shukoor65/lab-rag-model huggingface dataset:
Analysis and interpretation of treatment effects in subgroups of patients in randomized clinical trials. A key principle for interpretation of subgroup results is that quantitative interactions (differences in degree) are much more likely than qualitative interactions (differences in kind). Quantitative interactions are likely to be truly present whether or not they are apparent, whereas apparent qualitative interactions should generally be disbelieved as they have usually not been replicated consistently. Therefore, the overall trial result is usually a better guide to the direction of effect in subgroups than the apparent effect observed within a subgroup. Failure to specify prior hypotheses, to account for multiple comparisons, or to correct P values increases the chance of finding spurious subgroup effects. Conversely, inadequate sample size, classification of patients into the wrong subgroup, and low power of tests of interaction make finding true subgroup effects difficult. We recommend examining the architecture of the entire set of subgroups within a trial, analyzing similar subgroups across independent trials, and interpreting the evidence in the context of known biologic mechanisms and patient prognosis.
Ventricular dysfunction does occur during liver transplantation. Ventricular dysfunction, then, does indeed occur during liver transplantation, particularly at the time of reperfusion. Pulmonary embolism contributes to right ventricular and right atrial encroachment on left-heart filling, and paradoxical embolism may occur. Pericardial effusions, tricuspid regurgitation, hypothermia, and the release of substances, particularly potassium from the donor liver, may further contribute to compromises in ventricular function. Proper monitoring and appropriate treatment, however, lead to successful operative outcomes in most cases.
Effects of alfentanil and fentanyl on induction of anaesthesia in patients with severe pregnancy-induced hypertension. Forty patients with severe pregnancy-induced hypertension presenting for Caesarean section under general anaesthesia were allocated randomly to receive either fentanyl 2.5 micrograms kg-1 or alfentanil 10 micrograms kg-1 as part of the anaesthetic induction sequence. In all patients, the cardiovascular response to tracheal intubation was measured. Both drugs attenuated the response equally but did not abolish it in all patients. Alfentanil 10 micrograms kg-1 is a suitable alternative to fentanyl 2.5 micrograms kg-1 for patients with pregnancy-induced hypertension.
Hemangioma of the nasal vault: MR and CT features. Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition.
Sarcomatous change in a teratoma after treatment of testicular carcinoma. Treatment can transform the metastases of nonseminomatous germ cell carcinoma into histologically mature teratoma. These lesions typically have a benign clinical course. The authors present a case of leiomyosarcoma occurring within such a lesion. It arose 18 years after therapy for metastatic embryonal carcinoma of the testis and appears to have been radiation induced.
Ossicular chain reconstruction: a combined prosthesis with organic and synthetic material. The surgical techniques to restore the sound pressure transfer mechanism in surgery of chronic otitis media are still in an evolutionary stage. Ossicular interposition is effective and certainly is not controversial. The use of various organic prostheses has been criticized. The prosthesis with a shaft of Teflon and a homograft bone flange is an alternative method which has been successful in our hands.
Polycystic ovaries: do these represent a specific endocrinopathy? Serum pituitary gonadotrophins, oestradiol, testosterone and insulin pulse patterns were examined at 15-min intervals for 6 h in 40 women with a previous diagnosis of polycystic ovarian disease (PCO) based on clinical, endocrinological and ultrasound data. Age, duration of symptoms, body mass index (BMI) and ovarian volume showed no correlation with the 6-h mean value of any hormone and testosterone blood levels did not correlate with those of insulin. Some patients had high and others low LH pulse pattern components, and few had an inverted LH:FSH ratio. Morphological polycystic ovarian changes may be a reflection of various rather than a single pattern of gonadotrophin secretion.
Interferon-gamma inhibits arterial stenosis after injury. BACKGROUND. Arterial injury initiates a proliferative response among the smooth muscle cells of the artery. This leads to the formation of a thickened intima that may reduce the diameter of the arterial lumen. Such intimal lesions often develop after vascular surgery and angioplastic procedures. Previous cell culture studies have shown that the lymphokine, interferon-gamma (gIFN), inhibits smooth muscle cell proliferation. METHODS AND RESULTS. We therefore tested whether administration of exogenous gIFN could inhibit the development of intimal lesions. Rat carotid arteries were denuded with a balloon catheter, resulting in the formation of a standardized intimal lesion. The animals were then treated with recombinant rat gIFN at 200,000 units (approximately 400,000 units or 100 micrograms/kg body wt) administered parenterally once daily for 7 days. Autoradiographic analysis of 3H-thymidine incorporation revealed that gIFN reduced the early smooth muscle replication by approximately 75%. gIFN treatment for 1 week resulted in a 50% reduction of intimal cross-section area at 2 weeks after injury when compared to control rats injected with buffer alone. The difference in lesion development persisted in rats analyzed 10 weeks after injury, suggesting that proliferative events during the first week determine the long-term development of the intima. Inhibition of lesion development was accompanied by expression of the class II histocompatibility (Ia) gene, RT1B, suggesting that both were directly related to the administration of gIFN. CONCLUSIONS. These results show that gIFN is a potent inhibitor of the formation of arterial proliferative lesions in vivo. It is possible that gIFN could be useful in preventing arterial stenosis after surgery and angioplasty in man.
Changes in neutrophil met-enkephalin containing peptides in episodic cluster headache. We have previously demonstrated an increase in plasma met-enkephalin levels during the pain attacks in episodic cluster headache. The present study was undertaken in order to clarify the source of the plasma met-enkephalin increase. Recent evidence has shown that peripheral blood polymorphonuclear cells contain peptides derived from the proenkephalin A system, which can be released by specific stimuli. We studied neutrophil met-enkephalin containing peptides (NMECP) in 27 episodic cluster headache patients: 24 in a cluster period (6 of them during a pain attack), and 3 in the remission period. Neutrophil met-enkephalin containing peptide levels (after sequential enzymatic digestion with trypsin and carboxypeptidase B) were determined by radioimmunoassay with specific antiserum. Neutrophil peptide concentration (pmol/mg prot) was lower (p less than 0.01) in patients during the pain attack (14.4 +/- 0.36) than after their pain had subsided (36.7 +/- 0.31) and lower than in the remission period patients (35.8 +/- 0.4). We conclude that neutrophil met-enkephalin containing peptides decrease during pain in episodic cluster headache, and that they may be involved in the concomitant plasma met-enkephalin increase.
Early abdominal complications following heart and heart-lung transplantation. In the first 11 years of the heart and heart-lung transplantation programme at Papworth Hospital, Cambridge, 356 patients underwent heart transplantation, and 73 patients received both heart and lungs. Out of 429 patients 41 (9.5 per cent) developed abdominal complications within the first 30 days, and 20 of the 41 required surgery. The complications included pancreatitis (10), peptic ulceration (8), and pseudo-obstruction (8), in addition to colonic perforation and small bowel obstruction. When laparotomy was performed it was well tolerated. This paper supports the view that successful management of abdominal complications following transplantation requires prompt diagnosis and treatment. Where doubt exists in the presence of an acute abdomen, laparotomy is the appropriate way to establish a definitive diagnosis.
Ewing's sarcoma in children: twenty-five years of experience at the Instituto Portuges de Oncologia de Francisco Gentil (I.P.O.F.G.). Fifty children with Ewing's sarcoma were consecutively treated from 1962 to 1987 and retrospectively analyzed at the I.P.O.F.G. of Lisbon. At first diagnosis, 10 cases had distant metastases. The remaining 40 patients had clinically localized disease, and different protocols were followed over the years. The best results were obtained with chemotherapy and radiotherapy with or without surgery; and for these children the two-year survival rate was 42.8% vs. 8.3% for the group of patients submitted to local treatment alone. Besides the treatment modality, other factors influenced the prognosis, such as inflammatory signs, sex, tumor volume, and tumor site as well as evidence of distant metastases.
The role of epidermal growth factor in the pathogenesis of peptic ulcer disease. Duodenal biopsies obtained from seven normal subjects and six ulcerous patients were cultured in vitro for 30 min at 37 degrees C under various experimental conditions. Epidermal growth factor (EGF) and somatostatin released in the culture medium were determined by radioimmunoassay. Under basal conditions, EGF and somatostatin levels were significantly higher in normal subjects (11.49 +/- 3.07 ng/mg protein and 3.06 +/- 0.8 ng/mg protein, respectively) than in ulcerous patients (6.9 +/- 1.98 ng/mg protein and 1.75 +/- 1.23 ng/mg protein, respectively). However, when antibodies to somatostatin and vasoactive intestinal polypeptide (VIP) were added together to the culture media, in ulcerous patients, EGF levels also were lower as absolute values, but were higher as a percentage of variation than controls (p less than 0.05). The fall of EGF secretion from tissue cultures of ulcerous patients could be the consequence of endocrine cellular loss or damage, rather than the cause of ulceration. Moreover, the EGF-producing cells around the lesion in ulcerous patients seems to be hyperactive, and this hyperfunction of EGF-producing cells might contribute to the in vivo repair of tissue damage.
Validation of hourly pain intensity profiles with chronic pain patients. This study examines how empirically derived pain intensity profiles relate to psychological adjustment in chronic pain patients. Hourly pain intensity ratings over the course of a day of 189 chronic pain patients were categorized into 6 groups using a hierarchical regression analysis technique. The profiles reflected linear, curvilinear, multilinear or "no profile" effects. Judges' ratings of pain intensity profiles were found to be less reliable than ratings based on empirical analysis. The majority of patients showed linear profiles while 26% of the patients showed no consistent relationship between hourly pain intensity and time of day. Patients who showed no consistent trend in their pain ratings reported having significantly higher ratings of emotional distress. They tended to have conflicts at home and showed more pain behavior than patients who had a distinct pain profile. Support is given for the potential clinical utility of pain rating profiles.
Intrathoracic complications following allogeneic bone marrow transplantation: CT findings. The authors retrospectively reviewed computed tomographic (CT) scans of 18 patients who developed 21 episodes of intrathoracic complications after allogeneic bone marrow transplantation (BMT). Pathologic and/or microbiologic diagnoses were available for all patients. All patients were immunocompromised due to either graft-versus-host disease (GVHD), neutropenia, or recurrent malignancy after BMT. CT demonstrated diagnostically relevant findings that were not apparent at radiography in 12 of the 21 cases (57%). These included a ground-glass pattern in early pneumonia (n = 5); a peripheral distribution in GVHD, bronchiolitis obliterans organizing pneumonia, and eosinophilic drug reaction (n = 4); cavitating lesions in Pneumocystis carinii pneumonia (n = 1); hemorrhagic infarcts in aspergillosis (n = 1); and mediastinal adenopathy in recurrent Hodgkin disease (n = 1). The authors conclude that chest CT is superior to radiography in demonstrating the presence, distribution, and extent of intrathoracic complications developing in patients after allogeneic BMT. CT is useful in guiding procedures for tissue diagnosis.
Caesarean section in undiagnosed Eisenmenger's syndrome. Report of a patient with a fatal outcome. An obstetric patient is described in whom the first sign of cardiac disease was unexplained hypoxaemia during emergency anaesthesia for antepartum haemorrhage, with an eventual fatal outcome. The case highlights the importance of patient information at the booking clinic, and the implications of a raised haemaglobin in early pregnancy.
Acute airway obstruction, hypertension and kyphoscoliosis. An elderly woman developed acute respiratory obstruction after choking on a bolus of food. On rigid bronchoscopy no foreign body, or anatomical obstruction was seen, but airway obstruction recurred during emergence from general anaesthesia, and was thought to be functional in nature. A recurring airway obstruction followed, relieved by induction of anaesthesia and by sedation. This was subsequently demonstrated to be caused by a tortuous aorta which impinged intermittently on the anterior tracheal wall, as a result of kyphoscoliosis of the thoracic spine. We attribute the relief of airway obstruction by general anaesthesia to a reduction in arterial blood pressure.
Serum immune response to Helicobacter pylori in children: epidemiologic and clinical applications. Antibody responses to Helicobacter pylori were measured by a solid-phase whole-cell enzyme-linked immunosorbent assay in 150 children and adolescents; in 47 consecutive children undergoing upper gastrointestinal endoscopy, including 17 with H. pylori infection before and after antimicrobial treatment; and in 46 family members of the infected children. Abnormal levels of either IgG or IgA were found in 6% of the 150 children. In the latter group the prevalence of H. pylori seropositivity increased with age. Parents and siblings of the infected children had 94% and 71% seropositivity, respectively, suggesting intrafamilial spread. Abnormal levels of IgG or IgA against H. pylori identified infected children with 95% sensitivity and 84% specificity. Eradication of the infection was accompanied by a significant decrease in IgG and IgA titers, with normalization in 10 cured patients in 12 months or less. We conclude that the method described for evaluation of H. pylori-specific IgG and IgA antibodies gives helpful information on the epidemiology of the infection and represents a useful adjunct to diagnosis and management of chronic gastritis in children.
Molecular epidemiology and the genetics of environmental cancer. Environmental, occupational, and recreational exposures to carcinogens contribute to cancer risk in humans. Cancer formation is a multistage process involving tumor initiation, promotion, conversion, and progression. Carcinogens can affect any of these stages through genetic and epigenetic mechanisms. The association of a suspected carcinogenic exposure and cancer risk can be studied in populations with classic epidemiologic techniques. However, these techniques are not applicable to the assessment of risk in individuals. Molecular epidemiology, in contrast, is a field that integrates molecular biology, in vitro and in vivo laboratory models, biochemistry, and epidemiology to infer individual cancer risk. Carcinogen-macromolecular adduct levels, and somatic cell mutations can be measured to determine the biologically effective dose of a carcinogen. Molecular epidemiology also explores host cancer susceptibilities, such as carcinogen metabolic activation, DNA repair, endogenous mutation rates, and inheritance of mutated tumor suppressor genes. Substantial interindividual variation for each of these biologic end points has been shown and, therefore, highlights the need for assessing cancer risk on an individual basis. Given the pace of the last decade, it is feasible that the next 10 years will allow molecular epidemiologists to develop a cancer-risk profile for an individual that includes assessment of a number of factors. This will help focus preventive strategies and strengthen quantitative risk assessments.
Abnormal small bowel permeability and duodenitis in recurrent abdominal pain. Thirty nine children with recurrent abdominal pain aged between 5.5 and 12 years, underwent endoscopic duodenal biopsy to find out if there were any duodenal inflammatory changes, and if there was a relationship between duodenal inflammation and intestinal permeability to 51Cr-EDTA. Duodenal inflammation was graded by the duodenitis scale of Whitehead et al (grade 0, 1, 2, and 3). In 13 out of 39 patients (33%) definite signs of inflammation were found (grade 2 and 3). Intestinal permeability to 51Cr-EDTA in patients with duodenitis (grade 1, 2, and 3) was significantly higher (4.42 (1.73)%) than in patients with normal (grade 0) duodenal biopsy appearances (3.3 (0.9)%). A significant association was found between duodenal inflammation and abnormal intestinal permeability. Our results give further evidence that there is an intestinal origin of these patients' complaints.
Clinical evaluation of closed-loop control of blood pressure in seriously ill patients. OBJECTIVE: To compare the effectiveness of a new method of closed-loop (automatic) control of BP with usual manual control. DESIGN: Within-subject crossover trial. SETTING: General and open heart ICUs in a university teaching hospital. PATIENTS: Convenience sample of 74 seriously ill patients aged 17 to 88 yr. Twenty had hypertension: postoperative (n = 7), neurologic damage (n = 6), miscellaneous (n = 7), and were prescribed nitroprusside (n = 11) or nitroglycerin (n = 9). Fifty-four had hypotension: septic (n = 33), other (n = 21), and were prescribed norepinephrine (n = 30), dopamine (n = 11), epinephrine (n = 8), or dobutamine (n = 5). An additional 21 trials were omitted from analysis because of technical (n = 7), clinical (n = 1), or drug-related problems (n = 13). INTERVENTION: Closed-loop and manual drug administrations 1-hr were studied during periods in each patient. The target and observed mean arterial pressure (MAP) and drug infusion rate were recorded electronically every 30 sec. MAIN OUTCOME MEASUREMENTS: Time taken to achieve initial control (min); fidelity of control (the integral of size and duration of error from target MAP +/- 10% in mm Hg.hr/hr); and average drug dose administered (microgram/min as % maximum possible per drug). RESULTS: Compared with manual control, closed-loop achieved faster initial control (log-rank chi 1 = 5.04, p less than .05) and greater fidelity (mean 1.37 vs. 2.36; F = 7.15, p less than .01). There was no difference in average drug dose administered. There was uniformity in the efficacy advantage of closed-loop drug administration across drugs and patient classifications. CONCLUSION: The new closed-loop system is more effective than the usual manual control in managing acute BP disturbances in the seriously ill patient.
Hemodynamic and oxygen transport changes following endotracheal suctioning in trauma patients. Hemodynamic and oxygen transport responses to four preoxygenation techniques prior to endotracheal suctioning (ETS) were evaluated in 24 critically ill trauma patients with no preexisting lung disease. A within-subjects, repeated measures design was used. All patients had functional arterial and pulmonary artery catheters and were ventilated with a Puritan-Bennett 7200 which could immediately deliver a fraction of inspired oxygen (FIO2) of 1.0. Six breaths of maintenance FIO2 and hyperinflation without hyperoxygenation caused a fall in tissue oxygen delivery as measured by continuous transcutaneous oximetry (PtcO2). The largest increases in PtcO2 and arterial oxygen tension were seen with hyperoxygenation alone and a combination of hyperoxygenation and hyperinflation. No significant changes were found in hemodynamic (cardiac index, mean arterial pressure, mean pulmonary artery pressure, pulmonary capillary wedge pressure, systemic vascular resistance, pulmonary vascular resistance) or oxygen transport variables (oxygen delivery, oxygen extraction, oxygen consumption) 5 minutes postsuctioning. During both hyperinflation protocols, patients experienced dyspnea. It was concluded that three hyperoxygenation breaths before ETS, using a clinically feasible protocol, are adequate in preventing postsuction hypoxemia in young, hemodynamically stable trauma patients. Large volumes of hyperinflation, although found to increase PtcO2, are not advocated because of demonstrated patient discomfort and the possibility of barotrauma.
1990 ARRS Executive Council Award. Intravascular sonography in the detection of arteriosclerosis and evaluation of vascular interventional procedures. The purpose of this study was to evaluate the use of intravascular sonography for the detection of arteriosclerosis and to determine the effects of vascular interventional procedures on the arterial wall. A catheter-based 20-MHz transducer was used. Forty patients were studied. Twelve had clinical evidence of peripheral vascular disease, 13 were healthy renal donors, and 15 underwent vascular interventional procedures. The aorta and the ipsilateral iliac artery were examined in real time under fluoroscopic guidance and the results were compared with angiography. Sonography in eight of the 13 renal donors showed arterial wall abnormalities in the absence of angiographic evidence of disease. Sonography of the 15 patients after angioplasty or atherectomy demonstrated plaque fractures, intramural dissections, or atherectomy grooves. Our experience suggests that intravascular sonography is of value in reducing the use of angiography to monitor progress or complications of vascular interventional procedures.
Bilateral episodic mydriasis as a migraine equivalent in childhood: a case report. We report a 14-year-old girl who presented with yearly attacks of bilateral internal ophthalmoplegia, nausea and headache, since the age of nine. The episodic isolated bilateral mydriasis in this child is believed to be a migraine equivalent.