Association of tau gene polymorphism with Parkinson's disease

We investigated the segregation of the dinucleotide GT repeat polymorphism in the intron between exons 9 and 10 of the tau gene in 300 patients with Parkinson's disease (PD) and in 197 normal controls. The A3 allele was more frequent in cases than in controls (30% versus 16%, p<0.001), and individuals carrying at least one A3 allele in their genotype had an increased risk of developing PD (odds ratio 2.78, 95% confidence interval 1.81-4.29). No significant differences were found between patients by considering the age at onset and the presence of family history or dementia. Our findings suggest a possible involvement of the tau gene in the pathogenesis of PD.

NACP-REP1 polymorphism is not involved in Parkinson's disease: a case-control study in a population sample from southern Italy

Contradictory evidence has been reported on the role of the polymorphic mixed dinucleotide repeat (NACP-REP1) of the alpha-synuclein gene as a risk factor for sporadic Parkinson's disease (PD). In the present study we genotyped the NACP-REP1 polymorphism in 189 PD patients from southern Italy and 182 healthy control subjects. We failed to demonstrate an association of any NACP-REP1 allele with PD.

GABA(B) receptor 1 polymorphism (G1465A) is associated with temporal lobe epilepsy

BACKGROUND

Dysfunction of gamma-aminobutyric acid (GABA) (B) receptors has been implicated in the pathogenesis of temporal lobe epilepsy (TLE).

OBJECTIVE

To evaluate the genetic contribution of cloned human GABA(B) receptors to TLE.

METHODS

The authors genotyped 141 patients (78 women and 63 men; mean age = 49.1 +/- 18.0 years) with nonlesional TLE and 372 age- and sex-matched normal individuals for the known polymorphism G1465A in the human GABA(B) receptor 1 [GABA(B[1])] gene.

RESULTS

There was a highly significant overrepresentation of the G1465A heterozygote in patients with TLE compared with controls. The A/G genotype was found in 17% of the 141 patients with TLE and in only 0.5% of the 372 controls (p < 0.0001). The authors also found that patients carrying the A allele had a significantly higher risk (p = 0.003, OR = 6.47, 95% CI = 2.02 to 20.76) of developing drug-resistant TLE. Furthermore, the age at onset of seizures tended to be lower in patients with A/G genotype, but the difference was not significant.

CONCLUSIONS

The results of this study indicate that the GABA(B[1]) polymorphism (G1465A) confers a highly increased susceptibility to TLE. Moreover, it seems to influence the severity of this common epileptic disorder.

Obesity does not induce abnormal CSF pressure in subjects with normal cerebral MR venography

Obesity has been shown to increase lumbar CSF pressure in healthy subjects. The authors studied lumbar CSF opening pressure in 18 obese, 33 overweight, and 49 nonoverweight subjects with normal MRI and MR venography (MRV) of the brain. No subject had a CSF pressure above 200 mm H2O. Obesity does not cause abnormal CSF pressure in subjects with normal MRV. Individuals with a CSF pressure higher than 200 mm H2O should undergo MRV to exclude cerebral venous thrombosis.

Conservative medical therapy of infections following osteosynthesis: a retrospective analysis of a six-year experience

The conventional therapeutic approach to bone infection associated with osteosynthesis is based on the idea that microbial eradication is most readily achieved by removal of the foreign material together with adequate antimicrobial therapy. This strategy usually requires implantation of external fixation devices with additional discomfort to the patient. We report our experience with conservative medical and antimicrobial therapy without removal of the osteosynthesis until adequate bone callus deposition is documented by bone radiography scan. Twenty patients with infections associated with intramedullary nailing (9 patients), screws and plate (9 patients) or screws (2 patients) were treated between 1995 to 2000. Osteosynthesis implantation sites were tibia (7 patients), femur (6 patients), femur and tibia (1 patient), humerus (1 patient), others (5 patients). Diagnosis of infection was based on clinical-microbiological evidence and confirmed by 99Tc-labeled leukocyte scan studies. Offending pathogens were Staphylococcus aureus 17 cases, Staphylococcus aureus + Escherichia coli, Staphylococcus epidermidis, unknown, 1 case each. Most infections were initially treated with intravenous or intramuscular teicoplanin +/- ciprofloxacin or rifampin followed by oral antimicrobial therapy usually with ciprofloxacin or minocycline plus rifampin. Mean duration of antimicrobial therapy was 27.7 weeks (range 12-64 weeks). All patients (100%) were cured, and none complained of side-effects requiring antibiotic therapy discontinuation. We conclude that conservative medical therapy is feasible for osteosynthesis-associated bone infection.

Blood and intrauterine leukocyte profile and function in dairy cows that spontaneously recovered from postpartum endometritis

The profile and function of blood and uterine leukocytes were evaluated in 14 dairy cows that spontaneously recovered from postpartum endometritis (mild, n=6 and heavy, n=8; general health not affected). From a minimum of 2 weeks before parturition until 6 weeks postpartum, blood samples were obtained twice weekly for leukocyte counts and leukogram determination and once weekly for flow cytometry assessment of polimorphonuclear neutrophils (PMN) phagocytic capacity and oxidative burst activity. Uterine fluid-stained smears, obtained twice weekly from parturition until fluid was present in the uterus, were used for determination of the percentage of PMN, of phagocytizing PMN (phago-PMN) and of the mean number of phagocyted bacteria per phagocytizing PMN (phagocytic index; PI). Uterine swabs were obtained twice weekly from parturition until 35 days postpartum for bacteriological examination. The time of endometritis diagnosis was similar in cows with mild or heavy endometritis but the latter cows had a significantly longer persistence of the infection and of the isolation of Gram-negative anaerobes from the uterus. However, the effect of group (mild versus heavy) was not significant for all the blood and uterine parameters analysed. The effect of sampling day (within group effect) was significant (p<0.01 to p<0.00001) for all parameters, except for the blood monocyte count and the blood PMN phagocytic capacity, in which only a tendency for significance was observed (p<0.1). The effect of the interaction group x sampling day was significant only for the blood monocyte count. The phago-PMN and the PI were significantly correlated (r=0.70, p<0.001). A significant correlation was also observed between the uterine fluid phago-PMN and the blood PMN oxidative burst activity (r=-0.41, p<0.05). At the spontaneous recovery, the blood PMN oxidative burst activity was significantly higher (p<0.05) and the percentage of intrauterine phago-PMN and the PI were significantly lower (p<0.001 and p<0.01, respectively) than at diagnosis of endometritis. These results suggest that a decrease in blood PMN oxidative burst activity until the first week postpartum could be associated with an increased susceptibility to early postpartum endometritis. The later increase in this parameter as well as the increase in the intrauterine fluid phago-PMN and PI, might favour the spontaneous resolution of endometritis.

Pulsed laser deposition of pseudowollastonite coatings

Pseudowollastonite (alpha-CaSiO3) is a bioactive ceramic material that induces direct bone growth. A process to obtain pseudowollastonite coatings that may be applied to implants is described and evaluated in this work. The coatings were first deposited on titanium alloy by laser ablation with a pulsed Nd:YAG laser tripled in frequency. After deposition, they were submitted to a soft laser treatment with a continuous wave Nd:YAG infrared laser. Coatings were characterised by X-ray diffractometry, Raman spectroscopy, scanning electron microscopy and energy dispersive spectroscopy before and after the laser treatment. As-deposited coatings are composed of pseudowollastonite and amorphous material. They have a porous structure of gathered grains and poor cohesion. After the laser treatment the coatings crystallinity and cohesion are improved. The laser treatment also makes the coatings dense and well adhered to the substrate. Therefore, this two-step process has been demonstrated as a valuable method to coat titanium implants with pseudowollastonite.

Plasminogen activator production in a rat model of Pneumocystis carinii pneumonia

Several studies have indicated that the serine protease urokinase-plasminogen-activator (uPA) is an important factor in host defense against pulmonary pathogens. To gain a better insight into the role of uPA in Pneumocystis carinii (P. carinii) pneumonia (PCP), we evaluated PA production in alveolar macrophages (AMs) obtained from rats with steroid-induced PCP. Treatment with cortisone acetate favored PCP in 91% of rats. In the bronchoalveolar lavage (BAL) samples of immunosuppressed rats both with and without PCP, we observed a decrease in uPA activity as well as a decrease in cell number. Urokinase-PA production by AMs was reduced in rats treated with cortisone alone. However, an increase in cell-associated uPA was observed in rats with PCP. This increase appears to be produced in response to P carinii infection. In fact, when AMs obtained from untreated healthy or immunosuppressed uninfected rats were challenged with P carinii, a significant increase in PA activity in cell lysates was observed, though a lower response was obtained in cortisone-treated animals. Our results suggest that healthy AMs respond to the presence of P carinii with an increase in uPA production and that this response in immunodepressed rat-AMs is partially impaired.

[Popliteal (Baker's) cyst in a patient with tubercular arthritis. Report of a case and review of the literature]

The Baker's cyst is a distension of the bursa subtendinea and is caused by noninfectious knee effusion secondary to arthrosis, meniscal tears, trauma, rheumatoid arthritis, gout, or any other form of sinovitis, like rheumatoid arthritis. An infected popliteal cyst is much less common; tuberculous arthritis is exceptional, in fact only four cases are described in literature. Herein we describe an additional tbc case of a 51 years old men, who has been initially treated with cytostatic and corticosteroid agents, for a suspected rheumatoid arthritis. The review of the literature suggests the importance of a correct approach to the diagnosis, based on the analysis and culture of the synovial fluid, because delays latency of effective antibiotic therapy can result in permanent joint damage that invalidate the patients.

Arthritis as a rare side effect of phenytoin therapy

Anticonvulsant hypersensitivity syndrome is an uncommon side effect of phenytoin. It is characterized by fever, skin reactions, lymphadenopathy, and severe multiorgan involvement. Atypical clinical features have rarely been described. We observed a unique case of anticonvulsant hypersensitivity syndrome in a 77-year-old woman in whom fever and monoarthritis were the main clinical features. Symptoms dramatically subsided after phenytoin withdrawal.

Expansion of the antigenic repertoire of a single T cell receptor upon T cell activation

Activated T cells and their naive precursors display different functional avidities for peptide/MHC, but are thought to have identical antigenic repertoires. We show that, following activation with a cognate mimotope (NRP), diabetogenic CD8(+) T cells expressing a single TCR (8.3) respond vigorously to numerous peptide analogs of NRP that were unable to elicit any responses from naive 8.3-CD8(+) T cells, even at high concentrations. The NRP-reactive, in vivo activated CD8(+) cells arising in pancreatic islets of nonobese diabetic mice are similarly promiscuous for peptide/MHC, and paradoxically this promiscuity expands as the aviditiy of the T cell population for NRP/MHC increases with age. Thus, activation and avidity maturation of T lymphocyte populations can lead to dramatic expansions in the range of peptides that elicit functional T cell responses.

CD4(+) T-lymphocytopenia and Pneumocystis carinii pneumonia in a patient with miliary tuberculosis

We report a case of miliary tuberculosis (MTB) occurring after extracorporeal shock-wave lithotripsy in a 51-year-old man. The MTB was complicated by pancytopenia and CD4(+) T-lymphocytopenia, which was responsible for Pneumocystis carinii pneumonia. Hematological parameters returned to normal in response to antituberculous treatment.

High-dose progestins for the treatment of cancer anorexia-cachexia syndrome: a systematic review of randomised clinical trials

BACKGROUND

The aim of the present study was to summarise evidence from scientific studies on cancer anorexia-cachexia syndrome in order to assess and highlight the efficacy of high-dose progestins (megestrol acetate and medroxyprogesterone acetate) compared with placebo in patients with hormone-independent tumors.

MATERIALS AND METHODS

A systematic review of published randomised clinical trials was carried out by an extensive electronic and hand search through databases, relevant journals and books, congress, proceedings, reference lists, without any language or year of publication restriction. The research was conducted by two independent operators who collected the data in a form specifically designed for this review. Among the several possible outcomes, appetite and body weight were chosen.

RESULTS

Fifteen randomised clinical trials (more than 2000 patients) were retrieved for the review. There was a statistically significant advantage for high-dose progestins as regards improved appetite: pooled odds ratio (OR) = 4.23, 95% confidence interval (CI): 2.53-7.04. Although the effect of high-dose progestins on body weight was less impressive, statistical significance was also reached for this outcome: pooled OR = 2.66, 95% CI: 1.80-3.92. Treatment morbidity was very low, due to the brief period of the treatment in most of the studies.

CONCLUSIONS

The effects of high-dose progestins on appetite and body weight were clearly demonstrated. However, further studies are undoubtedly warranted to investigate other aspects of progestin activity, especially as regards dosage, duration and timing with best therapeutic index.

Progression of autoimmune diabetes driven by avidity maturation of a T-cell population

For unknown reasons, autoimmune diseases such as type 1 diabetes develop after prolonged periods of inflammation of mononuclear cells in target tissues. Here we show that progression of pancreatic islet inflammation to overt diabetes in nonobese diabetic (NOD) mice is driven by the 'avidity maturation' of a prevailing, pancreatic beta-cell-specific T-lymphocyte population carrying the CD8 antigen. This T-lymphocyte population recognizes two related peptides (NRP and NRP-A7) in the context of H-2Kd class I molecules of the major histocompatibility complex (MHC). As pre-diabetic NOD mice age, their islet-associated CD8+ T lymphocytes contain increasing numbers of NRP-A7-reactive cells, and these cells bind NRP-A7/H-2Kd tetramers with increased specificity, increased avidity and longer half-lives. Repeated treatment of pre-diabetic NOD mice with soluble NRP-A7 peptide blunts the avidity maturation of the NRP-A7-reactive CD8+ T-cell population by selectively deleting those clonotypes expressing T-cell receptors with the highest affinity and lowest dissociation rates for peptide-MHC binding. This inhibits the local production of T cells that are cytotoxic to beta cells, and halts the progression from severe insulitis to diabetes. We conclude that avidity maturation of pathogenic T-cell populations may be the key event in the progression of benign inflammation to overt disease in autoimmunity.

Ventilatory and metabolic adaptations to walking and cycling in patients with COPD

To test the hypothesis that in chronic obstructive pulmonary disease (COPD) patients the ventilatory and metabolic requirements during cycling and walking exercise are different, paralleling the level of breathlessness, we studied nine patients with moderate to severe, stable COPD. Each subject underwent two exercise protocols: a 1-min incremental cycle ergometer exercise (C) and a "shuttle" walking test (W). Oxygen uptake (VO(2)), CO(2) output (VCO(2)), minute ventilation (VE), and heart rate (HR) were measured with a portable telemetric system. Venous blood lactates were monitored. Measurements of arterial blood gases and pH were obtained in seven patients. Physiological dead space-tidal volume ratio (VD/VT) was computed. At peak exercise, W vs. C VO(2), VE, and HR values were similar, whereas VCO(2) (848 +/- 69 vs. 1,225 +/- 45 ml/min; P < 0. 001) and lactate (1.5 +/- 0.2 vs. 4.1 +/- 0.2 meq/l; P < 0.001) were lower, DeltaVE/DeltaVCO(2) (35.7 +/- 1.7 vs. 25.9 +/- 1.3; P < 0. 001) and DeltaHR/DeltaVO(2) values (51 +/- 3 vs. 40 +/- 4; P < 0.05) were significantly higher. Analyses of arterial blood gases at peak exercise revealed higher VD/VT and lower arterial partial pressure of oxygen values for W compared with C. In COPD, reduced walking capacity is associated with an excessively high ventilatory demand. Decreased pulmonary gas exchange efficiency and arterial hypoxemia are likely to be responsible for the observed findings.

Reliability of results of the Rose Bengal test performed for export control in northern Somalia

Sera from sheep and goats in northern Somalia which are exported to countries of the Persian Gulf are systematically checked for brucellosis by local veterinary teams. The standard test used is rapid seroagglutination using the Rose Bengal test (RBT) and seropositive animals are not exported. In order to assess the reliability of the serological results, three randomised batches of samples (653 sera), corresponding to an equivalent number of shipments (October and December 1994 and March 1995) were counterchecked. Control RBTs were carried out by expatriate veterinarians working on behalf of international non-governmental organisations and by the Istituto Zooprofilattico Sperimentale of Padua, Italy, which also performed the complement fixation test (CFT). A fourth batch (n = 100), including a group of sera found positive by the local veterinary teams, was also checked. Agreement ranged from 96.3% to 98.5%.

Pulmonary gas exchange and exercise capacity in patients with systemic lupus erythematosus

OBJECTIVE

Exercise tolerance is often reduced in patients with systemic lupus erythematosus (SLE). Mechanisms have been proposed but the underlying causes have not yet been elucidated. The study of pulmonary gas exchange during exercise may be helpful in revealing circulatory, ventilatory, and metabolic abnormalities. We hypothesized that in SLE, exercise aerobic capacity would be reduced due to chronic inactivity and poor muscle energetics.

METHODS

Thirteen women with SLE and low disease activity were studied; 5 age matched subjects served as controls. Clinical examination, chest radiography, electrocardiogram, and pulmonary function test were all normal. Subjects underwent 1 min incremental cycle ergometer exercise to exhaustion. Oxygen uptake (VO2), CO2 output (VCO2), minute ventilation (VE), heart rate (HR), and arterial O2 saturation were monitored. Anaerobic threshold (AT), VO2/HR, deltaVO2/deltaWatt, respiratory rate (RR), Ti/Ttot, VE/VCO2, and breathing reserve (BR) were computed.

RESULTS

At rest, patients exhibited high VE, respiratory alkalosis, and a wide alveolar-arterial O2 gradient [(A - a)O2] during 50% O2 breathing. Other indexes of respiratory function were within the normal range. In the 6 patients with SLE where pulmonary artery systolic pressure at Doppler echocardiography was measurable, mean level was in the upper limits of normal. During exercise, maximal aerobic capacity was reduced in all patients (VO2 peak, 1098+/-74 vs. 2150+/-160 ml/min, p<0.01; AT, 36 +/-3 vs. 48+/-3% predicted VO2 max, p<0.05). Ventilation adjusted for the metabolic demand (VE/VCO2 at AT) was increased (31+/-1 vs. 24+/-1; p<0.05). A normal breathing pattern was observed during all tests. No patient stopped exercising because of ventilatory limitation (i.e., they had normal breathing reserve).

CONCLUSION

Reduced muscle aerobic capacity is common in SLE and is most likely because of peripheral muscle deconditioning. Increased ventilatory demand, secondary to diffuse interstitial lung disease, is not a significant contributor to the reduction in exercise tolerance.

A novel nonsense mutation at Glu-631 in a Spanish family with complement component 7 deficiency

Deficiency of the seventh component of complement (C7D) is frequently associated with recurrent neisserial infections. We report in the present study the genetic basis for C7D in a Spanish family. We used exon-specific polymerase chain reaction (PCR)/single-strand conformation polymorphism (SSCP) analysis as a screening step for mutations, followed by direct sequencing of the target exon. The mutation in the proband was a homozygous G-to-T transversion at nucleotide 1957, the first nucleotide of the codon GAG for Glu-631, leading to a stop codon TAG (E631X). Our result provides further evidence that the molecular pathogenesis of C7D is heterogeneous.