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Biomedical subjects

G Bona

Publications and source records attributed to G Bona.

At least 73 records · Page 4Linked to original sources
PubMed2000

Abdominal pain in children: a case of acalculous cholecystitis.

Acalculous cholecystitis is a rare disease in children. Most cases are associated with systemic infections or with autoimmune pathologies, but it may also occur without predisposing factors. A case observed in an otherwise healthy child is reported.

Abdominal Pain↗
PubMed1999

Early onset of gastric carcinoma and constitutional deletion of 18p.

We report on the association of a gastric carcinoma and a constitutional deletion of the short arm of chromosome 18 in a 14-year-old patient. The phenotype of the patient, including microcephaly, ptosis, micrognathia, tetralogy of Fallot, and mental retardation, fits well with previously reported cases of del(18p); she also showed a positive serology against Helicobacter pylori. The comparison of the alleles of polymorphic loci located on the short arm of chromosome 18 between the patient and her parents showed a maternal origin of the abnormal chromosome. Loss of heterozygosity (LOH) for loci located in the long arm of chromosome 18 is a frequent event in gastric carcinomas; it was observed in the tumoral mass of our patient and again, the alleles lost were of maternal origin. We postulate that the constitutional chromosomal abnormality may have favored the loss of the abnormal chromosome in some cells and that the loss of the deleted chromosome 18 (demonstrated by LOH for this chromosome in the tumoral mass) has been an early step in the pathogenesis of the gastric carcinoma of our patient with Helicobacter pylori infection acting as a cofactor.

Abnormalities, Multiple↗
PubMed1999

The impact of gender, puberty and body mass on reference values for urinary growth hormone (GH) excretion in normally growing non-obese and obese children.

OBJECTIVE: There is a lack of normal reference data on urinary GH (u-GH) excretion in children. We have investigated the impact of age, gender, pubertal development and body mass on reference values for u-GH excretion in normally growing non-obese and obese children. STUDY DESIGN: u-GH levels were evaluated in 1153 healthy normal children (aged 5-14) and in 684 obese children (body mass index, BMI: > 75th). u-GH levels (ng/8 h) were determined by ELISA as the mean value of three consecutive first morning voidings. RESULTS: Reference values (5-95th centile) for u-GH excretion in obese and non-obese children of both sexes are reported. In normal prepubertal children median u-GH levels were relatively stable and superimposable in the two sexes; subsequently, u-GH levels increased, reaching a peak value at 13 years in both sexes. Significant increments (P < 0.0001) in u-GH levels were shown at B2 for females and at G3 for males. A slight decline was evident at 14 years. In obese children, median u-GH concentrations were significantly lower than those recorded in normal children of prepubertal age and at all stages of puberty (except in females at B2), in spite of their comparable normal height. u-GH levels significantly increased at puberty also in obese children, although the pubertal rise was significantly (P < 0.001) lower (1.7-fold in both sexes) than that observed in normal children (2.5-fold in boys and 2.3-fold in girls). A multiple regression analysis showed that both chronological age (beta: 0.20), BMI (beta: - 0.11), gender (beta: - 0.04) and pubertal stage (beta: 0.25) contributed significantly to the physiological variation in u-GH levels (multiple R: 0.44, P < 0.00001). CONCLUSIONS: This study provides reference values for u-GH in normally growing non-obese and obese children, analysing the impact of gender, puberty and body mass on this parameter. In agreement with previous studies, which demonstrate blunted GH-responses to provocative stimuli and reduced nocturnal GH concentration, obese children have significantly lower u-GH levels than age-matched normal weight children, both before and during puberty.

Adolescent↗
PubMed1999

Practical applications of monitoring respiratory mechanics in newborn.

The authors evaluate the use of data supplied by common systems used to calculate respiratory mechanics in newborns in order to analyse the impact on the management of patients requiring assisted ventilation. Over the past few years, the sale of respiratory monitors that are easier to use and less complicated to manage, as well as being less expensive, has meant that nearly every Neonatal ICU can now determine, in real time, both the causes of respiratory insufficiency and the conditions of the newborn lung during mechanical ventilation to ensure improved adaptation of ventilatory support. Leaving aside a discussion of respiratory physiopathology and the principles regulating pulmonary ventilation, the authors focus on the practical effect that data normally supplied by this type of apparatus (airway pressure, inspiration and expiration airflow, expiration minute volume calculated for each respiratory act, tidal volume, system leaks and dynamic compliance) have on the ventilatory "setting" chosen by the clinician or on the diagnosis of some commonly found situations during neonatal mechanical ventilation. The experience described concerns the impression of clinicians, skilled in the management of patients receiving conventional artificial ventilation but not so attracted by respiratory physiopathology, regarding the value of such instruments. The unanimous positive opinion confirms the thesis whereby respiratory monitoring can certainly help the neonatologist make a real time evaluation of both the causes leading to respiratory failure and the effect on the lung of any therapeutic decisions.

Equipment Design↗
PubMed1999

IGF-1 and IGFBP in congenital and acquired hypothyroidism after long-term replacement treatment.

BACKGROUND: Thyroid hormones are involved in the regulation of the GH/IGF axis. Hypothyroidism is associated with a reduction in GH pulsatility and in GH-response to stimulatory tests. In hypothyroidism, serum levels of IGF-1 and IGFBP-3 fall and these changes are reversed after short term replacement with L-T4. This study was undertaken to determine the effect of long term replacement therapy with T4 in IGF-1 and IGFBP-3 serum levels. METHODS: The study included 12 patients affected with hypothyroidism and in replacement treatment with T4. They were divided into 3 groups according to age at the beginning of treatment. Group A consisted of 4 pre-pubertal subjects with Congenital Hypothyroidism (CH) diagnosed with neonatal screening, where T4 treatment was started within 15 days of life. Group B consisted of 5 young adults where CH was clinically diagnosed at the median age of 6 months and replacement therapy started at this age. Group C consisted of 3 subjects affected with hypothyroidism secondary to thyroiditis where diagnosis and replacement treatment were delayed at age 11, 12 and 14 respectively. All subjects were matched with a control of the same age, sex, weight and pubertal stage. RESULTS: FT3, FT4 and TSH were in the normal range both in patients and in controls. No correlation was found between FT3 or FT4 and IGF-1 or IGFBP-3 serum levels. IGF-1 serum levels in group A (198 +/- 122 ng/ml) were significantly lower than that in group B (624 +/- 105, p < 0.001) and in group C (649 +/- 98, p = 0.003). IGFBP-3 serum levels in group A (1.98 +/- 0.56 micrograms/ml) were significantly lower than in group B (3.65 +/- 1.10, p = 0.03) and in group C (4.13 +/- 0.49, p = 0.003). The increase in IGF-1 and IGFBP-3 levels was seen also in control groups B and C when compared with control group A. IGF-1 and IGFBP-3 were positively correlated with age both in patients and in controls. A linear correlation was found between IGF-1 and IGFBP-3 which was positive for controls (r = 0.946, p < 0.001) and patient group A and B (r = 0.839, p = 0.005) but tended to be negative for patient group C (r = -0.65, n.s.). CONCLUSIONS: Our data demonstrate that long term replacement therapy in children with hypothyroidism is associated with a physiological increase in IGF-1 and IGFBP-3. The positive correlation between IGF-1 and IGFBP-3 levels in group A and B confirm the efficacy of long term replacement treatment on the IGF-1/BP-3 axis in pre- and post-pubertal patients treated for CH. However, this correlation tended to be negative in patients with hypothyroidism secondary to thyroiditis, suggesting that the cause of thyroid insufficiency and/or the age at the beginning of replacement therapy may have a role in the post-pubertal hormonal status in IGF-1 and IGFBP-3 balance.

Adolescent↗
PubMed1998

Haemodynamic effects of the intravenous administration of growth hormone in anaesthetized pigs.

Administration of growth hormone in humans has been reported variably to affect arterial blood pressure and ventricular contractility. The present study was undertaken in anaesthetized pigs to establish whether increases in the blood levels of growth hormone primarily affect haemodynamic variables and to determine the mechanisms involved. In pigs anaesthetized with pentobarbitone sodium, left circumflex or anterior descending coronary blood flow was measured with an electromagnetic flowmeter. In a first group of 23 pigs, growth hormone administration (0.05 IU kg-1 i.v.) increased aortic blood pressure and reduced coronary blood flow when heart rate and aortic blood pressure were held constant. These responses were augmented by graded increases in plasma levels of growth hormone. The mechanisms of the above responses were studied in a second group of 29 pigs and involved beta2-adrenergic receptors since they were abolished by propranolol or butoxamine but not by atropine, phentolamine or atenolol. The present study showed that administration of growth hormone in anaesthetized pigs primarily increased aortic blood pressure and vasoconstricted the coronary circulation. The mechanisms of these responses involved beta2-adrenoceptor effects.

Adjuvants, Anesthesia↗
PubMed1998

Neonatal transient hypothyroidism: aetiological study. Italian Collaborative Study on Transient Hypothyroidism.

AIMS: To define the aetiology of neonatal transient hypothyroidism (NTH) and recommend preventive measures. METHODS: Maternal and perinatal clinical data on the use of antiseptics, drugs, and contrast agents containing iodine were collected from 40 subjects. Thyroid stimulating hormone (TSH), free thyroxine (FT4), thyroxine (T4), thyroglobulin (TG), TSH receptor antibodies, thyroid peroxidase antibodies and urinary iodine were measured in random neonatal samples. In the mothers with known or suspected thyroid disorders, TSH, FT4, TSH receptor antibodies and thyroid peroxidase antibodies were also measured. RESULTS: The NTH aetiology was identified in 85% of cases. More than 50% of the babies with transient hypothyroidism had been exposed to iodine; maternal transfer of antibodies had occurred in a third of them. CONCLUSIONS: It is suggested that the practice of using iodine containing disinfectants should be withdrawn, and chlorhexidine substituted instead; that pregnant women should be advised of the adverse effects of using iodine products; and that thyroid function should be monitored whenever iodine is used.

Adult↗
PubMed1998

[Prevalence of goiter and urine iodine in a school population in an area of the Bolognese Apennines].

We evaluated goiter prevalence and urinary iodine excretion (UIE) in schoolchildren living in three villages of the Appennines in the Bologna district-Castel d'Aiano (CA), Gaggio Montano (GM) and Pietracolora (PC). 175 age-matched schoolchildren living in the urban area of Bologna were considered as control group. In the control area the presence of goiter was documented in 11 out of 175 subjects (6.3%). In the mountain area the presence of goiter was documented in 42 out of 233 subjects (18%) (p < 0.0001 vs control area). In the urban control area the UIE was 159 micrograms/l (median; range 19-298). In the mountain area the UIE was 119 micrograms/l (median; range 10-286) (p < 0.001 vs control area). We observed the highest prevalence of goiter and UIE levels < 100 micrograms/l only in the village of PC, which is still characterized by geographical isolation and rural economy.

Biomarkers↗
PubMed1998

Detoxification process for glutaraldehyde-treated bovine pericardium: biological, chemical and mechanical characterization.

BACKGROUND AND AIMS OF THE STUDY: Glutaraldehyde cross-linked bovine pericardium was post-treated with homocysteic acid in order to bond unreacted glutaraldehyde groups, and preserved in aldehyde-free solution to reduce the toxicity and calcification potential of the tanned tissue. The study aim was to verify the efficacy and preservation of chemical and mechanical properties of pericardial tissue treated in this way. METHODS: Detoxification efficacy was tested by measuring free aldehyde groups and by in vitro cultivation of human endothelial cells on pericardial samples. Material stability tests included mechanical characterization, shrink temperature measurement, pronase digestion resistance and amino acid analysis after acid hydrolysis. The effect of treatment on fatigue resistance was evaluated by monitoring changes in permeability and compliance caused by 15 x 10(6) cycles of pulsatile stress. RESULTS: Detoxified samples showed negligible glutaraldehyde residues and significantly improved endothelial cell proliferation compared with conventionally treated samples. Chemical and mechanical properties were similar in detoxified and glutaraldehyde-treated samples. Tissue fatigue behavior was not modified by homocysteic acid treatment. CONCLUSION: Homocysteic acid treatment effectively reduces toxicity but does not affect the stability of glutaraldehyde cross-linked pericardium.

Adult↗
PubMed1998

IGF-1 and IGFBP-3 in congenital and acquired hypothyroidism after long-term replacement treatment.

BACKGROUND: Thyroid hormones are involved in the regulation of the GH/IGF axis. Hypothyroidism is associated with a reduction in GH pulsatility and in GH-response to stimulatory tests. In hypothyroidism, serum levels of IGF-I and IGFBP-3 fall and these changes are reserved after short-term replacement with L-T4. This study was undertaken to determine the effect of long-term replacement therapy with T4 in IGF-1 and IGFBP-3 serum levels. METHODS: The study included 12 patients affected with hypothyroidism and in replacement treatment with T4. They were divided into 3 groups according to age at the beginning of treatment. Group A consisted of 4 pre-pubertal subjects with Congenital Hypothyroidism (CH) diagnosed with neonatal screening, where T4 treatment was started within 15 days of life. Group B consisted of 5 young adults where CH was clinically diagnosed at the median age of 6 months and replacement therapy started at this age. Group C consisted of 3 subjects affected with hypothyroidism secondary to thyroiditis where diagnosis and replacement treatment were delayed at age 11, 12 and 14 respectively. All subjects were matched with a control of the same age, sex, weight and pubertal stage. RESULTS: FT3, FT4 and TSH were in the normal range both in patients and in controls. No correlation was found between FT3 or FT4 and IGF-1 or IGFBP-3 serum levels. IGF-1 serum levels in group A (198 +/- 122 ng/ml) were significantly lower than that in group B (624 +/- 105, p < 0.001) and in group C (649 +/- 98, p=0.003). IGFBP-3 serum levels in group A (1.98 +/- 0.56 microgram/ml) were significantly lower than in group B (3.65 +/- 1.10, p=0.03) and in group C (4.13 +/- 0.49, p=0.003). The increase of IGF-1 and IGFBP-3 levels was seen also in control groups B and C when compared with control group A. IGF-1 and IGFBP-3 were positively correlated with age both in patients and in controls. A linear correlation was found between IGF-1 and IGFBP-3 which was positive for controls (r=0.946, p < 0.001) and patient group A and B (r=0.839, p = 0.005) but tended to be negative for patient group C (r=0.65, n.s.). CONCLUSIONS: : Our data demonstrate that long-term replacement therapy in children with hypothyroidism is associated with a physiological increase in IGF-1 and IGFBP-3. The positive correlation between IGF-1 and IGFBP-3 levels in group A and B confirm the efficacy of long-term replacement treatment on the IGF-1/BP-3 axis in pre- and post-pubertal patients treated for CH. However, this correlation tended to be negative in patients with hypothyroidism secondary to thyroiditis, suggesting that the cause of thyroid insufficiency and/or the age at the beginning of replacement therapy may have a role in the post-pubertal hormonal status in IGF-1 and IGFBP-3 balance.

Adolescent↗
PubMed1998

[Sepsis caused by Haemophilus influenzae type B with septic arthritis in an infant].

Septic arthritis is a serious pyogenic infection that may lead to permanent orthopedic sequelae. Infants represent the most of the cases. It usually develops as a result of bacterial seeding into the capillary-rich synovium in the course of a bacteremic episode. Etiology changes according to different ages; in children after the neonatal period but younger than 24 months, Haemophilus influenzae is the most frequent causative organism. A case of sepsis due to Haemophilus influenzae type b (Hib) with septic arthritis in a patient 3 months old, is reported. The child was admitted to the hospital with a very high temperature (39 degrees C) for five days. His right wrist and ankle appeared swelling and hyperemic. He was affected by congenital cardiopathy from birth. He was not immunizated against Hib. The blood colture was positive for Hib. The leukocyte count was 21,400 cell/mm3 with 55% of polymorphonuclear cells. During the second day of recovery, the patient was transfused, because of the very low value of hemoglobin (5.2 g/dl). The child was treated with netilmycina and ceftriaxone for 15 days. The temperature fell in two days. The articular pathology resolved in nearly ten days. The case reported confirms the importance of septic arthritis as a pathology that necessarily requires an early diagnosis and treatment. The Haemophilus influenzae vaccine, is recommended especially in immunocompromised or cardiopathic subjects and before the age of 2 years.

Arthritis, Infectious↗