Active acromegaly enhances spontaneous parathyroid hormone pulsatility

In healthy subjects, parathyroid hormone (PTH) is secreted in a dual fashion, with low-amplitude and high-frequency pulses superimposed on tonic secretion. These 2 components of PTH secretion seem to have different effects on target organs. The aim of our study was to evaluate whether growth hormone excess in acromegaly may modify the spontaneous pulsatility of PTH. Five male patients with newly diagnosed active acromegaly and 8 healthy subjects were evaluated by 3-minute blood sampling for 6 hours. Plasma PTH concentrations were evaluated by multiparameter deconvolution analysis. Plasma PTH release profiles were also subjected to an approximate entropy (ApEn) estimate, which provides an ensemble measure of the serial regularity or orderliness of the release process. In acromegalic patients, baseline serum PTH values were not significantly different from those measured in the healthy subjects, as well as tonic PTH secretion rate, number of bursts, fractional pulsatile PTH secretion, and ApEn ratio. Conversely, PTH pulse half-duration was significantly longer in acromegalic patients vs healthy subjects (11.8+/-0.95 vs 6.9+/-1.6 minutes; P=.05), whereas PTH pulse mass showed a tendency (P=.06) to be significantly greater in acromegalic patients. These preliminary data suggest that growth hormone excess may affect PTH secretory dynamics in patients with acromegaly. Potentially negative bone effects of the modifications of PTH secretory pattern in acromegaly should be investigated.     

Subclinical hypothyroidism in HIV-infected subjects

OBJECTIVES: The correlation between subclinical hypothyroidism [thyroid stimulating hormone (TSH)>4 mIU/L with normal free triiodothyroxine and free thyroxine levels], HIV infection and HAART is still unclear. PATIENTS AND METHODS: To evaluate the predictive factors of subclinical hypothyroidism in an HIV-infected population, we identified three groups of subjects: G1, subjects on stable highly active antiretroviral therapy (HAART) (for at least 1 year) at baseline and at month 24 (n=97); G2, subjects naive at both baseline and month 24 (n=47); G3, subjects starting HAART at baseline (n=46). RESULTS: The three groups were comparable with respect to age, gender, body weight and prevalence of HCV infection. At baseline, subclinical hypothyroidism was detected in 14 subjects in G1 (14.4%), 5 in G2 (10.6%) and 4 in G3 (8.7%) (P=0.18) and these were excluded from the analysis. At month 24, 15 subjects had developed subclinical hypothyroidism: 4 in G1 (4.8%), 3 in G2 (7.1%) and 8 in G3 (19.0%). In the multivariable analysis, the higher increase in total cholesterol was predictive of subclinical hypothyroidism (RR: 1.53 for each additional 10 mg/dL, 95% CI 1.23-1.90; P<0.01); other variables, which were statistically significant in the univariate analysis, such as G3 group, body weight and higher increase in CD4+ cell count and in triglyceride serum levels were not confirmed to be associated with TSH alterations. CONCLUSIONS: The occurrence of subclinical hypothyroidism in HIV-positive patients seems to be related to the increase in total cholesterol serum levels occurring after HAART initiation. Thyroid function should be monitored in all HIV-infected subjects, especially in those starting HAART.     

Prevention of iatrogenic transmission of B19 infection: different approaches to detect, remove or inactivate virus contamination

Parvovirus B19 is a frequent contaminant of human blood and plasma derivatives and iatrogenic transmission of B19 infection has been shown to occur through the administration of contaminated products. Manufacturing procedures, generally used for removal or inactivation of enveloped viruses (HIV, HCV and HBV) are not always effective in the elimination of B19 virus. A certain risk of contamination remains for some plasma derivatives due to the high-titer viral load in the starting blood donations and the extreme heat resistance and small size of the virus. This review provides an update on the different approaches currently available to detect, remove or inactivate B19 virus in order to enhance the safety margins of plasma products. Nucleic acid amplification techniques are the methods of choice for the detection of viruses, due to their high specificity and sensitivity. NAT assays are beneficial tools for the identification of contaminated mini-pools or plasma pools and the quantification of B19 contamination. They may also be valuable for testing the removal of B19 virus during manufacturing: since the virus may not be completely inactivated or removed by chemical or physical treatments, residual B19 contamination should always be checked. Solvent-detergent treatments fail to destroy B19 capsids because of the absence of a lipid-envelope, and heat treatments (pasteurization and dry-heat methods) cannot guarantee a complete viral inactivation because of the variable heat sensitivity of the virus.     

Sensory, motor somatic, and autonomic neurons projecting to the porcine cremaster muscle

The location of sensory, somatic, and autonomic neurons projecting to the pig cremaster muscle (CM) was studied by means of the retrograde neuronal tracer Fast Blue (FB) technique. FB was randomly injected in the left CM of four impuberal pigs and serial sections of sensory and autonomic ganglia and spinal cord were examined under a fluorescence microscope. Additionally, some indications about the number and size of labeled neurons were given. Sensory pseudounipolar somata were located ipsilaterally in the L2-L6 and S1-S2 dorsal root ganglia, their total number ranging between 125 and 194, their mean diameter between 24 and 89 microm. Somatic multipolar motoneurons were located ipsilaterally in the L2-L4 neuromeres of the spinal cord, their total number ranging between 53 and 169, their mean diameter between 29 and 53 microm. Autonomic multipolar paravertebral ganglia neurons were located ipsilaterally from L1 to S4 and contralaterally from L2 to S2. Their total number ranged from 2,015 to 3,067 and their mean diameter between 25 and 55 microm. The multipolar caudal mesenteric ganglia neurons were located bilaterally, their total number ranging between 14 and 1,408 and their diameter from 22 to 39 microm. In two subjects only, multipolar neurons were also found ipsilaterally in the microganglia of pelvic plexus (2 and 13 neurons). Their mean diameter ranged between 28 and 54 microm. Our study documented that the CM-projecting neurons were located at different neural levels, with a predominance in the autonomic ganglia.     

Evaluation of artificial neural networks in the classification of primary oesophageal dysmotility

OBJECTIVE: Artificial neural networks (ANNs) can rapidly analyse large data sets and exploit complex mathematical relationships between variables. We investigated the feasibility of utilizing ANNs in the recognition and objective classification of primary oesophageal motor disorders, based on stationary oesophageal manometry recordings. MATERIAL AND METHODS: One hundred swallow sequences, including 80 that were representative of various oesophageal motor disorders and 20 of normal motility, were identified from 54 patients (34 F; median age 59 years). Two different ANN techniques were trained to recognize normal and abnormal swallow sequences using mathematical features of pressure wave patterns both with (ANN(+)) and without (ANN(-)) the inclusion of standard manometric criteria. The ANNs were cross-validated and their performances were compared to the diagnoses obtained by standard visual evaluation of the manometric data. RESULTS: Interestingly, ANN(-), rather than ANN(+), programs gave the best overall performance, correctly classifying >80% of swallow sequences (achalasia 100%, nutcracker oesophagus 100%, ineffective oesophageal motility 80%, diffuse oesophageal spasm 60%, normal motility 80%). The standard deviation of the distal oesophageal pressure and propagated pressure wave activity were the most influential variables in the ANN(-) and ANN(+) programs, respectively. CONCLUSIONS: ANNs represent a potentially important tool that can be used to improve the classification and diagnosis of primary oesophageal motility disorders.     

Epidemiology of FASD in a province in Italy: Prevalence and characteristics of children in a random sample of schools

BACKGROUND: Accurate estimates of the prevalence and characteristics of fetal alcohol syndrome (FAS) and fetal alcohol spectrum disorders (FASD) in a Western European population are lacking and are of particular interest in settings where the usual pattern of alcohol consumption is thought to be daily drinking with meals. To address these issues, an epidemiology study of FAS and other FASD was undertaken in Italian schools. METHODS: Primary schools (n = 25) in 2 health districts of the Lazio region were randomly selected and recruited for the study. Five hundred forty-three children, 50% of those enrolled in first-grade classes, received parental permission to participate in a 2-tiered, active case ascertainment screening process. Detailed evaluation of children selected in a preliminary screening phase was carried out on those who were small for height, weight, and head circumference and/or referred by teachers for suspected learning and behavioral problems. Detailed evaluation was carried out on each child's: (1) physical growth and dysmorphology, (2) psychological development and behavior, and (3) prenatal exposure to alcohol and other risk factors for FASD via maternal interviews. A group of 67 randomly selected children without FASD from the same classes was utilized as a comparison group. RESULTS: Using 2 denominators for prevalence estimation, a conservative one and a strict sample-based estimate, the prevalence of FAS in this province of Italy was 3.7 to 7.4 per 1,000 children. When cases of partial FAS (PFAS) and a case of alcohol-related neurodevelopmental deficits (ARND) were added to FAS cases, the rate of FASD was 20.3 to 40.5 per 1,000 and estimated at 35 per 1,000 overall or between 2.3 and 4.1% of all children. This exceeds previously published estimates of both FAS and FASD for the western world. Detailed data are presented that demonstrate the utility of the guidelines of the revised Institute of Medicine diagnostic criteria for FASD. Children with FASD are significantly more impaired/affected (p < 0.05) than randomly selected comparison children on all measures of growth deficiency, key facial features of FASD, overall dysmorphology scores, language comprehension, nonverbal IQ, and behavior. Maternal reports of current drinking were significantly higher for mothers of FASD children than comparison mothers, but reported rates of overall drinking during pregnancy were not significantly different. In contrast to expectations, daily drinking among mothers of the comparison group was not common. However, dysmorphology scores of the children were significantly correlated with drinking in the second and third trimesters, drinks per current drinking day, and current drinks per month. Finally, children with the physical features of FASD had lower IQs; nonverbal IQ was significantly correlated with head circumference and negatively correlated with overall dysmorphology score, smooth philtrum, and several other facial and physical anomalies characteristic of FAS. CONCLUSIONS: Using careful measures of ascertainment in a primary school setting, these results provide relatively high estimates of the prevalence of FASD and raise the question of whether FASD is more common in the western world than previously estimated.