Biomedical subjects

T Juvonen

Publications and source records attributed to T Juvonen.

96 records · Page 6Linked to original sources

PubMed1991

Immunohistochemical demonstration of acetaldehyde-modified epitopes in human liver after alcohol consumption.

Acetaldehyde, the toxic product of ethanol metabolism in the liver, covalently binds to a variety of proteins. Recent studies indicate that such binding can stimulate the production of antibodies against the acetaldehyde adducts. We raised rabbit antibodies which recognized various protein-acetaldehyde conjugates but not the corresponding control proteins. Such antibodies were used in immunohistochemical studies to find out whether acetaldehyde-generated epitopes can be detected from liver specimens of 13 human subjects with different degrees of alcohol consumption. While the specimens obtained from alcohol abusers (n = 4) and alcoholics (n = 3) exhibited marked positive staining for acetaldehyde adducts inside the hepatocytes in a granular uneven pattern, the control samples (n = 6) were almost devoid of immunoreactivity. In the alcohol abusers with an early stage of alcohol-induced liver damage, staining was detected exclusively around the central veins. The data indicate that intracellular acetaldehyde adducts occur in the centrilobular region of the liver of individuals consuming excessive amounts of alcohol. Immunohistochemical detection of such adducts may prove to be of value in the early identification of alcohol abuse and in elucidating the mechanisms of alcohol-induced organ damage.

Acetaldehyde↗

PubMed1985

Impact of new imaging techniques on survival in cancer of the head of the pancreas and the periampullary region.

The impact of new imaging techniques on diagnostic delay and on survival in carcinoma of the head of the pancreas and the periampullary region was investigated. The study comprised 67 patients treated before (1968-1975) and 82 treated after (1979-1981) the introduction of new imaging techniques at Oulu University Central Hospital. The symptomatology, diagnostic delay and survival rates were identical in both groups, but the number of patients per year increased significantly during the latter period. The study indicated that the new imaging techniques, despite their increased diagnostic yield, did not influence diagnostic delay or survival in pancreatic and periampullary carcinoma.

Aged↗

PubMed1983

Effect of cadmium on the infection of Lactobacillus lactis by bacteriophage LL-H.

The infectivity of Lactobacillus lactis bacteriophage LL-H was shown to be calcium-dependent. Of 10 different divalent cations screened, cadmium specifically decreased the infectivity of LL-H in the presence of calcium. At 1 to 2 mM, CdCl2 resulted in a decrease of the burst size of about 2.5- to 4-fold. Cd2+ was shown to reduce specifically the level of total phage DNA synthesis, resulting in a reduced progeny phage yield. Moreover, Cd2+ had the most profound irreversible effect on progeny phage production between 20 and 60 min after LL-H infection. This paralleled the beginning of phage DNA synthesis. Possible modes of action of Cd2+ on phage DNA replication are discussed.

Bacteriophages↗

PubMedDate not supplied

Diagnostic accuracy of ultrasonography and C reactive protein concentration in acute cholecystitis: a prospective clinical study.

OBJECTIVE: To assess the value of ultrasonography together with C reactive protein concentration in predicting which patients with acute cholecystitis require immediate operation. DESIGN: Prospective study. SETTING: Oulu University Hospital, Finland. SUBJECTS: 129 consecutive patients admitted with suspected acute cholecystitis 1988-89. MAIN OUTCOME MEASURES: Correlation of ultrasonographic findings and C reactive protein concentrations with histological findings. RESULTS: Ultrasonography correctly classified 86 of 108 patients with acute cholecystitis (79%). When the findings were combined with those of increased concentrations of C reactive protein the accuracy rose to 105 of 108 (97%). Large increases in C reactive protein concentrations were associated with both infected bile and gangrene of the gall bladder. CONCLUSIONS: The combination of ultrasonography and measurement of C reactive protein concentration is recommended in the routine investigation of all patients with suspected acute cholecystitis. Serum C reactive protein concentrations should be monitored regularly to select those patients who require emergency operation.

Acute Disease↗

PubMedDate not supplied

Effect of cholecystectomy on plasma lipid and lipoprotein levels.

BACKGROUND/AIM: This study was designed to elucidate the effect of cholecystectomy, a common surgical procedure, on the concentrations of plasma lipids and lipoproteins. PATIENTS AND METHODS: 19 consecutive patient with symptomatic gallstone disease and emptying gallbladder, and 16 control patients (Nissen-Rosetti fundoplication) were studied. Cholesterol, triglyceride, and protein concentrations of various lipoproteins were analysed. RESULTS: Plasma total and LDL cholesterol levels were significantly reduced in cholecystectomy patients (p = 0.0048 and p=0.0239) at day 3 after the operation, the values returning to the preoperative level thereafter. In the control patients similar trends were observed for total and LDL cholesterol levels but these changes did not reach statistical significance. In cholecystectomy patients a significant increase was noticed in the very-low-density lipoprotein and intermediate density lipoprotein apoprotein B concentration three years after surgery (p= 0.0019 and p=0.0001). CONCLUSIONS: These minor changes in plasma lipoproteins following cholecystectomy are unlikely to have any importance in the development coronary heart disease. They indicate, however, altered enterohepatic metabolism of cholesterol after the removal of the gallbladder.

Adult↗

PubMedDate not supplied

Use of hypothermic circulatory arrest for cerebral protection during aortic surgery.

Optimal use of hypothermic circulatory arrest during aortic surgery requires understanding of its physiology. Research in laboratory animals and clinical observations have now documented that considerable residual cerebral metabolism remains with cooling to levels of 15-18 degrees C, especially if cooling intervals are short, reflected by persistent jugular venous desaturation. Cooling should be continued to below 15 degrees C if the duration of HCA is expected to exceed 20 minutes, and continued until jugular venous saturations exceed 95%. There is considerable laboratory evidence that even short durations of HCA are followed by a prolonged interval of increased cerebral vascular resistance during which cerebral metabolism is maintained at normal levels by markedly increased oxygen extraction. Clinical observations have now confirmed that considerable jugular venous desaturation is present in patients following HCA: it is more pronounced with prolonged HCA, and is still present as late as six hours after the start of rewarming. This reinforces the concept of a prolonged postoperative vulnerable interval following HCA, during which any compromise in oxygen delivery has the potential for producing cerebral injury. Several adjunctive measures have been shown to improve outcome following HCA. The simplest and most important is topical hypothermia: packing the head in ice during the interval of HCA. Retrograde cerebral perfusion (RCP) has also been shown to improve EEG recovery as well as histological and behavioral outcome in laboratory animals following prolonged HCA, but some of its effect may be secondary to its efficacy in keeping the brain cold, since RCP provides very low rates of flow and supports metabolism at a much lower level than antegrade perfusion at the same temperature. But despite the clear superiority of antegrade perfusion, and the documentation of some benefits of RCP in laboratory measures of cerebral protection, clinical results using RCP and ACP have not yet demonstrated the superiority of these methods over use of HCA alone, perhaps because these modalities are usually employed in patients with unusually high risk of neurological injury: those with dissection or with clot or atheroma in the aorta. Nevertheless, recent years have seen considerable reduction in mortality following aortic surgery, especially in older patients, and a trend toward a lower incidence of permanent neurologic dysfunction. The presence of preoperative rupture or hemodynamic compromise, and of clot or atheroma in the aorta, remain the most significant risk factors both for death and occurrence of stroke.

Animals↗