was used to visualize deformations produced by traction forces in elastic substrata, and interference reflection microscopy revealed sites of cell-substratum adhesions. Force ranged from a few nanonewtons at submicrometer spots under the lamellipodium to several hundred nanonewtons under the cell body. As cells moved forward, centripetal forces were applied by lamellipodia at sites that remained stationary on the substratum. Force increased and abruptly became lateral at the boundary of the lamellipodium and the cell body. When the cell retracted at its posterior margin, cell-substratum contact area decreased more rapidly than force, so that stress (force divided by area) increased as the cell pulled away. An increase in lateral force was associated with widening of the cell body. These mechanical data suggest an integrated, two-phase mechanism of cell motility: (1) low forces in the lamellipodium are applied in the direction of cortical flow and cause the cell body to be pulled forward; and (2) a component of force at the flanks pulls the rear margins forward toward the advancing cell body, whereas a large lateral component contributes to detachment of adhesions without greatly perturbing forward movement.

Takayasu arteritis: evaluation of mural changes in the aorta and pulmonary artery with CT angiography

PURPOSE

To evaluate mural changes in the aorta and pulmonary artery in Takayasu arteritis by using computed tomographic (CT) angiography.

MATERIALS AND METHODS

CT angiography was prospectively performed in 12 women with Takayasu arteritis and in 10 healthy adults. Scanning included three distinct phases: precontrast (before administration of contrast material), arterial, and delayed.

RESULTS

Precontrast transverse images revealed a high-attenuation aortic wall (10 patients) and mural calcifications in the aorta (nine patients). Arterial-phase images revealed circumferential wall thickening of 1-4 mm in all patients and enhancement in five patients with active disease. Delayed-phase CT revealed circumferential enhancement in eight patients. A concentric, low-attenuation ring was also identified inside the aorta on the arterial-phase (two patients) and delayed-phase (three patients) images. In the pulmonary artery, wall thickening was revealed with early and delayed enhancement in two patients.

CONCLUSION

CT angiography may demonstrate changes in the vascular wall in patients with Takayasu arteritis.

Liver abscess after transcatheter oily chemoembolization for hepatic tumors: incidence, predisposing factors, and clinical outcome

PURPOSE

To evaluate the incidence of, predisposing factors for, and clinical outcome of liver abscess developing in patients with hepatic tumors after transcatheter oily chemoembolization (TOCE).

MATERIALS AND METHODS

During the past 6-year period, 2,439 patients with hepatic tumors underwent a total of 6,255 TOCE procedures. With a retrospective review of medical records, the authors evaluated the occurrence of liver abscess, the statistical significance of potential predisposing factors including portal vein obstruction, metastatic tumors, biliary abnormalities (type 1, simple biliary obstruction; type 2, status prone to ascending biliary infection), malignant gastrointestinal mucosal lesions, and additional gelatin sponge particle embolization in liver abscess formation, and the clinical outcome of abscess.

RESULTS

Fifteen liver abscesses occurred in 14 patients (0.2%). Liver abscesses developed in three of 987 (0.3%) TOCE procedures for portal vein obstruction, three of 114 (2.6%) procedures for metastatic tumors, one of 49 (1.8%) for type 1 biliary abnormality, four of 55 (7.4%) for type 2 biliary abnormality, two of 18 (11.1%) for malignant gastrointestinal mucosal lesion, and nine of 2,108 (0.4%) for additional gelatin sponge particle embolization. Univariate and multivariate statistical analysis showed that type 2 biliary abnormality was a significant predisposing factor. The mortality related to liver abscess occurred in two patients (13.3%). Thirteen liver abscesses were successfully treated with parenteral antibiotics and percutaneous catheter drainage. However, irreversible deterioration of liver function occurred in two patients. Two of nine further TOCE procedures in three patients caused recurrent septicemia and liver abscess.

CONCLUSION

The biliary abnormality prone to ascending biliary infection was the most important predisposing factor to the development of liver abscess after TOCE. Postembolic liver abscess could be effectively managed with percutaneous catheter drainage.

Disruption of synaptic transmission or clock-gene-product oscillations in circadian pacemaker cells of Drosophila cause abnormal behavioral rhythms

To study the function of clock-gene-expressing neurons, the tetanus-toxin light chain (TeTxLC), which blocks chemical synaptic transmission, was expressed under the control of promoters of the clock genes period (per) and timeless (tim), each fused to GAL4-encoding sequences. Although TeTxLC did not affect cycling of a clock-gene product at the gross level, it disrupted the rhythmic behavior of adult Drosophila. In constant darkness, the proportion of rhythmic flies was reduced in flies expressing active TeTxLC compared to controls, including those expressing inactive toxin. The behavior of TeTxLC-expressing flies was less synchronized to light:dark cycles than that of controls. To determine which neurons are responsible for these effects on behavior, the toxin was also expressed in restricted subsets of per/tim-expressing, laterally located pacemaker neurons by expressing TeTxLC under the control of a driver in which GAL4-encoding sequences are fused to the promoter of the pigment dispersing factor (pdf) gene. pdf-gal4-driven TeTxLC expression had relatively little effect on behavioral rhythms, implying that per/tim neurons other than pdf-expressing lateral neurons participate in the generation of rhythmic behavior. In another set of experiments, period gene products were expressed under the control of per-gal4 or tim-gal4. This resulted in an increased level of PER protein in many brain cells and reduction of bioluminescence cycling reported by a per-luciferase transgene, especially in the case of per expression affected by tim-gal4. This indicates a disruption of the transcriptional feedback loop that is a part of the oscillatory mechanism underlying Drosophila's circadian rhythms. Consistent with this molecular defect, the proportion of rhythmic individuals in constant darkness was subnormal in flies expressing PER under the control of tim-gal4, and their behavior in light:dark cycles was abnormal.

Identification of three genetic loci controlling leaf senescence in Arabidopsis thaliana

Four mutants that show the delayed leaf senescence phenotype were isolated from Arabidopsis thaliana. Genetic analyses revealed that they are all monogenic recessive mutations and fall into three complementation groups, identifying three genetic loci controlling leaf senescence in Arabidopsis. Mutations in these loci cause delay in all senescence parameters examined, including chlorophyll content, photochemical efficiency of photosystem II, relative amount of the large subunit of Rubisco, and RNase and peroxidase activity. Delay of the senescence symptoms was observed during both age-dependent in planta senescence and dark-induced artificial senescence in all of the mutant plants. The results indicate that the three genes defined by the mutations are key genetic elements controlling functional leaf senescence and provide decisive genetic evidence that leaf senescence is a genetically programmed phenomenon controlled by several monogenic loci in Arabidopsis. The results further suggest that the three genes function at a common step of age-dependent and dark-induced senescence processes. It is further shown that one of the mutations is allelic to ein2-1, an ethylene-insensitive mutation, confirming the role of ethylene signal transduction pathway in leaf senescence of Arabidopsis.

Antiobesity effect of trans-10,cis-12-conjugated linoleic acid-producing Lactobacillus plantarum PL62 on diet-induced obese mice

AIMS

To observe the antiobesity activity of trans-10,cis-12-conjugated linoleic acid (CLA)-producing lactobacillus in mice.

METHODS AND RESULTS

Lactobacillus plantarum PL62, which can grow in the presence of linoleic acid, was selected and studied. The culture supernatant of Lact. plantarum PL62 contained trans-10,cis-12-conjugated linoleic acid (6.4 microg ml(-1)), and the crude enzyme prepared from washed cells produced trans-10,cis-12 CLA (1395 microg mg(-1) protein). Lact. plantarum PL62 reduced the weights of epididymal, inguinal, mesenteric, and perirenal white adipose tissues and significantly reduced the blood levels of total glucose and body weights of mice (P<0.01).

CONCLUSIONS

trans-10,cis-12-CLA-producing Lact. plantarum PL62 can exert the same antiobesity activity as trans-10,cis-12-CLA in mice.

SIGNIFICANCE AND IMPACT OF THE STUDY

trans-10,cis-12-CLA-producing Lactobacillus can be a replacement for CLA for obesity treatment via the continuous production of trans-10,cis-12-CLA. The results provide a novel opportunity to develop foods with antiobesity activity.

Power versus conventional color Doppler sonography: comparison in the depiction of vasculature in liver tumors

PURPOSE

To compare power and conventional color Doppler sonography in the depiction of the intratumoral vasculature of hemangiomas, hepatocellular carcinomas (HCCs), and metastases of the liver.

MATERIALS AND METHODS

Thirty-two patients with liver tumors (12 hemangiomas, 11 HCCs, and nine metastases) were prospectively evaluated with power and conventional color Doppler sonography by using a 2-4-MHz convex probe with 2-MHz Doppler frequency. Power Doppler sonography was performed with a 75%-88% gain. Conventional color Doppler sonography was performed with a 55%-75% gain and a pulse repetition frequency of 700 Hz. Power Doppler signals and color Doppler signals interrogated in one plane were analyzed by two radiologists, who subjectively rated power Doppler sonography as superior, equal, or inferior to color Doppler sonography.

RESULTS

Overall, power Doppler sonography was superior to color Doppler sonography in 18 patients and equal in 14 (P < .01). In hemangiomas, power Doppler sonography was superior to color Doppler sonography in 10 patients and equal in two (P < .01). In HCCs, power Doppler sonography was superior to color Doppler sonography in four patients and equal in seven (P > .05). In metastases, power Doppler sonography was superior to color Doppler sonography in four patients and equal in five (P < .05).

CONCLUSION

Power Doppler sonography is more sensitive than color Doppler sonography in the depiction of the vasculature of liver tumors, particularly in hemangiomas.

Arterial manifestations of Behçet disease

Behçet disease is an uncommon systemic process that appears most often in the third or fourth decade of life. It is characterized by recurrent orogenital ulcers and ocular and cutaneous inflammatory lesions. Cardiovascular involvement, which may be arterial or venous, is rare but carries a particularly poor prognosis. Three new cases are reported, and they are characterized by typical orogenital and cutaneous manifestations and associated severe vasculitis. The arterial findings in these cases were occlusions and aneurysms and pseudoaneurysms of the aorta and pulmonary, brachiocephalic, and visceral arteries. From these cases and those previously reported, arterial involvement in Behçet disease can be characterized by saccular aneurysms or occlusions of multiple large vessels in young adults.

Nutcracker syndrome: diagnosis with Doppler US

PURPOSE

To assess diagnosis of the nutcracker (renal vein entrapment) syndrome with Doppler ultrasonography (US).

MATERIALS AND METHODS

Doppler US findings in 16 patients with the nutcracker syndrome and in 18 healthy control subjects were compared. The anteroposterior (AP) diameter and peak velocity (PV) were measured at the hilar portion of the left renal vein (LRV) and at the LRV between the aorta and the superior mesenteric artery.

RESULTS

The mean AP diameters of the LRV were 10.0 mm +/- 2.0 (standard deviation) and 1.9 mm +/- 1.0 (ratio, 5.0 +/- 2.3) in the patient group and 7.2 mm +/- 1.8 and 2.3 mm +/- 0.6 (ratio, 3.3 +/- 1.1) in the control group. The PVs at the two locations were 14.2 cm/sec +/- 2.5 and 110.7 cm/sec +/- 35.8 (ratio, 7.9 +/- 2.7) in the patient group and 18.6 cm/sec +/- 3.7 and 50.9 cm/sec +/- 27.9 (ratio, 2.8 +/- 1.5) in the control group. Differences in AP diameter and PV were statistically significant between the two groups (P < .01).

CONCLUSION

Doppler US of the LRV with measurement of the AP diameter and PV may be useful in diagnosing the nutcracker syndrome.

Dermatomyositis: correlative MR imaging and P-31 MR spectroscopy for quantitative characterization of inflammatory disease

Magnetic resonance (MR) imaging and phosphorus-31 MR spectroscopy were used to examine four patients with dermatomyositis and five control subjects. T2-weighted images of the thigh muscles of patients showed increased signal intensity, with focal and inhomogeneous involvement predominantly in the vastus lateralis and secondarily in the vastus intermedius and vastus medialis. T1 and T2 values of the vastus lateralis in patients were significantly higher than those of the control subjects. T1 values of the rectus femoris and biceps femoris with more generalized inflammation were moderately elevated but still significantly higher than those of the control subjects. P-31 MR spectra of the quadriceps muscles were obtained during rest, during exercise at two graded levels, and in recovery. Concentrations of adenosine triphosphate and phosphocreatine (PCr) in the diseased muscles were 30% below normal values, and the inorganic phosphate/PCr ratios were increased in the patients' muscles at rest and throughout exercise. The T1 and T2 values as well as the P-31 metabolite data correlated with symptoms and clinical assessment.

Hepatocellular carcinoma and portal vein invasion: results of treatment with transcatheter oily chemoembolization

OBJECTIVE

Our objective was to evaluate the efficacy and safety of transcatheter oily chemoembolization therapy in a series of patients with hepatocellular carcinoma and portal vein invasion.

MATERIALS AND METHODS

We retrospectively analyzed the results of transcatheter oily chemoembolization for 110 patients with hepatocellular carcinoma invading major portal branches. The Child's classes were A for 94 patients and B for 16. The main portal vein was partially (n = 33) or completely (n = 15) invaded in 48 patients, the right portal vein was invaded in 36, and the left portal vein was invaded in 26. Oily chemoembolization was performed with an emulsion of iodized oil and doxorubicin hydrochloride. Gelatin sponge particle embolization was added for 78 patients. Seventy-one patients underwent multiple treatment sessions.

RESULTS

Our initial findings showed that 31 patients had complete or partial remission, with an overall median survival time of 6 months. The cumulative survival rates were 48% (6 months), 30% (1 year), 18% (2 years), and 9% (3 years). The parenchymal tumor extent was the most significant predicting factor for complications and efficacy of therapy. Of 33 patients with a parenchymal tumor limited to one or two segments of a hepatic lobe, 22 had complete or partial remission, with a median survival time of 22 months; this survival time was significantly longer than that (5 months) for 77 patients with a more extensive tumor (p < .0001). Hepatic insufficiency developed in 10 patients, and three of them died within 1 month after chemoembolization. All 10 patients had an extensive parenchymal tumor involving more than two hepatic segments, and four had impaired hepatic functional reserve of Child's class B.

CONCLUSION

When a tumor is limited in extent and hepatic function is preserved, transcatheter oily chemoembolization is effective and safe for the palliation of hepatocellular carcinoma and major portal vein invasion. However, when a parenchymal tumor is extensive, chemoembolization is associated with a poor response and a risk of hepatic failure.

Pulmonary oil embolism after transcatheter oily chemoembolization of hepatocellular carcinoma

The medical records of 336 patients with hepatocellular carcinoma who underwent transcatheter oily chemoembolization (TOCE) performed via the hepatic artery were retrospectively reviewed to ascertain the occurrence of symptomatic pulmonary oil embolism. In 14 patients, more than 20 mL of iodized oil was administered. In six of these 14 patients, respiratory symptoms of cough, hemoptysis, and dyspnea developed 2-5 days after TOCE, and their chest radiographs showed diffuse bilateral pulmonary parenchymal infiltrate. Their arterial partial pressure of oxygen while they breathed room air ranged from 39 to 60 mm Hg during maximum hypoxemia. The symptoms, arterial hypoxemia, and chest radiographic abnormalities completely cleared 10-28 days after TOCE in the five patients who survived. One patient died 10 days after TOCE because of respiratory arrest with a progression of pulmonary infiltrate. Although histopathologic proof is lacking, it is concluded that massive pulmonary embolization of iodized oil was the primary cause of the clinical and radiographic manifestations in these six patients.

Differential expression of senescence-associated mRNAs during leaf senescence induced by different senescence-inducing factors in Arabidopsis

Four cDNA clones, named pSEN2, pSEN3, pSEN4, and pSEN5, for mRNAs induced during leaf senescence in Arabidopsis thaliana were characterized. The clones were isolated from a cDNA library of detached leaves incubated in darkness for 2 days to accelerate senescence, first by differential screening and then by examining expression of the primarily screened clones during age-dependent leaf senescence. Transcript levels detected by these cDNA clones, thus, were up-regulated in an age-dependent manner and during dark-induced leaf senescence. In contrast, when leaf senescence was induced by ethylene, ABA or methyljasmonate, the transcript level detected by the clones was differentially regulated depending on the senescence-inducing hormones. The transcript level for pSEN4 increased during senescence induced by all three hormones, while the transcript detected by the pSEN2 clone did not increase during senescence induced by ethylene. The transcript level for pSEN5 was increased upon ABA-induced senescence but decreased during ethylene-induced senescence. The pSEN3 clone detected multiple transcripts that are differentially regulated by these factors. The results show that, although the apparent senescence symptoms of Arabidopsis leaf appear similar regardless of the senescence-inducing factors, the detailed molecular state of leaf cells during senescence induced by different senescence-inducing factors is different. The pSEN3 clone encodes a polyubiquitin and the pSEN4 clone encodes a peptide related to endoxyloglucan transferase. This result is consistent with the expected roles of senescence-induced genes during leaf senescence.

Magnetic resonance imaging and P-31 magnetic resonance spectroscopy provide unique quantitative data useful in the longitudinal management of patients with dermatomyositis

OBJECTIVE

To evaluate the utility of magnetic resonance imaging (MRI) and P-31 magnetic resonance spectroscopy (MRS) in the longitudinal management of patients with dermatomyositis (DM).

METHODS

The study group consisted of 11 patients, including 3 children, all of whom had a clinical diagnosis of DM. A control group of 8 subjects was studied simultaneously. MRI included images as well as calculations of T1 and T2 relaxation times. The P-31 MRS protocol evaluated metabolic status (i.e., inorganic phosphate/phosphocreatine ratios and phosphocreatine and ATP levels) during rest, exercise, and recovery.

RESULTS

T2-weighted images of the thigh muscles showed inflammation even when serum creatine phosphokinase levels were in the normal range. Metabolic abnormalities, which were accentuated with exercise, were found in 10 patients. In some individuals, bioenergetic defects preceded other changes and persisted after resolution of inflammation. In general, clinical impressions correlated with MRI/MRS data.

CONCLUSION

MRI and MRS provide unique data which are quantitative and which cannot be obtained from routine laboratory tests. These MR evaluations appear to be of value in assessing the status of DM patients during treatment with steroids and immunosuppressive drugs.

Mediastinal tuberculous lymphadenitis: CT manifestations

An analysis was done of computed tomographic (CT) scans of 23 Korean patients who had presented with a mediastinal or hilar mass on plain chest radiographs and had subsequently been found to have tuberculous lymphadenitis. Most patients were young adults. Findings of pulmonary tuberculosis were seen on plain radiographs in 14 patients. On CT, findings were of an overwhelming preponderance of involvement of the right paratracheal and tracheobronchial nodes. After injection of contrast medium, nodes larger than 2 cm in diameter invariably showed central areas of relative low density and peripheral rim enhancement. Enhanced walls were usually irregular in thickness. Some smaller nodes did not show low-density areas, but instead showed varying degrees of homogeneous enhancement. Although metastatic nodes can be of low density, experience in this study suggests that mediastinal lymphadenopathy in a young adult with the CT findings described above is characteristic enough to support a diagnosis of tuberculosis.

Truncated and native insulinlike growth factor I enhance mucosal adaptation after jejunoileal resection

It has been shown previously that insulinlike growth factors (IGFs) stimulate the proliferation of intestinal crypt cells in vitro. To examine the in vivo effects of IGF-I on mucosal adaptation, three groups of Sprague-Dawley rats underwent 80% jejunoileal resection. Miniosmotic pumps were then inserted under the skin immediately after resection to deliver vehicle (resected control), 1.5 mg/kg per day of IGF-I, or 1.5 mg/kg per day of des-(1-3)-IGF-I (des-IGF-I). Des-IGF-I is a truncated form of IGF-I that binds as well to type I IGF receptors but less tightly to several forms of IGF-binding proteins (IGFBPs) than IGF-I. Ad libitum food intake did not differ among the three resected groups. Body weight gains were greater in animals receiving des-IGF-I than in those receiving IGF-I, which were greater than resected controls. All animals were killed 7 days postoperatively, and the remaining small intestine was removed and divided at the anastomotic site. Both IGF-I and des-IGF-I induced hyperplasia (increased DNA and protein content) in the duodenojejunum but not in the ileum. IGF-I and des-IGF-I were equally active. In contrast, sucrase, maltase, and leucine aminopeptidase activities were greater only in the ileum of animals receiving IGF-I and des-IGF-I than in resected controls. Although more potent in stimulating overall body weight gain, des-IGF-I was not more potent than IGF-I when duodenal and ileal responses were determined. IGF infusion (IGF-I greater than des-IGF-I) increased the levels of circulating IGFBP-3 and IGFBP-2, which may act to modulate the biological effectiveness of the infused peptides. These results suggest that both IGF-I and des-IGF-I may have potential as therapeutic agents for short bowel patients.

The human acid ceramidase gene (ASAH): structure, chromosomal location, mutation analysis, and expression

Acid ceramidase (AC) is the lysosomal enzyme that degrades ceramide into sphingosine and fatty acid. A deficiency in human AC activity leads to the lysosomal storage disorder, Farber disease (FD). The human AC gene (HGMW-approved symbol ASAH) was cloned and characterized, revealing an organization similar to that of the murine AC gene. The human gene spans about 30 kb in length and contains 14 exons ranging in size from 46 to 1201 bp. The exon/intron junctions were determined and found to follow the GT-AG rule. The putative promoter region had a GC content over 60%, lacked a TATA box, and contained several sequences matching transcription factor binding sites, including nine SP-1 sites, one AP-1 site, and three CACC boxes. The promoter activity of a 475-bp fragment from within this region was demonstrated by chloramphenicol acyltransferase assays. Northern blotting revealed variable expression of the human AC RNA; i.e., expression of the major 2.4-kb transcript was high in heart and kidney, followed by lung and placenta, but low in pancreas, liver, brain, and skeletal muscle. Two minor AC transcripts of 1.7 and 1.2 kb also were detected in heart and skeletal muscle. The human AC gene was mapped to the chromosomal region 8p21.3-p22 by in situ hybridization and FISH analyses, syntenic with the mouse chromosomal location. Finally, three new missense mutations, E138V, R254G, and P362R, were identified in the human AC gene from FD patients. Mutant AC cDNAs containing these point mutations were constructed and examined using the FLAG-tagged expression system. Although the levels of protein expression for these mutant ACs were about equivalent to that of the controls, their enzymatic activity was markedly reduced, confirming their authenticity.

Supplemental effect of probiotic Bacillus subtilis B2A on productivity, organ weight, intestinal Salmonella microflora, and breast meat quality of growing broiler chicks

One-day-old Ross 308 male broiler chicks were used to investigate the additive effect during growth of Bacillus subtilis B2A derived from soil samples on productivity, organ weight, intestinal Salmonella microflora, and breast meat quality. Five hundred seventy-six birds (46 ± 0.5 g) were fed 3 different levels of B. subtilis B2A (1.1 × 10(4), 1.0 × 10(5), and 1.0 × 10(6) cfu), in a basal diet based on corn-soybean meal, for 28 d. In the current study, feed intake and feed conversion during 1 to 28 d showed significant improvement as dietary B. subtilis B2A increased from 1.1 × 10(4) to 1.0 × 10(6) cfu (linear, P < 0.05). All blood parameters, such as white blood cells, red blood cells, and lymphocyte and haptoglobin concentrations, were not influenced by B. subtilis B2A added into the diet; however, the weights of the bursa of Fabricius were significantly increased linearly in B. subtilis B2A-fed groups (P < 0.05). Bacillus subtilis B2A supplementation was associated with reduced intestinal Salmonella burden (linear and quadratic, P < 0.05). Breast meat pH and color were not affected by B. subtilis B2A, but 1 d drip loss was decreased (linear, P < 0.05). Our observations suggest that B. subtilis B2A benefits productivity and reduces Salmonella in broilers.