shukoor65/lab-rag-model huggingface dataset:
C5a, cutaneous mast cells, and inflammation: in vitro and in vivo studies in a murine model. To evaluate further the interactions of C5a and mast cells in cutaneous inflammation, the ability of human native C5a (nC5a) (10 to 500 ng/ml) and human recombinant C5a (rC5a) (10 ng/ml to 100 ng/ml) to induce histamine release from purified BALB/c cutaneous mast cells (CMC) and peritoneal mast cells (PMC) was analyzed. It was found that nC5a induced histamine release from CMC but not from PMC, with a maximal net release at 250 ng/ml nC5a (22.8 +/- 2.6%). Kinetic experiments demonstrated that nC5a-induced maximal net histamine release occurred 5 min after the presentation of this stimulus (25.8 +/- 6.0%). Using rC5a and CMC, dose-response studies indicated a maximal net release of 7.0 +/- 1.7% at rC5a of 10 ng/ml, and kinetic studies showed a maximal net release at 5 min of incubation (12.9 +/- 1.6%). Release induced by rC5a was calcium-dependent, and peaked at 30 degrees C. These results indicate that functional heterogeneity exists between the CMC and the PMC of BALB/c mice, that C5a is a relevant stimulus for characterization of this heterogeneity, and that CMC from these animals can serve as a convenient in vitro model for the study of human C5a-mast cell interactions. In vivo, injections of nC5a (25-100 ng) and rC5a (25-100 ng) into the skin of BALB/c mice induced an increase in cutaneous vasopermeability, as assessed by the extravasation of intravenously injected 125I-bovine serum albumin. nC5a induced a dose-dependent increase in vasopermeability, whereas alterations induced by rC5a plateaued at 50 ng. The C5a-induced vasopermeability was markedly enhanced in animals that had been previously treated with an inhibitor of serum carboxypeptidase, which converts C5a to the less potent derivative, C5a des Arg. These findings suggest that carboxypeptidase plays an important role in vivo in the modulation of C5a-induced cutaneous inflammation in murine skin.
Elevated intravesical pressure causes arterial hypoperfusion in canine colocystoplasty: a fluorometric assessment. Since 1988 there have been 15 reported cases of late, spontaneously ruptured intestinal cystoplasties at bowel sites remote from the anastomosis. Ischemic necrosis has been suggested as a possible etiology. We examined this hypothesis by quantifying the uptake of intravascular fluorescein in the augmented bowel of adult mongrel canines. There was a statistically significant decrease in fluorescein uptake at high intravesical pressures, which appeared to be most pronounced at the antimesenteric border. This laboratory study supports a recent clinical report of histological changes pathognomonic for chronic ischemia in the augmented bowel of patients with spontaneous rupture.
Predictive value of ventricular arrhythmias for patency of the infarct-related coronary artery after thrombolytic therapy. In animal studies reperfusion of coronary arteries is commonly accompanied by ventricular arrhythmias. It is not certain, however, whether ventricular arrhythmias can be used as a reliable non-invasive marker of reperfusion in humans. Two-channel Holter recordings were obtained from the start of an intravenous infusion of streptokinase until coronary angiography (2.8 (2.7) hours (mean SD)) afterwards) in 57 patients with acute myocardial infarction of less than four hours who were generally not treated with antiarrhythmic drugs. Ventricular arrhythmias occurred in 21 (37%) of the 57 patients: accelerated idioventricular rhythm in 13 patients and non-sustained ventricular tachycardia in 15 patients. Seven patients had both accelerated idioventricular rhythm and non-sustained ventricular tachycardia. Coronary angiography showed a patent infarct-related vessel in 12 (92%) of the 13 patients with accelerated idioventricular rhythm (95% confidence interval 66 to 99%), in 22 (50%) of the 44 patients without accelerated idioventricular rhythm (95% CI 34 to 66%), in 11 (73%) of the 15 patients with non-sustained ventricular tachycardia (95% CI 45 to 92%), and in 23 (55%) (95% CI 39 to 71%) of the 42 patients who did not have non-sustained ventricular tachycardia. Seventeen (81%) of the 21 patients with accelerated idioventricular rhythm, or non-sustained ventricular tachycardia, or both, had a patent infarct-related vessel (95% CI 58 to 94%) as did 17 (47%) of the 36 patients with no ventricular arrhythmia (95% CI 29 to 65%). In patients with accelerated idioventricular rhythm after thrombolysis the infarct-related vessel is almost certain to be patent; but the infarct-related coronary artery can still be patent when no arrhythmia is seen.
Atypical hyperplasia of the breast: mammographic appearance and histologic correlation. The mammograms and histologic slides of 58 cases of atypical hyperplasia (AH) of the breast were retrospectively reviewed to determine the geographic correlation (direct, near, or remote) between mammographic abnormalities (if present) and the histologic findings. A direct mammographic-histologic correlation was found in 24 of the 58 cases (41%), near correlation in 15 (26%), and remote correlation in 19 (33%). Clustered microcalcifications were the most common mammographic abnormality that was directly correlated with AH at histologic examination. Atypical ductal hyperplasia was much more frequently associated with a direct mammographic-histologic correlation than was atypical lobular hyperplasia (48% vs 9%). The authors conclude that, although no pathognomonic appearance of AH was discovered, mammographic abnormalities similar to those of small cancers could be directly correlated with histologic findings in 41% of cases. Since AH has been shown to be associated with a five- to tenfold increased risk of subsequent invasive carcinoma, frequent clinical and at least yearly mammographic follow-up is suggested once AH is discovered.
A randomized study of closure of the peritoneum at cesarean delivery. This study was conducted to test the hypothesis that nonclosure of the visceral and parietal peritoneum during low transverse cervical cesarean delivery is not associated with increased intraoperative or immediate postoperative complications. One hundred thirteen patients scheduled for low transverse cervical cesarean were randomized to either closure of both the visceral and parietal peritoneum with absorbable suture (N = 59) or no peritoneal closure (N = 54). Patients were cared for in the usual postoperative manner without reference to treatment group. There were no demographic differences between the groups and no differences in method(s) of anesthesia, operative indication(s), or use of peripartum epidural narcotics. The incidence of fever, endometritis, or wound infection was similar between groups. There were no differences in the number of patients requiring parenteral narcotic analgesia or in the number of doses per patient. The number of oral analgesic doses was significantly greater with closure than without (P = .014). The frequency with which postoperative ileus was diagnosed in each group was similar, and there was no difference regarding the day on which patients were advanced to liquid or select diets. Bowel stimulants were administered more frequently to the closure than to non-closure patients (P = .03). The average operating time was shorter for the open group than for the closure group (P less than .005). We conclude that non-closure of the visceral and parietal peritoneum at low transverse cervical cesarean delivery appears to have no adverse effect on immediate postoperative recovery, may decrease postoperative narcotic requirements, allows less complicated return of bowel function, and provides a simplified and shorter surgical procedure.
Experience with the first 250 endometrial resections for menorrhagia [published erratum appears in Lancet 1991 Jan 1;337(8753):1362] 234 patients with menorrhagia were treated hysteroscopically by transcervical resection of the endometrium (TCRE) instead of hysterectomy. 250 procedures were performed under general anaesthesia (63%) or under sedation plus local anaesthesia (38%). The endometrium was excised either totally (91%) or partially (9%) in all but one case, and 56 (22%) of the patients underwent simultaneous resection of submucous fibroids. Surgical time (range 10-100 min) varied with the gynaecologist's experience. 479 ml was the average volume of uterine irrigant absorbed by the patient. Blood loss was usually slight. Operative complications were uncommon, but 4 (2%) women sustained a uterine perforation (without serious sequelae), 7 (3%) absorbed more than 2 litres of fluid, and 1 required tamponade to control postoperative bleeding. Hospital stay was short and full recovery usual by 1-2 weeks. Menstrual symptoms improved in over 90% of the patients throughout the follow-up of up to 2 1/2 years; 27-42% of the women became amenorrhoeic at some time after total TCRE. Results were best in women greater than 35 years of age, but was not influenced by the presence of fibroids or pretreatment dysmenorrhoea. 10 (4%) women later underwent hysterectomy. Hysteroscopy 3 and 12 months after surgery revealed a small, fibrotic uterine cavity in the majority.
Pathologic fibrosis and matrix connective tissue in the subaortic myocardium of patients with hypertrophic cardiomyopathy. To evaluate scar-type and matrix connective tissue and to assess their role in the diastolic dysfunction of hypertrophic cardiomyopathy, surgically resected subaortic myectomy specimens and several autopsy hearts from patients with hypertrophic cardiomyopathy were studied. Eighteen specimens were differentially stained by a newly developed method that precisely determines relative collagen content; these tissues were compared with postmortem hypertrophied and normal control subaortic specimens. Quantitation revealed a 72% higher level (36.5 vs. 22.1 micrograms collagen/mg protein) of stainable collagen in the hearts with hypertrophic cardiomyopathy than in hypertrophied control hearts. The endocardial plaque was quantitated morphometrically, and it constituted only 4.6 +/- 1.7% of the total increased collagen content in the cardiomyopathy specimens. For the matrix studies, the cardiomyopathy specimens were stained by a silver impregnation technique that identifies connective tissue elements not normally visible with routine histologic methods. There was a marked increase in content of all matrix components, both in areas of pathologic scarring and in "normal" zones. Whorls of matrix connective tissue were noted in regions of myocyte whorls, as well as independent of them. Thus, these studies revealed a striking increase of both scar-type and matrix connective tissue in hypertrophic cardiomyopathy. The extensive scarring and the pronounced interstitial and intercellular matrix connective tissue may contribute to the increased ventricular chamber stiffness and impaired relaxation in this disease.
Growth of tracheal anastomoses: advantage of absorbable interrupted sutures [published erratum appears in Ann Thorac Surg 1991 Jul;52(1):176] Growth of the trachea after complete transection and anastomosis was studied in four groups of 1-month-old New Zealand white rabbits. The trachea was transected at the fifth cartilaginous ring and then anastomosed with continuous 6-0 polypropylene (Prolene) (group 1), interrupted 6-0 polypropylene (group 2), continuous 6-0 polydioxanone (PDS) (group 3), or interrupted 6-0 PDS (group 4). The animals were followed up for 90 to 103 days (mean follow-up, 95 days). At the time the animals were killed, body weight had increased 125% (1.2 to 2.7 +/- 0.18 kg). Growth of the trachea was assessed at the time of death. Results from this study suggest that growth of a tracheal anastomosis is retarded in a growing animal model. The degree of resultant stenosis was significantly less when an absorbable suture material (PDS) and an interrupted suturing technique were used.
Impedance plethysmography: a new method for continuous muscle perfusion monitoring. Vigilant postoperative monitoring of the buried muscle flap is critical after free transfer because early diagnosis of vascular insufficiency is essential to allow prompt correction. We have identified a monitoring method utilizing needle electrodes and impedance plethysmography that gives a beat-to-beat representation of muscular perfusion. In 25 New Zealand White rabbits the gastrocnemius muscle was isolated on its vascular pedicle, and two intramuscular needle electrodes were placed. The instantaneous impedance changes of the muscle (corresponding to the pulsatile volume changes of perfusion) were measured and recorded. Using this representation of perfusion, an independent judge was able to correctly diagnose muscular ischemia 100 percent of the time (n = 25). Further, the judge was able to correctly distinguish the ischemia as arterial (n = 10) or venous (n = 10) in origin 100 percent of the time. Additionally, we monitored muscle perfusion transcutaneously in five free muscle flaps and demonstrated a reliable impedance signal that correlated with perfusion.
Sclerosing vasculopathy of the central nervous system in nonelderly demented patients. Three nonelderly patients without hypertension whose clinical and radiologic features otherwise resembled Binswanger's subcortical arteriosclerotic encephalopathy underwent biopsy of the hyperintense periventricular lesions seen on magnetic resonance imaging. The pathologic findings of the periventricular lesions consisted of gliosis with mild rarefaction and edema of the white matter. All patients had a sclerosing vasculopathy of unknown cause, which involved numerous small vessels within the periventricular lesions. The vessels stained negatively for amyloid, amyloid precursors, desmin, vimentin, keratin, immunoglobulin, and complement. On electron microscopy, small arteries, arterioles, venules, and capillaries were characterized by swollen astrocytic foot processes surrounding the vessels; dense, perivascular collagen packing; crystalline arrays of filaments within basement membrane; giant lipid-laden lysosomes within perivascular cells; and narrowing of the vascular lumina. Similar changes were not seen in a control group of 19 patients. The pathologic features of the vessels in these cases are distinct from the vasculopathy associated with Binswanger's subcortical arteriosclerotic encephalopathy. We suggest that a spectrum of vasculopathies may be associated with dementia and periventricular hyperintense lesions on magnetic resonance imaging.
Invasive treatment of pancreatic fluid collections with surgical and nonsurgical methods. Pancreatic fluid collections (PFC) can be drained surgically or nonsurgically with endoscopic or radiologic techniques. To define subgroups of patients with PFC who would benefit from the new modalities, we reviewed a period (1977 to 1990) during which both surgical and nonsurgical invasive techniques were available. Patients with phlegmon or necrosis at initial diagnosis were excluded. Sixty-five patients (35 male, 30 female) underwent 1 or more drainage procedures. A mean postprocedure follow-up of 10.2 months was available for 59 patients. Initial management was nonsurgical in 80% of patients. Procedures in patients with follow-up comprised invasive nonsurgical drainage (n = 25), invasive nonsurgical drainage plus surgery (n = 22), and surgery only (n = 12). Results for each group, respectively, were: morbidity, 20%, 20%, and 24%; mortality, 8%, 5%, and 0%; and successful drainage, 92%, 82%, and 83%. The choice of management appeared to be based on etiology and radiologic characteristics. Patients with nonalcohol- and nonbiliary-associated pancreatitis without a radiographically defined wall were more common in the invasive nonsurgical group and were successfully treated without surgery. Nonsurgical invasive techniques are efficacious in the treatment of PFC in this subgroup of patients.
Seromuscular enterocystoplasty in rats. Enterocystoplasty is commonly used in clinical practice. Many of its undesirable effects, that is infections, stones, mucus production, absorption of urinary components into the blood stream and risk of cancer, result from the intestinal mucosa lining the urinary tract. We report on the feasibility of creating an enterocytoplasty with a seromuscular colonic segment that acquires a transitional epithelial lining. Augmentation enterocystoplasty was performed in 51 male, 500 gm., Sprague-Dawley rats with a 1.82 cm.2 patch of left colon from which the mucosa had been stripped. The serosal surface was used as lining for the enterocystoplasty. The intestinal patch and the bladder capacity at known pressure were measured at operation and at sacrifice. The histology of the enterocystoplasty was studied in detail following sacrifice. Of the animals 40 survived without significant complications and were sacrificed at a mean postoperative time of 30 days (range 5 to 80 days). In the remaining 11 rats a bladder stone developed but it did not seem to affect the outcome of the experiment. The size of the patch could be measured in 22 rats: it was 1.82 cm.2 (standard deviation +/- 0.86) at operation and 2.30 cm.2 (standard deviation +/- 1.1) at sacrifice. In none of the rats did the patch decrease in size. The bladder capacity at a known pressure (mean 17 cm. water) could be measured in 26 animals: it was 2.35 ml. (standard deviation +/- 0.65) at operation and 5.18 ml. (standard deviation +/- 1.19) at sacrifice. Histological analysis was done in 40 rats. In all cases the serosal surface was lined with transitional epithelium, there was no fibrosis or inflammation and the structure of the muscular layer of the bowel remained intact. The earliest growth of uroepithelium in the serosal surface of the bowel was noted at 5 days. This model suggests that the seromuscular enterocystoplasty can be constructed successfully in the rat model. The seromuscular intestinal patch does not shrink. The bladder capacity increases and histology shows a uroepithelial lining of the augmentation.
Obesity: types and treatments. Causes of obesity include a low resting metabolic rate, environmental factors, family behavior patterns, a poorly developed satiety response and reactive eating due to stress or anxiety. Morbid obesity is characterized by an increased number of adipocytes and a degree of irreversibility. Overeating increases the size of adipocytes; however, once adipocytes achieve their maximal size, proliferation is induced and massive, irreversible obesity may result. A syndrome of restrained eating produced by chronic dieting leads to hunger, frustration and rebound overeating. Treatment may be unsuccessful because of the failure to address specific causes of obesity in individual patients and the use of reducing regimens that are not designed to maintain weight loss. Recognition of the diverse clinical forms of obesity and their different etiologies permits treatment regimens to be more specific, increasing the likelihood of success. Even with this approach, treatment failure is common.
Transmembrane domain length variation in the evolution of major histocompatibility complex class I genes. The fifth exons of major histocompatibility complex (MHC) class I genes encode a transmembrane domain (TM) that is largely responsible for class I antigen cell-surface expression usually through conventional hydrophobic amino acid-membrane interactions or, less often, through phosphatidylinositol linkage. In this report we show that Peromyscus leucopus, a Cricetidae rodent, has MHC class I genes (Pele-A genes) encoding three distinct sizes of TMs. Increases in TM lengths were due to tandem duplications of sequences similar to human hypervariable minisatellite repeats and the lambda chi site. We discerned remnants of a similar duplication event in comparable rodent and primate MHC class I genes. Furthermore, several duplications and deletions appear to have occurred independently in H-2, RT1, Pele-A, and ChLA genes in near-identical positions. Accumulated data suggests that sequences in the fifth exon of MHC class I genes may, therefore, constitute a mutational or recombinational hot spot that is mediated by minisatellite- and chi-like sequences imbedded within the coding region. The MHC class I genes may thus have recruited "selfish" DNA in their evolution to encode cell surface proteins. Expression of Pele-A genes was examined by the polymerase chain reaction (PCR) using oligonucleotide primers specific for exon 4 and 5 sequences. The PCR product sizes indicated that genes encoding each TM domain length are ubiquitously transcribed.
The use of FDG-PET in the detection and management of malignant lymphoma: correlation of uptake with prognosis. Twenty-one patients with untreated malignant lymphoma in the head and neck region were evaluated with positron emission tomography (PET) using fluorine-18-fluorodeoxyglucose (FDG) and gallium-67 SPECT imaging. Tumor-to-normal soft-tissue contrast ratios (TCRs) obtained 60 min after injection of FDG were higher than 2.6, and all malignant lymphomas were clearly visualized. In patients with poor prognosis, higher TCRs and glucose utilization rates (GURs) were observed, whereas low TCR and GUR were shown in a patient with low-grade malignancy. In comparison with 67Ga scintigraphy, patients with high TCRs and GURs were likely to show increased accumulation of gallium-67, but accumulation of gallium-67 was not increased as much as FDG in poor prognostic patients. FDG-PET may be useful in the detection and management of malignant lymphoma.
Campylobacter enteritis--New Zealand, 1990. In August-September 1990, an outbreak of Campylobacter enteritis occurred at a camp near Christchurch, New Zealand. This report provides a preliminary summary of the investigation of this outbreak by the New Zealand Communicable Disease Centre and the Canterbury Area Health Board.
Usefulness of transesophageal echocardiography in the diagnosis of conditions mimicking aortic dissection. Between September 1987 and April 1989, forty patients suspected to have aortic dissection were evaluated by transesophageal echocardiography. Aortic dissection was identified in 18 patients. This study evaluated the ability of transesophageal echocardiography in the assessment of the 22 patients in whom aortic dissection was not found. A range of pathologic conditions was diagnosed in these patients. Five patients had ischemic heart disease when they were initially seen. Among the remaining 17 only one patient had a normal aorta. Aortic disease was present in the other 16 patients with aortic dilatation in 10. Atheromas were detected in seven patients with concomitant aortic dilatation in five of them. An extrinsic aortic mass was present in two patients. Transesophageal echocardiography correctly identified an anastomotic leak at the site of left coronary artery implantation in a patient with a recent Bentall procedure, and a large mobile clot within the proximal descending aorta in a patient with blunt chest trauma. These findings obviated the need for other tests in 15 patients and led to surgery in four with no ancillary tests performed in three of them. Thus transesophageal echocardiography has an important role in assessing patients with suspected dissection. Aortic disease is common even in patients in whom aortic dissection is excluded, and some of the conditions can be just as life-threatening as dissection. Transesophageal echocardiography not only reliably identifies dissection but can also detect luminal and extraluminal diseases not adequately visualized by other modalities.