Melricflash/CW_MedAbstractsAlt huggingface dataset:
Bone mineral loss in young women with amenorrhoea. OBJECTIVE--To examine the impact of amenorrhoea on bone mineral density in women of reproductive age. DESIGN--Cross sectional study of 200 amenorrhoeic women compared with normally menstruating controls. SETTING--Teaching hospital outpatient clinic specialising in reproductive medicine. SUBJECTS--200 Women aged 16-40 with a past or current history of amenorrhoea from various causes and of a median duration of three years, and a control group of 57 age matched normal volunteers with no history of menstrual disorder. MAIN OUTCOME MEASURE--Bone mineral density in the lumbar spine (L1-L4) as measured by dual energy x ray absorptiometry. RESULTS--The amenorrhoeic group showed a mean reduction in bone mineral density of 15% (95% confidence interval 12% to 18%) as compared with controls (mean bone mineral density 0.89 (SD 0.12) g/cm2 v 1.05 (0.09) g/cm2 in controls). Bone loss was related to the duration of amenorrhoea and the severity of oestrogen deficiency rather than to the underlying diagnosis. Patients with a history of fracture had significantly lower bone density than those without a history of fracture. Ten patients had suffered an apparently atraumatic fracture. CONCLUSIONS--Amenorrhoea in young women should be investigated and treated to prevent bone mineral loss. Menopausal women with a past history of amenorrhoea should be considered to be at high risk of osteoporosis. 

Category: general pathological conditions
Emergency tracheal intubation in the postanesthesia care unit: physician error or patient disease? Inadequate airway maintenance has been a major factor in perioperative morbidity. To determine the incidence and etiology of emergency tracheal intubations in the postanesthesia care unit (PACU), we retrospectively reviewed 13,593 consecutive admissions to our PACU from October 1986 through October 1988. Twenty-six patients (26/13,593 = 0.19%) required the insertion of an endotracheal tube while in the PACU. Seventy-seven percent (20/26) of the intubations occurred within 1 h of extubation and/or admission to the PACU. Intubation was more common at the extremes of age; 54% of those intubated were more than 60 yr old (P = 0.003); 19% were less than 3 yr old (P less than 0.05). Twenty-three percent of the intubated patients had undergone otolaryngologic procedures (P = 0.008). Interestingly, 73% of the intubations occurred during the months of January through June (P = 0.016). Median PACU admission scores were lower for the intubated group (P less than 0.001). There was no association between intubation and gender (P = 0.74), anesthetic technique (P = 0.41), or anesthetic agent (P = 0.49). Of the 26 intubations, 18 (69%) were considered to be directly related to anesthetic management. Despite the extremely low incidence of emergency tracheal intubation in a heterogeneous group of patients admitted to our PACU, preventable anesthesia-related etiologic factors including excessive sedative or anesthetic effect, inappropriate fluid management, persistent muscle relaxant effect, and upper airway obstruction contributed to the majority of these intubations. 

Category: general pathological conditions
The effect of intravenous fixed-dose heparin during total hip arthroplasty on the incidence of deep-vein thrombosis. A randomized, double-blind trial in patients operated on with epidural anesthesia and controlled hypotension. Heparin was given in fixed doses intravenously during unilateral primary total hip-replacement operations in a prospective, double-blind trial to assess the effect on the incidence of deep-vein thrombosis. One hundred and fifty patients were randomly assigned to one of two groups before the operation. Twenty-four patients were excluded from the study, leaving 126 patients. Group I consisted of sixty-six patients who received saline solution intravenously, and Group II comprised sixty patients who received heparin. All patients had epidural anesthesia with controlled hypotension. Fixed doses of heparin were administered five minutes before the operative incision was made and every thirty minutes throughout the operation. Mean arterial pressures were maintained at between fifty and sixty millimeters of mercury in all patients. Ascending venography was done on the seventh day after the operation. The incidence of deep-vein thrombosis was 24 per cent (sixteen of sixty-six patients) in Group I and 8 per cent (five of sixty patients) in Group II; the difference is significant (p = 0.03). The intraoperative loss of blood averaged 220 +/- 79 milliliters in Group I compared with 269 +/- 109 milliliters in Group II. An average of less than one unit of blood was transfused for each patient in each group. Postoperatively, there was no difference between the groups with regard to the amount of drainage that was collected in a Hemovac device or the values for hematocrit. 

Category: cardiovascular diseases
Esophageal and gastric endoscopy in critically ill patients. How can it help you? Bleeding from the upper gastrointestinal tract in a critically ill patient is a tough diagnostic situation. Endoscopy can help physicians determine the cause of bleeding and can also provide several therapeutic options. The authors discuss these applications of the current technology. 

Category: general pathological conditions
Recreational sun exposure in Puerto Rico: trends and cancer risk awareness. Persons who sunbathe or engage in other activities at the beach are exposed to large amounts of UV radiation. Four hundred seven adults who visited the beaches of Puerto Rico were surveyed to determine their knowledge about the risks of sun exposure and to evaluate sunscreen use. The group consisted of 195 year-round Puerto Rican residents and 212 tourists. Ninety-five percent believed that the sun can cause skin cancer, although only half of the subset who lived all year in Puerto Rico believed that they personally received enough exposure to be at risk. The majority of the group (83%) understood the meaning of the sun protection factor numbers, although 35% used either nothing or a nonscreening oil. Half of Puerto Rican residents rarely or never used sunscreen protection while sunbathing. When sunscreen was used, the most important factor sought was given as sun protection factor (64%), followed by a perceived ability to aid in tanning (26%). 

Category: neoplasms
Possible role of leukotrienes in gastritis associated with Campylobacter pylori. This study was done to evaluate the role of leukotrienes (LTs) in gastritis associated with Campylobacter pylori. Biopsy specimens of gastric mucosa were obtained endoscopically from 18 patients with nonulcer dyspepsia for bacteriological and histological examination and extraction of LTs. There was correlation between the LTB4 level in the mucosa and the degree of gastritis evaluated histologically. The level was higher when infiltration of neutrophils in the gastric mucosa was more extensive. The LTB4 level in mucosa infected with C. pylori was higher than that in noninfected mucosa. These findings suggest that endogenous LTs may be related to the pathogenesis of gastritis associated with C. pylori. 

Category: digestive system diseases
L-tryptophan use and the eosinophilia-myalgia syndrome. We present a case of the eosinophilia-myalgia syndrome in a patient taking large doses of L-tryptophan for sedation. He developed the now-classic findings of myalgias, skin changes, and marked eosinophilia. This syndrome was first recognized in late 1989, and epidemiologic studies have demonstrated an association of the clinical syndrome with ingestion of L-tryptophan. The mechanism of toxicity remains unknown. Casual use of L-tryptophan has been diminished by its rapid removal from the nutrition counter of health food stores. 

Category: general pathological conditions
Onset of induced atrial flutter in the canine pericarditis model To test the hypothesis that induced atrial flutter evolves from a transitional rhythm, the onset of 99 episodes of induced atrial flutter (mean cycle length 135 +/- 18 ms) lasting greater than 5 min in 40 dogs with sterile pericarditis was first characterized. In 85 (86%) of the 99 episodes, atrial flutter was preceded by a brief period (mean 1.4 +/- 0.9 s, range 0.4 to 42) of atrial fibrillation. Then, in 11 open chest studies, atrial electrograms were recorded simultaneously from 95 pairs of right atrial electrodes during the onset of 18 episodes of induced atrial flutter (mean cycle length 136 +/- 16 ms). Atrial flutter was induced by a train of eight paced atrial beats, followed by one or two premature atrial beats (7 episodes) or rapid atrial pacing (11 episodes). A short period of atrial fibrillation (mean cycle length 110 +/- 7 ms) induced by atrial pacing activated the right atrium through wave fronts, which produced a localized area of slow conduction. Then unidirectional conduction block of the wave front occurred for one beat in all or a portion of the area of slow conduction. This permitted the unblocked wave front to turn around an area of functional block and return through the area of slow conduction that had developed the unidirectional conduction block, thereby initiating the reentrant circuit. The location of the unidirectional block relative to the direction of the circulating wave fronts determined whether the circus movement was clockwise or counterclockwise. The area of slow conduction and unidirectional conduction block occurred where the wave front crossed perpendicular to the orientation of the atrial muscle fibers, suggesting a role for anisotropic conduction. These areas included the high right atrial portion of the sulcus terminalis (10 episodes), the low right atrial portion of the sulcus terminalis (4 episodes) and the pectinate muscle region (4 episodes). It is concluded that the development of a localized area of slow conduction in the right atrium followed by unidirectional conduction block in this area produced during a short period of atrial fibrillation or rapid atrial pacing is necessary for atrial flutter to occur in this model. 

Category: cardiovascular diseases
Intravenous and oral corticosteroids for the prevention of relapse after treatment of decompensated COPD. Effect on patients with a history of multiple relapses To determine if a regimen of intravenous and oral corticosteroids reduces the relapse rate after treatment of decompensated COPD in the ED, 30 patients were studied. Forty-five visits in which intravenous and oral corticosteroids were given (T visits) were compared with an equal number of matched visits in which they were withheld (N visits). No differences were noted between T and N visits with respect to clinical findings, laboratory results and other forms of therapy. Treatment with corticosteroids reduced the relapse rate within 24 h of discharge. At 48 h, the cumulative relapse rate for T visits (8.9 percent) was significantly lower than for N visits (33.3 percent; p = 0.005). For patients with a history of multiple relapses, a regimen consisting of intravenous and oral corticosteroids reduces the risk of relapse after ED treatment of decompensated COPD. 

Category: general pathological conditions
Pressure measurements from biliary and pancreatic segments of sphincter of Oddi. Comparison between patients with functional abdominal pain, biliary, or pancreatic disease. Using a minimally compliant infusion system and a triple-lumen pressure recording catheter, we obtained endoscopic manometric measurements from both the common bile duct and pancreatic duct segments of the sphincter of Oddi (SO) in 58 patients. Fifteen patients (ages 27-69) had the diagnosis of functional abdominal pain, 19 patients (ages 30-76) had partial biliary obstruction, and 24 patients (ages 15-80) had idiopathic acute recurrent pancreatitis. Resting ductal pressure was similar in the common bile duct and pancreatic duct in all patient groups. In the group with functional pain, basal SO pressure was similar, whether obtained from the common bile duct or pancreatic duct sphincteric segment. Eight of 19 patients with partial biliary obstruction had elevated basal SO pressure. Five of these eight patients had elevated basal SO pressure confined exclusively to the common bile duct segment of the sphincter, while three patients had elevated basal SO in both segments. Conversely seven of 24 patients with acute recurrent pancreatitis had an elevated basal SO pressure, with five patients having pressure elevation only in the pancreatic duct segment while two patients had abnormal basal SO pressure in both segments. We conclude that selective cannulation of the common bile duct and/or the pancreatic duct during manometric study of the SO is necessary in order to diagnose segmental SO dysfunction responsible for partial biliary obstruction or episodes of acute recurrent pancreatitis. 

Category: general pathological conditions
Maple syrup urine disease caused by a partial deletion in the inner E2 core domain of the branched chain alpha-keto acid dehydrogenase complex due to aberrant splicing. A single base deletion at a 5'-splice donor site of an intron of the E2 gene disrupts the consensus sequence in this region. We have studied the molecular bases of maple syrup urine disease by analyzing the activity, subunit structure, mRNA sequence, and the genome of the affected enzyme. The branched chain alpha-keto acid dehydrogenase (BCKDH) activity in the patient was 4.2-4.5% of the control level. Immunoblot analysis revealed that the E2 subunit of BCKDH (Mr 52,000) was absent and another protein band with an Mr of 49,000 was present. We amplified the cDNA of the E2 subunit obtained from the patient's cell using the polymerase chain reaction method, then sequenced the amplified cDNA, in which a 78-bp deletion was identified. The consanguineous parents and a sister had two species of mRNA; the one corresponding to the normal E2 subunit and the other with a 78-bp deletion, whereas findings in a brother were normal. The molecular size of the translation products as deduced from the abnormal mRNA sequence was compatible with an abnormal protein band (Mr 49,000) detected in the patient's cells by immunoblot analysis. Analysis of genomic DNA of BCKDH-E2 subunit revealed that the 78-bp deletion in the mRNA was caused by an exon skipping due to a single base deletion in the 5'-splice donor site. As a result of the mutation, part of the inner E2 core domain was omitted. The specified region of the inner E2 core domain was highly homologous to the region of the E2 subunit of pyruvate dehydrogenase and alpha-ketoglutarate dehydrogenase. These observations imply the biological importance of the region in the inner E2 core domain of BCKDH to maintain normal function of the activity. 

Category: general pathological conditions
Primary carcinoma of the upper urinary tract. Effect of primary and secondary therapy on survival. The pathologic material and medical records of 76 patients with primary upper urinary tract carcinomas were reviewed to identify the role of grade and stage in predicting survival; to determine any differences in survival between ureteral and renal pelvic carcinoma; to understand the role of local therapy in low grade, low stage tumors; and to establish the usefulness of adjuvant therapies in metastatic disease. Kaplan-Meier survival curves with Cox-Mantel analysis for statistical significance revealed both grade and stage to be excellent predictors of survival. No differences in survival were noted between renal pelvic and ureteral carcinomas for equivalent stage tumors. For low grade, low stage tumors, although there was an increased risk of local recurrence with local therapy, there were no differences in survival between patients treated with local therapy or radical surgery. Finally, cisplatin-based chemotherapy seemed to improve survival in patients with metastatic disease. 

Category: neoplasms
Use of computed tomographic scanning and aortography in the diagnosis of acute dissection of the thoracic aorta. Before the introduction of computed tomographic (CT) scanning, aortography was the investigation of choice for acute aortic dissection. Between 1978 and 1982, 24 patients were referred to the Brompton Hospital with suspected acute thoracic aortic dissection; all had aortography with diagnosis confirmed at surgery (n = 12) or necropsy (n = 2) or supported by clinical outcome (n = 8). One patient in whom aortography was negative had type B dissection at necropsy and another patient was lost to follow up. CT scanning became available in this unit in 1983 and between 1983 and 1987 was used as the only imaging investigation in 32 patients with suspected acute dissection of the thoracic aorta while in a further 22 patients aortography was used alone. Results were confirmed at surgery (n = 18), necropsy (n = 3), or supported by clinical outcome (n = 31). Two patients were lost to follow up. In an additional 16 patients both aortography and CT scanning were performed with concordant findings in 10. In six in whom the results were discordant, aortography was normal in three in whom subsequent CT scanning showed type B dissection and CT scanning was normal in three patients in whom aortography showed type A dissection. Both CT scanning and aortography are reliable techniques for assessment of suspected acute dissection of the thoracic aorta. Both techniques misdiagnose occasionally and the frequency of misdiagnosis will be minimised by performing both investigations in patients where the level of clinical suspicion is high and the initial investigation negative. CT scanning tends to miss type A dissection and in view of the success of surgery in this condition this failing has the more serious clinical consequences. 

Category: cardiovascular diseases
A risk-benefit analysis of elective bilateral oophorectomy: effect of changes in compliance with estrogen therapy on outcome. A bilateral oophorectomy at the time of elective hysterectomy is often performed to prevent ovarian cancer. The assumption that endogenous estrogen can be easily replaced with supplemental medication fosters the decision for routine oophorectomy. Published reports on the use of postmenopausal estrogen indicate that compliance is less than perfect. This fact could affect the overall outcome. Decision analysis techniques with Markov cohort modeling were used to evaluate the policy of elective bilateral oophorectomy. Results from studies judged methodologically sound were combined to determine values representing the influence of estrogen on coronary heart disease, breast cancer, and osteoporotic fracture. The decision tree also explicitly incorporated patient compliance. When compliance with estrogen therapy is assumed to be perfect, oophorectomy yields longer life expectancy than retaining the ovaries. When actual drug-taking behavior is considered, retaining the ovaries results in longer survival. This analysis highlights the importance of including the effects of patient compliance with treatment recommendations when the impact of a health policy decision such as prophylactic surgery is assessed. 

Category: cardiovascular diseases
Impact of echocardiography on the management of patients with mitral valve prolapse OBJECTIVE: To determine whether echocardiography affects the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients suspected of having mitral valve prolapse (MVP). DESIGN: Retrospective review of echocardiograms and clinical records. SETTING: Military tertiary care hospital. PATIENTS: 127 patients with clinically suspected MVP (105) or incidentally discovered MVP (22). MAIN RESULTS: Beta blockers were used more often in patients with suspected MVP and positive echocardiograms (45%) than in patients with normal echocardiograms (13%, p less than 0.001). Bacterial endocarditis prophylaxis was recommended more often in patients with suspected MVP and positive echocardiograms (65%) than in patients with normal echocardiograms (11%, p less than 0.001). Presence or absence of a murmur did not influence the decision to recommend bacterial endocarditis prophylaxis. Patients in whom MVP was incidentally discovered were unlikely to receive either beta blockers or the recommendation for bacterial endocarditis prophylaxis. CONCLUSIONS: The results of echocardiography affect the decisions to use beta blockers or to recommend bacterial endocarditis prophylaxis in patients with suspected MVP. 

Category: general pathological conditions
The surprising kidney-fluid mechanism for pressure control--its infinite gain! In this short paper, I have tried to explain the elation that we felt when we first realized that the kidney-fluid mechanism for controlling the arterial pressure has an infinite feedback gain property. Because of this, all the other pressure control mechanisms, none of which has ever been shown to have a similar infinite gain property, must themselves alter the kidney-fluid mechanism if they are to succeed in causing long-term changes in the arterial pressure. We have not been able to refute this principle despite many experiments over the last 2 decades. For this reason, our first understanding of the infinite gain property of the kidney-fluid mechanism was like a light at the end of the tunnel. I hope that I can explain to the reader the excitement of those few seconds when we first recognized the principle in 1966. 

Category: cardiovascular diseases
A single cholesterol measurement underestimates the risk of coronary heart disease. An empirical example from the Lipid Research Clinics Mortality Follow-up Study. In prospective epidemiologic studies of coronary heart disease, a single measurement of cholesterol is made to assess its relationship to the risk of coronary disease. Statistical theory states that if this measurement is subject to within-individual variability, the strength of the relationship will be underestimated. This is empirically shown for the example of plasma cholesterol. For the Lipid Research Clinics Follow-up Study population (comprising 2170 white men over 30 years of age), the age-adjusted coronary heart disease mortality regression coefficient increases from .453 to .496 if the average of two cholesterol measurements is used instead of a single measurement. Since the correlation between the two repeated cholesterol measurements is .815, an increase in the regression coefficient up to .556 would be expected if the true cholesterol values were available. Thus, epidemiologic studies have substantially underestimated the strength of the relationship between cholesterol levels and the risk of coronary disease by calculating the relationship on the basis of a single cholesterol determination. 

Category: cardiovascular diseases
Crohn's disease: what about the pancreas? [editorial] Crohn's disease (CD) is now accepted as a systemic illness. The importance of extraintestinal manifestations is underlined by the fact that such "complications" can be more prominent and even more difficult to control than the intestinal disease itself. Lately, evidence for a more than accidental association of pancreatitis and exocrine pancreatic insufficiency with CD is growing. This might have a significant impact on the treatment of abdominal pain and diarrhea in CD, symptoms which have so far been attributed exclusively to the intestinal rather than the extraintestinal manifestations of the disease. 

Category: digestive system diseases