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1.
BACKGROUND: Despite recognition of the high prevalence of alcoholism among patients with head and neck cancer, the prognostic importance of alcoholism has not been evaluated adequately. Previous investigators have speculated that alcoholic patients may have a poorer prognosis than nonalcoholic patients because of more advanced stage of cancer, the immunosuppressive effects of alcohol, and an increased rate of death due to other alcohol-related diseases. PURPOSE: The goal of this population-based study was to identify the features of alcoholism that are associated with survival for patients with head and neck cancer and to develop an alcoholic severity staging system from a composite of the independent features of alcoholism. METHODS: This prospective study included 649 patients who were diagnosed with cancer of the oral cavity, oropharynx, hypopharynx, or larynx during the period from September 1, 1983, through February 28, 1987, in a three-county area of western Washington state that participates in the Surveillance, Epidemiology, and End Results Program of the U.S. National Cancer Institute. Details on lifetime alcohol consumption, treatment for alcoholism, abstinence from alcohol prior to the diagnosis of cancer, and alcohol-related health problems were ascertained through in-person interviews near the time of diagnosis. Patients were classified as either nonalcoholics or alcoholics according to their responses to questions from the Michigan Alcoholism Screening Test. The measures of alcohol consumption and abuse that were found to be independently associated with 5-year survival by logistic regression analysis were combined using conjunctive consolidation to create a final composite variable, called an alcoholic severity stage. Cox proportional hazards regression analysis was done to estimate the relative risk (R) of death within 5 years due to specific causes of death for each of the alcoholic severity stages. RESULTS: Alcoholism (RR = 2.06; 95% confidence interval [CI] = 1.43-2.98) and a history of alcohol-related systemic health problems (i.e., liver disease, pancreatitis, delirium tremens, or seizures) (RR = 2.76; 95% CI = 1.69-4.49) were associated with an increased risk of death, whereas abstinence (i.e., the consumption of fewer than one drink per week at 1 year prior to the diagnosis of cancer) (RR = 0.62; 95% CI = 0.39-0.97) was associated with a decreased risk of death. These associations were independent of age, site of cancer, anatomical stage, histopathologic grade, smoking, and type of antineoplastic treatment. Patients in the two worst alcoholic severity stages had an increased risk of dying not only of head and neck cancer but also of cardiovascular disease, pulmonary disease, and other alcohol-related causes. CONCLUSIONS: Alcohol abuse, measured by alcohol consumption, functional impairment, a history of alcohol-related health problems, or abstinence, can provide important prognostic information for patients with head and neck cancer. Our results suggest that sobriety among alcoholic patients can lead to prolonged survival.  相似文献   
2.
Knee ligamentous injuries occur during sport, and when there is extensive injury, they can be associated with subluxation or dislocation. We present the case of a female basketball player who sustained a knee dislocation during noncontact play. An immediate angiogram confirmed vascular integrity, and surgical treatment with ligamentous reconstruction was performed. Peroneal nerve injury was present but resolved in 42 weeks. A review of the literature discussing knee dislocation is presented.  相似文献   
3.
Despite the strong association between protein catabolic conditions and hyperglucagonemia, and enhanced glucagon secretion by amino acids (AA), glucagon's effects on protein metabolism remain less clear than on glucose metabolism. To clearly define glucagon's catabolic effect on protein metabolism during AA load, we studied the effects of glucagon on circulating AA and protein dynamics in six healthy subjects. Five protocols were performed in each subject using somatostatin to inhibit the secretion of insulin, glucagon, and growth hormone (GH) and selectively replacing these hormones in different protocols. Total AA concentration was the highest when glucagon, insulin, and GH were low. Selective increase of glucagon levels prevented this increment in AA. Addition of high levels of insulin and GH to high glucagon had no effect on total AA levels, although branched chain AA levels declined. Glucagon mostly decreased glucogenic AA and enhanced glucose production. Endogenous leucine flux, reflecting proteolysis, decreased while leucine oxidation increased in protocols where AA were infused and these changes were unaffected by the hormones. Nonoxidative leucine flux reflecting protein synthesis was stimulated by AA, but high glucagon attenuated this effect. Addition of GH and insulin partially reversed the inhibitory effect of glucagon on protein synthesis. We conclude that glucagon is the pivotal hormone in amino acid disposal during an AA load and, by reducing the availability of AA, glucagon inhibits protein synthesis stimulated by AA. These data provide further support for a catabolic role of glucagon at physiological concentrations.  相似文献   
4.
The serum of some patients with insulin-resistant "diabetes" contains antibodies that bind to and block the cell membrane receptors for insulin. In this report, we have characterized the effects of the antireceptor antibodies on the interaction of (125)I-insulin with its receptor on the human lymphoblastoid cell line IM-9. Up to 95% of specific insulin binding can be inhibited by pretreatment of the cells with these immunoglobulins. The onset of the inhibitory effect is time- and temperature-dependent, and the effect is reversed extremely slowly if the cells are suspended in a large excess of antibody-free buffer. These features of antibody binding can be easily distinguished from those for insulin binding to its receptor. The inhibitory effect of the antibodies can be reversed by exposure of the cells to conditions known to elute surface immunoglobulins. The three antireceptor sera studied appear to alter the insulin-receptor interaction in different ways. Two antisera markedly reduce receptor affinity through combined effects on the insulin association and dissociation rates, and, additionally, have smaller effects on available receptor number. A third antiserum primarily affects available receptor number and has little effect on receptor affinity. All three antisera inhibit the capacity of insulin to promote negatively cooperative site-site interactions among insulin receptors. The data suggest that these autoantibodies to the insulin receptor bind to different determinants on the receptor and may therefore be useful as unique probes of insulin receptor structure and function.  相似文献   
5.
Individually housed DBA/2J mice were fed a liquid diet in which ethanol supplied 33% of the calories. The level of physical dependence that developed was estimated by scoring convulsions, elicited by handling the mice, after discontinuing the alcohol diet. The severity of the withdrawal reaction increased progressively with duration (5-12 days) of alcohol administration. A 2-day period on the diet produced no withdrawal reaction. Pretreatment of the mice with alcohol in their drinking water slightly increased the subsequent intake of the liquid diet. "Effective" alcohol intake was defined as uninterrupted alcohol consumption above 10 g/kg/day. Withdrawal scores correlated better with effective intake than with total intake under a variety of conditions. We interpret this to mean that brief interruptions in drinking (1 day) may allow the accrued physical dependence to disappear. On the basis of their effective alcohol intake, mice could be assigned to nondependent, moderately dependent or severely dependent groups for further study of the nature of physical dependence.  相似文献   
6.
To ascertain the temporal relationships of phcnylpropanoid and lignin pathway enzymes, phenylalanine ammonia-lyase (PAL) and cinnamyl alcohol- NADPH dehydrogenase(CAD), with lignin concentration, PAL and CAD activities and lignin concentrations were assessed during progressive development of the 10th internode in maize (Zea mays L). Enzyme activities were quantified and lignin concentrations were determined by the detergent system of fiber fractiona- tion from lower, middle, and upper sections of the elongating internode harvested 3, 5, 7, 9, 11, 13, and 15 days after the internode had reached 10 mm in length. Over 15 days, a coordinated, sequential, and basipetal pattern of enzyme activities and lignin accumulation evolved through the internode, spanning the stages of rapid elongation, cellular differentiation, and secondary cell wall formation. PAL activity was initiated first, rising to peak activity in elongating tissue, and falling basipetally in tissues as they matured. CAD activity rose in fully elongated, maturing internode tissue where PAL activity was waning following its peak activity. Lignin accumulated in tissues with high CAD activity. CAD activity and lignin deposition patterns were similar: simultaneously increasing in activity and deposition over time while activity and deposition also shifting basipetally through the internode, keeping pace with secondary cell wall formation. Lignin concentration correlated significantly with CAD, but not with PAL.  相似文献   
7.
The site of S1-S2 root activation following percutaneous high-voltage electrical (ES) and magnetic stimulation were located by analyzing the variations of the time interval from M to H soleus responses elicited by moving the stimulus point from lumbar to low thoracic levels. ES was effective in activating S1-S2 roots at their origin. However supramaximal motor root stimulation required a dorsoventral montage, the anode being a large, circular surface electrode placed ventrally, midline between the apex of the xiphoid process and the umbilicus. Responses to magnetic stimuli always resulted from the activation of a fraction of the fiber pool, sometimes limited to the low-thresholds afferent component, near its exit from the intervertebral foramina, or even more distally. Normal values for conduction velocity in motor and 1a afferent fibers in the proximal nerve tract are provided.  相似文献   
8.
To further study the relationship between resistance to apoptosis and drug resistance in harringtonine-resistant HL-60 cells (HR20), cyclosporine A (CsA) 20, 10 micrograms.ml-1 was shown to induce the sensitive HL-60 cells to apoptosis, showing a typical DNA "ladder" band. But the same concentrations of CsA retarded the HR20 cells in G1 phase and could not induce the cells to apoptosis. The cellular daunorubicin accumulation increased when HR20 cells were treated with low concentration of CsA and the reversal of drug resistance by CsA was unrelated to the retardation of cell cycle progression. High phosphorylation of about 50 kDa protein occured when HR20 cells were treated with CsA 10 micrograms.ml-1. The results domonstrate that cyclosporine A retarded the harringtonine-resistant HL-60 cells in G1 phase but induced HL-60 cells to apoptosis, and the retardation was unrelated to drug resistance.  相似文献   
9.
The Drosophila melanogaster genes, transient receptor potential (trp) and transient receptor potential-like (trpl) encode putative plasma membrane cation channels TRP and TRPL, respectively. We have stably co-expressed Drosophila TRPL with a Drosophila muscarinic acetylcholine receptor (DM1) in a Drosophila cell line (S2 cells). Basal Ca2+ levels measured using Fura-2/AM in unstimulated S2-DM1-TRPL cells were low and indistinguishable from untransfected cells, indicating that the TRPL channels were not constitutively active in this expression system. Activation of DM1 receptor in S2-DM1-TRPL cells by 100 microM carbamylcholine induced Ca2+ release from an intracellular Ca2+ pool followed by a Gd(3+)-insensitive Ca2+ influx. Pretreatment of S2-DM1-TRPL cells with 10 microM atropine abolished Gd(3+)-insensitive Ca2+ influx triggered by carbamylcholine, but the response was not blocked by prior incubation with pertussis toxin. TRPL channels could also be reliably activated by bath application of 1 microM thapsigargin for 10 min or 100 nM thapsigargin for 60 min in Ca(2+)-free solution. In some cells, TRPL channels activated by thapsigargin could further be activated by carbamylcholine. The findings suggest that, when stably expressed in the S2 cell line, TRPL may be regulated by two distinct mechanisms: (i) store depletion; and (ii) stimulation of DM1 receptor via pertussis-toxin insensitive G-protein (or the subsequent activation of PLC), but without further requirement for Ca2+ release.  相似文献   
10.
Light chain deposition disease is a severe complication of certain immunoproliferative disorders, due to the secretion of a monoclonal light chain which precipitates close to basement membranes of several tissues. A kappa isotype restriction and an unusual frequency of a variable region subgroup (VkappaIV) suggest that precise structural features govern the propensity of pathogenic light chains to precipitate in extracellular spaces. We studied primary structures of light chains from six patients with light chain deposition disease in comparison with light chains from other pathological conditions. Sequence alignment revealed the presence of certain amino acids only in light chain deposition disease, in particular non-polar replacing hydrophilic residues. To determine the role of these residues, structures of the variable domain from four kappa chains belonging to VkappaI and VkappaIV subgroups responsible for deposition disease were modeled using known immunoglobulins as templates. The most evident structural features shared by all pathogenic light chains were hydrophobic residues exposed to the solvent in complementarity determining regions 1 or 3. In contrast to immunoglobulin light chain- related amyloidosis, where deposition of organized material might be due to electrostatic interactions between light chain dimers, hydrophobic interactions could enhance amorphous precipitation in non- amyloid light chain deposition disease.   相似文献   
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