shukoor65/lab-rag-model huggingface dataset:
Colorectal cancer in ulcerative colitis. Influence of anatomical extent and age at onset on colitis-cancer interval. We have examined the age at onset of both ulcerative colitis and colitis-associated colorectal cancer in 100 patients seen at Mount Sinai Hospital between 1959 and 1988. There were 85 patients with extensive colitis and 15 with left sided colitis. There was a strong direct correlation between the age at onset of ulcerative colitis and age at diagnosis of cancer (p less than 0.0001); this correlation was found both in patients with extensive colitis (p less than 0.0001) and in those with left sided colitis (p less than 0.005). Patients with left sided colitis developed both their colitis and their cancers about a decade later than did those with extensive disease, but the mean duration of colitis before diagnosis of cancer was virtually the same (about 21 years) in both groups, irrespective of the age at onset of disease.
Bilateral chylothorax. A 2.5-kg female developed bilateral chylothoraces 10 days after surgery for coarctation of the aorta. Initial conservative management consisted of intermittent positive pressure ventilation, drainage of chylous fluid and enteral feeding, but there was no diminution in loss of chyle. Ligation of the thoracic duct and pleurectomy were performed subsequently to reduce the large daily losses of chyle, amounting to nearly three times the child's circulating blood volume. Brawny oedema of the right upper quadrant of the body developed rapidly after the duct ligation and right pleurectomy. A further period of conservative treatment was required before the latter complication resolved. The literature relating to this iatrogenic complication and to fluid and nutritional losses in paediatric chylothorax is reviewed and discussed.
Congenitally corrected transposition and Ebstein's anomaly of the systemic atrioventricular valve: association with aortic arch obstruction. Aortic arch abnormalities are uncommon in patients with congenitally corrected transposition of the great arteries. Over a 20-year period, 10 patients with congenitally corrected transposition and Ebstein's anomaly of the systemic atrioventricular (AV) valve were identified. Five neonates had severe systemic AV valve regurgitation with severe coarctation of the aorta (n = 4) or aortic atresia (n = 1) and presented with heart failure. Four died in the neonatal period and one who had coarctation repair died 7 months postoperatively. The remaining five patients with congenitally corrected transposition and Ebstein's anomaly had mild left AV valve regurgitation; none of these had aortic arch obstruction. In neonates who have coexisting Ebstein's anomaly of the systemic AV valve and congenitally corrected transposition, obstruction to aortic arch flow is common. Severe systemic AV valve regurgitation with a morphologic systemic right ventricle may have contributed to low anterograde flow in the ascending aorta prenatally and thereby to the aortic arch abnormality.
Adenocarcinoma: an unusual presentation. A young pregnant woman had facial swelling in the upper nasal region. This was initially considered to be lymphedema in view of a history of past severe facial acne. A biopsy was done when the lesion progressed; the specimen showed adenocarcinoma. This responded well to radiotherapy, the favorable response being maintained for more than 24 months.
Indications for modification of coexisting dual atrioventricular node pathways in patients undergoing surgical ablation of accessory atrioventricular connections Concomitant susceptibility to atrioventricular (AV) node reentrant tachycardia has been demonstrated in certain patients having reentrant tachycardia utilizing accessory AV connections. For those patients undergoing accessory connection ablation, AV node surgical modification may be warranted during the same operative procedure. To assess indications for a combined operative procedure, this study evaluated potential predictors of subsequent spontaneous AV node reentrant tachycardia in patients undergoing ablation of accessory AV connections. Among 62 consecutive patients undergoing surgical ablation of an accessory AV connection, 13 (21%) manifested dual AV node pathways. The latter were identified preoperatively in five patients (four with concealed and one with bidirectional accessory connections) and postoperatively in seven (all seven with bidirectional accessory connections). In one patient with a bidirectional accessory connection, dual AV node pathways could not be demonstrated preoperatively, but AV node reentrant tachycardia was induced. Operative ablation of an accessory connection was successful in all patients. However, postoperatively, 2 of the 13 patients had inducible AV node reentrant tachycardia, 5 had AV node "echo" beats and 6 had no inducible arrhythmia. During 26 +/- 7 months of follow-up study, the two patients with inducible AV node reentrant tachycardia postoperatively had symptomatic AV node reentrant tachycardia. In addition, the one patient with inducible AV node reentrant tachycardia preoperatively had recurrence of this tachycardia 4 months after attempted surgical modification of the AV node. Consequently, although dual AV node pathways appear to be common in patients undergoing surgical ablation of an accessory AV connection (21%), only a small group (3 of 13) of these patients are at risk for subsequent clinical AV node reentrant tachycardia.
Patients with duodenitis have gastric secretory and motor functions like those of duodenal ulcer patients: results of a short-term treatment with ranitidine. Gastric acid secretion, gastric emptying of solids, and the effects of short-term treatment with 300 mg ranitidine at bedtime were evaluated in symptomatic patients with endoscopically and histologically proven duodenitis. The patients investigated had basal and pentagastrin-stimulated gastric acid hypersecretion, but normal gastric emptying times. Ranitidine brought about a significant improvement of endoscopic and histological features compared with the pretreatment findings. Endoscopic but not histological improvement was significantly better than with placebo. Furthermore, ranitidine brought about a significant reduction of weekly antacid consumption compared with placebo. Both ranitidine and placebo induced significant symptomatic improvement over basal conditions, but the difference between the two treatments did not reach statistical significance. Gastric secretory and motor functions, as well as the response to therapy, were similar in duodenitis patients with and without previous history of duodenal ulcer; the only exception was in antacid consumption, which was higher in the placebo group in those with past evidence of ulcer disease. Our results suggest that duodenitis patients have secretory and motor functions similar to those of duodenal ulcer patients. Therefore, further trials on large populations of duodenitis patients with antisecretory drugs are justified.
Differential effects of heptanol, potassium, and tetrodotoxin on reentrant ventricular tachycardia around a fixed obstacle in anisotropic myocardium BACKGROUND. The aim of this study was to test the hypothesis that electrical uncoupling and depression of the fast sodium channels have differential effects on propagation of the electrical impulse relative to the fiber orientation. METHODS AND RESULTS. In a model of reentrant ventricular tachycardia (VT) (mean cycle length, 144 +/- 13 msec) around a ring of anisotropic myocardium in 10 Langendorff-perfused rabbit hearts, the effects of extracellular K+ concentration [( K+]o) and heptanol were studied. [K+]o and heptanol each had a dose-dependent effect on VT cycle length. However, high [K+]o slowed the VT mainly by depressing longitudinal conduction, whereas heptanol preferentially depressed transverse conduction. The ratio between longitudinal and transverse conduction velocities progressively decreased with high [K+]o and progressively increased with heptanol. Heptanol terminated VT at a mean concentration of 3.5 +/- 0.5 mM. The cycle length before termination was 446 +/- 120 msec (p less than 0.001). In eight of 10 experiments, termination occurred by failure of conduction during transverse propagation. VT terminated at a mean [K+]o of 11.6 +/- 1.8 mM. The cycle length before termination was 493 +/- 341 msec (p less than 0.01). In seven of 10 cases, termination occurred by failure of conduction during longitudinal propagation. In the remaining five episodes (two with heptanol and three with high [K+]o), termination occurred by collision of the reentrant beat with an antidromic impulse being reflected within the ring. In a separate series of six hearts, tetrodotoxin was administered during VT. Like high [K+]o, tetrodotoxin prolonged the cycle length of the VT by preferentially slowing longitudinal conduction, and VT was terminated by longitudinal block. CONCLUSIONS. During reentrant VT, electrical uncoupling of cells by heptanol or modification of active membrane properties by high [K+]o or tetrodotoxin has a differential depressing effect on propagation of the impulse relative to the fiber orientation.
Effects of alterations in pulmonary function and sleep variables on survival in patients with amyotrophic lateral sclerosis. Breathing abnormalities and nocturnal hypoventilation occur in patients with amyotrophic lateral sclerosis (ALS). A prospective study was undertaken to determine the relationship of pulmonary function test abnormalities with quality of sleep and survival in 21 patients with ALS. Results of spirometry including determination of maximal respiratory pressures and arterial blood gases were compared with several formal polysomnographic variables and then also with 18-month survival. The patients had mild to moderate pulmonary function deficits, but the quality of sleep was best related to age (mean age, 58.5 years). The results of pulmonary function tests and arterial blood gas measurements did not correlate well with the presence of nocturnal breathing events or survival time, but the maximal inspiratory pressure was 86% sensitive for predicting the presence of a nocturnal oxygen saturation nadir of 80% or less and 100% sensitive for predicting 18-month survival. Although obstructive breathing events occurred, the primary explanation for the decline in nocturnal oxygen saturation was hypoventilation. We conclude that routine pulmonary function tests may be useful for screening for reductions in nocturnal oxygen saturation and also may have prognostic value. Further studies may determine whether treatment of nocturnal hypoventilation will have an effect on survival in patients with ALS who have breathing impairment.
Transition of Ki-67 index of uterine cervical tumors during radiation therapy. Immunohistochemical study. Histopathologic and Ki-67-staining features of cancer cells were investigated in biopsy specimens before and during radiation therapy in 29 patients with cervical squamous cell carcinoma. No morphologic changes were observed up to doses of 540 cGy. A few intact cancer cells remained up to doses of 2700 cGy. Moderate changes in the cancer cells were noticed in patients who received 900 cGy or more, i.e., multinuclei, swollen nuclei and cytoplasms, and prominent large nucleoli. At doses of 1800 cGy or greater, many cancer nests had severely damaged cancer cells with features such as cytolysis, karyolysis, karyorrhexis, pyknosis, and bizarre giant cells. There was no mitosis in the cells of patients who received doses greater than 1800 cGy. The Ki-67-positive cancer cells showed diffuse nuclear-stainings and dot-stainings before radiation therapy. Radiation doses more than 900 cGy changed the staining pattern of the Ki-67 antibody; large irregular spot-stainings and ring-stainings were observed predominantly. The Ki-67 index initially increased with the radiation dose; the mean Ki-67 indices before radiation therapy and at radiation doses of 180 cGy, 540 cGy, and 900 cGy were 41%, 50%, 63%, and 68%, respectively. The indices decreased when the dose was increased further, and they were 39% and 20% at doses of 1800 cGy and 2700 cGy, respectively. Possible explanations, including recruitment of quiescent cells, for the change in Ki-67 staining are discussed.
Posterior fossa intracranial hemorrhage in infants treated with extracorporeal membrane oxygenation: sonographic findings. Posterior fossa hemorrhage was documented by autopsy in five infants who had been treated with extracorporeal membrane oxygenation over a 5-year-period. In all five cases, the diagnosis was made prospectively by cranial sonography. Sonographic findings were compared with those in a control group of 15 infants with normal posterior fossae at autopsy. The following sonographic abnormalities were exhibited in neonates with posterior fossae hemorrhage: loss of definition of the cerebellum and fourth ventricle on midline sagittal images, heterogeneous cerebellar parenchyma, focal hypoechoic lesions, ventricular dilatation, and tentorial abnormalities. Bright foci inferior to the third ventricle were seen in four neonates in the normal control group. These foci measured 5-10 mm in diameter. One cranial sonogram was falsely interpreted as showing a posterior fossa hemorrhage because of prominent echoes in the interpeduncular cistern. Infants treated with extracorporeal membrane oxygenation are at risk for developing posterior fossa hemorrhage. Awareness of sonographic signs and potential pitfalls in the interpretation of posterior fossa hemorrhage is important for early and accurate recognition of these unusual and sometimes treatable hemorrhages.
Positive role of Clostridium difficile infection in diarrhea in infants and children. A retrospective review of children with Clostridium difficile infection and diarrhea identified 43 patients. Fifteen (35%) had immunoglobulins below the normal range for age, and typified those with transient hypogammaglobulinemia of infancy, because all increased their levels over the following 12 months. The age of those with hypogammaglobulinemia was significantly younger (p less than 0.01), averaging 18.8 months, than those with normal immunoglobulins who had a mean age of 4.6 yr. The number with recurrent C. difficile infection was significantly greater (p less than 0.001) in the hypogammaglobulinemic group than in those with normal immunoglobulins (46% vs 18%). Eleven children were identified who had C. difficile toxin in the stool after antibiotic therapy, but who had no diarrhea at the time of study. All had normal immunoglobulins. Control patients (20 without and 40 with diarrhea) had no evidence of C. difficile infection, and all but three had normal immunoglobulins. Three (7%) of those with diarrhea had IgA deficiency, and all had a diagnosis of milk protein allergy. These data suggest that immunoglobulin values be obtained in infants and children who have problematic C. difficile diarrhea in order to identify disorders of immunoglobulin synthesis which may be the underlying cause of repeated upper respiratory disease requiring antibiotic usage.
Variable regression of experimental bronchial preneoplasia during carcinogenesis. It has been thought that squamous severe atypical metaplasia of the bronchus is reliably precancerous. The canine subcutaneous bronchial autograft model for studying the progression of epidermoid carcinogenesis (normal----regular squamous metaplasia----mild, moderate, and severe atypical metaplasia----squamous cell carcinoma) provides evidence that severe atypical metaplasia of the bronchial epithelium is reversible. Among 148 subcutaneous bronchial autografts that had serial sampling of the epithelium and exposure to implants of methylcholanthrene, severe atypical metaplasia was noted in 28 that received only a single implant. During the total carcinogen exposure (median 24.5 months), 9 of 28 (32%) developed squamous cell cancer, and 19 of 28 (68%) regressed toward normal. Severe atypical metaplasia was noted in 34 subcutaneous bronchial autografts that received two or more carcinogen implants: epidermoid cancer developed in 26 of 34 (76.5%), and regression toward or to normal occurred in 8 of 34 (23.5%). Severe atypical metaplasia was not detected in 53 subcutaneous bronchial autografts: 19 that received only a single implant and 34 that received two or more implants. Progression and regression occurred among these subcutaneous bronchial autografts in proportions similar to those found in subcutaneous bronchial autografts wherein severe atypical metaplasia was seen. Among 33 subcutaneous bronchial autografts initially studied after 6 months of exposure to carcinogen, progression to severe atypical metaplasia was seen 3 months later in 19 of 33 that had additional exposure; in the same interval regression of epithelial abnormalities occurred in 14 of 33 subcutaneous bronchial autografts that had no additional exposure (p less than 0.05). We have presented evidence that severe atypical metaplasia includes at least three cell populations: one committed to cancer without further stimulus, one that regresses despite further carcinogen exposure, and one that requires additional carcinogen to progress to cancer. At least in this model, severe atypical metaplasia is not inexorably precancerous. The subcutaneous bronchial autograft model is suitable for seeking biologic indicators of irreversibility.
Spinal cord ischemia after resection of thoracoabdominal aortic aneurysms: MR findings in 24 patients. MR images of the thoracic spinal cord were made in 24 patients who developed signs and symptoms of spinal cord ischemia or infarction following surgery for a thoracoabdominal aortic aneurysm. Findings consisted primarily of four different patterns of signal abnormalities in the distribution of the anterior spinal artery. These abnormalities were identified as types A-D, depending on the degree of involvement of the gray matter and surrounding white matter. We found good correlation between the distribution of the signal abnormalities in the cord, the severity of the neurologic deficits, and the clinical outcome. MR is the imaging method of choice for diagnosing spinal cord ischemia or infarction. A thorough knowledge of the spinal cord arterial territories is crucial for characterizing ischemic MR signal abnormalities and for differentiating them from other causes of myelopathy.
Role of Neisseria gonorrhoeae and Chlamydia trachomatis in intraabdominal abscess formation in the rat. Our concept of the pathogenesis of acute salpingitis and advanced pelvic infection, such as tuboovarian abscess, is evolving. Although Neisseria gonorrhoeae and Chlamydia trachomatis are thought to play a significant role in acute pelvic inflammatory disease, other microorganisms, such as aerobes and anaerobes, have repeatedly been reported to play a significant role, also, particularly in the patient with advanced disease. A study was designed to evaluate the pathogenesis, and particularly any synergistic role, of some aerobes and anaerobes with N gonorrhoeae and C trachomatis abscess formation. Using the rat model developed by Weinstein and Onderdonk, the study demonstrated that N gonorrhoeae and C trachomatis alone do not produce abscesses. However, when combined with facultative or anaerobic bacteria, synergism with abscess formation is noted frequently. The data support the hypothesis that N gonorrhoeae and C trachomatis initiate infection and that aerobic and anaerobic bacteria act synergistically to produce abscesses. In addition, microorganisms not inoculated were found to be recruited into the infectious process. The organisms may gain access to the peritoneal cavity via the lower genital tract or from transmucosal migration from the intestinal flora.
Effect of clonidine on gallbladder contraction and small bowel transit time in insulin-treated diabetics. Cholelithiasis is more prevalent in diabetics than in nondiabetics. Gallbladder dysmotility is supposed to be one of the causative factors. Reduced alpha-adrenergic tone has been demonstrated in the enterocytes of diabetic rats, and its correction by clonidine might explain the beneficial effect that the drug has on diabetic diarrhea. We therefore surmised that diabetic cholecystoparesis could also be due to alpha-adrenergic alterations. To test this hypothesis, we studied gallbladder contractions by real time ultrasonography, and small bowel transit time by lactulose hydrogen breath test, in 13 insulin-requiring diabetics before and after administration of the alpha-adrenergic stimulant clonidine (0.3 mg orally). That plasma levels were sufficient was evidenced indirectly by a fall in blood pressure. Clonidine significantly improved the rate of emptying (0.0193 +/- 0.00057/min vs. 0.0318 +/- 0.0027/min; p less than 0.005), but not the fasting and residual gallbladder volumes. Small bowel transit time was significantly prolonged after clonidine (169 +/- 17 min vs. 208 +/- 17; p less than 0.05). These results suggest that 1) reduced alpha-adrenergic tone corrected by clonidine may be present in the diabetic gallbladder, and 2) clonidine's antidiarrheal effect might be explained, at least in part, by a prolongation of the small bowel transit time.
Relation between myocardial beta-adrenergic receptor and left ventricular function in patients with left ventricular volume overload due to chronic mitral regurgitation with or without aortic regurgitation. The relation between myocardial beta-adrenergic receptor and left ventricular (LV) function was studied in 10 patients, aged 41 to 61 years (average 51), with LV volume overload mainly due to chronic mitral regurgitation. Beta-adrenergic receptors were examined using crude membrane in LV papillary muscle obtained at mitral valve replacement. Cardiac function was evaluated at preoperative cardiac catheterization with the interval to surgery of 1 to 33 months (average 7). Beta-adrenergic receptor density in 7 patients with New York Heart Association class II or III congestive heart failure was higher than that in 3 patients with class IV heart failure (59 +/- 19 vs 37 +/- 3 fmol/mg protein, p less than 0.05). Beta-adrenergic receptor density showed a positive correlation with end-systolic stress/end-systolic volume index ratio, the index for contractile function (p less than 0.005). Other parameters such as cardiac index, pulmonary artery wedge pressure and LV ejection fraction had no significant correlation to beta-adrenergic receptor. The results demonstrated that increases in symptom and LV dysfunction, particularly of the contractile state, was associated with decreased myocardial beta-adrenergic receptor density from possible down-regulation in patients with chronic mitral regurgitation with or without aortic regurgitation.
Serum neuron-specific enolase levels after subarachnoid hemorrhage. We examined serum levels of neuron-specific enolase by enzyme immunoassay in 29 patients with subarachnoid hemorrhage due to ruptured cerebral aneurysm. Serum neuron-specific enolase levels were significantly higher in patients with a poor neurological status than in patients with a good neurological status on admission, and the greater the amount of subarachnoid blood, the higher the serum neuron-specific enolase level. Patients with a good outcome had low serum neuron-specific enolase levels throughout their courses. Serum neuron-specific enolase levels increased with development of delayed ischemic neurological deficits and, especially in poor outcome patients, high levels persisted until 3 weeks after the subarachnoid hemorrhage.