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M A Marano

Publications and source records attributed to M A Marano.

At least 19 recordsLinked to original sources

Current estimates from the National Health Interview Survey, 1996.

OBJECTIVES: This annual report presents national estimates, based on data from the National Health Interview Survey (NHIS), on the incidence of acute conditions, percent of medically attended acute conditions, number of disability days, episodes of persons injured and associated activity restriction, persons with activity limitation due to chronic conditions, restricted activity days associated with acute and chronic conditions, physician contacts and short-stay hospitalizations, as well as prevalence of chronic conditions and respondent assessed health status. This edition includes a section on trends in health statistics for 1982-96. SOURCE OF DATA: NHIS is a multistage probability sample survey conducted annually by interviewers of the Bureau of the Census for the National Center for Health Statistics. Data is collected during in-home interviews of the civilian noninstitutionalized U.S. population. Data collection procedures were similar from 1982 through 1996, but were changed after 1996. HIGHLIGHTS: In 1996 there were 163.5 acute conditions per 100 persons, (67.9% were medically attended) and 624.0 associated days of restricted activity per 100 persons. Of acute injuries, 91.4% were medically attended. The highest rates for chronic conditions per 1000 persons included arthritis (127.3), sinusitis (125.5), deformity and orthopedic impairment (111.6), and high blood pressure (107.1). Activity limitation due to chronic conditions was reported by 14.4% of persons. There were six physician contacts per person per year and 7.3% of the population had a hospitalization in the past year. During 1982-96, the prevalence of asthma increased and the rate and duration of hospitalizations decreased.

Acute Disease↗

Current estimates from the National Health Interview Survey, 1995.

OBJECTIVES: This report presents data on national estimates of the incidence of acute conditions, percent of medically attended acute conditions, number of disability days (including restricted activity and bed days, and work- or school-loss days), number of episodes of persons injured and associated activity restriction, prevalence of selected chronic conditions, number of activity limitations due to chronic conditions, number of restricted activity days associated with acute and chronic conditions, respondent-assessed health, number of physician contacts, and short-stay hospitalizations. METHODS: The National Health Interview Survey (NHIS) is a complex, multi-stage, probability sample survey conducted annually by trained interviewers of the U.S. Bureau of the Census for the National Center for Health Statistics. Information is collected during in-home interviews of the civilian noninstitutionalized U.S. population on a variety of health issues. RESULTS: The NHIS estimates that in 1995, there were 174.4 acute conditions per 100 persons. Of these, 67.3 percent were medically attended and this resulted in 674.6 days of restricted activity per 100 persons. Of acute injuries, 91.2 percent were medically attended. The most frequently reported rates for chronic conditions per 1,000 persons included sinusitis (141.3), arthritis (124.7), and deformity and orthopedic impairment (121.4). Some degree of activity limitation due to chronic conditions was reported by 14 percent of persons. There were about six physician contacts per person per year and 7.5 percent of the population had at least one hospitalization in the past year.

Absenteeism↗

Whole body and splanchnic leucine, phenylalanine, and glucose kinetics during endotoxemia in humans.

To examine the whole body and splanchnic tissue substrate handling during endotoxemia, an intravenous bolus of endotoxin was given to six healthy volunteers during primed, continuous infusions of [1-13C]leucine, [ring-2H5]phenylalanine, and [6,6-2H2]glucose. Whole body protein breakdown, based on whole body Leu and Phe appearance rates (Ra), increased in response to endotoxin given at time 0 (RaLeu 77 +/- 2 mol.kg-1 x h-1, t = 0 h; 88 +/- 6, t = 4 h; P < 0.05) (RaPhe 39 +/- 2 mol.kg-1 x h-1, t = 0; 46 +/- 3, t = 4 h; P < 0.05). Splanchnic amino acid balance (Bal) increased (BalLeu 7 +/- 4 mol.kg-1 x h-1, t = 0; 21 +/- 5, t = 2 h; P < 0.05) (BalPhe 3 +/- 2 mol.kg-1 x h-1, t = 0; 16 +/- 4, t = 2 h; P < 0.05) and can be accounted for by increased splanchnic uptake (Rd) of Phe and Leu (RdLeu 21 +/- 3 mol.kg-1 x h -1, t = 0; 37 +/- 7, t = 120 min; P < 0.05) (RdPhe 10 +/- 3 mol.kg-1 x h-1, t = 0; 24 +/- 5, t = 120 min; P < 0.05). Splanchnic conversion of Leu to ketoisocaproate increased with endotoxin administration (0.7 +/- 0.6 mol.kg-1 x h-1, t = 0; 8 +/- 3, t = 360 min; P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute-Phase Proteins↗

Glucocorticoid therapy alters hormonal and cytokine responses to endotoxin in man.

Previous experimental data have demonstrated that steroid pretreatment regulates endotoxin-elicited cytokine production. The timing of such hypercortisolemia also appears to be a major determinant of both the systemic and the cytokine response to infectious stimuli. Our study was undertaken to further study the in vivo influence of glucocorticoid infusion concurrent with and before endotoxin exposure in man. A total of 23 normal human subjects were given endotoxin (LPS) alone or pretreated with hydrocortisone infusion for 6 h immediately before and concomitant to LPS administration; or rendered hypercortisolemic for a 6-h period waiting 6, 12, or 144 h before LPS administration. LPS administration was followed by significant elevations in temperature (1.9 +/- 0.3 degrees C), pulse (29 +/- 6 bpm), and resting energy expenditure (26.2 +/- 0.4 kcal/kg/day) as well as epinephrine (236 +/- 59 pg/ml), cortisol (296 +/- 29), and C-reactive protein (4.2 +/- .03 mg/dl) as compared with base-line values. Levels of TNF and IL-6 that were not detectable before LPS administration, peaked, respectively, at 90 and 120 min after LPS (155 +/- 4 pg/ml, 12 +/- 1 U/ml). Glucocorticoids when given immediately before and concomitant with LPS significantly attenuated the temperature (0.8 +/- 0.01 degrees C) and pulse rate response (10 +/- 3 bpm) seen after LPS alone as well as suppressing peak levels of epinephrine (78 +/- 14 pg/ml) and C-reactive protein (undetected). TNF remained undetectable in this group although the IL-6 response (14 +/- 1 U/ml) was unchanged. With a 6-h interval between hydrocortisone infusion and LPS challenge, changes in temperature, pulse, resting energy expenditure, and hormone levels were similar to those seen after LPS alone whereas TNF remained undetectable and IL-6 levels were similar to subjects receiving LPS alone. Subjects receiving LPS after 12 or 144 h after hydrocortisone infusion displayed hemodynamic and hormonal responses similar to the LPS alone group, yet mounted significantly greater circulating levels of both IL-6 (117 +/- 14 U/ml, 160 +/- 51 U/ml at 12 and 144 h) and TNF (609 +/- 173, 671 +/- 132 pg/ml at 12 and 144 h) to those observed after LPS alone. We conclude that antecedent periods of hypercortisolemia participate in regulation of the hemodynamic, hormonal, and cytokine responses to endotoxin and that a complex temporal relationship between hypercortisolemia and LPS induced cytokine and systemic responses exists.

Adult↗

Comparison of peripheral blood leukocyte kinetics after live Escherichia coli, endotoxin, or interleukin-1 alpha administration. Studies using a novel interleukin-1 receptor antagonist.

OBJECTIVE: This study was undertaken to evaluate whether hematologic and immunologic effects observed after bacteremia and endotoxemia in the host could be replicated by administration of recombinant human interleukin-1 alpha (IL-1 alpha) in a primate model. Furthermore, to determine whether endogenously produced interleukin-1 (IL-1) contributes to the changes observed during endotoxemia or gram-negative septic shock, a specific IL-1 receptor antagonist (IL-1 ra) was administered. SUMMARY BACKGROUND DATA: The lipopolysaccharide (LPS) component of the outer membrane of gram-negative bacteria initiates a constellation of metabolic and immunologic host responses. IL-1, a macrophage-derived cytokine, acts as a key mediator in the host response to infection and inflammation. METHODS: Baboons were randomly assigned to receive either recombinant human IL-1 alpha, LPS, or live Escherichia coli both with or without concomitant administration of IL-1ra. Blood was collected hourly and analyzed using flow cytometric techniques. RESULTS: Both endotoxemia and live E. coli bacteremia induced an acute granulocytopenia; however, the granulocytopenia gradually resolved in the endotoxemic group, but was sustained in the bacteremic group. An early lymphopenia and monocytopenia was elicited by LPS or E. coli and persisted throughout the experiment. Recombinant human IL-1 alpha induced the following: (1) an early, transient decline in granulocytes followed by a sustained granulocytosis; (2) a lymphopenia; and (3) a transient monocytopenia followed by a gradual return to baseline. Although IL-1ra had no effect on leukocyte kinetics with either live E. coli or LPS, the IL-1ra significantly abrogated the monocytopenia seen with recombinant human IL-1 alpha administration alone. CONCLUSIONS: These results suggest that administration of recombinant human IL-1 alpha can replicate some of the characteristic patterns of hematologic change associated with bacteremia and endotoxemia. However, an endogenous IL-1 response is not required for these changes to occur. Rather, the data suggest that other inflammatory mediators induced by endotoxemia or gram-negative bacteremia, such as tumor necrosis factor-alpha (TNF alpha), may be involved.

Animals↗

Splanchnic bed utilization of leucine and phenylalanine in humans.

To study the fate of enterally delivered essential amino acids, leucine and phenylalanine, 14 healthy adults were infused in the postabsorptive state with [1-13C]leucine, [5,5,5-2H3]leucine, and [phenyl-2H5]phenylalanine for 7 h in a crossover design by intravenous and nasogastric tube routes. The amount of enterally delivered tracer that was sequestered by the splanchnic bed on the first pass was 21 +/- 1, 17 +/- 3, and 29 +/- 2 for the [13C]leucine, [2H]leucine, and [2H]phenylalanine tracers, respectively. Less than 2% of the nasogastric [1-13C]leucine tracer was oxidized on the first pass. We estimate that 40% of the nasogastric leucine tracer that was sequestered on the first pass was converted to alpha-ketoisocaproate and released, and 50% was incorporated into newly synthesized proteins. Assuming that less phenylalanine is incorporated into protein than leucine because of the lower abundance of phenylalanine in protein compared with leucine, we estimate that 80% of the extracted nasogastric phenylalanine tracer was converted to tyrosine. The study design also indicated a significant effect of duration of tracer infusion on the results, presumably due to recycling of tracer from rapidly turning over protein.

Adult↗

Splanchnic bed utilization of glutamine and glutamic acid in humans.

To study the fate of enterally delivered nonessential amino acids, glutamine and glutamate, 14 healthy adults were infused in the postabsorptive state with [2-15N]glutamine and [15N]glutamate for 7 h by intravenous (iv) and nasogastric (ng) tube routes. The amount of enterally delivered tracer that was sequestered by the splanchnic bed on the first pass was 54 +/- 4 and 88 +/- 2% for the [2-15N]glutamine and [15N]glutamate tracers, respectively. Only 46 and 12% of the ng glutamine and glutamate tracers entered systemic blood, respectively. The relative amount of 15N transferred from glutamate to glutamine, the transaminating amino acids leucine, isoleucine, valine, and alanine, and to proline was significantly higher when the [15N]glutamate was infused by the ng vs. iv route. The same was also true for [2-15N]glutamine, which presumably transferred 15N after it was converted to glutamate. Thus we conclude that the splanchnic bed sequesters over one-half of the glutamine and almost all of the glutamate delivered to it in the postabsorptive state. There is production of transaminating amino acids in the splanchnic bed, and the splanchnic bed produces simultaneously both glutamine from glutamate and glutamate from glutamine.

Adult↗

Interleukin-1 receptor antagonist circulates in experimental inflammation and in human disease.

Interleukin-1 receptor antagonist (IL-1ra) is a 22-Kd protein that shares homology with IL-1 beta, binds to the IL-1 receptor, but has no known agonist properties. This inhibitor appears to be the first cytokine whose sole function is to block the actions of another cytokine. Exogenous IL-1ra administration has been shown to reduce mortality in experimental septic shock. We now report that IL-1ra is endogenously produced and circulates in experimental inflammation and in clinical disease. After experimental endotoxemia in human volunteers, IL-1ra concentrations increase from a baseline concentration of 460 +/- 200 pg mL-1 to 14,870 +/- 290 pg mL-1 at 3 hours (P less than .05). IL-1ra is also detectable in all plasma samples from critically ill patients with a mean concentration of 8,680 +/- 2,060 pg mL-1 (range 320 to 55,370 pgs mL-1). In nonhuman primates, Escherichia coli septic shock induces elevated plasma levels of IL-4ra (P less than .05). However, in animals that eventually succumb to septic shock, Il-1ra appears in quantities presumed inadequate to block the pathologic sequelae associated with high IL-1 beta levels. The findings suggest that IL-1ra may play a role in modulating the systemic host responses to a variety of nonlethal disease states by altering the balance between cytokines and their antagonists.

Adult↗

Pediatric burns. An overview.

This article describes the management of burn injuries in children. It begins with an epidemiologic description of pediatric burns. Attention is given to emergency care, burn wound evaluation, operative management, and rehabilitative goals.

Burns↗

Tolerance to endotoxin prevents mortality in infected thermal injury: association with attenuated cytokine responses.

Endotoxin, a lipopolysaccharide (LPS), is a bacterial cell wall product instrumental in producing deleterious host responses to infection. This LPS appears to act, in part, by triggering release of endogenous mediators such as cytokines. Repeated exposures to endotoxin produce attenuated responses to this molecule. To examine the mechanisms and biologic consequences of this tolerance to LPS, Wistar rats were subjected to a 14-day course of LPS administration. Tolerance to LPS with regard to anorexia, weight loss, and acute-phase responses was noted. Attenuation of these physiologic responses was accompanied by abrogation of circulating cytokine appearance in response to endotoxin, suggesting that tolerance to LPS is in part due to a decreased production of cytokines. Tolerance to LPS also diminished the response to a subsequent infected thermal injury, as measured by food intake, body weight, fibrinogen levels, and mortality. Thus, clinical conditions involving repeated exposure to LPS may modify the host's responses to subsequent injury. The attenuated responses to injury accompanying the decreased production of cytokines further implicate cytokines in the pathogenesis of injury and disease.

Acute-Phase Reaction↗

Interleukin-1 receptor blockade improves survival and hemodynamic performance in Escherichia coli septic shock, but fails to alter host responses to sublethal endotoxemia.

The present study was undertaken to evaluate the extent to which an endogenous interleukin-1 (IL-1) response contributes to the hemodynamic and metabolic consequences of sublethal endotoxemia or lethal Gram-negative septic shock. Young, healthy baboons received either a sublethal dose of lipopolysaccharide (LPS) or an LD100 of live Escherichia coli bacteria, and one half of the animals in each group were continuously infused with IL-1 receptor antagonist (IL-1ra). Plasma IL-1 beta was not detected in this model of endotoxemia. Administration of IL-1ra had only minimal effects on the modest hemodynamic and metabolic responses to sublethal endotoxemia, and did not attenuate the plasma cytokine response. In contrast, high circulating levels of IL-1 beta (range 300-800 pg/ml) were seen during lethal E. coli septic shock. IL-1ra treatment significantly attenuated the decrease in mean arterial blood pressure (MAP) (from -72 +/- 8 to -43 +/- 6 mm Hg; P less than 0.05) and cardiac output (from -0.81 +/- 0.17 to -0.48 +/- 0.15 liter/min; P less than 0.05), and significantly improved survival from 43 to 100% at 24 h (P less than 0.05). The plasma IL-1 beta and IL-6 responses to lethal E. coli septic shock were also significantly diminished by IL-1ra treatment (P less than 0.05), whereas tumor necrosis factor-alpha (TNF alpha) concentrations were unaffected. We conclude that an exaggerated systemic IL-1 beta response is characteristic of lethal E. coli septic shock, and contributes significantly to the hemodynamic and metabolic consequences of E. coli septic shock. IL-1ra can significantly attenuate the cytokine cascade and improve survival.

Animals↗

Resuscitation of the thermally injured patient.

This article briefly reviews the pathophysiology of burn wounds as a basis for a more detailed discussion on the resuscitation of burn patients with lactated Ringer's solution or other regimens. The complications resulting from such resuscitation are also reviewed.

Burns↗

IL-8 in septic shock, endotoxemia, and after IL-1 administration.

Much effort has been directed toward elucidating the host response to sepsis and inflammation, resulting in the definition of a cascade of endogenous mediators that direct metabolic and immunological responses. Here we report that IL-8, a novel cytokine produced by a variety of cells in vitro in response to stimulation with bacterial LPS and the proinflammatory cytokines, appears in the circulation of primates in vivo during septic shock, sublethal endotoxemia, and after the administration of IL-1 alpha. The magnitude of the IL-8 response correlates with the severity of the insult, and levels of IL-8 peak relatively late, after those of TNF-alpha and IL-1 beta, and simultaneously with those of IL-6. IL-8 has been primarily defined as a selective activator and chemoattractant of neutrophils, and we demonstrate that after LPS or IL-1 alpha infusion, circulating neutrophil numbers rapidly recover from an initial neutropenia while IL-8 concentrations are maximal, supporting the hypothesis that IL-8 influences circulating leukocyte populations in vivo. We conclude that IL-8 is another participant in the cytokine cascade elicited by sepsis and inflammation and, as such, may play a significant role in host defense and disease.

Animals↗

Comparison between effects of interleukin-1 alpha administration and sublethal endotoxemia in primates.

Interleukin (IL)-1 is an early mediator of host response to inflammation, although its contribution to individual components of the acute phase reaction is still unclear. To evaluate how the hemodynamic, metabolic, and hormonal responses to sublethal endotoxemia compare with IL-1 administration, baboons received intravenously either lipopolysaccharide (LPS) or 0.1, 10, or 100 micrograms/kg IL-1 alpha. LPS induced an early tachycardia and a fall in mean arterial pressure, as well as lacticacidemia and hypoaminoacidemia. Similar hemodynamic and metabolic changes were seen with 10 or 100 micrograms/kg of IL-1 alpha. An increase in adrenocorticotropic hormone and fall in serum iron were induced by IL-1 alpha but not by LPS. Plasma tumor necrosis factor-alpha (TNF-alpha) was not measurable after IL-1 alpha administration, whereas LPS induced a monophasic TNF-alpha response. IL-6 levels were significantly greater after LPS than IL-1 alpha administration. Histopathological lesions, similar in LPS- and 100 micrograms/kg IL-1 alpha-treated groups, were present only in the adrenal cortex. We conclude that many, but not all, of the effects of sublethal endotoxemia can be replicated by IL-1 alpha administration, and these responses are dose dependent.

Amino Acids↗

Skeletal muscle amino acid and myofibrillar protein mRNA response to thermal injury and infection.

Skeletal muscle changes associated with severe injury were investigated in male Wistar rats subjected to 30% full thickness scald injury (burn) and thermal injury followed by immediate colonization with 10(8) colony-forming units of Pseudomonas aeruginosa (BI). Freely fed animals (FF) and animals pair fed to the BI animals (PF) served as controls. Thermal injury in conjunction with infection produced a rapid and sustained muscle cellular membrane depolarization (transmembrane potential difference at 12 h after injury: FF 92.1 +/- 0.3 and BI 85.2 +/- 2.3 mV; P less than 0.05). This was followed by body weight loss and skeletal muscle protein wasting (gastrocnemius protein at 7 days: FF 0.35 +/- 0.01 and BI 0.16 +/- 0.03 g; P less than 0.05) and intracellular high-energy phosphate depletion (ATP at 10 days: FF 6.6 +/- 0.4 and BI 4.5 +/- 0.4 mumol/g tissue; P less than 0.05). These body and cellular changes were not accounted for by the anorexia alone. Marked alterations in intracellular free amino acids were also noted in the BI group characterized by increases in levels of all amino acids (total intracellular free amino acids at 7 days: FF 51 +/- 7 and BI 91 +/- 12 mM; P less than 0.05) except intracellular glutamine (at 7 days: FF 6.0 +/- 0.2 and BI 2.4 +/- 0.6 mM; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗