Melricflash/CW_MedAbstractsAlt huggingface dataset:
Oxygen uptake and heart rate responses during hypoxic exercise in children and adults. Control of ventilation and heart rate during exercise appears to undergo maturation, while aerobic metabolism (VO2) may not. Since we had previously found that hypoxia during exercise produced different ventilatory responses in children (C) compared to adults (A), we hypothesized that VO2 and heart rate kinetics during exercise would show similar maturational responses to hypoxia. To test this hypothesis, we examined the responses during progressive (ramp) and constant work rate tests in children and adults breathing either room air or hypoxic gas (FiO2 = 0.15). When corrected for body weight, children and adults had similar values for lactic acidosis threshold (LAT) (C: 29.1 +/- 5.0 ml.min-1.kg-1; A: 27.9 +/- 4.3) and VO2max (C: 40.7 +/- 8.6 ml.min-1.kg-1; A: 45.2 +/- 6.7) during normoxia. Hypoxia significantly lowered LAT (C: 27.5 +/- 5.4 ml.min-1.kg-1; A: 23.2 +/- 3.8; both P less than 0.05) and VO2max (C: 37.7 +/- 8.3 ml.min-1.kg-1; A: 40.1 +/- 5.3; both P less than 0.05) in both children and adults. Metabolic efficiency (delta VO2/delta work rate) and the VO2-heart rate relationship (delta VO2/delta HR/kg) were similar in the two groups and unaffected by hypoxia. During the constant work rate exercise, VO2 kinetics (time constant during phase 2 of the response (pi 1) and the O2 deficit) were similar between children and adults and were significantly slowed by hypoxia, consistent with current understanding of the control of oxidative metabolism. Finally, heart rate was increased at rest and during exercise with hypoxia, while the time to reach 75% of the end-exercise response was delayed significantly, in both groups. 

Category: general pathological conditions
Cholangiocarcinoma in association with multiple biliary microhamartomas. The rarity of cholangiocarcinoma occurring in von Meyenburg complexes is well appreciated. We describe the case of a 35-year-old man found to have cholangiocarcinoma in association with multiple biliary microhamartomas of the liver. Areas of ductal proliferation and atypia within the bile duct hamartomas suggest malignant transformation to cholangiocarcinoma. 

Category: neoplasms
Local-regional breast cancer recurrence following mastectomy. Local-regional recurrence patterns were investigated in 1392 patients with breast cancer. Primary treatment for all patients included a mastectomy. Nine hundred seventeen patients had negative nodes and did not receive systemic therapy. Four hundred seventy-five patients had node metastases and were randomized to receive different combinations of chemoendocrine therapy. Follow-up ranged between 5 and 16 years. Two hundred thirty (25.8%) node-negative patients have had recurrences, with the initial recurrence being local-regional in 9.2%. Two hundred forty-two (50.9%) node-positive patients have had recurrences, with the initial recurrence being local-regional in 17.1%. Larger tumors and more extensive node involvement were associated with more first local-regional recurrences. The relative percent of first local-regional recurrence among patients in whom cancer recurred was similar for node-negative and node-positive patients (35.4% and 33.5%, respectively). In 63.6% of patients in whom cancer recurred, first local-regional recurrence were distant. Larger tumors, more extensive node involvement, and a shorter disease-free interval after mastectomy were associated with more rapid appearance of distant recurrence among these patients. 

Category: neoplasms
Chromogranin A: posttranslational modifications in secretory granules. The primary structure of chromogranin A indicates multiple domains which might be subject to posttranslational modification. We explored chromogranin A's proteolytic cleavage, glycosylation, and possible intermolecular disulfide links, using biochemical and cell biological approaches. Anti-chromogranin A region-specific immunoblots on chromaffin granules suggested bidirectional endoproteolytic cleavage of chromogranin A; control experiments ruled out artifactual cleavage during granule isolation or lysis. Isolation of chromogranin A-derived peptides by gel filtration chromatography or sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), followed by N-terminal amino acid sequencing, established several cleavage sites, including at least two at dibasic sites. Secretion of chromogranin A from bovine chromaffin cells did not initiate further cleavage, nor did prolonged exposure of secreted chromogranins to the secretory cells. The chromogranin A cleavage pattern was qualitatively similar in other neuroendocrine tissues, though cleavage was more complete in adrenal medullary than in anterior pituitary hormone storage vesicles, and N-terminal fragments of 45 and 55 kilodaltons were more prominent in the hypothalamus. A similar cleavage pattern was seen in human pheochromocytoma granules, as judged by chromogranin A region-specific immunoblots, fragment isolation by SDS-PAGE, and microsequencing. The presence of full-length chromogranin A as the core protein of a chromaffin granule soluble proteoglycan was suggested in bovine (but not human) chromaffin granules by glycoprotein staining, chondroitinase ABC digestion, chemical deglycosylation, and region-specific immunoblotting. Human (but not bovine) chromogranin A displayed intermolecular disulfide crosslinks on SDS-PAGE gels and immunoblotting. These results document diverse structural paths that the chromogranin A molecule may take in endocrine secretory cells after its translation. 

Category: neoplasms
Study of preneoplastic changes of liver cells by immunohistochemical and molecular hybridization techniques. The status of hepatitis B virus DNA was investigated by in situ hybridization in multifocal areas of a noncancerous hepatitis B virus-associated cirrhosis. This liver exhibited a marked degree of dysplasia and adenomatous hyperplasia. The results of these studies were correlated with the histopathology and immunohistochemical stains for hepatitis B core and surface antigens. There was clear evidence of a marked reduction to absence of hepatitis B viral DNA by in situ hybridization and absence of HBc and HBsAg in the foci of liver cell dysplasia and adenomatous hyperplasia. These results support the hypothesis that liver cell dysplasia and adenomatous hyperplasia are preneoplastic in nature. 

Category: neoplasms
Ocular motor abnormalities from head trauma. Head injuries cause the hospitalization of 200-300 persons per 100,000 population per year. Ophthalmologists provide diagnostic and therapeutic care to those trauma victims with damage to the globe, optic nerve, orbit, and ocular motor system. Eye movements can be affected by damage at any level of the central nervous system or peripheral motor unit. Comprehensive ocular motor assessment of the trauma patient can substantially contribute to the understanding of the patient's injury, recovery, and rehabilitation. This review examines all aspects of head and face trauma that can lead to ocular motility disturbances. 

Category: nervous system diseases
Staging and follow-up of breast cancer patients. Staging systems for breast cancer, unlike those of neoplasms in distant or recessed sites, allowed for the early development of clinical staging evaluation. It was established that clinical assessment of the breast lesion was often wrong compared with the pathologic examination (benign vs. malignant); clinical measurement of the tumor in centimeters was often larger than histologic size; and clinical assessment of axillary nodes (clear or metastatic) was incorrect in about 30% of cases. Although both clinical and pathologic staging provide effective discriminants for prognosis of treated patients, prognosis is more accurately determined by the pathologic stage. The single most important prognostic indicator is the axillary nodal status, and when positive, the number of positive nodes. The American Joint Committee on Cancer and the Union International Contra Cancer have agreed on a TNM staging for breast carcinoma, and this is the preferable staging system. Follow-up of treated patients is of most value in detecting local recurrence on the chest wall (after mastectomy) or in the irradiated breast (after lumpectomy), and also in early detection of contralateral breast cancer. Physical examination and periodic mammography are most useful. There is a tendency to overinvestigate asymptomatic patients (with bone scans, blood tests, etc.), but this has been correctly criticized in recent years. 

Category: neoplasms
Opioids in cerebrospinal fluid in hypotensive newborn pigs. This study was designed to determine if opioids were detectable in cerebrospinal fluid (CSF) and if these concentrations were altered by hemorrhagic hypotension. This study was further designed to determine the effects of topically administered opioids on pial arteriolar diameter during normotension and hypotension. Closed cranial windows were used to determine pial arteriolar diameter. Periarachnoid cortical and cisterna magna CSF was collected from piglets during normotension and hypotension (systemic arterial pressure decreased from 63 +/- 1 to 33 +/- 1 mm Hg). Opioid profiles were assessed qualitatively by radioreceptor assay, and individual opioids were measured quantitatively by radioimmunoassay. Periarachnoid cortical and cisterna magna CSF methionine enkephalin-, leucine enkephalin-, dynorphin-, and beta-endorphin-like receptor active values all were increased by hypotension. When quantified by radioimmunoassay, periarachnoid cortical CSF values for methionine enkephalin-like immunoreactivity were 1,167 +/- 58 and 2,975 +/- 139 pg/ml for normotension and hypotension, respectively. Periarachnoid cortical CSF radioimmunoassay values for dynorphin-like immunoreactivity were 15 +/- 2 and 28 +/- 2 pg/ml for normotension and hypotension, respectively. When applied topically to the cortical surface, synthetic methionine enkephalin increased pial arteriolar diameter (134 +/- 4, 158 +/- 4, and 163 +/- 4 microns for control, 574 pg/ml [10(-10) M], and 5,740 pg/ml [10(-9) M], respectively). Similarly, topical synthetic leucine enkephalin and dynorphin elicited pial arteriolar dilation. However, beta-endorphin produced arteriolar constriction. Hypotension attenuated methionine and leucine enkephalin-induced dilation and reversed dynorphin-induced dilation to concentration-dependent constriction. beta-Endorphin-induced constriction was not changed by hypotension. Therefore, opioids could contribute to the control of the cerebral circulation during hypotension. 

Category: general pathological conditions
Transferrin receptor activity as a marker in transitional cell carcinoma of the bladder. An immunohistochemical staining method was used to study transferrin receptors (TFR) in bladder tissue from 10 patients with benign conditions and 33 with bladder cancer. All patients with bladder cancer were followed up by cystoscopy at intervals of 3 months (mean follow-up period 11 months). The relationship between TFR activity and recurrence rates was investigated. It was not possible to demonstrate TFR in normal bladder mucosa except for the proliferating cells of the basal layer. TFR activity in malignant tissue correlated well with the histological grade and pathological stage of the tumour. Patients with low grade superficial tumours showing TFR activity had a higher recurrence rate than those with no TFR activity. It was concluded that TFR activity in low grade superficial bladder tumours is a useful marker for predicting the recurrence rate. 

Category: neoplasms
Aspiration biopsy cytology of occult breast lesions by use of the "scouting needle". A prospective study of 261 cases. The increased use of mammography for the detection of impalpable breast lesions has resulted in a need for new diagnostic techniques. In a prospective study of 261 occult breast lesions, aspiration biopsy was done with a standard fine needle and syringe. This "scouting needle" technique permits the collection of diagnostic cytologic material in the clinician's office without specialized radiologic equipment. Thirty of 53 malignant lesions (57%) were detected cytologically. A benign cytologic diagnosis, which was made in 220 patients, did not preclude additional investigation. Aspiration biopsy using the "scouting needle" is a rapid, low-cost, easily performed, initial procedure which complements "watchful waiting." When diagnostic of carcinoma, it results in immediate surgical intervention and may obviate two-stage surgical treatment. 

Category: neoplasms
Coarctation of the aorta. Coarctation of the aorta is a common cardiovascular disorder with an unknown etiology. In the preductal type, blood flows from a patent ductus into the distal aorta. When the coarctation is juxtaductal or postductal, blood flows to the lower extremities by way of the subclavian arteries and collaterals. Plain films may show the reverse sign in postductal coarctation. Arteriography is the gold standard for making the diagnosis. However, magnetic resonance imaging will probably become an increasingly important diagnostic tool. The treatment of choice is surgery, with complete resection of the stenosed segment. 

Category: cardiovascular diseases
Mechanisms of vein graft atherosclerosis: LDL metabolism and endothelial actin reorganization. We have explored the effect of arterial hemodynamics on endothelial cell morphology and low-density lipoprotein metabolism in human saphenous vein segments harvested from tissue donors. An arterial pulsatile perfusion system was used to impose physiologic pressures and flows for 20 hours on saphenous vein and companion (control) femoral artery segments. A venous perfusion apparatus was also employed for the perfusion of a second (control) saphenous vein segment for the same period of time. Calculations of fluid shearing and wall tensile stresses were performed and related to induced changes in endothelial cell geometry and cytoskeletal actin organization and the incorporation, degradation, and localization of intact low-density lipoprotein within the vessel wall. Our results indicate that, compared with native arteries and veins, a 20-hour exposure of test saphenous veins to arterial hemodynamics induced (1) a significant increase in endothelial cell luminal surface area and perimeter independent of alignment with flow, (2) disassembly of the dense peripheral band of actin with a concomitant assembly of stress fibers, and (3) a two- to fourfold elevation in the undegraded low-density lipoprotein content, localized primarily within the subendothelial intima. Although the exact mechanisms underlying these results are uncertain, the focal accumulation of intramural low-density lipoprotein may be related to the loss of normal barrier function during endothelial cell enlargement, which is accompanied by transient cytoskeletal reorganization during the adaptation to arterial flow. 

Category: general pathological conditions
Epitope mapping of human thyroglobulin. Heterogeneous recognition by thyroid pathologic sera. Thyroglobulin is the major Ag of the thyroid gland involved in autoimmune pathologies. Epitope mapping was carried out with a rabbit polyclonal immune serum against fusion proteins expressed in prokaryotic cells. After screening of an initial human thyroglobulin cDNA library and subcloning of immunoreactive clones, seven epitopes were characterized and localized on the human thyroglobulin monomeric molecule. One was close to each extremity of the molecule, and five others were concentrated in the middle, covering a sixth of this 2748-amino-acid chain. The immunoreactivities of 18 autoimmune sera from different thyroid pathologies were tested against the seven previously characterized epitopes. Those from Hashimoto's thyroiditis were the most immunoreactive. Immune responses were heterogeneous for sera from different pathologies as well as for those from the same pathology. The central epitopes and the near-C-terminal epitope, however, were the epitopes most often recognized by the immune sera. These findings show that some autoepitopes overlap accurately with some heteroepitopes characterized by a polyclonal immune serum directed against the mature protein. 

Category: neoplasms
Unfading acral microlivedo. A discrete marker of thrombotic skin disease associated with antiphospholipid antibody syndrome. Small erythematous or cyanotic lesions on the hands and feet of four patients with antiphospholipid antibodies are described. These discrete lesions outline capillaries and do not disappear when pressure is applied. The histologic features are identical to those described in skin thrombotic syndrome associated with antiphospholipid antibodies, that is, microthrombi in dermal vessels without inflammation. In addition to indicating antiphospholipid antibodies in apparently healthy patients, this sign could be a marker of risk for large-vessel thrombosis. 

Category: cardiovascular diseases
Capillary leakage in inflammation. A study by vascular labeling. The local injection of pure inflammatory mediators induces venular leakage. To test the effect of endogenous mediators from dying tissue on vascular leakage, the authors devised an experimental model simulating an infarct, whereby living vessels would be exposed to fragments of organs undergoing aseptic necrosis. Tissues from donor rats were implanted aseptically in the cremasteric sac. Control rats were implanted with materials deemed to be as close as possible to nonirritating: boiled tissues and spheres of Teflon or glass. At different points the rats were injected intravenously with carbon black and killed an hour later. Whole cremaster mounts showed that vascular labeling was strictly venular up to 8 hours, mixed with capillary labeling between 12 and 24 hours, and mainly or exclusively capillary at 48 hours. Histology showed an acute inflammatory infiltrate in the labeled areas. A similar but weaker labeling pattern accompanied by milder inflammation was seen in controls. These results indicate that the vascular leakage in aseptic inflammation is biphasic, first venular, then capillary; and that the capillary phase is induced by the inflammatory reaction itself, possibly through a form of diffuse angiogenesis. 

Category: general pathological conditions
Trends in basal cell carcinoma, squamous cell carcinoma, and melanoma of the skin from 1973 through 1987. Major increases have occurred in the incidence of basal cell carcinoma and squamous cell carcinoma of the skin, as well as in cutaneous malignant melanoma during the period 1973 through 1987 in British Columbia. The greatest increases in basal and squamous cell carcinomas are on the head and neck. This indicates that exposure to sunlight is the major causative factor. The greatest increase in melanoma is on the trunk in men and on the lower limbs in women. The dramatic increases in nonmelanoma skin cancers in British Columbia, a relatively low sunlight area, suggest that major prevention programs are needed in areas that are not considered "sunspots.". 

Category: neoplasms
The origin of epidermal melanocytes. Implications for the histogenesis of nevi and melanomas. Among the most venerable concepts in dermatopathology is Unna's 19th century notion of Abtropfung, ie, that melanocytes drop off from the epidermis to the dermis during the histogenesis of melanocytic tumors. Paradoxically, however, Unna's basic premise of an epidermal origin for melanocytes has been seriously questioned for over 40 years, based on experimental evidence favoring a neural crest origin for melanocytes. Recent work has strengthened the evidence for a neural crest origin of epidermal melanocytes, and it has been suggested that the concept of Abtropfung be replaced by the concept of Hochsteigerung. The concept of Hochsteigerung holds that melanocytes migrate up from the dermis into the epidermis-not only in normal development, but also during normal tissue maintenance. It now seems likely that the precursor of melanocytes, in both normal and abnormal differentiation, may not be a melanoblast (a primitive cell committed to melanocytic differentiation) but rather a pluripotential cell. Although axon-investing Schwann cells have been the traditional focus as the closest relative of the epidermal melanocyte, recent studies suggest that another nerve sheath cell, the perineural cell, might be a better candidate. These concepts have profound implications for the histogenesis of melanocytic nevi and melanomas. 

Category: general pathological conditions
Postoperative lumbar spinal instability occurring or progressing secondary to laminectomy. The manifestations and pathomechanism of postoperative lumbar spinal instability, occurring or progressing secondary to laminectomy, was clarified by means of functional radiographic analysis in a series of 46 patients over 40 years of age. The relation between instability and the clinical symptoms also is discussed. In patients under 60 years of age, instability at the operated level tended to appear in cases of wide laminectomy more often than in cases of partial laminectomy. Occurrence or progress of instability seems to be promoted by resection of the posterior spinal elements rather than the disc. It is further considered that the postoperative aggravation of clinical symptoms may be influenced not only by instability, but also by the other factors. 

Category: nervous system diseases
Interferon antibodies may negate the antiviral effects of recombinant alpha-interferon treatment in patients with chronic hepatitis B virus infection. In a randomized controlled trial of recombinant alpha-2a interferon for chronic hepatitis B, interferon antibodies developed in 21 (39%) of 54 Chinese adults who received IFN. No correlation was observed between sex, age, pretreatment serum ALT level or liver histological findings and the development of interferon antibodies. Antibodies were significantly more likely to develop in patients who received lower doses (2.5 or 5 MU/m2) of alpha-2a interferon than in those who received a higher dose (10 MU/m2): 53% vs. 11% (p = 0.006). The development of interferon antibodies appeared to reverse the initial antiviral response to treatment, with reappearance of hepatitis B virus DNA in serum in 12 patients and HBeAg in three patients. Sustained clearance of HBeAg was achieved in only one (5%) patient but was achieved in seven (21%) patients without interferon antibodies. The mere presence of interferon antibodies did not preclude an antiviral response to interferon therapy, but patients with high titer neutralizing antibodies were less likely to respond. These findings suggest that interferon antibodies may negate the antiviral effects of alpha-2a interferon. A higher incidence of interferon antibodies in Chinese vs. white patients with chronic hepatitis B may contribute to the poorer antiviral response in Chinese patients. 

Category: general pathological conditions
Lipomatous hypertrophy of the interatrial septum: an unusual intraoperative finding. Lipomatous hypertrophy of the interatrial septum was an incidental finding in a man of 45 undergoing coronary artery bypass grafting for unstable angina. He was not overweight and did not have any rhythm disturbances. The diagnosis was made on frozen section. 

Category: neoplasms
Endosalpingosis as a cause of chronic pelvic pain. Endosalpingosis, a condition characterized by ectopic oviduct epithelium, is diagnosed histologically by the appearance of benign ciliated and nonciliated columnar cells in an abnormal location. Endosalpingosis is typically without symptoms. Our unusual case report shows symptomatic endosalpingosis first seen with chronic pelvic pain. Various aspects of this disease will also be discussed. 

Category: neoplasms