Complete nucleotide sequence of pig (Sus scrofa) mitochondrial genome and dating evolutionary divergence within Artiodactyla

The complete nucleotide sequence of the pig (Sus scrofa) mitochondrial genome, containing 16613bp, is presented in this report. The genome is not a specific length because of the presence of the variable numbers of tandem repeats, 5'-CGTGCGTACA in the displacement loop (D-loop). Genes responsible for 12S and 16S rRNAs, 22 tRNAs, and 13 protein-coding regions are found. The genome carries very few intergenic nucleotides with several instances of overlap between protein-coding or tRNA genes, except in the D-loop region. For evaluating the possible evolutionary relationships between Artiodactyla and Cetacea, the nucleotide substitutions and amino acid sequences of 13 protein-coding genes were aligned by pairwise comparisons of the pig, cow, and fin whale. By comparing these sequences, we suggest that there is a closer relationship between the pig and cow than that between either of these species and fin whale. In addition, the accumulation of transversions and gaps in pig 12S and 16S rRNA genes was compared with that in other eutherian species, including cow, fin whale, human, horse, and harbor seal. The results also reveal a close phylogenetic relationship between pig and cow, as compared to fin whale and others. Thus, according to the sequence differences of mitochondrial rRNA genes in eutherian species, the evolutionary separation of pig and cow occurred about 53-60 million years ago.

Evaluation of proliferative activity in middle ear cholesteatoma using proliferating cell nuclear antigen

Middle ear cholesteatoma has a remarkable invasive activity accompanied by destruction of ossicles and temporal bone. Its aggressive growth and high tendency to recur have impact on the postoperative care of the patients. Proliferating cell nuclear antigen (PCNA) is a 36 KDa DNA-delta-polymerase-associated protein whose level of synthesis has been found to correlate directly with rates of cellular proliferation. In this present study, we used ABC (avidin-biotin complex) technique and monoclonal antibody to PCNA to evaluate the expression of PCNA in 37 cases of cholesteatoma epithelium and 21 cases of normal postauricular skin. The rate of PCNA-positive cells in basal, parabasal, and upper layer of cholesteatoma epithelium tissue is 78% (29 cases), 68% (25 cases), and 41% (15 cases). In each layer of the postauricular skin tissue is 71% (15 cases), 67% (14 cases) and 34% (7 cases). No statistical difference of expression of PCNA-positive cells exists between each layer of cholesteatoma epithelium and normal postauricular skin; however, a tendency of higher PCNA-positive cells in cholesteatoma epithelium was observed. Immunohistochemical method of PCNA has the advantages of spatial architecture preservation, the relative simplicity of the methodology and the rapid acquisition of results. Although the etiology and histopathology of the growth pattern and osteolytic activity of cholesteatoma are unclear, information on cell kinetics may assist in cholesteatoma classification and may help predict the risk of recurrence and bone destruction. The results of this report indicate that cholesteatoma has a similar proliferative activity to the normal postauricular skin, and cholesteatoma itself is not a real tumor, despite its clinical behavior, which is similar to neoplastic cells. It is necessary to further study whether the cell kinetic information we obtained from the PCNA immunohistochemical analysis provides a valuable tool in accessing the prognosis of the cholesteatoma.

Laparoscopic appendectomy for ruptured appendicitis

We conducted a retrospective analysis to assess the feasibility of laparoscopic appendectomy in cases of ruptured appendicitis. Between August 1993 and April 1998, a total of 328 laparoscopic appendectomies were performed in Min-Shen General Hospital. There were 34 cases of pathology-proven ruptured appendicitis. Patients were divided into three groups according to the operative findings: group 1 (10 cases) consisted of patients with a perforated appendix with local peritonitis, group 2 (15 cases) consisted of patients with perforated appendix with diffused peritonitis, and group 3 (9 cases) consisted of patients with abscess formation around the perforated appendix. Three cases in group 3 were converted to laparotomy and were excluded from this study. Mean age (+/- SD) was 30 +/- 15 years in group 1, 39 +/- 23 years in group 2, and 37 +/- 13 years in group 3. Duration of symptoms was longer in group 3 (4.2 +/-1.2 days) than in group 1 (1.8 +/- 1.3 days) and group 2 (2.3 +/- 1.2 days). There was no difference in operation time among groups 1 (52 +/- 10 min), 2 (64 +/- 13 min), and 3 (67 +/- 16 min). The time of flatus passage after operation was similar in the three groups (group 1, 17 +/- 11 hours; group 2, 21 +/- 12 hours; group 3, 24 +/- 8 hours). Hospital stay was significantly shorter in group 1 (3.0 +/- 1.1 days) than in group 2 (5.1 +/- 2.2 days) and group 3 (4.2 +/- 1.2 days). There were no complications and no readmissions. Our results indicate that the laparoscopic approach is feasible for ruptured appendicitis with local or diffuse peritonitis and in selected cases with abscess formation. However, prospective randomized controlled trials are needed to determine which procedure is to be recommended.

Site-directed mutagenesis of Asp313, Glu315, and Asp391 residues in chitinase of Aeromonas caviae

Site-directed mutagenesis was used to explore the roles of amino acid residues involved in the activity of chitinase from Aeromonas caviae. Kinetic parameters for 4-methylumbelliferyl-N,N'-diacetyl-chitobiose or 4-methylumbelliferyl-N,N',N"-triacetylchitotriose hydrolysis were determined with wild-type and mutant chitinases. Chitinases with the mutations E315D (or Q) and D391E (or N) were severely impaired and had dramatically decreased kcat. However, the effect of the these mutations on the Km values were different. The function of the carboxyl group of Asp313 was partially replaced by the amide of Asn when the 4-methylumbelliferyl-N,N',N"-triacetylchitotriose substrate was used. Results indicated that Asp313, Glu315, and Asp391 might be the best candidates for the catalytic residues of chitinase A from Aeromonas caviae.

Odor memory induces brain activation as measured by functional MRI

PURPOSE

Our goal was to use functional MRI (fMRI) to measure brain activation in response to imagination of odors in humans.

METHOD

fMR brain scans were obtained in 21 normal subjects (9 men, 12 women) using multislice FLASH MRI in response to imagination of odors of banana and peppermint and to the actual smells of the corresponding odors of amyl acetate and menthone, respectively, in three coronal sections selected from anterior to posterior temporal brain regions. Similar studies were obtained in two patients with hyposmia using FLASH MRI and in one patient with hyposmia using echo planar imaging, both before and after theophylline treatment, which returned smell function to or toward normal in each patient. Activation images were derived using correlation analysis, and ratios of areas of brain activated to total brain areas were calculated.

RESULTS

Activation was present in each section in all normal subjects and in each patient after imagination of each vapor. In normal subjects, brain activation in response to imagination of odors was significantly less than that in response to the actual smell of these odors, and activation following imagination of banana odor was significantly greater in men than in women, as was previously reported for the actual smell of the odor of amyl acetate. However, in relative terms, albeit at an absolute lower brain activation level, the ratio of brain activation by imagination of banana to activation by actual amyl acetate odor was about twice as high in women as in men. Before treatment, in patients with hyposmia, brain activation in response to odor imagination was greater than after presentation of the actual odor itself. After treatment, in patients with hyposmia in whom smell acuity returned to or toward normal, brain activation in response to odor imagination was not significantly different quantitatively from that before treatment; however, brain activation in response to the actual odor was significantly greater than that in response to imagination of the corresponding odor. Brain regions activated by both odor imagination and actual corresponding odor were similar and consistent with regions previously described as responding to odors.

CONCLUSION

These studies indicate that (a) odors can be imagined and similar brain regions are activated by both imagined and corresponding actual odors; (b) imagination of odors elicits quantitatively less brain activation than do actual smells of corresponding odors in normal subjects; (c) absolute brain activation in men by odor imagination is greater than in women for some odors, but on a relative basis, the ratio for odor imagination to actual smell in women is twice that in men; (d) odor imagination, once the odor has been experienced, is present, recallable, and capable of inducing a relatively constant degree of brain activation even in the absence of the ability to recognize an actual corresponding odor.

Taste memory induces brain activation as revealed by functional MRI

PURPOSE

Our goal was to use functional MRI (fMRI) to measure brain activation in response to imagination of tastes in humans.

METHOD

fMR brain scans were obtained in 31 subjects (12 men, 19 women) using multislice FLASH MRI and echo planar imaging (EPI) in response to imagination of tastes of salt and sweet in coronal sections selected from anterior to posterior temporal brain regions. Activation images were derived using correlation analysis, and ratios of areas of brain activated to total brain areas were calculated. Total activated pixel counts were used to quantitate regional brain activation.

RESULTS

Activation was present in each section in all subjects after imagination of each tastant. Activation was similar in response to imagination of either salt or sweet and was quantitatively similar to that previously reported in response to imagination of odors of banana and peppermint. Activation was similar in both men and women as opposed to previous results of odor memory in which activation in men was greater than in women. However, subjective responses of intensity of imagined tastes were significantly greater than those previously obtained for odor memory and were consistently, albeit not significantly, greater in women than in men, similar to results previously reported for odor memory. Brain regions activated in response to taste imagination were consistent with regions previously described as involved with actual taste perception in both humans and animals. Regional brain localization for salt and sweet memories could not be differentiated.

CONCLUSION

These studies indicate that (a) tastes can be imagined, (b) brain regions activated for taste imagination are consistent with regions previously described for actual taste perception, and (c) similar to odor memory for banana and menthone, regional brain localization for salt or sweet taste memories could not be differentiated.

Prehospital delay and emergency department management of ischemic stroke patients in Taiwan, R.O.C

OBJECTIVE

To determine the magnitude of prehospital delay and how much time elapses between emergency department (ED) presentation and ED clinical investigations in ischemic stroke patients. Factors associated with prehospital delay were also correlated with demographic characteristics and clinical variables.

METHODS

A prospective, observational study was conducted simultaneously in five community teaching hospitals in Taiwan from October 1997 to April 1998. Included were all patients presenting with acute ischemic stroke. In each case, diagnosis was confirmed by cranial CT scanning. The main outcomes measured were the number of patients presenting at the ED more than two hours after the onset of symptoms (T(prehospital) > 2 hr) and the time spent at the ED for ED physician evaluation, cranial CT scanning, laboratory examinations, and neurologic consultation. Chi-square testing was used to compare the characteristics of patients with T(prehospital) > 2 hr and those with T(prehospital)< or = 2 hr. Independent predictors of T(prehospital) > 2 hr were determined using multiple logistic regression.

RESULTS

Of 157 patients observed, 105 (67%) arrived at the hospital more than 2 hr after the onset of symptoms. Average time from ED presentation to examination by ED physician, completion of CT scanning, and laboratory investigations was 3, 58, and 61 minutes, respectively. Mean time from ED presentation to neurologic consultation was 174 minutes for 38 patients [24%, (38/157)]. The factor associated with T(prehospital) > 2 hr was interhospital transfer (p < 0.05).

CONCLUSION

This study reveals that delayed management of stroke patients is mainly due to delayed ED presentation and to difficulties in obtaining neurologic consultation. Ideally, a stroke center may be incorporated within the EMS system to overcome delays due to interhospital transfer and to difficulties in obtaining neurologic consultation.

Small bowel perforation caused by a sharp bone: laparoscopic diagnosis and treatment

Small bowel perforation caused by sharp or pointed foreign bodies rarely is diagnosed preoperatively because clinical symptoms usually are nonspecific and can mimic other surgical conditions such as appendicitis and cecal diverticulitis. We report the case of a 57-year-old man who underwent diagnostic laparoscopy for abdominal pain of unknown etiology. Swelling and erythema were noted in a segment of small bowel in the right lower abdomen. A tiny sharp-pointed object was found penetrating the inflamed portion of the bowel. This foreign body was removed and the perforation immediately repaired under laparoscopic guidance. The postoperative course was uneventful. We believe that in cases of lower abdominal pain with peritoneal irritation, laparoscopy can provide not only a wide field of examination to localize intraabdominal pathology, but in some instances it can aid in case management.

Effects of diabetes on nitric oxide synthase and growth factor genes and protein expression in an animal model

Erectile dysfunction occurs frequently in humans with diabetes mellitus; the molecular basis of this phenomenon is not known. We investigated the effects of diabetes on penile erection, nitric oxide synthase and growth factors expression in an animal model. Forty male rats were divided into two groups: the experimental group (n = 30) received intraperitoneal injection of Streptozotocin (STZ) dissolved in citrate buffer to induce diabetes; ten age-matched control rats received injection of citrate buffer vehicle only. Before euthanization at eight weeks, erectile function was assessed by electrostimulation of the cavernous nerves. NADPH diaphorase staining was used to identify NOS and immunostaining technique was used to identify nNOS in the penile nerve fibers. RT-PCR was used to identify mRNA expression of nNOS, eNOS, iNOS, ER-beta, ER-alpha, NGF, IGF-I, TGF-beta 1, and AR. Western blot was used to identify nNOS, IGF-I, NGF, and TFG-beta protein expressions. In the diabetic group, there was: (1) a significant decrease in NOS containing nerve fibers in the dorsal and intracavernosal nerves; (2) a significant lower maximal intracavernosal pressure. RT-PCR showed down-regulation of nNOS (large form), iNOS and ER-beta mRNA expression, Immunoblot showed down-regulation of nNOS protein expression and nNOS immunostaining showed less positive staining in the dorsal and intracavernous nerves in the diabetic group. These molecular changes may provide the basis for further studies to explore the association between diabetes and impotence.

Prevention of hypotension after spinal anesthesia for cesarean section: dextran 40 versus lactated Ringer's solution

BACKGROUND

This study was designed to compare the efficacy of 10% dextran 40 with lactated Ringer's (LR) solution in reducing the incidence and severity of hypotension after spinal anesthesia for Cesarean section.

METHODS

Sixty ASA grade I patients scheduled for Cesarean section were randomized into two groups in a double-blind fashion to receive either 500 ml of dextran 40 or 1000 ml of LR solution prior to induction of spinal anesthesia.

RESULTS

The incidence of hypotension was 16 in 30 (53.3%) in the LR solution group and 8 in 30 (26.7%) in the dextran group (P < 0.05). The required dose of ephedrine for treatment of hypotension was significantly greater in the LR solution group than in the dextran group (15.5 mg versus 3.2 mg, P < 0.05). Neonatal outcome, as determined by Apgar score, was good and similar in both groups.

CONCLUSIONS

We concluded that 500 ml of dextran 40 is more effective than 1000 ml of lactated Ringer's solution in reducing the incidence of hypotension induced by spinal anesthesia.

A memory-based self-generated basis function neural network

The paper presents a novel memory-based Self-Generated Basis Function Neural Network (SGBFN) that is composed of small CMACs. The SGBFN requires much smaller memory space than the conventional CMAC and has an excellent learning convergence property compared to multilayer neural networks. Each CMAC in the new structure takes a subset of problem inputs as its inputs. Several CMACs that have different subsets of inputs form a submodule and a group of submodules form a neural network. The output of a submodule is the product of its CMACs' outputs. Each submodule implements a self-generated basis function, which is developed during the learning. The output of the neural network is the sum of the outputs from the submodules. Using only a subset of inputs in each CMAC significantly reduces the required memory space in high-dimensional modeling. With the same size of memory, the new structure is able to achieve a much smaller learning error compared to the conventional CMAC.

Differential regulation of human T-plastin gene in leukocytes and non-leukocytes: identification of the promoter, enhancer, and CpG island

Plastins (fimbrins) are a family of actin-bundling proteins conserved from yeast to humans. In humans, three tissue-specific plastin isoforms have been identified. The T isoform (T-plastin) is unique in that it is expressed in all tissues except leukocytes. To investigate how the T-plastin gene is differentially regulated in leukocytes and non-leukocytes, we isolated a genomic clone that included 9 kb of the upstream flanking region, 0.1 kb of the first exon, and 5.9 kb of the first intron. From this clone, we obtained a continuous sequence of 5535 bp, including 3138 bp of the upstream flanking region, the first exon, and 2286 bp of the first intron. A cluster of four transcription initiation sites was located by S1 mapping. A region spanning these sites and extending 1.4 kb into the first intron had the characteristics of a CpG island. Three CG-containing restriction sites within this island were analyzed and found all or variably methylated in four T-plastin-negative leukemia cell lines. In contrast, the same sites were not methylated in three T-plastin-expressing cell lines or in a sample of normal blood lymphocytes. A basal promoter was located 250 bp upstream from the transciption initiation sites. It comprised a CCAAT box, an Sp1 motif, and four AP2 motifs. No TATA or Inr sequence was found. The basal promoter exhibited weak activity when assayed in fibrosarcoma cells. Stronger promoter activities were found in the presence of the SV40 enhancer or a T-plastin enhancer located some 500 bp from the basal promoter. In T-plastin-negative leukemia cells, the T-plastin basal promoter could be activated by the SV40 enhancer but not by the T-plastin enhancer. DNA footprinting identified the T-plastin enhancer as two inverted symmetric octamers (AGATAACCTC and GAGGTCAGCT) separated by 17 nucleotides.

Analysis of neuronal nitric oxide synthase isoform expression and identification of human nNOS-mu

The neuronal form of nitric oxide synthase (nNOS) is responsible for the production of NO, which acts as a neurotransmitter for penile erection and urethra relaxation. An nNOS splice variant form, nNOS-mu, was first reported to be specifically expressed in skeletal muscle and heart in the rat, but later also identified in rat penile cavernosum. We report here an apparently universal expression of nNOS-mu mRNA in rat tissues, including brain, which was previously reported to be lacking nNOS-mu. Immunoblot analysis revealed that some commercially available nNOS antibodies had high levels of nonspecific activities, which could lead to the appearance of seemingly multiple forms of nNOS. Immunohistochemical analysis with these antibodies also produced nonspecific stainings. In humans, nNOS-mu; expression appeared to be confined to skeletal muscle and heart. Human penile tissues obtained from patients with erectile dysfunction did not express nNOS-mu. The human nNOS-mu-specific cDNA sequence was 89% homologous to its rat counterpart.

The effects of irbesartan added to hydrochlorothiazide for the treatment of hypertension in patients non-responsive to hydrochlorothiazide alone

AIM

To evaluate the antihypertensive efficacy and safety of adding irbesartan to hydrochloride (HCTZ) in patients not adequately controlled by HCTZ alone.

PATIENTS AND METHODS

In this multicenter study, after a single-blind, placebo lead-in period, hypertensive patients received single-blind HCTZ 25 mg once daily. After 4 weeks, 238 patients with seated diastolic blood pressure of 93-110 mmHg continued on HCTZ 25 mg once daily and were randomized to double-blind irbesartan 75 mg once daily or matching placebo for 12 weeks. At week 6, the dosage of irbesartan or placebo was doubled for seated diastolic blood pressure > or = 90 mmHg.

RESULTS

At weeks 2, 6, and 12, irbesartan/HCTZ resulted in significantly greater (P<0.01) reductions from baseline in trough seated diastolic and systolic blood pressure compared with placebo/HCTZ. At week 12, the mean reductions in trough seated diastolic and systolic blood pressure were 7.2 mmHg (95%, C.I., 5.1-9.3 mmHg) and 11.1 mmHg (95% C.I., 7.9-14.3 mmHg) greater, respectively, with irbesartan/HCTZ compared with placebo/HCTZ. At week 12, significantly (P < 0.01) more patients were normalized (trough seated diastolic blood pressure < 90 mmHg) with irbesartan/HCTZ (67%) compared with placebo/HCTZ (29%). The frequency of adverse events, serious adverse events, and discontinuations attributed to adverse events was similar in both groups, and there were no clinically relevant changes in serum creatinine, potassium, or any other laboratory parameter.

CONCLUSION

Irbesartan was effective and well tolerated when added to a background of HCTZ 25 mg in patients whose blood pressure was not adequately controlled by HCTZ alone.

Left ventricular filling profiles and angiotensin system activity in elite baseball players

Left ventricular (LV) filling profiles in elite baseball players has not been reported in the literature. Also, angiotensin system activity in athletes has never been reported. We used echocardiography to compare 20 male elite baseball players (aged 21.9+/-1.0 years) with those of age- and sex-matched healthy sedentary subjects. Compared with the normal group, the athlete group showed a significant increase in LV mass, LV diastolic and systolic dimension, and left atrial dimension (P<0.05, <0.001, <0.001, and <0.001, respectively). No differences in relative wall thickness or fractional shortening were found between these two groups. Diastolic filling profiles, including peak early diastolic filling velocity (E), peak late diastolic filling velocity (A), E:A ratio, early time-velocity integral (Ei), atrial time-velocity integral (Ai), Ei:Ai ratio, early filling time, deceleration time of early filling, and isovolumic relaxation time, were similar in both groups. Angiotensin system activity, including plasma renin activity, plasma aldosterone, and 24-h urinary aldosterone excretion, showed no difference between these two groups.

CONCLUSION

This study suggests that normal LV filling profile, which is mediated partly by normal angiotensin system activity, is not related to increase in LV dimension and mass in elite baseball players.

Analysis and mapping of plastin phosphorylation

Plastins (fimbrins) are a family of three tissue-specific actin-binding proteins. Both L- and T-plastin have been shown to be involved in cytoskeletal reorganization in signal-transduction pathways. Phosphorylation of the leukocyte-specific L-plastin plays important roles in regulating L-plastin function and leukocyte activation. We created L-plastin mutants, changing each of the Ser-5 and Ser-7 residues to alanine. Expression of either mutant in WI38VA13 fibroblasts did not result in phosphorylation. The transfected wildtype L-plastin was phosphorylated in WI38VA13, but its two-dimensional gel pattern suggested that it was phosphorylated on one residue, whereas the endogenous L-plastin in leukocytes was likely phosphorylated on two residues. The nonleukocyte-specific T-plastin, which has an equivalent Ser-7 residue, was not phosphorylated in T-plastin-expressing fibroblasts or in transfected leukocytes. Expression of CK-IIalpha, the catalytic subunit of casein kinase II, resulted in changes of the protein expression profile in leukocytes but not the phosphorylation status of L- or T-plastin. Phorbol myristate acetate induced L-plastin phosphorylation in both leukocytes and fibroblasts, lending support to the view that protein kinase C is the likely candidate kinase for L-plastin phosphorylation.

Lecithin can be detected by volume-selected proton MR spectroscopy using a 1.5 T whole body scanner: a potentially non-invasive method for the prenatal assessment of fetal lung maturity

The prenatal determination of fetal lung maturity is currently assessed by chemical analysis of surfactant associated lipids from aminotic fluid obtained by amniocentesis. This is an invasive procedure with rare but occasionally serious morbidity. Magnetic resonance spectroscopy (MRS) is a non-invasive method for the in vivo localization and identification of molecules with known resonance peaks at specified chemical shifts. In this report we examine the in vitro MRS of a lecithin/saline solution as well as term and preterm amniotic fluid samples with the use of a 1.5 T whole body scanner and a flexible surface coil. We found that amniotic fluid at term demonstrates a resonance peak at 3.2 ppm which was the same as the chemical shift of lecithin in saline. The lecithin peak is not observed in preterm amniotic fluid. This demonstrates the feasibility of using MRS with a whole body scanner to detect lecithin, one of the markers for fetal lung maturity.

Preoperative evaluation and postoperative prediction of hemostatic function with thromboelastography in patients undergoing redo cardiac surgery

BACKGROUND

Patients who receive cardiac procedures, in particular "redo" ones, often suffer complications from massive bleeding, largely due to bypass-induced coagulopathies. Cardiopulmonary bypass (CPB) may cause damage of the blood components, both in terms of quality and quantity. In order to investigate the qualitative changes of blood constituents with special regard to coagulation resulting from the complex insult of previous cardiac surgery, thromboelastography (TEG) was used to analyze the whole clotting process.

METHODS

Seventy-four patients who underwent cardiac surgery with CPB were prospectively studied. Of them, 32 patients received "redo" cardiac surgery. Blood samples for routine laboratory coagulation tests (RCT) and TEG examination were drawn before and after cardiopulmonary bypass. Clinically significant bleeding was defined if the chest tube drainage was greater than 100 ml/h for 3 consecutive h or greater than 300 ml in 1 h during the first 8 h after surgery. Prebypass and postbypass coagulation parameters were compared and the percentage of accuracy, false positive and false negative rate were deduced from calculation.

RESULTS

In the TEG tracings, preoperative alpha angle and maximum amplitude were significantly decreased in the "redo" group when compared with primary group, indicating less competent platelet function and platelet-fibrin interaction. Lower platelet count was also found by conventional coagulation tests in "redo" patients. Postoperatively, higher percentage of excessive hemorrhage was also noted in the "redo" group (42.8% vs. 27.5% in primary group). However, a much lower predictive accuracy was found in "redo" patients in comparison with primary cardiac patients (53.5% vs. 90%).

CONCLUSIONS

We concluded that thromboelastography failed to predict postoperative hemorrhage in "redo" cardiac patients and the graphic recordings derived could not be treated as a guide of transfusion therapy. We thought that inferior preoperative hemostatic status and severer coagulopathy might be responsible for the differences between "redo" and primary cardiac patients.

A method to reduce response times in prehospital care: the motorcycle experience

This study compared the response times of a motorcycle and a standard ambulance in a congested urban emergency medical services (EMS) setting. The study was performed in Taipei, Taiwan, a densely populated urban area. A basic life support (BLS) motorcycle (without defibrillation capability) and an advanced life support (ALS) ambulance were based at three study hospitals and simultaneously dispatched when there was a perceived need for ALS ambulance transport. Over a 3-month period, prehospital personnel evaluated 307 medical and trauma emergencies. Time data were insufficient for analysis in 33 cases, leaving a study population of 274. Response times of the motorcycle and the ambulance were prospectively assessed and compared. During rush hours, the response times of the motorcycle and ambulance were 4.9+/-3.0 minutes and 6.3+/-3.4 minutes (P < .05), respectively, and in non-rush hours, 4.2+/-2.1 minutes and 5.1+/-2.5 minutes (P < .05), respectively. Using motorcycles to transport EMTs to the emergency scene significantly reduced response time compared with a standard ambulance in a congested urban setting. Large prospective studies are required to determine the impact on patient outcome of shorter EMS response times using motorcycles. EMS motorcycles appear feasible and deserve consideration to help expedite prehospital care in other systems in densely populated cities.

Increased brain activation in response to odors in patients with hyposmia after theophylline treatment demonstrated by fMRI

PURPOSE

Our goal was to demonstrate that medical therapy in patients with smell loss (hyposmia) that restored olfactory function toward or to normal could be verified and quantitated by functional MRI (fMRI) of brain and that visual representation of these changes could be used to identify these patients.

METHOD

Multislice FLASH MR or echo planar MR brain scans were obtained in four patients with hyposmia in response to three olfactory stimuli both before and after treatment with theophylline. Activation images were derived using correlation analysis, and ratios of brain area activated to total brain area were obtained.

RESULTS

Prior to treatment, all patients stated that they could not smell; these losses were confirmed by standard psychophysical tests. At this time, fMRI brain activation in response to odors was significantly less than that measured in normal volunteers and similar to activation measured previously in other patients with a similar type of hyposmia. After treatment, subjective smell function improved in three patients and no improvement occurred in one; results were confirmed by psychophysical tests. In each patient in whom smell acuity improved, brain activation in response to each odor increased in each section and mean activation increased significantly for each odor. Activation increased in all regions previously associated with olfactory stimulation and was particularly apparent in orbitofrontal cortex, frontal lobe component of cingulate gyri, temporal lobe gyri, and hippocampus. There also was consistent activation in superior, middle, and inferior frontal lobe gyri. There were no changes in brain activation after treatment in the patient in whom smell did not improve.

CONCLUSION

These results demonstrate that theophylline is an effective therapeutic agent to correct hyposmia in some patients with smell loss. These changes have been documented by fMRI brain scans using olfactory stimuli. This is the first study in which this type of objective improvement following medical treatment has been demonstrated in patients with hyposmia.

Assessment of left ventricular diastolic function after single lung transplantation in patients with severe pulmonary hypertension

OBJECTIVES

This study was designed to observe left ventricular filling by Doppler echocardiography before and after single lung transplantation in patients with severe pulmonary hypertension.

BACKGROUND

Right ventricular pressure overload causes the deformation of the left ventricle by septal flattening toward its cavity, which may result in impaired left ventricular early filling. Recent studies have demonstrated the ability of single lung transplantation to restore right ventricular function in patients with severe pulmonary hypertension. However, changes in left ventricular filling after single lung transplantation have not been well studied.

METHODS

We performed Doppler echocardiography in nine patients with severe pulmonary hypertension before, early (<3 months), and late (>1 year) after single lung transplantation. The study group consisted of eight female patients and one male patient with mean age of 32 years (range, 15 to 48 years). Six patients were diagnosed as having primary pulmonary hypertension and three as having secondary pulmonary hypertension. Nine age-matched normal subjects served as a control group. Doppler measurements included the following: transmitral flow early (E) and atrial (A) velocities, integrals (Ei and Ai), and left ventricular isovolumic relaxation time. The ratio of E/A and atrial filling fraction (Ai/Ei+Ai, AFF) were also determined. Left ventricular geometry was assessed from mid-short axis view with a circular shape factor (CSF).

RESULTS

Early after lung transplantation, the left ventricular geometry became more circular with CSF (mean+/-SD) increasing from 0.63+/-0.09 to 0.88+/-0.05 (p<0.05). However, impaired early filling persisted in the patient group (E/A 0.7+/-0.1 vs preoperative 0.6+/-0.1, AFF 0.61+/-0.1 vs 0.64+/-0.1; both p=not significant). One year later, the left ventricular filling had returned to normal range with E/A 1.4+/-0.6 and AFF 0.35+/-0.1.

CONCLUSIONS

This study observed that the impaired left ventricular early filling persisted shortly after single lung transplantation in patients with severe pulmonary hypertension, despite findings that left ventricular geometry was restored earlier after reversal of pulmonary hypertension. The abnormal filling pattern appeared to be resolved 1 year later. The findings suggest the impaired early filling may be caused by intrinsic left ventricular abnormalities other than ventricular interaction in these patients.

Clinical manifestations and prognostic features of acute methamphetamine intoxication

The prevalence of amphetamine abuse and the frequency of emergency department visits for amphetamine intoxication have increased dramatically worldwide. In this study, we retrospectively investigated the relationship between the prognostic features and clinical manifestations among patients admitted to the emergency department of a university hospital for acute methamphetamine intoxication during a 6-year period. Data collected included gender, age, route of abuse, time between drug exposure and arrival at the emergency department, estimated dose, signs and symptoms, laboratory values, and complications. Emergency therapy and cooling procedures were also recorded. After excluding 26 patients with multiple-drug intoxication, 18 patients (male-to-female ratio, 11:7) were include in the analysis. The mean age was 25.6 years. Thirteen patients survived and five died. Patients who died often presented with coma (80% vs 0%, p = 0.002), shock (60% vs 8%, p = 0.044), convulsions (100% vs 23%, p = 0.007), oliguria (80% vs 0%, p = 0.002), and high body temperature (41.4 +/- 0.5 degrees C vs 39.4 +/- 2.1 degrees C, p = 0.005). Furthermore, patients who died had significantly higher concentrations of blood urea nitrogen (8.7 +/- 2.1 vs 5.6 +/- 2.0 mmol/L, p = 0.01) and serum creatinine (212 +/- 71 vs 115 +/- 27 mumol/L, p = 0.033), and lower values of arterial pH (7.12 +/- 0.12 vs 7.34 +/- 0.10, p = 0.03), than those who survived. In the fatality group, the most common complication was rhabdomyolysis with acute renal failure (5 of 5); multiple organ failure resembling that from heatstroke was the leading cause of death from acute methamphetamine intoxication. In conclusion, the adverse prognostic features in patients with acute methamphetamine intoxication include coma, shock, convulsion, oliguria, and high core temperature. Acidosis, volume depletion, and ischemic renal damage were potential risk factors for development of acute renal failure in these patients.

Aeromonas hydrophila sepsis presenting as meningitis and necrotizing fasciitis in a man with alcoholic liver cirrhosis

Aeromonas hydrophila is rarely reported as a causative organism of meningitis in humans. A 39-year-old man with alcoholic liver cirrhosis was admitted with a 2-day history of fever, chills, and confusion. Laboratory data revealed leukocytosis with granulocytosis, marked impairment of renal and liver function, and an elevated serum ammonia level. A. hydrophila was isolated from both blood and cerebrospinal fluid samples. Skin and soft-tissue lesions, consisting of bullae and necrotizing fasciitis, were found in the lower left leg 2 days after admission. Cultures of the bullous fluid, subcutaneous tissue, and fascia all yielded A. hydrophila. Pathologic examination revealed extensive necrosis. Although the patient was appropriately managed with antibiotics, debridement, and fasciotomies, his clinical status rapidly deteriorated, resulting in death 3 days after admission.

Morphodynamics and pathology of blood vessels III--comparative morphologic study of contraction of smooth muscle cells of hollow viscera and its application to vasoconstriction and vasospasm

The morphologic changes in the walls of hollow viscera caused by contraction and relaxation of smooth muscle cells were studied from autopsy and surgical specimens. The specimens studied included: esophageal spasm (corkscrew and nutcracker esophagus), contraction of the lower esophageal sphincter with marked esophageal dilatation, gaseous distension of the stomach, contraction of the gastric pylorus, bladder and anal sphincter, physiological segmental constriction of the small and large intestines, constriction and distension of the gallbladder, urinary bladder and bronchi, and postpartum contraction of the uterus. In contrast to distension, the constriction of hollow viscera shows marked reduction of the external circumference and diameter with thickening of the wall, contraction of smooth muscle cells, thickening of muscle bundles, remodeling of wall structure, and narrowing or obliteration of the lumen. Morphologic evidence of contraction of smooth muscle cells is demonstrated by varying degrees of typical lengthwise shortening of the cells and squeezing and folding of the nuclei depending on the degree of cytoplasmic contraction of the smooth muscle cells. Using these same classic morphologic signs, we have attempted to study constriction and distension of arteries and arterioles. We can demonstrate contraction of smooth muscle cells and remodeling of arterial and arteriolar walls in patients with spastic coronary artery thrombosis, cocaine-induced coronary artery thrombosis, acute constriction of mesenteric arteries with lacerations of arterial wall, and dissecting hemorrhages induced by large doses of intravenous infusion of vasoconstrictors for hemorrhagic shock, and in patients with sustained, accelerated, or malignant hypertension.