Patients with recognized psychiatric disorders in trauma surgery: incidence, inpatient length of stay, and cost

BACKGROUND

Although psychiatric disturbances are highly prevalent among traumatically injured inpatients, few investigations have assessed the impact of these disorders on surgical length of stay (LOS) and cost.

METHODS

The authors identified all trauma-registry recorded psychiatric diagnoses among patients admitted to University of California Davis Medical Center between January 1993 and December 1996. Linear and logistic regressions were used to assess the unique effects of psychiatric diagnoses on inpatient LOS and cost.

RESULTS

A total of 29% of patients had one or more registry-recorded psychiatric diagnosis. Patients with alcohol abuse diagnoses demonstrated 10% to 12% decreases in LOS and cost (p < 0.01), whereas patients with stress disorders, delirium, and psychoses demonstrated 46% to 103% increases in LOS and cost (p < 0.01).

CONCLUSION

Patients with recognized psychiatric disorders uniquely impact inpatient trauma surgery LOS and cost. Additional investigations of the processes and outcomes of care could lead to cost-effective performance improvement efforts that target the amelioration of comorbid psychiatric disorders among physically injured trauma survivors.

Enhanced detection of left atrial spontaneous echo contrast by transthoracic harmonic imaging in mitral stenosis

BACKGROUND

Spontaneous echo contrast (SEC) of the left atrium is associated with increased risk of thromboembolism in patients with mitral stenosis (MS). The determination of the presence and severity of left atrial (LA) SEC is of prognostic importance in these patients. Harmonic imaging (HI), a novel echocardiographic technique that differs from conventional fundamental imaging (FI) in that it involves transmitting ultrasound at one frequency and receiving at twice the transmitted frequency, produces better endocardial border definition and myocardial opacification. However, there are no data about its value for the detection of LA SEC. The purpose of this study was to investigate the utility of transthoracic noncontrast tissue HI in the detection of LA SEC in patients with MS.

METHODS

Seventy-four consecutive patients with MS (49 women, mean age 51 years) underwent standard transthoracic echocardiography (TTE) in both HI and FI modes and transesophageal echocardiography (TEE) to determine the presence and severity of LA SEC. Left atrial SEC was graded by TEE as either mild (only seen at high gain) or severe (visible in the entire left atrium at normal gain control of the equipment). The control group comprised 30 patients randomly selected from patients who did not have LA SEC at the TEE examination.

RESULTS

Atrial fibrillation was found in 46 patients (62.2%). The mean mitral valve area and mean mitral gradient were 1.0+/-0.3 cm(2) and 8.2+/-4.1 mm Hg, respectively. Nine patients (12.2%) had episodes of systemic embolism; 8 had stroke, and 1 had peripheral embolism. Left atrial thrombus was found in 11 patients (14.9%) by TEE. Left atrial SEC was present in all but one patient by TEE (mild in 35 patients, severe in 38). Fundamental imaging with TTE, however, revealed LA SEC in only 5 (6.8%) of the 73 patients. In contrast, with HI, LA SEC could be detected in 63 (86.3%) patients. In the detection of severe LA SEC, the sensitivities of FI and HI were 13.2% (5/38) and 100% (38/38), respectively. Left atrial SEC was not observed in control subjects by either FI or HI.

CONCLUSIONS

Transthoracic HI significantly enhances the detection of LA SEC in patients with MS.

A case of endobronchial aspergilloma

Pulmonary aspergillosis may be classified under three categories, depending upon whether the host is atopic or immunocompromised: invasive aspergillosis, allergic bronchopulmonary aspergillosis (ABPA) or aspergilloma. However, it is not always possible to effectively categorize this disease. We experienced a case of endobronchial aspergilloma, which was difficult to categorize, in a healthy male patient. The chest X-ray and computed tomography showed an ill-defined nodule mimicking lung cancer. Fiberoptic bronchoscopy revealed an aspergilloma without cavity formation in the left lower laterobasal segmental bronchial orifice. The aspergilloma was removed and the patient's symptoms were relieved. We present this unusual case with a review of the literature.

A non-cleavable mutant of Fas ligand does not prevent neutrophilic destruction of islet transplants

BACKGROUND

Fas ligand (FasL) mediates apoptosis of susceptible Fas-expressing lymphocytes, and may contribute to the maintenance of peripheral tolerance. In transplantation models, however, artificial expression of FasL on cellular as well as islet transplants results in accelerated rejection by neutrophils. The mechanism of the neutrophilic response to FasL expression is unknown. FasL, like other members of the tumor necrosis factor family, is cleaved to a soluble form by metalloproteases. We tested the hypothesis that soluble FasL (sFasL) was responsible for neutrophil migration by creating a non-cleavable mutant of FasL.

METHODS

Three mutants of FasL with serial deletions in the putative proteolytic cleavage site of human FasL were made using inverse polymerase chain reaction. The relative fractions of sFasL and membrane-bound FasL were assessed by Western blot and immunoprecipitation, as well as by cytotoxicity assay using Fas-expressing target cells. The fully non-cleavable mutant was transduced into murine islets as well as myoblasts and tumor cell lines, and tested in a murine transplantation model.

RESULTS

Serial deletions in the putative metalloprotease site of FasL resulted in a fully non-cleavable mutant of FasL (ncFasL). Expression of ncFasL in tumor lines induced higher levels of apoptosis in Fas bearing targets than wild-type FasL. Transplantation of ncFasL-expressing islets under the kidney capsule of allogenic mice resulted in accelerated rejection identical to that seen with wild-type Fas ligand-expressing islets. Myoblasts and tumor cell lines expressing ncFasL also induced neutrophil infiltration.

CONCLUSIONS

Membrane-bound Fas ligand is fully capable of inducing a neutrophilic response to transplants, suggesting an activation by Fas ligand of neutrophil chemotactic factors.

Is the left atrial v. wave the determinant of peak pulmonary artery pressure in patients with pure mitral stenosis?

A large left atrial (LA) v. wave can be observed in patients with pure mitral stenosis (MS) because of decreased LA compliance. Few data are available regarding the relation between the magnitude of the LA v wave and pulmonary artery pressure in MS. We hypothesized that pulmonary artery pressure may be higher in patients with decreased LA compliance and thus a large v. wave. We analyzed the right-sided cardiac and transseptal catheterization data in 113 patients (16 men and 97 women, mean age 39 years) with pure rheumatic MS in sinus rhythm. Peak systolic, diastolic, and mean pulmonary artery pressures were measured with right-sided cardiac catheterization. The magnitude of LA a and v. waves were measured through transseptal catheterization. Two-dimensional and Doppler echocardiography were also performed to measure LA size, mitral valve area, mean mitral gradient, and valvular regurgitation. Multiple regression analysis was performed to identify the most important factor in the determination of pulmonary artery pressure. A large v wave, defined if peak v wave height exceeded the mean LA pressure by > or =10 mm Hg, was observed in 43 of 113 patients (38%). Increased pulmonary artery systolic pressure (> or =50 mm Hg) was observed in 38 patients (34%). Univariate analysis showed that the factors associated with increased pulmonary artery systolic pressure were smaller mitral valve area, higher mean mitral gradient, higher mean LA pressure, and higher LA v. wave; among them, LA v wave (p <0. 001) and mean mitral gradient (p<0.001) were significant independent factors for pulmonary artery systolic pressure in multivariate analysis. In conclusion, in patients with pure MS and sinus rhythm, the magnitude of the LA v. wave is strongly associated with pulmonary artery pressure. This finding may suggest that LA compliance is a major contributing factor determining pulmonary artery pressure in pure MS.

A dendritic cell line genetically modified to express CTLA4-IG as a means to prolong islet allograft survival

BACKGROUND

Dendritic cells are potent antigen-presenting cells that bind allogeneic T cells. They are thus candidates for targeting immunoregulatory molecules to the alloreactive T cell compartment and suppressing the alloimmune response.

METHOD

A dendritic cell line derived from the BALB/c mouse (H2d) was genetically modified to express the immunoregulatory molecule CTLA4-Ig. The ability of these dendritic cell transfectants to downregulate the alloimmune response was tested in an islet transplant model. Allogeneic C57Bl/6 (H2b) mice were rendered diabetic with streptozocin, and they received BALB/c islet (H2d) transplants. Mice were administered 25 million untransfected or CTLA4-Ig-transfected D2SC/1 cells i.v. on the day of islet transplantation and 6 days later[fnc].

RESULT

Mice treated with CTLA4-Ig-transfected D2SC/1 cells demonstrated prolonged allograft survival (mean = 20 days, median = 17 days, SD = 9.39) compared with mice treated with untransfected D2SC/1 cells (mean = 12 days, median = 11 days, SD=2.74) or untreated control mice (mean = 11 days, median = 11 days SD = 1.41). Third party allograft survival was not prolonged in mice receiving similar treatment.

CONCLUSIONS

These results demonstrate that a genetically modified dendritic cell line can suppress the alloimmune response and prolong islet allograft survival in an allospecific manner. The findings also suggest that genetically modified dendritic cells may be useful in targeting alloreactive T cells and prolonging allograft survival.

Expression of vascular endothelial growth factor and thrombospondin-1 in colorectal carcinoma

Solid tumors require neovascularization for growth and metastasis. Vascular endothelial growth factor (VEGF) is a well-characterized inducer of angiogenesis, while, thrombospondin-1 (TSP-1) is thought to be an antiangiogenic factor. In this study, we examined the expressions of these antigens and their relationship with microvessel density, and determined their prognostic significance. One hundred specimens resected from patients with colorectal adenocarcinoma were examined using immunohistochemical methods. Microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in tumors that were VEGF-positive and TSP-1-negative than in other tumors. Patients with VEGF-positive tumors had a significantly worse prognosis than did those with VEGF-negative tumors, and TSP-1 expression was inversely correlated with prognosis. The frequency of hepatic recurrence was significantly higher in patients with tumors that were VEGF-positive and TSP-1-negative than in all other patients. In conclusion, VEGF and TSP-1 are important regulators of tumor angiogenesis, and combined analysis of VEGF and TSP-1 may be useful for predicting recurrence in patients with colorectal adenocarcinoma.

Expression of leptin receptor (Ob-R) in human atherosclerotic lesions: potential role in intimal neovascularization

Neovascularization of the adventitial vasa vasorum with extension into the intima of atherosclerotic lesions is frequently observed, but its pathophysiological significance is still subject to debate. Recently, leptin, the product of the Ob gene, was identified. Leptin, via activation of the endothelial receptor (Ob-R), generates a growth signal involving a tyrosine kinase-dependent intracellular pathway and promotes angiogenic processes. We hypothesized that a high concentration of leptin within vasa vasorum and plaque itself, may influence inflammatory and vascular neovascularization coupling with functional upregulation of the vascular endothelial growth factor (VEGF). Microscopic computerized tomography was utilized for the spatial distribution of vasa vasorum and intimal neovascularization from atherosclerotic human coronary arteries. Atherosclerotic coronary arteries showed a dense plexus of microvessels in the adventitia and plaque itself. Microscopic analysis from human atherosclerotic aortas revealed an increase in the intimal thickness with neovascularization. The immunoreactivity for Ob-R, VEGF and matrix metalloproteinase (MMP) increased in atherosclerotic plaque, predominantly in the endothelial lining of the intimal neovessel and macrophages/foam cells. Our observation of a prominent colocalization between Ob-R, VEGF and MMP supports this hypothesis and these factors participate in the neovascularization of atherosclerotic lesions. The present study is the first report on vascular tissue and it opens a promising perspective concerning future investigations of leptin-dependent modulation of atherogenesis and vascular neovascularization under pathophysiolgical conditions.

Coexpression of cyclooxygenase-2 and matrix metalloproteinases in human aortic atherosclerotic lesions

Inflammation appears to have a major role in the development of atherosclerosis. Cyclooxygenase-2 (COX-2) is involved in the inflammatory response via the generation of prostanoids that, in turn, are involved in the production of matrix metalloproteinases (MMPs). This study aimed to investigate atherosclerosis in human aortas for in situ tissue distribution of COX-2, MMPs including MMP-9 and membrane type 1 MMP (MT1-MMP), and tissue inhibitor of metalloproteinase-2 (TIMP-2). Immunohistochemical studies were performed on atherosclerotic lesions of aortas from patients with aortic aneurysms (n = 4) and dissections (n = 3) by using antibodies to COX-2, MMP-9, MT1-MMP, and TIMP-2. Control tissues were obtained from traumatically dissected aortas (n = 2). All specimens from diseased aortas had atherosclerotic lesions ranging from fatty streak to atheromatous plaques. In control, there was no expression of COX-2, MMP-9, and MT1-MMP in all aortic layers. Immunoreactivity for COX-2 was predominantly noted in macrophages and smooth muscle cells (SMCs) of the intima including atherosclerotic plaque itself and the medial layer of the plaque base, as well as in SMCs and endothelial lining of the vasa vasorum in the adventitia. Immunoreactivity for MMP-9 and MT1-MMP was found in the same distribution as that of COX-2. Additionally, the expression of TIMP-2 increased in relation to MMP-9 expression. This study demonstrates that COX-2 is coexpressed with MMP-9 and MT1-MMP, not only by macrophages and SMCs in atherosclerotic lesions, but also in endothelial lining of the vasa vasorum of human aortas. Thus, vascular inflammatory reactions may influence extracellular matrix remodeling by coactivation of MMPs in the development of atherosclerosis and, in turn, the progression of disease.

Subclavian arteritis and pseudoaneurysm formation secondary to stent infection

Technically uncomplicated percutaneous angioplasty and stent placement of a left subclavian artery stenosis was performed in a 56-year-old man for treatment of subclavian steal syndrome and vertebrobasilar insufficiency. Six days later the patient was readmitted with Staphylococcus aureus bacteremia and stigmata of septic emboli isolated to the ipsilateral hand. Nine days later he had computed tomography (CT) evidence of a contrast-enhancing phlegmon surrounding the stent. Despite clinical improvement and resolution of bacteremia on intravenous antibiotic therapy, the phlegmon progressed, and at day 21 a pseudoaneurysm was angiographically confirmed. The patient underwent surgical removal of the stented arterial segment and successful autogenous arterial reconstruction. The possible contributory factors leading to stent infection were prolonged right femoral artery access and an infected left arm venous access. Although the role of prophylactic antibiotics remains to be defined, it may be important in cases where the vascular access sheath remains in place for a prolonged period of time.

Apoptosis in dilated cardiomyopathy

OBJECTIVE

Cardiomyopathy, a popular diagnosis that always obscures more than it reveals, nevertheless has several characteristic histological features. These prominently include widespread focal myocardial fibrosis and associated hypertrophy of surviving cardiac myocyte. In fact, focal noninflammatory degeneration (not necrosis) has been demonstrated as a feature of many forms of cardiac hypertrophy. We hypothesized that this loss of myocardial cells in dilated cardiomyopathy (DCMP) may result from cell death by apoptosis.

METHODS

Endomyocardial biopsy specimens from the right ventricles of six patients who suffered from DCMP were studied, and myocardial specimens from two persons who died in motor vehicle accidents were used as negative controls. For identification of apoptosis, immunohistochemistry with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end-labeling was performed. In addition, apoptosis was confirmed morphologically by confocal laser scanning microscopy with propidium iodide.

RESULTS

Apoptosis, that was represented by an apoptotic index ranging from 19.8 to 25.4%, could be extensively seen in myocytes and also rarely in non-myocytes of interstitium and vascular endothelium. Morphologically, there were a lot of nuclei with clumps of condensed chromatin, suggestive of apoptosis.

CONCLUSION

The present study demonstrated that myocyte loss in DCMP might be mainly due to the apoptosis of myocytes and interstitial cells, rather than inflammation or cell necrosis.

Generalized peritonitis with pneumoperitoneum caused by the spontaneous perforation of pyometra without malignancy: report of a case

Spontaneous perforation is a very rare complication of pyometra. We report herein the case of an 88-year-old woman who presented with muscular rigidity and free air on abdominal X-ray films. Perforation of the gastrointestinal tract was diagnosed preoperatively, and an emergency laparotomy was performed. A total hysterectomy with bilateral salpingo-oophorectomy was carried out under the diagnosis of generalized peritonitis caused by the spontaneous perforation of pyometra. The culture of purulent fluid from the abdominal cavity showed only Escherichia coli, with no anaerobic bacteria. Histological examination revealed pyometra with necrosis of the endometrium and no evidence of malignancy. The patient was discharged on postoperative day 68 without any major complications. Pyometra is an unusual cause of peritonitis, but it must be considered as a possible diagnosis in elderly women presenting with an acute abdomen. Following this case report, we discuss the problems associated with establishing a correct preoperative diagnosis of generalized peritonitis caused by the spontaneous perforation of pyometra.

Vascular endothelial growth factor expression in preoperative biopsy specimens correlates with disease recurrence in patients with early gastric carcinoma

BACKGROUND

Recently many studies have demonstrated that the degree of tumor angiogenesis is related to the aggressiveness of the tumor and clinical outcome. Vascular endothelial growth factor (VEGF) is a well characterized inducer of angiogenesis. In this study, the authors investigated the prognostic significance of VEGF expression in patients with early gastric carcinoma together with p53 gene abnormality and tumor cell proliferation.

METHODS

One hundred ninety-five endoscopically biopsied specimens obtained preoperatively from patients with early gastric carcinoma were studied immunohistochemically.

RESULTS

According to conventional clinicopathologic factors, submucosal invasion, lymph node metastases, and tumor size were associated significantly with the incidence of disease recurrence. According to conventional biologic factors, VEGF expression was observed more frequently in patients with disease recurrence compared with those without disease recurrence whereas neither p53 abnormality nor tumor cell proliferation were correlated with prognosis. Moreover, multivariate analysis indicated that VEGF expression (as well as submucosal invasion and lymph node metastases) is an independent predictor of disease recurrence.

CONCLUSIONS

The results of the current study show that VEGF expression may be a useful prognostic factor for patients with early gastric carcinoma.

Vascular endothelial growth factor expression in preoperative biopsy specimens correlates with disease recurrence in patients with early gastric carcinoma

BACKGROUND

Recently many studies have demonstrated that the degree of tumor angiogenesis is related to the aggressiveness of the tumor and clinical outcome. Vascular endothelial growth factor (VEGF) is a well characterized inducer of angiogenesis. In this study, the authors investigated the prognostic significance of VEGF expression in patients with early gastric carcinoma together with p53 gene abnormality and tumor cell proliferation.

METHODS

One hundred ninety-five endoscopically biopsied specimens obtained preoperatively from patients with early gastric carcinoma were studied immunohistochemically.

RESULTS

According to conventional clinicopathologic factors, submucosal invasion, lymph node metastases, and tumor size were associated significantly with the incidence of disease recurrence. According to conventional biologic factors, VEGF expression was observed more frequently in patients with disease recurrence compared with those without disease recurrence whereas neither p53 abnormality nor tumor cell proliferation were correlated with prognosis. Moreover, multivariate analysis indicated that VEGF expression (as well as submucosal invasion and lymph node metastases) is an independent predictor of disease recurrence.

CONCLUSIONS

The results of the current study show that VEGF expression may be a useful prognostic factor for patients with early gastric carcinoma.

Vascular endothelial growth factor expression in preoperative biopsy specimens correlates with disease recurrence in patients with early gastric carcinoma

BACKGROUND

Recently many studies have demonstrated that the degree of tumor angiogenesis is related to the aggressiveness of the tumor and clinical outcome. Vascular endothelial growth factor (VEGF) is a well characterized inducer of angiogenesis. In this study, the authors investigated the prognostic significance of VEGF expression in patients with early gastric carcinoma together with p53 gene abnormality and tumor cell proliferation.

METHODS

One hundred ninety-five endoscopically biopsied specimens obtained preoperatively from patients with early gastric carcinoma were studied immunohistochemically.

RESULTS

According to conventional clinicopathologic factors, submucosal invasion, lymph node metastases, and tumor size were associated significantly with the incidence of disease recurrence. According to conventional biologic factors, VEGF expression was observed more frequently in patients with disease recurrence compared with those without disease recurrence whereas neither p53 abnormality nor tumor cell proliferation were correlated with prognosis. Moreover, multivariate analysis indicated that VEGF expression (as well as submucosal invasion and lymph node metastases) is an independent predictor of disease recurrence.

CONCLUSIONS

The results of the current study show that VEGF expression may be a useful prognostic factor for patients with early gastric carcinoma.

Invasiveness of Helicobacter pylori into human gastric mucosa

BACKGROUND

Helicobacter pylori has generally been observed only in the gastric mucous layer or in the spaces between gastric mucus-secreting cells and not in the gastric epithelial cells or in the lamina propria. The purpose of this study is to determine whether H. pylori invades the gastric mucosa, using an immunoelectron microscopical examination of human gastric mucosa infected with H. pylori.

MATERIALS AND METHODS

Five hundred gastric antral biopsy specimens were fixed in a periodate-lysin-paraformaldehyde solution, embedded in Lowicryl, sectioned, and examined with a light microscope. One hundred specimens moderately or severely infected with H. pylori were selected and were incubated with polyclonal rabbit anti-H. pylori antibody. The specimens were washed, incubated with 20 nm of colloidal gold-conjugated goat anti-rabbit IgG, stained with uranyl acetate and lead citrate, and observed with a transmission electron microscope.

RESULTS

In one case, a bacterium was observed within the cytoplasm of a gastric mucus-secreting cell; in another case, a few bacteria were observed within the cytoplasm of a stromal cell in the lamina propria. The bacteria could be differentiated from degenerated intracellular organelles by gold particles attached to the bacteria.

CONCLUSION

H. pylori rarely invade the lamina propria and gastric cells.

Identification of a human immunodeficiency virus type 1 that stably uses tRNALys1,2 rather than tRNALys,3 for initiation of reverse transcription

HIV-1 virions contain approximately equal amounts of tRNALys,3 and tRNALys1,2, yet tRNALys,3 has been found to be exclusively used for initiation of reverse transcription. Since previous studies have shown that even if the primer binding site (PBS) was mutated to be complementary to tRNALys1,2, the virus did not stably use tRNALys1,2 to initiate reverse transcription, the virus must have evolved a mechanism for the exclusive use of tRNALys,3 to initiate reverse transcription. To investigate how HIV-1 discriminates tRNALys1,2 from tRNALys,3 for initiation of reverse transcription, two proviral genomes that contain nucleotide changes in U5 and a PBS to be complementary to regions of tRNALys1,2 were constructed. One genome contains 5 [HXB2(L12-AC)] nucleotides while another contains 15 [HXB2(L12-ACgg)] nucleotides in U5 complementary to the anticodon region of tRNALys1,2. Viruses derived from the transfection of the proviral genomes were infectious in SupT1 cells. Analysis of the endogenous reverse transcription reactions from viruses derived from HXB2 (L12-AC) and HXB2 (L12-ACgg) obtained from transfection revealed that both exclusively used tRNALys1,2 to initiate reverse transcription. Following extensive in vitro culture, though, sequence analysis of proviral genomes revealed that while the virus derived from HXB2(L12-AC) stably maintained a PBS complementary to tRNALys1,2, the virus derived from HXB2 (L12-ACgg) had reverted back to contain a PBS complementary to tRNALys,3. RNA modeling of the U5-PBS of the genome from HXB2(L12-AC) supports the conclusion that the fine specificity for discrimination between tRNALys,3 and tRNALys1,2 for use as a primer for HIV-1 reverse transcription resides in the structure of the U5-PBS region of the viral genome.

Genetic analysis of a unique human immunodeficiency virus type 1 (HIV-1) with a primer binding site complementary to tRNAMet supports a role for U5-PBS stem-loop RNA structures in initiation of HIV-1 reverse transcription

Human immunodeficiency virus type 1 (HIV-1) exclusively uses tRNA3Lys to initiate reverse transcription. A novel HIV-1 mutant which stably utilizes tRNAMet rather than tRNA3Lys as a primer was previously identified [HXB2(Met-AC] (S.-M. Kang, Z. Zhang, and C. D. Morrow, J. Virol. 71:207-217, 1997). Comparison of RNA secondary structures of the unique sequence (U5)-primer binding site (PBS) viral RNA genome alone or complexed with tRNAMet of HXB2(Met-AC) revealed structural motifs in common with the U5-PBS of the wild-type virus. In the current study, mutations were constructed to alter the U5-PBS structure and disrupt the U5-PBS-tRNAMet interaction of the virus derived from HXB2(Met-AC). All of the mutant viruses were infectious following transfection and coculture with SupT1 cells. Analysis of the initiation of reverse transcription revealed that some of the mutants were impaired compared to HXB2(Met-AC). The genetic stability of the PBS from each virus was determined following in vitro culture. Two mutant proviral constructs, one predicted to completely disrupt the stem-loop structure in U5 and the other predicted to destabilize contact regions of U5 with tRNAMet, reverted back to contain a PBS complementary to tRNA3Lys. All other mutants maintained a PBS complementary to tRNAMet after in vitro culture, although all contained multiple nucleotide substitutions within the U5-PBS from the starting proviral clones. Most interestingly, a viral mutant containing a 32-nucleotide deletion between nucleotides 142 and 173, encompassing regions in U5 which interact with tRNAMet, maintained a PBS complementary to tRNAMet following in vitro culture. All of the proviral clones recovered from this mutant, however, contained an additional 19-nucleotide insertion in U5. RNA modeling of the U5-PBS from this mutant demonstrated that the additional mutations present in U5 following culture restored RNA structures similar to those modeled from HXB2(Met-AC). These results provide strong genetic evidence that multiple sequence and structural elements in U5 in addition to the PBS are involved in the interaction with the tRNA used for initiation of reverse transcription.

Expression of p53 and vascular endothelial growth factor associated with tumor angiogenesis and prognosis in gastric cancer

Recently, it has been reported that p53 tumor suppressor gene plays an important role in controlling tumor angiogenesis by regulating expression of vascular endothelial growth factor (VEGF), which is a well-characterized angiogenic inducer. In this study, we investigated these antigens' expression together with microvessel density, and investigated their clinical importance. One hundred twenty specimens resected from patients with gastric carcinoma were investigated using immunohistochemical methods. p53 and VEGF expression was observed in 42 and 35% tumors, respectively. p53 and VEGF staining status was coincided in 72% tumors, and a significant correlation was found between p53 and VEGF status. The microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in p53-positive or VEGF-positive tumors. According to prognosis, patients with p53-positive tumors had significantly worse survival than those with p53-negative tumors. There was also a significant worse survival in the patients with VEGF-positive tumors than those with VEGF-negative tumors. Moreover, the 5-year survival rate was lowest in the patients with p53-positive and VEGF-positive tumors, while it was highest in the patients with p53-negative and VEGF-negative tumors. In conclusion, both p53 and VEGF significantly correlated with tumor vascularity and prognosis in patients with gastric carcinoma.

Index of myocardial performance using Doppler-derived parameters in the evaluation of left ventricular function in patients with essential hypertension

We analyzed Doppler echocardiographic data in 120 subjects with normal sinus rhythm; normals (NL, n = 60, ages 54.1 +/- 15.1) and essential hypertensive patients (HT, n = 60, ages 57.3 +/- 10.2). The IMP was calculated as follows: IMP = (ICT + IRT)/ET, ICT; isovolumic contraction time, IRT; isovolumic relaxation time, ET; ejection time. There were no significant differences in ejection fraction (EF), stroke volume index (SVI), cardiac index (CI), ET and ICT between NL and HT. There were, however, significant differences in deceleration time (DT), E/A ratio, IRT and the IMP between the two groups (199.5 +/- 45.6 msec vs 222.3 +/- 54.3 msec, p < 0.01; 1.4 +/- 0.7 vs 0.9 +/- 0.2, p < 0.01; 113.6 +/- 30.2 msec vs 134.2 +/- 29.6 msec, p < 0.01; 0.6 +/- 0.1 vs 0.8 +/- 0.3, p < 0.05). In HT, there were no differences in EF, SVI, CI, E/A ratio and DT between the NYHA I (Gp I, n = 36) and II (Gp II, n = 24) groups. However, ET of Gp II was significantly shorter than that of Gp I (259.4 +/- 43.5 msec vs 297.8 +/- 33.6 msec, p < 0.01). ICT, IRT and the IMP were significantly increased in Gp II, compared to those of Gp I (64.4 +/- 23.9 msec vs 89.4 +/- 46.2 msec, p < 0.05; 120.3 +/- 21.0 msec vs 155.2 +/- 28.5 msec, p < 0.001; 0.6 +/- 0.2 vs 1.0 +/- 0.4, p < 0.001). There were no differences in heart rate and mean blood pressure between Gp I and Gp II (70.9 +/- 11.4/min vs 66.3 +/- 11.4/min, p > 0.05; 138.4 +/- 21.2 mmHg vs 131.3 +/- 19.9 mmHg, p > 0.05). These data suggest that the IMP may be a useful parameter and an early indicator of left ventricular dysfunction in essential hypertensive patients with normal systolic function.

Prediction and limitation of hepatic tumor resection without blood transfusion in cirrhotic patients

BACKGROUND

The need for blood transfusion in cirrhotic liver resection is difficult to determine because of inaccurate estimation of operative blood loss. Moreover, blood transfusion is detrimental to cirrhotic patients.

OBJECTIVE

To investigate the predictors and limitations of hepatectomy without blood transfusion for cirrhotic patients.

DESIGN

Retrospective study.

SETTING

University hospital, a tertiary referral center.

PATIENTS

A consecutive 163 cirrhotic patients underwent resection for liver tumor(s) under a policy of restrictive blood transfusion.

INTERVENTIONS

Estimated blood losses and clinicopathological features of patients who received and those who did not receive a blood transfusion were compared.

MAIN OUTCOME MEASURES

Estimated operative blood losses, preoperative assessments, and operative procedures.

RESULTS

There were 48 patients in the group who received a blood transfusion, with 1275 +/- 650 mL (mean +/- SE) of blood transfused, and 115 patients in the group who did not receive a blood transfusion. From discriminant analysis, the cutoff value of estimated blood loss for blood transfusion was 1685 mL. Tumor size and site of hepatectomy were found to be independent variables influencing blood transfusion under logistic regression analysis.

CONCLUSIONS

Most cirrhotic patients tolerate hepatectomy without blood transfusion when the estimated operative blood loss is less than 1600 mL. Hepatectomy can be performed in cirrhotic patients without blood transfusion if the tumor is small (<5 cm), and/or the resection area is confined to Couinaud segments II, III, and VI. In this study, the largest amount of estimated blood loss in cirrhotic liver resection without blood transfusion was 2350 mL, but the uppermost limit remains to be determined.

Genetic evidence of the interaction between tRNA(Lys,3) and U5 facilitating efficient initiation of reverse transcription by human immunodeficiency virus type 1

Previous studies using in vitro chemical and enzyme methods demonstrated that, in addition to the primer-binding site (PBS), two regions upstream of the PBS in U5 of HIV-1 RNA interact with tRNA(Lys,3) during the initiation of reverse transcription. One region corresponds to nucleotides 167-172 of U5, which are complementary to the anticodon region of tRNA(Lys,3); a second region corresponds to nucleotides 142-145 of U5, which interacts with nucleotides 43-46 of tRNA(Lys,3). To study the importance of these viral RNA-tRNA interactions in reverse transcription and viral replication, we mutated the two corresponding regions in the infectious HIV-1 proviral DNA (HXB2). Changing nucleotides 167-172 from GAAAAU to CCACAA (which is complementary to the anticodon of tRNA(His)) or changing nucleotides 142-144 from CCC to GGG did not affect protein expression or production of virus from transfected proviral DNAs. Analysis of these viruses revealed that, although all were infectious, the initial replication was delayed compared with wild-type virus. Using an endogenous reverse transcription-PCR assay, we found that the initiation of the reverse transcription in the mutant viruses was less efficient than that for the wild-type virus. Analysis of the proviral DNA sequences after 2 months of in vitro culture revealed that most progeny viruses derived from the mutant that contained the CCACAA motif had acquired nucleotide substitutions within and surrounding the CCACAA nucleotides. All the viruses recovered from the mutant that originally contained the GGG nucleotides reverted back to contain the wild-type CCC sequence. The majority of the proviral clones derived from virus containing the double mutations had gained additional mutations within the CCACAA and GGG motifs. The replication of the mutant viruses was now similar to that of the wild type. The results of these studies demonstrate that interactions between the tRNA and U5 are important for generation of an optimized initiation complex required for efficient reverse transcription.

Preferential completion of human immunodeficiency virus type 1 proviruses initiated with tRNA3Lys rather than tRNA1,2Lys

All retroviral genomes contain a nucleotide sequence designated as the primer binding site (PBS) which is complementary to the tRNA used for initiation of reverse transcription. For human immunodeficiency virus type 1 (HIV-1), all naturally occurring genomes have a PBS complementary to tRNA3Lys. However, within HIV-1 virions, there are approximately equal amounts of tRNA1Lys, tRNA2Lys, and tRNA3Lys. We have used an endogenous reverse transcription-PCR technique specific for the tRNA species within isolated HIV-1 virions to demonstrate that in addition to tRNA3Lys, tRNA1Lys and tRNA2Lys could be used for initiation of HIV-1 reverse transcription. Using a single-round infection assay which employed an HIV-1 genome with a gpt gene encoding xanthine-guanine phosphoribosyl transferase in place of the env gene, we generated cell lines resistant to mycophenolic acid. Analysis of the U5-PBS from single-cell clones revealed PBS complementary to tRNA3Lys, not tRNA1Lys or tRNA2Lys. A mutant HIV-1 genome was then created which would favor the completion of reverse transcription with tRNA1,2Lys. Using this provirus in the complementation system, we again found only genomes with a PBS complementary to tRNA3Lys from proviral DNA isolated from gpt-resistant single-cell colonies. Finally, infection of cells with a mutant HIV genome with a PBS complementary to tRNA1,2Lys resulted in gpt- resistant cell colonies which contained integrated provirions with a PBS complementary to tRNA1,2Lys. The results of these studies suggest that the selection of tRNA3Lys for initiation of HIV-1 reverse transcription occurs both at the initiation and at a postinitiation step in reverse transcription prior to integration of the proviral DNA.

Genetic analysis of the U5-PBS of a novel HIV-1 reveals multiple interactions between the tRNA and RNA genome required for initiation of reverse transcription

A novel HIV-1 genome that stably utilizes tRNA(His) rather than tRNA(Lys,3) to initiate reverse transcription was used to study features for the interaction between the tRNA and viral RNA genome. In addition to a primer binding site (PBS) complementary to tRNA(His), this virus contains a six-nucleotide sequence in U5 complementary to the anticodon-loop of tRNA(His) and three additional substitutions: U174-to-G, G181-to-A, and U200-to-C [HXB2(His-AC-GAC)]. Mutations in these three nucleotides resulted in viruses with three different genotypes: one group maintained a PBS complementary to tRNA(His) with restored G174A181C200 or G174A181U200 configurations, one group reverted to a PBS complementary to tRNA(Lys,3), and one group contained two or more PBSs complementary to different tRNAs on the same viral genome. Characterization of a previously identified virus with additional C152-to-A and C160-to-U substitutions [HXB2(His-AC-A152U160-GAC)] revealed that this virus maintained a PBS complementary to tRNA(His), whereas a mutant HXB2(His-AC-U152A160-GAC) reverted after culture to contain dual PBS complementary to tRNA(Lys,3) and tRNA(His), respectively. Our results demonstrate that regions in U5 act in concert with the PBS to promote use of the tRNA primer for initiation of reverse transcription. These results are discussed with respect to structural models for the U5-PBS interactions with tRNA.