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PubMed2000

Risk factors for abattoir condemnation of turkey carcasses due to cyanosis in southern Ontario.

Cyanosis is a category of condemnation for poultry, as defined by Agriculture and Agrifood Canada. A retrospective study to examine the seasonal patterns and trends for turkey cyanosis condemnation was conducted for the years 1987 to 1995 with the use of condemnation records made available by a single abattoir in Ontario. Condemnation for cyanosis had a significant seasonal pattern, with major losses occurring in the colder months (October to March). A prospective longitudinal study was conducted during January to March and October to December 1996 in the same abattoir and the 75 turkey farms that contracted to process their birds through it and all the 913 truckloads of turkeys processed in these two 3-mo periods. The data from this prospective study were used for multivariate modeling of the effects of potential risk factors on the incidence of cyanosis. Risk factors (at P < or = 0.05) included bird type (broiler age turkeys, mature toms, and mature hens compared to toms and hens), ambient temperature (cold: -9.9 to 0.0 C and very cold: < or =-10.0 C compared to mild: >0.0 C), clean-out lot (the last shipped from a poultry house), shipping time > or =8 h, and emaciation (proportion of turkeys in the lot condemned for insufficient muscle mass). The crate density was a sparing factor, and an increase in turkey density during shipping resulted in a lower incidence of cyanosis. This study suggested that the number of turkeys condemned for cyanosis was associated with cold, shipping stress, and subclinical syndromes.

Abattoirs↗

PubMed2001

Furosemide does not facilitate pulmonary vasodilation in broilers during chronic or acute unilateral pulmonary arterial occlusion.

Furosemide (FURO) is a diuretic and a putative pulmonary vasodilator that, when added to broiler diets, previously has been shown to reduce the cumulative pulmonary hypertension syndrome (PHS) mortality induced by cold temperatures. The objective of the present study was to evaluate the influence of dietary FURO on the pulmonary vasculature in broilers undergoing chronic or acute unilateral pulmonary arterial occlusion. Broilers were fed a standard ration throughout the entire experiment (Control group) or the same ration supplemented with 0.015% (wt/wt) FURO from Day 14 to 42 (FURO group). In the present study chicks were chosen at random at 16 to 18 d of age to undergo sham surgery or a chronic unilateral pulmonary artery clamp (PAC) procedure. Diet and surgical treatments resulted in Control-Sham, FURO-Sham, Control-PAC, and FURO-PAC groups. The Control-PAC and FURO-PAC groups did not differ in body weight or right:total ventricular weight ratios (RV:TV). The postsurgical mortality, ascites mortality, and mortality due to other causes did not differ between the Control-PAC and FURO-PAC groups. Plasma Na+ (P < or = 0.05) was lower in the FURO-Sham group than in the Control-Sham group. Broilers from the same hatch were fed Control or FURO diets and surgically prepared for acute unilateral pulmonary arterial occlusion by using a snare. Tightening of the snare triggered characteristic increases in pulmonary blood flow, pulmonary arterial pressure, and pulmonary vascular resistance. Across all of these variables, the Control and FURO groups did not differ during any sample interval. Dietary FURO did not affect body weight, hematocrit, or RV:TV. Dietary FURO at 0.015% (wt/wt) does not appear to influence the pulmonary vasculature in broilers, but it may prolong the survival of broilers during the pathophysiological progression of PHS.

Animals↗

PubMed2004

Investigation of proton conductance in liver mitochondria of broilers with pulmonary hypertension syndrome.

We previously reported an impaired ability to regulate hepatic mitochondrial state 4 respiration rate in response to sequential additions of adenosine diphosphate in pulmonary hypertension syndrome (PHS). As proton conductance is a major contributor to State 4 respiration, the major goal of this study was to investigate the nature of proton conductance in hepatic mitochondria isolated from broilers with and without PHS. Broilers were placed on floor litter in environmental chambers and exposed to cold temperatures (15 degrees C) from 3 to 7 wk of age to induce PHS. Liver mitochondria were isolated from birds that exhibited PHS (cyanosis, right ventricular weight ratio > 0.30) or from birds that appeared healthy (no cyanosis, right ventricular weight ratio < 0.27). Isolated mitochondria were placed in a chamber equipped with the ability to measure oxygen content and mitochondrial membrane potential. The mitochondrial membrane potential was assessed by an ion sensitive electrode to measure the distribution of methyltriphenylphosphonium across the inner mitochondrial membrane. Proton conductance was assessed by simultaneously measuring State 4 oxygen consumption rate as respiration was progressively inhibited with increasing concentrations of malonate. The addition of cardiolipin, a lipid found in high concentrations in mitochondrial membranes that can alter proton conductance, had no affect on respiration or mitochondrial membrane potential in either group. The relationship of curves depicting State 4 respiration and mitochondrial membrane potential indicates that PHS mitochondria exhibit impaired substrate oxidation and reduced proton conductance relative to controls. These findings provide further characterization of the altered cellular oxygen utilization in broilers with PHS.

Animals↗

PubMed1994

Effects of high-frequency transcutaneous electrical nerve stimulation on limb blood flow in healthy humans.

BACKGROUND AND PURPOSE: Although transcutaneous electrical nerve stimulation (TENS) has been used clinically for more than 20 years, the hemodynamic effects of this intervention remain controversial. Our goal was to determine the effects of high-frequency TENS on calf blood flow in healthy subjects. SUBJECTS: Four men and seven women ranging in age from 20 to 44 years (mean = 30, SD = 9) served as subjects. METHODS: We measured calf blood flow during 20-minute TENS applications over the common peroneal and tibial nerves at intensities above and below the motor threshold. RESULTS: Calf blood flow was not changed by sensory-level TENS (3.2 +/- 1.0 versus 2.9 +/- 1.0 mL/100 mL/min) or by motor-level TENS (3.1 +/- 1.2 versus 2.8 +/- 1.0 mL/100 mL/min). CONCLUSION AND DISCUSSION: Neither sensory-level nor low-intensity motor-level TENS applied over peripheral nerves at clinically relevant pulse durations and frequencies altered limb blood flow in asymptomatic individuals. The applicability of these findings in conditions of abnormally elevated or diminished vascular resistance has not been determined.

Adult↗

PubMed2000

Risk factors associated with neonatal hypothermia during cleaning of newborn infants in labour rooms.

Cleaning newborn infants with coconut oil shortly after birth is a common practice in Malaysian labour rooms. This study aimed: (1) to determine whether this practice was associated with a significant decrease in the core temperature of infants; and (2) to identify significant risk factors associated with neonatal hypothermia. The core temperature of 227 randomly selected normal-term infants immediately before and after cleaning in labour rooms was measured with an infrared tympanic thermometer inserted into their left ears. Their mean post-cleaning body temperature (36.6 degrees C, SD = 1.0) was significantly lower than their mean pre-cleaning temperature (37.1 degrees C, SD = 1.0; p < 0.001). Logistic regression analysis showed that the risk factors significantly associated with pre-cleaning hypothermia (< 36.5 degrees C) were: (1) not being placed under radiant warmer before cleaning p = 0.03); and (2) lower labour room temperature (p < 0.001). Logistic regression analysis also showed that the risk factors significantly associated with post-cleaning hypothermia were: (1) lower labour room temperature (p < 0.001); (2) lower pre-cleaning body temperature (p < 0.001); and (3) longer duration of cleaning (p = 0.002). In conclusion, to prevent neonatal hypothermia, labour room temperature should be set at a higher level and cleaning infants in the labour room should be discouraged.

Body Temperature↗

PubMed2001

Neither nalbuphine nor atropine possess special antishivering activity.

The special antishivering action of meperidine may be mediated by its kappa or anticholinergic actions. We therefore tested the hypotheses that nalbuphine or atropine decreases the shivering threshold more than the vasoconstriction threshold. Eight volunteers were each evaluated on four separate study days: 1) control (no drug), 2) small-dose nalbuphine (0.2 microg/mL), 3) large-dose nalbuphine (0.4 microg/mL), and 4) atropine (1-mg bolus and 0.5 mg/h). Body temperature was increased until the patient sweated and then decreased until the patient shivered. Nalbuphine produced concentration-dependent decreases (mean +/- SD) in the sweating (-2.5 +/- 1.7 degrees C. microg(-1). mL; r(2) = 0.75 +/- 0.25), vasoconstriction (-2.6 +/- 1.7 degrees C. microg(-1). mL; r(2) = 0.75 +/- 0.25), and shivering (-2.8 +/- 1.7 degrees C. microg(-1). mL; r(2) = 0.79 +/- 0.23) thresholds. Atropine significantly increased the thresholds for sweating (1.0 degrees C +/- 0.4 degrees C), vasoconstriction (0.9 degrees C +/- 0.3 degrees C), and shivering (0.7 degrees C +/- 0.3 degrees C). Nalbuphine reduced the vasoconstriction and shivering thresholds comparably. This differs markedly from meperidine, which impairs shivering twice as much as vasoconstriction. Atropine increased all thresholds and would thus be expected to facilitate shivering. Our results thus fail to support the theory that activation of kappa-opioid or central anticholinergic receptors contribute to meperidine's special antishivering action.

Adult↗

PubMed2006

Impact of hypothermia on the response to neuromuscular blocking drugs.

Muscle strength is reduced during hypothermia, both in the presence and in the absence of neuromuscular blocking drugs. A 2 degrees C reduction in body temperature may double the duration of neuromuscular blockade. Central body and muscle temperatures decline in parallel, as long as peripheral vasoconstriction does not occur. A reduction in muscle strength must be expected at a body temperature less than 36 degrees C (corresponding to a muscle temperature of approximately 35 degrees C). Local cooling of the hand may make adductor pollicis twitch tension monitoring less useful during clinical anesthesia. The efficacy of neostigmine is maintained during mild hypothermia. The use of a nerve stimulator is strongly recommended to monitor the effect of neuromuscular blocking drugs during intraoperative hypothermia.

Animals↗

PubMed1994

The effect of frostbite on the reconstructed ear.

A 17-year-old patient whose left ear was reconstructed using a lateral arm fascia and skin graft had done well until one episode of cold exposure approximately two years after the reconstruction. This thermal injury resulted in a localized area of composite tissue loss demonstrating that the reconstructed ear had a higher susceptibility to cold temperatures. The transferred fascia did, however, allow a stable base for granulation and reepithelialization, showing the continued vascularity and regenerative capacity of the transferred tissue. A discussion is provided regarding the susceptibility of free transferred fascia and its regenerative capacity.

Adolescent↗

PubMed2006

Glomus tumor of the index finger.

A 41-year-old female patient presented with localized worsening subungual pain of her right index finger. Subsequent diagnostic evaluation revealed the presence of a glomus tumor. A glomus tumor is a rare tumor with a predilection for the hand. Classic symptoms include pain, pain with pressure, and pain with cold temperature. We present a completely updated literature review that addresses the epidemiology, pathology, presentation, diagnostic evaluation, classification, histology, genetics, and treatment options for glomus tumors.

Adult↗

PubMed2002

Cryoglobulinemia vasculitis.

Cryoglobulins are immunogloblulins that persist in the serum, precipitate with cold temperature, and resolubilize when rewarmed. Mixed cryoglobulins, composed of different immunoglobulins, with a monoclonal component in type II and only polyclonal immunoglobulins in type III, are associated with connective tissue, malignant hematologic, or obvious infectious diseases. The syndrome of mixed cryoglobulinemia represents the consequence of an immune complex-type vasculitis. It is characterized by the clinical triad of purpura, arthralgia, and asthenia, and may involve numerous organs, particularly the peripheral nervous system and the kidneys. Mixed cryoglobulinemia frequently is associated with clinical and biologic evidence of liver disease. It seems fairly clear that mixed cryoglobulinemia is often a manifestation of underlying chronic active or persistent hepatitis. In the last 10 years, many studies have demonstrated that infection with hepatitis C virus is involved in the pathogenesis of most mixed cryoglobulinemia vasculitis. This review analyzes the main published data of hepatitis C virus-mixed cryoglobulinemia, the role of liver alterations, the predictive factors associated with mixed cryoglobulin production in hepatitis C virus patients and whether its character is symptomatic, and the different types of vasculitis associated with hepatitis C virus chronic infection and their treatments.

Antiviral Agents↗

PubMed1992

Pluronic F 127 liquid sensitizes mice to low doses of Escherichia coli lipopolysaccharide.

BACKGROUND AND METHODS: In murine models of endotoxemia, large amounts of lipopolysaccharide have to be administered to induce mortality. If mice are pretreated with D-galactosamine, the amount of lipopolysaccharide required to induce mortality is significantly lowered. Pluronic F 127 liquid is a relatively non-toxic copolymer that exhibits reverse gelation properties. Thus, it is a liquid at cold temperature and a gel at body temperature. The present studies were performed to ascertain whether the reverse gelation properties of Pluronic F 127 liquid could be used in devising a model of septic shock where a sustained delivery of lipopolysaccharide occurred. In evaluating this model, dose-response studies were conducted with lipopolysaccharide when a) it was administered intraperitoneally in saline or in Pluronic F 127 liquid, and b) it was administered intravenously to mice that had been pretreated with saline or Pluronic F 127 liquid. Mortality was followed for up to 72 hrs. RESULTS: Various doses of Escherichia coli lipopolysaccharide dissolved in saline or in Pluronic F 127 liquid were administered intraperitoneally to mice. The lethal dose of lipopolysaccharide required to kill 50% of the mice (LD50) administered in Pluronic F 127 liquid was approximately ten- to 15-fold less than the values obtained for lipopolysaccharide administered in saline. This decrease in the LD50 of lipopolysaccharide was also observed if the mice were treated intraperitoneally with Pluronic F 127 liquid and challenged 6 hrs later with iv lipopolysaccharide. The concentrations of tumor necrosis factor and interleukin-6 in the plasma were significantly higher when a low dose of lipopolysaccharide was administered to mice that had been pretreated with Pluronic F 127 liquid. While there was no effect on the liver enzymes, Pluronic F 127 liquid caused an increase in the plasma triglycerides. CONCLUSIONS: The data reported in this paper indicate that the LD50 of lipopolysaccharide is significantly decreased if it is administered in Pluronic F 127 liquid or administered to mice that have been pretreated with the Pluronic F 127 liquid. Thus, Pluronic F 127 liquid appears to sensitize mice to low levels of lipopolysaccharide. Unlike the D-galactosamine model, lipopolysaccharide can be administered as late as 6 hrs after treatment with Pluronic F 127 liquid. While the mechanisms by which Pluronic F 127 liquid sensitizes mice is not known, plasma triglycerides were increased in mice treated with this agent, suggesting that tissues responsible for the synthesis and/or degradation of triglycerides play a role in this sensitization process.

Animals↗

PubMed1992

A means of retaining chromosome damage in irradiated human lymphocytes.

The method of premature chromosome condensation has been used to determine the damage induced by ionizing radiation to chromosomes in G1 human lymphocytes. The method has also demonstrated the repair of such damage with time following exposure. This study shows how storage at a cold temperature can be used to retain this damage for further biodosimetric study.

Animals↗

PubMedDate not supplied

Core temperature response to immersed bicycle ergometer exercise at water temperatures of 21 degrees, 25 degrees, and 29 degrees C.

A bicycle ergometer modified for aquatic exercise was used to determine the effects of immersion on core temperature during submaximal exercise at different water temperatures. An exercise intensity (60% of maximal oxygen consumption) and duration (30 minutes) considered appropriate for cardiovascular conditioning were used. These data will be useful in cardiovascular and leg-strengthening hydrotherapy programs. Rectal temperature, skin temperature, and a rating of thermal comfort were studied in five normal men (14.8% +/- 5.6% fat) during headout immersion at water temperatures of 21.1 degrees, 25.3 degrees, and 29.4 degrees C and exercise in air of 21.1 degrees C. Subjects were immersed for 30 minutes during static and exercise (63% +/- 0.6% maximal oxygen consumption) conditions. Data were collected every 5 minutes and analyzed by repeated measured analysis of variance. At water temperatures, rectal temperature fell from control during static immersion (p less than or equal to 0.05) and was lower than control at the end of the 30-minute recovery period (p less than or equal to 0.05). During exercise there was no change in rectal temperature at water temperatures of 21.1 degrees and 25.3 degrees C; however, rectal temperature rose at water temperatures of 29.4 degrees (p less than or equal to 0.05) and air 21.1 degrees C (p less than or equal to 0.05). At the end of recovery rectal temperature was lower than control at water temperatures 21.1 degrees C (p less than or equal to 0.05) and greater than control at water temperatures 29.4 degrees C (p less than or equal to 0.05). There was no change from control in rectal temperatures at water temperatures 25.3 degrees C and air at 21.1 degrees C. These results indicate that immersion in 25.3 degrees and 21.1 degrees C water effectively attenuates the rise in rectal temperature during exercise at 63% of maximal oxygen consumption, whereas immersion in 29.4 degrees C water does not. In addition, both skin and rectal temperatures affect perception of thermal state but do not give the subjects an accurate estimation of thermal balance.

Adult↗

PubMed2000

Pulpal responses to cooling tooth temperatures.

This investigation measured pulpal blood flow and sensitivity to electrical stimulation as tooth temperatures were lowered. Dark rubber dams were placed on test teeth before placement of the cooling device in an attempt to shield gingival microcirculation. Laser Doppler flowmetry was used to measure pulp blood flow, whereas sensory thresholds were recorded simultaneously using an electric pulp tester. As tooth temperatures were lowered, the teeth became less responsive. Pulp blood flow also slowed, but did not completely stop. Results indicated that sensory thresholds were altered, and in some subjects, abolished, without total cessation of pulpal blood flow.

Adult↗

PubMed1994

Plasma erythrocyte relationship of catecholamines in human blood.

The equilibrating process of catecholamines (CAs) between plasma and red blood cells (RBC) was studied by measuring their erythrocyte/plasma concentration gradient (E/P ratio); ratio of E/P > 1 for a given amine was considered the consequence of its accumulation in or on RBC. We studied in vitro human blood obtained from 9 polycythemic patients from whom blood was drawn in control condition and in response to loading with exogenous CAs. Preliminary study showed a lack of difference in results obtained in these patients from those in 9 healthy volunteers and confirmed that RBC accumulate dopamine (DA) and epinephrine (EPI) but not norepinephrine (NE). When a moderate amount of exogenous CAs was added, plasma and RBC concentrations were increased, with a delay between the two compartments indicated by a decrease in the E/P ratio of DA and EPI. When a large amount of exogenous CAs was added, their RBC concentrations were in direct proportion to their plasma concentrations. Thus, the kinetics of CA equilibration between plasma and RBC appears to be dependent on their chemical structure (DA is more easily accumulated than NE) and their plasma concentrations. Physiologically, the E/P ratio of DA was significantly greater than 1, suggesting that RBC maintained their capacity to accumulate DA even when DA plasma concentration was very high. Additional studies demonstrated that accumulation of CAs in or on RBC is a reversible process, inhibited by cold temperature and increased when blood pO2 is drastically reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Catecholamines↗

PubMed2004

Phalangeal microgeodic syndrome resulting in rapid digital shortening.

Microgeodic phalangeal syndrome is a rare condition affecting the fingers in children. Radiographically, the affected phalanges show sclerosis with multiple small areas of osteolysis. The pathogenesis of microgeodic phalangeal syndrome is considered to be a transient disturbance of the peripheral circulation caused by cold temperatures. In most cases, the symptoms and the radiographic changes return to normal within several months without any treatment. We present a rare case of microgeodic phalangeal syndrome in the middle phalanx of the right index finger in an 8-year-old girl, in whom the affected phalanx shortened within 6 weeks of the initial presentation. It was speculated that minor trauma to the finger might have contributed to the collapse and shortening of the phalanx. The current case indicates that the use of a splint for the affected finger in the early period after onset of symptoms might be recommended to avoid digital shortening.

Bone Diseases↗

PubMed2005

Cutaneous vasculitis update: diagnostic criteria, classification, epidemiology, etiology, pathogenesis, evaluation and prognosis.

Vasculitis, inflammation of the vessel wall, can result in mural destruction with hemorrhage, aneurysm formation, and infarction, or intimal-medial hyperplasia and subsequent stenosis leading to tissue ischemia. The skin, in part due to its large vascular bed, exposure to cold temperatures, and frequent presence of stasis, is involved in many distinct as well as un-named vasculitic syndromes that vary from localized and self-limited to generalized and life-threatening with multi-organ disease. To exclude mimics of vasculitis, diagnosis of cutaneous vasculitis requires biopsy confirmation where its acute signs (fibrinoid necrosis), chronic signs (endarteritis obliterans), or past signs (acellular scar of healed arteritis) must be recognized and presence of extravascular findings such as patterned fibrosis or collagenolytic granulomas noted. Although vasculitis can be classified by etiology, many cases have no identifiable cause, and a single etiologic agent can elicit several distinct clinicopathologic expressions of vasculitis. Therefore, the classification of cutaneous vasculitis is best approached morphologically by determining vessel size and principal inflammatory response. These histologic patterns roughly correlate with pathogenic mechanisms that, when coupled with direct immunofluorescent examination, anti-neutrophil cytoplasmic antibody (ANCA) status, and findings from work-up for systemic disease, allow for specific diagnosis, and ultimately, more effective therapy. Herein, we review cutaneous vasculitis focusing on diagnostic criteria, classification, epidemiology, etiology, pathogenesis, and evaluation of the cutaneous vasculitis patient.

Humans↗

PubMed2003

Transient renal dysfunction with Raynaud's phenomenon: is there a connection?

We describe a patient with an episode of severe Raynaud's phenomenon and early or mild scleroderma who presented with a transient elevation of her serum creatinine that resolved spontaneously after 2 days. Vascular response to cold temperatures has been described in vascular beds other than the extremities, and a similar phenomenon in the kidney might have been responsible for the transient renal dysfunction. Possible mechanisms to explain this phenomenon are discussed. Vasospasm merits consideration as an uncommon but largely reversible cause of elevated creatinine in patients with Raynaud's phenomenon.

Journal Article↗