Adjuvant activity of pollen grains

BACKGROUND

The induction of an immune response to a biologically inert soluble protein requires an adjuvant. Here we have examined whether intact grains of pollen display such adjuvant effect, accounting for the immunogenic activity of pollen protein allergens that are devoid of intrinsic pro-inflammatory/adjuvant property.

METHODS

Human monocyte-derived dendritic cells (DCs) were cultured with intact grains of grass or ragweed pollen for 48 h. The state of DCs maturation was analyzed by FACS and their cytokine production by ELISA. T cell priming activity of DCs was examined in co-cultures with naïve cord blood-derived CD4(+) T cells.

RESULTS

Contact with grains of pollen induced a distinct maturation program in immature DCs. Pollen up-regulated the expression of CD54, CD80, CD83, CD86, HLA-DR, CCR7, and CD40 on DCs. Moreover, CCR5 expression was up-regulated by pollen but suppressed by LPS. In sharp contrast to LPS-stimulated DCs, pollen-treated DCs did not produce cytokines [interleukin (IL)-10, IL-12, tumor necrosis factor (TNF)-alpha] but retained the ability to secrete high levels of these cytokines upon simulation with soluble CD40 ligand and interferon (IFN)-gamma. Pollen-primed DCs strongly stimulated the proliferation of allogeneic naïve CD4(+) T cells and promoted their development into effector cells producing high levels of IL-5 and IL-13 together with moderate levels of IFN-gamma and IL-4.

CONCLUSION

Intact grains of pollen induce activation and maturation of DCs in vitro. Similar mechanisms may be effective in vivo, suggesting that pollen grain is not only an allergen carrier but also acts as an adjuvant in the induction phase of the allergic immune response.

The endocannabinoid system in the brain of Carassius auratus and its possible role in the control of food intake

Cannabinoid receptors and the endocannabinoids anandamide and 2-arachidonoylglycerol have been suggested to regulate food intake in several animal phyla. Orthologs of the mammalian cannabinoid CB(1) and CB(2) receptors have been identified in fish. We investigated the presence of this endocannabinoid system in the brain of the goldfish Carassius auratus and its role in food consumption. CB(1)-like immunoreactivity was distributed throughout the goldfish brain. The prosencephalon showed strong CB(1)-like immunoreactivity in the telencephalon and the inferior lobes of the posterior hypothalamus. Endocannabinoids were detected in all brain regions of C. auratus and an anandamide-hydrolysing enzymatic activity with features similar to those of mammalian fatty acid amide hydrolase was found. Food deprivation for 24 h was accompanied by a significant increase of anandamide, but not 2-arachidonoylglycerol, levels only in the telencephalon. Anandamide caused a dose-dependent effect on food intake within 2 h of intraperitoneal administration to satiated fish and significantly enhanced or reduced food intake at low (1 pg/g body weight) or intermediate (10 pg/g) doses, respectively, the highest dose tested (100 pg/g) being inactive. We suggest that endocannabinoids might variously contribute to adaptive responses to food shortage in fish.

Primary cutaneous cryptococcal cellulitis secondary to insect bite in an immunosupressed patient after liver transplantation

Cutaneous cryptococcosis is usually a manifestation of disseminated disease, especially in immunosuppressed patients. Primary cutaneous cryptococcosis has also been described in some patients without evidence of systemic disease. Distinguishing between primary and secondary cutaneous cryptococcosis may be difficult as patients can be asymptomatic or cutaneous lesions may precede systemic involvement by some months. Features supporting primary disease are a history of cutaneous inoculation, and solitary superficial lesions on uncovered parts of the body. We present a liver transplant patient with cutaneous cryptococcal cellulitis subsequent to an insect bite, without systemic involvement and with excellent response to treatment with amphotericin B for 15 days and surgical debridement plus oral fluconazole for 3 months. In immunosupressed patients with cellulitis a cryptococcal infection must be excluded. If cutaneous cryptococcosis is diagnosed, systemic evaluation and prompt lengthy treatment are required.

Neuronal and inducible nitric oxide synthase expression in the rat cerebellum following portacaval anastomosis

In order to determine the role of neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) in the pathogenesis of experimental hepatic encephalopathy (HE), the expression of both was analyzed in the cerebellum of rats 1 month and 6 months after performing portacaval anastomosis (PCA). In control cerebella, nNOS immunoreactivity was mainly observed in the molecular layer (ML), whereas the Purkinje cells did not express nNOS. However, nNOS expression was detected in the Purkinje cells at 1 month after PCA, correlating with a decrease in nNOS expression in the ML--part of an overall reduction in cerebellar nNOS concentrations (as determined by Western blotting). At 6 months post-PCA, a significant increase in nNOS expression was observed in the ML, as well as increased nNOS immunoreactivity in the Purkinje cells. nNOS immunoreactivity was also observed in the Bergmann glial cells of PCA-treated rats. While no immunoreactivity for iNOS was seen in the cerebella of control rats, iNOS immunoreactivity was significantly induced in the cerebellum 1 month after PCA. In addition, the expression of iNOS was greater at 6 months than at 1 month post-PCA. Immunohistochemical analysis revealed this iNOS to be localized in the Purkinje cells and Bergmann glial cells. The induction of iNOS in astroglial cells has been associated with pathological conditions. Therefore, the iNOS expression observed in the Bergmann glial cells might play a role in the pathogenesis of HE, the harmful effects of PCA being caused by them via the production of excess nitric oxide. These results show that nNOS and iNOS are produced in the Purkinje cells and Bergmann glial cells following PCA, implicating nitric oxide in the pathology of HE.

Impact of lesion size on photodynamic therapy with verteporfin of predominantly classic lesions in age related macular degeneration

AIM

To determine if photodynamic therapy (PDT) outcomes are related to lesion size in patients with subfoveal predominantly classic choroidal neovascularisation (CNV) secondary to age related macular degeneration (AMD).

METHODS

According to greatest linear dimension (GLD) of the entire lesion determined with fluorescein angiography (FA) patients were divided into two groups. In the first group GLD was <3000 microm and in the second one GLD was 3000-5000 microm. All eyes were treated with standard PDT with the verteporfin protocol. The primary outcome was the proportion of eyes in both groups that did not show significant leakage in FA at the end of follow up. Secondary outcomes were changes in GLD and in best corrected visual acuity (BCVA).

RESULTS

64 patients (mean (SD) age, 76.7 (7.7) years; range 58-95 years) were recruited to participate in the study. All participants in the study completed the follow up time (mean 16.6 months). 24 patients (75%) in the group of smaller lesions (n = 32) compared with 15 patients (46.8%) in the group of larger lesions (n = 32) did not show significant leakage in FA at the end of follow up (p = 0.02). A GLD increase >1000 microm was recorded in nine eyes (28.1%) in the group of smaller lesions and in 16 eyes (50%) in the group of larger lesions (p = 0.07). 22 eyes (68.7%) in the group of smaller lesions compared with 19 eyes (59.3%) in the group of larger lesions lost less than three lines of vision (p = 0.06). Relevant side effects related to verteporfin therapy were not recorded, except for four patients (6.2%) with infusion related back pain.

CONCLUSIONS

These results suggest that lesion size at baseline may be a prognosis factor in PDT in patients with subfoveal predominantly classic CNV secondary to AMD. There are no relevant side effects or safety concerns derived from verteporfin therapy.

Down-regulation of astroglial proteins in the rat cerebellum after portacaval anastomosis

The effect of short-term portacaval anastomosis (PCA) on the expression of specific astroglial markers [glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS)] in the rat cerebellum was examined to determine the influences of PCA on astroglial cells. The results suggest that PCA directly interferes with astroglial cytoskeleton, as indicated by the irregular distribution and reduced expression of GFAP observed after 1 month. PCA also decreased GS immunoreactivity in the Bergmann glial processes of the molecular layer, as well as in astrocytes of the granule cell layer. It might also modulate glutamatergic nervous activity as GS expression was reduced in 1 month post-PCA brains. Moreover, the GFAP and GS levels in PCA-exposed rats were lower than in control rats. This might contribute to the appearance of encephalopathy by increasing extracellular glutamate and/or ammonia concentrations. These results show that short-term PCA interferes with astroglial protein expression, with both GFAP and GS levels falling in astroglial cells.

[Minimally invasive approach of Nuss for the correction of pectus excavatum]

Since December 1999 to November 2003, we treated 68 patients with pectus excavatum using the Nuss minimally invasive procedure. Their ages were between 6 and 24 years old, with a mean of 12 years. Average Haller index was 4.1. Lateral stabilisers were used in all the cases, in 28% of them, two stabilisers were used. Mean operative time was 70 minutes (range 40 to 120). A thoracic epidural catheter was used for postoperative analgesia in 87% of the cases, with a mean duration of 3 days. The most frequent early complication was residual pneumothorax, which resolved spontaneously in 24% of the cases. The average hospital stay was 5.7 days. 93% of patients had excellent, very good or good results, in 5% of the cases the results were fair, and 2% had poor results due to thoracic asimetry and/or sternal rotation. The Nuss minimally invasive procedure is a useful method for treatment of pectus excavatum's patients.

Prenatal cannabinoid exposure down- regulates glutamate transporter expressions (GLAST and EAAC1) in the rat cerebellum

Efficient reuptake of synaptically released glutamate is essential for preventing glutamate receptor overstimulation and neuronal death. Glutamate transporters play a vital role in removing extracellular glutamate from the synaptic cleft. This study analyzed the expression of the glial (GLAST) and neuronal (EAAC1) subtypes of glutamate transporter in the cerebellum of male and female offspring exposed pre- and postnatally to Delta9-tetrahydrocannabinol (THC, the main component of marijuana). Pregnant rats were administered saline or THC from gestational day 5 to postnatal day 20 (PD20). The expression of glutamate transporters was examined at PD20, PD30 and PD70 (10 and 50 days after THC withdrawal) to analyze the short- and long-term effects of prenatal THC exposure. The expression of the glutamate transporter GLAST in astroglial cells and EAAC1 in Purkinje neurons decreased in THC-exposed offspring compared to controls. This reduction was observed at all ages but mainly in males. Moreover, the glial glutamate transporter level in THC-exposed rats (quantified by Western blot) was lower than in control rats. These results suggest that THC exposure during cerebellar development may alter the glutamatergic system not only during the period of drug exposure but in the postnatal stage following withdrawal. The down-regulation reported here might reflect an abnormal maturation of the glutamatergic neuron-glia circuitry.

[Bronchial carcinoid tumor: a retrospective analysis of 62 surgically treated cases]

OBJECTIVE

To evaluate the results of surgical treatment for lung carcinoid tumor.

PATIENTS AND METHOD

The medical records of 62 patients who underwent surgical intervention for lung carcinoid tumor between May 1985 and October 2000 were reviewed.

RESULTS

Fifty-two patients had typical carcinoid tumors and 10 had atypical carcinoid tumors. Hilar or mediastinal lymph node metastases were present in 9 patients. Distant metastasis occurred in 5 patients and was significantly more frequent in those with the atypical carcinoid histological subtype. The overall survival rate at 15 years was 70%, with a mean survival rate of 138 (SD 11) months, calculated with the Kaplan-Meier method. We found no statistically significant correlation between smoking and the development of carcinoid tumors.

CONCLUSIONS

Although carcinoid tumors behave like low-grade malignant tumors, they should be treated in the same way as other malignant lung tumors. Curative surgical resection is the technique of choice whenever possible.

Characterization of allergens secreted by Anisakis simplex parasite: clinical relevance in comparison with somatic allergens

BACKGROUND

Diagnostic methods for the study of allergic reactions to Anisakis simplex (A.s.) based on whole-body extracts of the larva are clearly insufficient.

OBJECTIVES

To study the allergenicity of the proteins secreted by the parasite. Comparison with somatic antigens and determination of their clinical importance in allergic patients were also addressed.

METHODS

An excretory/secretory (E/S) extract was produced by culturing third-stage A.s. larvae. It was used to perform immediate skin tests and to determine specific IgE in 10 patients diagnosed with allergy to A.s. Both tests were compared with the results obtained with the whole-body extract (somatic (S)). The molecular weight (MW) of their allergens was determined by immunoblotting, and a single-blind placebo-controlled oral challenge with E/S proteins was performed. Finally, allergens' resistance to gastric pepsin and acid pH was explored.

RESULTS

A.s. larvae secreted allergens more potent than those present in the S extract. The skin prick test wheal area produced by E/S molecules and the absorbance obtained in the determination of specific IgE with these allergens (ELISA) were 5.8 times bigger than those obtained with S extract. MW allergens of 72 and 56 kDa in E/S extracts and those of 56, 48 and 43 kDa in S extract were recognized by more than 50% of the patients. Partial cross-reactivity between them was revealed by immunoblotting inhibition studies. Oral challenge with E/S extract (up to 479 microg) was negative in all the patients. Treatment of E/S proteins with gastric pepsin inhibited the binding of the E/S allergens for specific IgE. The acid pH did not affect the overall binding of IgE to E/S extract. It decreased by 15.23% and 19.96% at pH 4 and 2, but the difference was not statistically significant.

CONCLUSION

A.s. secretes allergens more potent than somatic antigens and should be used in the diagnostic procedures. These allergens are inactivated by the pepsin, which supports the theory that live larva is necessary to induce an allergic reaction in most of the patients.

[Video-assisted thoracoscopic sympathectomy for the treatment of facial flushing: ultrasonic scalpel versus diathermy]

OBJECTIVE

To evaluate the advantages of the ultrasonic scalpel compared to electrocoagulation in patients undergoing video-assisted thoracoscopic sympatholysis or sympathectomy for uncontrolled facial blushing.

METHODS

Two hundred bilateral video-assisted thoracoscopic procedures to interrupt transmission in the thoracic sympathetic nerve were performed in 100 patients with incapacitating facial blushing. In 2 cases, the video-assisted approach was chosen because of pleural symphysis. The mean age of patients was 34 years (range: 15 to 67). The sympathetic chain was interrupted from the lower portion of the first thoracic ganglion through the third.

RESULTS

All patients were discharged within 24 hours with the exception of one on whom an emergency thoracotomy had been performed. No complications were reported in the group in which a harmonic scalpel was used. One case of temporary Horner syndrome (4 months) and 3 cases of persistent chest pain (more than 2 weeks) were reported in the diathermy group. There were 9 cases of partial and asymptomatic pneumothorax that resolved without treatment or prolonged hospital stays.

CONCLUSION

Dissection of the sympathetic nerve is accomplished more reliably and with better visualization with the ultrasonic scalpel. Peripheral lesions in lung parenchyma and adjacent tissues (intercostal vessels and nerves) are avoided, as is Horner syndrome, which can be caused by dispersion of heat. Use of the ultrasonic scalpel would also lead to a lower incidence of postoperative neuralgia.

High prevalence of seropositivity to a major allergen of Anisakis simplex, Ani s 1, in dyspeptic patients

Finding evidence of anisakidosis requires invasive methods. We have developed a serological assay based on the detection of an immunoglobulin E (IgE) specifically directed against Ani s 1 protein, a major parasite allergen of Anisakis simplex, which has shown a high level of accuracy in the diagnosis of anisakidosis. We used this tool to determine the prevalence of anti-Ani s 1 IgE in dyspeptic patients and to investigate if its seropositivity could be related to epidemiological factors other than raw fish consumption. A total of 174 dyspeptic patients who submitted to upper digestive tract endoscopy were studied. Specific IgE against Ani s 1 was determined by immunoblotting. Quantitative information on smoking, alcohol consumption, and fish consumption as well as a history of gastric surgery was recorded. Twenty-four (13.8%) patients were seropositive for Ani s 1 protein. The seroprevalence of anti-Ani s 1 IgE increased with age in patients who were less than 62 years old (P = 0.047). Seropositivity to Ani s 1 was associated with the consumption of fish in vinegar (P < 0.001), raw fish (P = 0.001), and smoked fish (P = 0.007). There was no relationship between anti-Ani s 1 IgE seropositivity and the number of cigarettes smoked (P = 0.098) or alcohol intake (P = 0.179). Five patients had undergone previous gastric surgery, and three of those patients were seropositive for Ani s 1 (P = 0.019). In multivariate analysis, the consumption of fish in vinegar (P = 0.006), raw fish (P = 0.017), and smoked fish (P = 0.002) and a history of gastric surgery (P = 0.005) were independent factors associated with anti-Ani s 1 IgE detection. In conclusion, at present, anisakidosis might frequently be underdiagnosed, and it might have a clinical role in patients with upper dyspeptic symptoms. Uncooked-fish ingestion and previous gastric surgery were associated with seropositivity for Ani s 1 protein.

Expression of the mu-opioid receptor in the anterior pituitary gland is influenced by age and sex

To analyze whether opioids are able to modulate endocrine regulation by acting directly on rat pituitary cells, an immunohistochemical study of micro-opioid receptor expression in these cells was performed, with attention given to the analysis of potential age- and sex-related variations in receptor expression patterns. In both sexes, the micro-opioid receptor was detected in the pituitary pars distalis. However, significant age-related differences were observed. Both in male and female rats, the percentage of micro-opioid receptor-expressing cells decreased significantly from postnatal week one through the 24 months of our study. Interestingly, pituitary cells containing the micro-opioid receptor were significantly more numerous in male than in female, with exception of the pre-pubertal phase and old rats. According to two-way analysis of variance, the gender-related differences in micro-receptor expression were independent of age-related variations. Thus, without excluding hypothalamic actions, our results suggest that opioids may exert their endocrine function by acting directly on pituitary cells.

Involvement of 5-HT1A receptors in behavioural effects of the cannabinoid receptor agonist CP 55,940 in male rats

We have studied the possible interaction between the cannabinoid receptor agonist CP 55,940 (1 and 50 microg/kg) and the 5-HT1A receptor antagonist WAY 100635 (1 mg/kg) in the modulation of plus-maze and holeboard activity in Wistar adult male rats. In the plus-maze, the higher dose of CP 55,940 induced an anxiogenic-like effect, whereas the lower dose induced anxiolytic-like responses. The 5-HT1A antagonist, which was silent in this test, attenuated the anxiogenic, but not the anxiolytic, effect of CP 55,940. In the holeboard, the higher dose of CP 55,940 significantly decreased head-dipping duration, and WAY 100635, which did not affect exploratory head-dipping when administered alone, antagonized this effect. The administration of WAY 100635 significantly increased grooming behaviour, and this effect was inhibited by the two doses of CP 55,940, which did not exert any effect, per se, on this parameter. We provide the first evidence implicating 5-HT1A receptors in anxiety-related behavioural responses to a cannabinoid agonist.

[Prevalence and treatment of Gram-positive infections in internal medicine departments of Spanish hospitals: IGP Study]

This study aimed to identify therapeutic approaches and the tendencies of Gram-positive infections in Spanish hospitals in terms of prevalence, origin, location and etiology, as well as the characteristics of patients with these infections, their underlying illnesses, the severity and predisposing factors. We used statistical analysis to compare the results of two multicenter prevalence studies, the first from 1994-1995, and the second in 1998. We found a statistically significant decrease in the percentage of infected patients (45.8% vs. 32.8%; p <0.001), but an increase in infections by Gram-positive microorganisms (14.4% vs. 20.6%; p <0.001), which was reflected in the increased use of glycopeptides (17.1% vs. 31.2%; p = 0.002). The use of quinolones also increased. The most common underlying illnesses were heart disease and diabetes mellitus, and there was a reduction in the number of patients infected by HIV and in users of parenteral medication. The decrease in outpatient infections indicated that nosocomial infection was more frequent in the second study, in which the number of predisposing factors increased (52.3% vs. 79.2%; p <0.001), the most common of which were peripheral line, immobilization and a bladder catheter. Bacteremia was the most frequent infection, and there was a reduction in lower respiratory tract infections and an increase in skin and soft tissue infections. Staphylococcus aureus was the most frequently found microorganism and showed a significant increase in incidence (27.2% vs. 47.9%; p <0.001), whereas pneumococcus showed a decrease (15.0% vs. 5.2%; p = 0.012). It was concluded that despite the decrease in the percentage of infected patients and severely ill patients, there is an increase in Gram-positive infections, especially bacteremia, and in the use of more aggressive treatments. This may reflect the increase in resistant isolates.

Dopaminergic modulation of nNOS expression in the pituitary gland of male rat

Nitric oxide is an unconventional transmitter since it is not transported and released by exocytosis. In the pituitary gland, nitric oxide is locally synthesised by gonadotroph and folliculo-stellate cells. Dopamine, the principal central inhibitory signal in prolactin release, may exert its inhibitory effects by stimulation of nitric oxide production. However, the effects of dopaminergic modulation on nitric oxide-producing pituitary cells have not been analysed. Therefore, we examined the effects of intraventricular administration of the dopamine antagonist haloperidol (40 microg) on the pituitary expression of neuronal nitric oxide synthase (nNOS) in male adult rats. In untreated and control animals, nNOS-positive cells were very similar. Two types of nNOS-positive cells appeared in the pars distalis: round or polygonal cells and stellate cells. Although some isolated cells were found, the nNOS-positive cells commonly appeared grouped in clusters close to blood vessels. nNOS immunoreactivity appeared as a uniform staining throughout the cytoplasm, including cell prolongations. The number and size of nNOS-expressing cells in the pituitary gland decreased significantly after treatment with haloperidol (p<0.01). To evaluate the potential direct effect of dopamine on pituitary cells, pituitary monolayer cultures were treated with dopamine during a time-course of 12 h. Our in vitro studies revealed that dopamine increases the percentage of nNOS-positive cells and augments cellular area (p<0.05). These results demonstrate that: (1) treatment of rats in vivo with a dopamine antagonist significantly decreases expression of nNOS in the pituitary and (2) in vitro dopamine exerts a direct effect on pituitary cultures by increasing nNOS-positive cells. Thus, these findings suggest that dopamine may function as a physiological stimulator of nNOS expression in the rat pituitary gland.

Is Anisakis simplex responsible for chronic urticaria?

The association of chronic urticaria (CU) to parasitic infestations has been poorly studied. Recently, sensitization to the parasite larva Anisakis simplex has been described as the cause of acute urticaria and anaphylaxis. The aim of this work was to study the relationship between sensitization to A. simplex and CU. One hundred one patients with CU were studied. Data of possible contacts with A. simplex were collected and the usual CU study was performed. Furthermore, total and specific immunoglobulin E (IgE; Pharmacia CAP system IGE fluorescence enzyme immunoassay: CAP) to A. simplex, Ascaris lumbricoides, Echinococcus granulosus, and Toxocara canis were determined as well as skin-prick test with A. simplex and serology to E. granulosus. In accordance with the results of the CAP to A. simplex, the patients were divided into two groups, positive and negative, and, subsequently, subdivided into two other subgroups that were alternatively told to stop eating fish or seafood in their diet or to continue with their normal diet. Checkups were performed at 6, 12, and 18 months. Thirty-five percent of the patients had positive skin tests to A. simplex, and CAP to A. simplex was positive in 55%. The fish-eating habits, acute or chronic gastrointestinal disease, and the background of abdominal surgery were not related to the results of the CAP and/or skin test to A. simplex. A total of 21.8% of all the patients had detectable CAP to A. lumbricoides, 91% of whom had positive CAP to A. simplex. Three patients had specific IgE to T. canis and five patients had specific IgE to E. granulosus, in the absence of positive serology. All had specific IgE to A. simplex. Present infestation could not be proved in any of them. The clinical evolution and variations of CAP to A. simplex and of total IgE were not statistically different among the groups during the 6, 12, and 18 months of the study. The percentage of sensitization to A. simplex in patients with CU is elevated and determines the sensitization to other parasites because of cross-reactivity. We have not found any causal relationship between the presence of specific IgE to A. simplex and CU. The clinical importance of this finding in this disease is still undetermined.

Staphylococcus aureus bacteremic pneumonia: differences between community and nosocomial acquisition

OBJECTIVE

The aim of the study was to ascertain the clinical and epidemiologic characteristics of patients with nosocomial or community-acquired Staphylococcus aureus bacteremic pneumonia.

METHODS

A prospective study of 134 cases diagnosed between January 1990 and December 1995 was performed.

RESULTS

Fifty cases involved primary bacteremic pneumonias, of which 80% were nosocomial (the majority, 72%, in intensive care unit patients, of whom 57% were post-surgery). Of the 84 cases of secondary pneumonia, 36 were non-intravenous drug users (78% nosocomial, of whom 43% were in the intensive care unit), and 48 cases were intravenous drug users (98% community-acquired).

CONCLUSIONS

Nosocomial S. aureus bacteremic pneumonia was especially frequent in intensive care unit patients (68.1%), and community-acquired pneumonia in intravenous drug users (72.3%). In non-intravenous drug users, clinical outcome and mortality were similar for nosocomial and community-acquired pneumonia.

Postnatal differentiation of the immunohistochemical expression of aromatase P450 in the rat pituitary gland

At our laboratory, we have recently demonstrated the immunohistochemical expression of aromatase P450 in the pituitary glands of adult rats; this expression was seen to be sex-dependent. In order to determine whether the changes in the expression of the enzyme are related to changes in the gonadal sphere and whether the expression of the enzyme is related to the postnatal differentiation of hypophyseal cytology, in the present work we performed an immunohistochemical study in the rat pituitary gland from birth to old age. The immunohistochemical reaction to aromatase was evident and very generalized at 7 days after birth, with no large differences between the male and female animals. At 14 days the immunohistochemical reaction was decreased in the females, with no changes in the males. At 17 days, aromatase immunoreactivity in the pituitary glands of female rats was very weak whereas the males showed large numbers of reactive cells. These observations were further pronounced at 21 days and 2 months of life. At 24 months, the immunoreactivity found in the pituitary glands of the male rats had almost completely disappeared. Our results show that a postnatal differentiation in the immunohistochemical expression of aromatase occurs; this is tightly linked to sexual activity and is lost in old age. This suggests that hypophyseal aromatase would be related to the mechanisms of action of gonadal steroids on hypophyseal differentiation and secretion.

Private practitioners and tuberculosis control in the Philippines: strangers when they meet?

OBJECTIVE

To investigate the knowledge, attitudes and perspectives of the Filipino private physicians (PPs) on tuberculosis (TB) control issues in the Philippines and their implications for future governmental public health policies.

DESIGN

Cross-sectional telephone survey from June to October 2001.

PARTICIPANTS

In each of the 78 provinces of the Philippines we randomly selected 10 PPs from the provincial capital city, five PPs from an urban centre with more than 50,000 population, and one PP from 15 rural villages with <50,000 population, making a total of 30 PPs per province. These data were complemented with information from focus group discussions with health workers and policy makers working in TB control, and through personal interviews with PPs.

RESULTS

We interviewed 1355 (57.9%) of 2340 PPs identified. TB was diagnosed mainly through X-ray (87.9%) and usually treated with inappropriate regimens of anti-TB drugs (89.3%). The PPs did not follow-up their TB patients, did not trace the defaulters (97.9%) and did not identify contacts (91.4%). Only 24.2% knew the National Tuberculosis Programme (NTP) policies in depth. They defined the NTP's weakest points as diagnosis through sputum microscopy (59.2%) and the management of smear negative patients (29.7%). Most PPs were willing to collaborate with the NTP (83.3%) provided they were paid (38.4%). More than a half (51.5%) objected to obligatory reporting of new TB cases. The PPs based their success in attracting TB patients to their offices on confidentiality (46.1%) and on the kind treatment and flexibility given (43.7%).

CONCLUSIONS

Diagnosis and treatment of TB patients is a daily issue for the PPs in the Philippines, although they did not follow usually the NTP guidelines. The majority of the PPs wished to collaborate with the NTP provided they were paid.

Reduced glial fibrillary acidic protein and glutamine synthetase expression in astrocytes and Bergmann glial cells in the rat cerebellum caused by delta(9)-tetrahydrocannabinol administration during development

In this study we analyzed the responses of cerebellar astroglial cells to pre- and perinatal delta(9)-tetrahydrocannabinol (THC) exposure in three postnatal ages and both sexes. To determine whether THC during development directly modifies astroglial growth, this study investigated the effects of THC on astroglial morphological changes and on the expression of specific astroglial markers (glial fibrillary acidic protein: GFAP and glutamine synthetase: GS). Our results demonstrated that the administration of THC during development has deleterious effects on astroglial maturation in the cerebellum. These results also indicate that THC might interfere with astroglial differentiation in a way dependent on sex. The effect of cannabinoids on the development of cerebellar astroglial cells (astrocytes and Bergmann glial cells) is to reduce protein synthesis, since both GFAP and GS decreased in astroglial cells, not only during THC exposure but also in adult ages. Our data suggest that pre- and perinatal THC exposure directly interferes with astroglial maturation by disrupting normal cytoskeletal formation, as indicated by the irregular disposition of GFAP and the lower GFAP expression observed at all the ages studied. THC exposure during development may also modulate glutamatergic nervous activity since GS expression is reduced in THC-exposed brains. GS expression increased progressively after THC withdrawal, but GS expression had still not reached control values two months after THC withdrawal. This indicates that glutamate uptake is lower in glial cells exposed to THC, since GS expression is lower than in older controls. Consequently, glutamatergic neurotransmission may be affected by cannabinoid exposure during gestation. Therefore, cannabinoids exert developmental toxicity, at least on astroglial cells, which could contribute to fetal brain growth retardation.

Adaptive changes in the rat hippocampal glutamatergic neurotransmission are observed during long-term treatment with lorazepam

RATIONALE

Chronic treatment with benzodiazepines induces tolerance to most of their pharmacological effects. The best-studied neurochemical correlation to this phenomenon involves GABAergic adaptive changes. However, some compensation by excitatory neurotransmission could also be postulated.

OBJECTIVE

The aim of this work was to investigate the effect of chronic treatment with benzodiazepines on several parameters of hippocampal glutamatergic neurotransmission.

METHODS

Rats were injected (IP) with a single dose or daily doses (21 days) of 1 mg/kg lorazepam (LZ) or vehicle. Thirty minutes after the last dose, animals were killed and parameters were measured in the dissected hippocampi. We determined one presynaptic parameter, in vitro glutamate release induced by a 60 mM K(+) stimulus. [(3)H]MK-801 binding to postsynaptic NMDA receptors and the NMDA-stimulated efflux of cGMP were also evaluated.

RESULTS

While no changes were observed in any of the parameters after a single dose of the drug, we found an increase of 206% in in vitro glutamate release in chronically treated animals [two-way ANOVA: F(1,16)=6.22], together with an increment of 103% in the NMDA-stimulated cGMP efflux [two-way ANOVA: F(1,18)=14.05]. No changes either in K(D) or in B(max) values for [(3)H]MK-801 binding to hippocampal membranes were observed.

CONCLUSIONS

Taken together, these changes strongly suggest that a compensatory increase in the glutamatergic response develops in the hippocampus during chronic treatment with LZ. Our findings might indicate a contribution of glutamatergic mechanisms to the tolerance to hippocampal-mediated effects of LZ, such as amnesic and anticonvulsant activities.

[Video-assisted lobectomy through the auscultatory triangle for the surgical treatment of bronchopulmonary carcinoma. Preliminary experience]

OBJECTIVE

To describe a technique for video-assisted lobectomy through the auscultatory triangle (VALAT) and to assess early and medium-term outcome of the procedure in patients with non-small cell bronchopulmonary carcinoma in stage I.

PATIENTS AND METHOD

Between April 1999 and May 2002 we performed 25 VALAT procedures (24 lobectomies and 1 bilobectomy) in 25 patients with a mean age of 63.6 years (range 39-80).

RESULTS

No deaths occurred during or after surgery. Conversion to conventional thoracotomy was necessary in two cases. One patient was re-operated to resolve hemothorax and one developed a bronchopleural fistula that was treated by pleural drainage. The mean hospital stay was 6.3 days. Twenty-three patients have been disease-free throughout a mean follow-up period of 11.5 months (range 1-36). The two-year actuarial survival rate (Kaplan-Meier) was 93% 7%.

CONCLUSIONS

VALAT is a safe procedure that nevertheless requires specific training. The rate of complications was low in our patient series and mortality was nil. The outcome for patients with stage I bronchogenic carcinoma over a two-year follow-up period has been comparable to results obtained with conventional thoracotomy.

Daily variations in ceftriaxone pharmacokinetics in rats

The aim of this study was to determine whether the time of day ceftriaxone was administered modified its pharmacokinetics. Ceftriaxone was given intraperitoneally at either 0400, 1000, 1600, and 2200 h to Sprague-Dawley rats synchronized under a light-dark cycle of 12 h of light and 12 h of dark. Pharmacokinetic parameters were analyzed for the presence of a 24-h rhythm. Results showed significant daily variations (P < 0.05) in ceftriaxone clearance, with the highest values during the dark phase. It is concluded that time-dependent variations in ceftriaxone pharmacokinetics may affect the therapeutic efficacy of current once-daily dosing schedules.

Involvement of the kappa-opioid receptor in the anxiogenic-like effect of CP 55,940 in male rats

We have studied the possible interaction between three selective opioid-receptor antagonists, nor-binaltorphimine (NB: kappa) (5 mg/kg), cyprodime (CY: mu) (10 mg/kg) and naltrindole (NTI: delta) (1 mg/kg), and the cannabinoid receptor agonist CP 55,940, in the modulation of anxiety (plus-maze) and adrenocortical activity (serum corticosterone levels by radioimmunoassay) in male rats. The holeboard was used to evaluate motor activity and directed exploration. CP 55,940 (75 microg/kg, but not 10 microg/kg) induced an anxiogenic-like effect, which was antagonised by NB. The other effects of CP 55,940 (75 microg/kg), a decreased holeboard activity and stimulation of adrenocortical activity, were not antagonised by any of the three opioid receptor antagonists. CY and NTI, when administered alone, induced marked reductions in motor activity, anxiogenic-like effects and stimulation of adrenocortical activity. The selective kappa-opioid receptor antagonist NB, on its own, did not modify the level of anxiety but stimulated adrenocortical activity. We provide the first pharmacological evidence about the involvement of the kappa-opioid receptor in the anxiogenic-like effect of CP 55,940.

Dietary recommendations for patients allergic to Anisakis simplex

BACKGROUND

Anisakis simplex, a fish parasite, causes allergic urticaria, angioedema and anaphylactic shock through an IgE-mediated hypersensitivity mechanism. Consensus on the dietary recommendations that should be given to allergic patients is lacking. Our objective was to evaluate the usefulness of different types of diets in preventing further reactions in patients allergic to A. simplex.

METHODS

Twenty-eight adult patients, who had suffered an allergic episode caused by A. simplex were asked to follow one of the following three diets for a mean period of 13.16 months: a fish-free diet (diet 1; n = 19), a diet including fish frozen for more than 48 hours (diet 2; n = 9) and a diet with fresh fish (diet 3; n = 12). In all patients raw fish was excluded. Relapse rates and changes in total serum IgE and specific IgE to A. simplex were studied during the follow up.

RESULTS

During the 13-month follow-up none of the patients developed anaphylaxis. Urticaria symptoms were present in 5.8 %, 11.1 % (n.s) and 33.3 % (p = 0.016) of patients following diets 1, 2 and 3, respectively. Total IgE decreased by 64 % (p < 0.05), 48 % (p < 0.05) and 39.4 % (p < 0.05), respectively. Specific IgE to A. simplex decreased by 50.7 % (p < 0.05), 54.1 % (p < 0.05) and 23.6 % (p < 0.05) after diets 1, 2 and 3, respectively. No statistically significant differences were found among the groups in variations in total and specific IgE.

CONCLUSIONS

Patients allergic to A. simplex can eat fish that has been frozen at -20 C for 48 hours without risk of a severe allergic reaction. Long term decreases in specific and total IgE may not be good markers of eventual contact with A. simplex.

Bezafibrate-induced anaphylactic shock: unusual clinical presentation

We report a case of a patient who suffered generalized urticaria, chest tightness, wheezing, nausea, vomiting, hypotension, and loss of consciousness. Two hours earlier she had taken Eulitop Retard following lunch. She had tolerated all the implicated food after the reaction. Allergy evaluation revealed intense positive responses to intradermal tests with bezafibrate active component and Eulitop Retard (skin tests in control subjects were negative). Specific IgE tests (RAST) to Eulitop Retard were negative. An IgE mechanism is suggested to be responsible for this adverse reaction on the basis of the positive skin tets. The delayed onset (two hours) of this anaphylactic shock is unusual. Although infrequent, it may be caused by the specific pharmacokinetic characteristics of this drug, which is a slow releasing agent, mainly absorbed in the gut. The drug was taken just after lunch, and this concomitant food ingestion could also have produced a delay in gastric drainage and a retarded drug absorption. An IgE-mediated accelerated type reaction could also explain this delay. Apparently the patient reacted after the first contact to the drug, and the absence of a sensitization period is not usual in this type of immune reponse. Finally, we recommend the performance of prick and intradermal skin tests prior to any systemic challenge when allergic reactions to fibric acid derivatives are suspected.

Some comparative aspects of the pharmacokinetics of tylosin in buffaloes and cattle

The pharmacokinetics of tylosin were compared in cattle (Bos taurus) and buffaloes (Bubalus bubalis). Six animals received each a single dose of 10 mg/kg of tylosin tartrate by the intramuscular route. The serum concentration (Cmax) and the volume of distribution (Vd) presented significant differences between the two species. Cmax was 0.40 +/- 0.046 microg/ml for buffaloes and 0.64 +/- 0.068 microg/ml for cattle. Vd was 1.91 +/- 0.12 L/kg and 1.33 +/- 0.09 L/kg for buffaloes and cattle, respectively. However, as the present study did not show considerable differences in the pharmacokinetics of tylosin in buffaloes and cattle, similar dosage regimes of this drug can be recommended for both species.

Host genetic background at CCR5 chemokine receptor and vitamin D receptor loci and human immunodeficiency virus (HIV) type 1 disease progression among HIV-seropositive injection drug users

The effect of polymorphisms on genes encoding the CCR5 chemokine receptor and vitamin D receptor (VDR) in human immunodeficiency virus (HIV) type 1 disease progression was analyzed in a cohort of 185 HIV-seropositive injection drug users. Results confirmed a lack of association in patients with HIV disease between CCR5 wtDelta32 heterozygosity and a slow progression to AIDS and to a CD4 cell count <200 cells/microL. In contrast, a more rapid disease progression was associated with the VDR-BB genotype. A higher proportion of this genotype was found in patients with <200 CD4 cells/microL (P=.009; odds ratio [OR], 2.4; 95% confidence interval [CI], 1.3-4.7), as well as a faster progression both to AIDS (1993 CDC classification [CDC 1993]) and to a CD4 cell count <200 cells/microL. When the analysis was restricted to patients with a VDR-bb genetic background, patients with CCR5 wtDelta32 heterozygosity were overrepresented in CDC 1993 nonprogressors (P=.033; OR, 0.28; 95% CI, 0.08-0.92) and in those with >200 CD4 cells/microL (P=.062; OR, 0.26; 95% CI, 0.06-1.08). Also, patients with CCR5 wtDelta32 heterozygosity showed a slow progression both to AIDS CDC 1993 and to a CD4 cell count <200 cells/microL.

Useful tests on pleural fluid that distinguish transudates from exudates

We aimed to compare the classic Light's criteria with different testing strategies in an effort to improve the accuracy of pleural fluid (PF) categorization. Thirty-two patients with transudates and 140 with exudates on the basis of their clinical diagnosis were entered into the study. We examined the discriminative properties of 10 analytes in the identification of PF, both singly and in combination with an 'or' rule, to see which was best in distinguishing a transudate from an exudate. A combination of PF lactate dehydrogenase (LD) > 307 U/L (two-thirds of the upper limit of the serum LD reference range) with either PF cholesterol > 1.55 mmol/L or PF to serum protein ratio > 0.5 had a diagnostic accuracy similar to that of Light's criteria. We suggest the use of PF LD and cholesterol in combination as an alternative method for distinguishing pleural transudates from exudates. This test combination avoids the need for venepuncture and the simultaneous collection of a blood sample.