Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC

Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28}  cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25}  cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.

Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.

A Web-Based Physical Activity Portal for Individuals Living With a Spinal Cord Injury: Qualitative Study

Background

The population with a spinal cord injury (SCI) largely remains inactive following discharge from rehabilitation despite evidence on the benefits of physical activity. These individuals need to develop skills to self-manage their condition in order to prevent secondary comorbidities and rehospitalization. A Web-based physical activity portal can address this need. Few Web-based interventions incorporate theoretical frameworks, behavior change techniques, and modes of delivery into their design.

Objective

This study aimed to identify the preferred features of a Web-based self-management physical activity portal through stakeholder engagement with individuals with a spinal cord injury and health care professionals (HCPs).

Methods

An interpretative phenomenology methodology and participatory design, along with an integrated knowledge translation approach, were used to conduct this study. Convenience sampling was used to recruit individuals with an SCI living in the community, who were either interested or already engaging in physical activity, and HCPs working with individuals with an SCI, from three city-based rehabilitation sites. Individual 1-hour sessions involving navigation of an existing website and a semistructured interview were conducted with all participants. Individuals with an SCI completed a demographics questionnaire prior to the individual sessions, while demographic information of the HCPs was collected during their interviews. Additionally, all participants were asked a question on their intention to use or recommend a portal. An in-depth thematic analysis was used to derive themes from participants’ responses.

Results

Thirteen individuals with an SCI and nine HCPs participated in the study. Five core themes emerged: (1) knowledge: guidance and barrier management; (2) possibility of achievement: the risks and benefits of physical activity and modelling; (3) self-regulation strategies: action planning, goal setting, tracking, rewards, and reminders; (4) interactivity: peers and professionals; and (5) format: appearance, language, and ease of use. The mean (median) ratings of the likelihood of promoting and using a Web-based portal tailored to individuals’ needs were 9.00 (8.78) and 7.75 (7.88) for HCPs and individuals with an SCI, respectively.

Conclusions

This study highlights features of an online self-management platform that can provide individuals with an SCI the motivation and volition to engage in physical activity. These findings will inform the design of a Web-based self-management physical activity portal to increase physical activity adherence and behavior change.

Carotid Intima-Media Thickness and Anti-Phospholipid Antibodies in Patients with Systemic Lupus Erythematosus

An increase in mortality due to accelerated atherosclerosis has been reported in patients affected with Systemic Lupus Erythematosus (SLE). Anti-phospholipid antibodies (aPA) may play a pathogenetic role in the development of atherosclerosis. We measured carotid intima-media thickness (IMT), as a surrogate parameter of atherosclerosis, by B-mode ultrasound examination in 42 patients affected with SLE (11 men and 31 women) and in 42 healthy age- and sex-matched subjects. Lupus Anticoagulant (LA) (APTT sensitive, silica clotting time, DRVVT), Anti-cardiolipin antibodies (ACA) IgG and IgM, anti-β2glycoprotein 1 (anti-β2GP1) IgG and IgM and anti-prothrombin (anti-PT) IgG and IgM in ELISA (Orgentec Bouty) were also detected. IMT was 0.538±0.128 mm (0.310–0.866 mm) in SLE vs 0.473±0.084 mm in healthy subjects (-p 0.003–). IMT correlated with patients’ age (p<0.005) and with C Reactive Protein (CRP) (p<0.005), but not with years of disease, hypertension, number of anti-hypertensive drugs, total cholesterol, serum creatinine and proteinuria. Sixteen patients (38%) had aPL: 12 LA, 6 ACA IgG, 4 ACA IgM, 4 anti-β2GP1 IgG, 3 anti-β2GP1 IgM, 2 anti-PT IgG and 1 anti-PT IgM. IMT was not statistically correlated with aPA. Positive and negative aPA patients only differed as regards glomerular filtration rate (76 ml/min vs 113 ml/min - p<0.01–). Frequency of aPA positivity was 50% in Patients with IMT >0.600 mm and 33.3% in those with IMT <0.600 mm. If LA positivity was considered separately, it was 41.6% in patients with IMT >0.600 mm and 23.3% in patients with IMT <0.600 mm. Among the 5 patients with IMT >0.7 mm, 2 had LA positivity (40%) vs 10/37 (27%) of those with minor carotid thickness. In conclusion, IMT, a surrogate parameter of atherosclerosis, was correlated with Patients’ age and CRP and not with presence of aPA, even though, in the group of patients with greater IMT, there was a non-significant higher proportion of positivity for anti-phospholipid antibodies, in particular for Lupus Anticoagulant.

Limits on light-speed anisotropies from Compton scattering of high-energy electrons

The possibility of anisotropies in the speed of light relative to the limiting speed of electrons is considered. The absence of sidereal variations in the energy of Compton-edge photons at the European Synchrotron Radiation Facility's GRAAL facility constrains such anisotropies representing the first nonthreshold collision-kinematics study of Lorentz violation. When interpreted within the minimal standard-model extension, this result yields the two-sided limit of 1.6×10(-14) at 95% confidence level on a combination of the parity-violating photon and electron coefficients (κ(o+))(YZ), (κ(o+))(ZX), c(TX), and c(TY). This new constraint provides an improvement over previous bounds by 1 order of magnitude.

[Ventilatory care]

Mechanical ventilation is considered a supportive, nontherapeutic technology used to perform the work of breathing for patients who are unable to do so on their own. In neonatology, mechanical ventilation is often used for premature neonates who are unable to sustain ventilation because of reduced functional residual capacity due to surfactant deficiency. Mechanical ventilation is thus an attempt to mimic the respiratory system's physiological function of gas exchange until the respiratory system reaches maturation. In pediatrics, mechanical ventilation is rarely used for acute respiratory distress syndrome as shown by Dahlem et al. in 2003 who found that only 9.9% of cases of respiratory failure in PICU was caused by ARDS. For this reason, ventilatory techniques in PICU are very heterogenous from the assisted to the most aggressive controlled modes associated with ventilator maneuvers. There are no specific guidelines for the use of mechanical ventilation in children and the low number of infants with ARDS in PICU makes it difficult to run randomized controlled trials in this population. Thus the algorithms are based on the results of either adult or neonatal studies. The advantage of extrapolating data from the neonatal evidence relates mainly to the prevention of ventilator induced lung injury (e.g., CPAP, HFOV, NIV, permissive hypercapnia, surfattant), of which neonatologists are particularly expert.

Neurofibroma in a striped mullet: histochemical and immunohistochemical study

A case of neurofibroma is reported in a wild striped mullet Mugil cephalus. Macro- and microscopic features are described. The tumor arose on the head as a white-grayish, firm mass protruding outwards but covered by the epidermis. The neoplastic tissue showed well-defined borders and was encapsulated; it was predominantly composed of elongated cells with ellipsoid, hyperchromatic nuclei and pale cytoplasm. The cells were irregularly arranged; in the context of the neoplastic proliferation, these cells were usually densely packed, sometimes forming parallel arrays, but without distinctive nuclear palisades. The diagnosis of neurofibroma is also supported by the positive immunostaining for S-100 and vimentin as well as by the negative calretinin reaction.

[Metabolomics and medical practice]

High resolution NMR spectroscopy, currently known as "metabolomics", is a technology enabling the rapid, noninvasive and low cost determination of low molecular weigh metabolites (e.g. aminoacids) in biological fluids such as plasma, urine, saliva, cerebrospinal fluid and others. According to Nicholson "Metabolomics is the quantitative measurement of the dynamic multiparametric metabolic response of living systems to pathophysiological stimuli or genetic modification". Over the past 10 years this technology made it possible to discover of a number of lesser-known organ-specific metabolites that has been demonstrated to be reliable indicators of both organ function and viability. Consequently metabolomics has been used, with interesting results, for the functional evaluation of many organs (kidney, liver, heart), drug toxicity and post-transplant monitoring. The international literature demonstrates a growing interest for this technology and its capabilities.

Activity of D-carnitine and its derivatives on Trypanosoma infections in rats and mice

Little progress has been made in the treatment of African trypanosomiasis over the past decades. L-carnitine has a major role in glycolysis-based energy supply of blood trypanosomes for it stimulates constant ATP production. To investigate whether administration of the isomer D-carnitine could exert a competitive inhibition on the metabolic pathway of the L-form, possibly resulting in parasite replication inhibition, several formulations of this compound were tested on Trypanosoma lewisi and T. brucei rhodesiense in rodent models. High oral dosages of D-cornitine inner salt and proprionyl-D-carnitine were not toxic to animals and induced about 50% parasite growth inhibition in reversible, i.e. competitive, fashion. A putative mechanism could be an interference in pyruvate kinase activity and hence ATP production. Considering both, lack of toxicity and inhibitory activity, D-carnitine may have a role in the treatment of African trypanosomiasis, in association with available trypanocidal drugs.

Antimicrobial investigation of semipurified fractions of Ginkgo biloba leaves

A total methanolic extract of Ginkgo biloba leaves was fractionated by solvent partition using ethyl acetate (fraction A), n-butanol (fraction B) and water (fraction C). The antimicrobial activity of the three fractions was evaluated using a number of Gram-positive and -negative bacteria and yeasts. The apolar fraction A appeared to be the most interesting because of its activity against several microorganisms; this fraction was further separated by high performance liquid chromatography, and shown to contain substances with strong inhibitory activity against Enterococcus faecalis 31, different from the major known chemical components of G. biloba leaves.

Correlation between a psychometric test and biochemical indices of hepatic encephalopathy in alcoholics

BACKGROUND/AIMS

In alcohol abusers an alteration of responses to psychometric tests has been reported, even when clinical symptoms of hepatic encephalopathy (HE) are absent. Our research was intended to individualize a simple psychometric test, easy enough to be performed also at the patient's home, able to reveal an impending encephalopathy and, consequently, to facilitate earlier treatment.

METHODOLOGY

Twenty-six consecutive male alcoholics were engaged and, after informed consent, the following schedule was applied: administration of a psychometric test, followed by a drawing of blood for the determination of many blood parameters. After 15 days of treatment to detoxicate patients, psychometric tests and blood examinations were repeated.

RESULTS

The results confirmed that common blood examinations are not useful to monitor brain damage in chronic alcoholism, that a psychometric test is able to demonstrate a therapeutic improvement and that a positive and significant correlation has been observed between BBCA/AAA ratio and WAIS Score.

CONCLUSIONS

These preliminary results suggest that it is possible to suspect dangerous biochemical changes by means of a simple psychometric test.

[Clinical and metabolic features of renal calculi in adults in regard to age of onset]

BACKGROUND

In this paper, the clinical and metabolic patterns of nephrolithiasis in different ages of adulthood are studied.

METHODS

Eight-hundred patients observed at the Mauriziano Hospital between 1990 and 1995, were classified into 3 groups, on the basis of age at the onset of disease: A: 20 through 39 years; B: 40 through 59; C: 60 years and over.

RESULTS

Calcium-oxalate stones had a lower recurrence in C (19.1%) and B (31.5%) than in A (41.7%). Pure uric acid stones recurred in 18.9% of C, 16.7% of B and 4.3% of A. The prevalence of hypercalciuria was higher in A (50.3%) than in B (35.9%) and C (36%); so did hypocitraturia. Hyperuricuria was lower in A (5%, p < 0.05) than in B (9.4%) and C (10%). Low urine pH (< 5.5) was 13% in A, 21.3% in B, 38% in C. Prevalence of hyperoxaluria was about 14% in all groups. The whole prevalence of secondary forms of stone disease was 13% in A, 12% in B and 30% in C. Differences among groups were mainly due to prevalence of urological abnormalities and urinary tract infection. In patients without metabolic disturbances. urological abnormalities or urinary tract infections altogether, were 4.6% in A; 5.2% in B; 33% in C. Urological approach removed 8% of stones in A, 5.6% in B and 10.2% in C.

CONCLUSIONS

Higher morbidity in younger patients could be due to a lower prevalence of easier-passing uric acid stones. The higher occurrence of urological disturbances and struvite stones in the elderly could explain the higher morbidity in this group.

Minimal change nephropathy presenting in a patient with primary sclerosing cholangitis

The association of primary sclerosing cholangitis and renal disease is not frequent, and is limited to a few reported cases of immune complex glomerulonephritis. We report the case of a 34-year-old patient with sclerosing cholangitis diagnosed 5 years earlier, with well preserved liver function and no clinical manifestations of cholestasis, who developed minimal change nephropathy. During the nephrotic phase of the disease, the peripheral blood lymphocyte count was normal, with a relative increase in percent CD4+ and an increase in the CD4+: CD8+ ratio. CD4+ cells showed immunoactivation. The HLA-DR expression on T-cells was 59%, and 16.5% of CD3+ cells were CD25+. A course of prednisone therapy induced long-lasting remission of the nephrotic syndrome. Peripheral blood lymphocyte count and subtyping were normal 7 months after prednisone withdrawal. We conclude that primary sclerosing cholangitis can be associated with minimal change nephropathy; underlying cell-mediated immunity may be the common pathogenic mechanism.

Incidence of biopsy-proven primary glomerulonephritis in an Italian province

Between January 1, 1970, and December 31, 1994, 1,926 cases of biopsy-proven primary glomerulonephritis (PGN) were diagnosed in an adult population (> 15 years of age) in a northwestern region of Italy with approximately 3.5 million inhabitants. The principal long-term changes were an increase in the absolute number of biopsies per year, an increase in the mean age of patients undergoing biopsy (from 29.3 +/- 12.2 years to 47.0 +/- 17.8 years), an increase in the percentage of patients older than 65 years (from 1.7% to 20.4%), and an increase in the percentage of isolated urinary abnormalities as an indication for biopsy (from 3.5% to 29.6%). In the total biopsy material, immunoglobulin A glomerulonephritis (IgA-GN) is the most frequent type (26%), followed by membranous glomerulonephritis (MGN; 20%). An incidence study was begun in 1990; this survey was restricted to the population of the province of Torino (approximately 2 million inhabitants) as only this area completely refers to the nephrologic centers that entered patients into this study. The overall incidence of PGN is 4.68 new cases/yr/10(5) population with a predominance of males (> 2:1); IgA-GN is the most common type (1.47/yr/10(5) population [34.5%]) in the overall population. In the elderly, cases of PGN are twice as high as in adults (8.19/yr/10(5) population v 4.02/yr/10(5) population in the 65 to 74 year and 45 to 54 year age groups, respectively); MGN mainly accounts for this high incidence (3.4/yr/10(5) population), while the nephrotic syndrome is the most common indication for biopsy (53.8%). A comparison with the incidence in the same area in the early 1970s is evaluable only for PGN, which was mainly registered in the age groups for which an unrestricted biopsy policy was already in place (15 to 35 years). In contrast with a misleading increase of all types of PGN, which is in reality due to the extension of the biopsy policy to older and asymptomatic patients, membranoproliferative glomerulonephritis type I shows a countercurrent decrease from 0.43 to 0.13/yr/10(5) population. Evidence of a simultaneous decrease in severe cardiac valvulopathy, due to rheumatic fever, is also provided. We feel that before epidemiologic conclusions can be reached, a clear understanding of one's own biopsy policy is essential. An apparent change in the PGN rate in our region over the last 25 years mainly depends on modifications in our biopsy policy, most probably coupled with a change in the threshold of detection of symptoms in the general population. At present, according to our experience, IgA-GN is the most common type of PGN in the total bioptic material, as demonstrated in other European countries, while the elderly show a peculiar pattern with a higher PGN incidence, mainly represented by MGN and heralded by the nephrotic syndrome. We also confirm that membranoproliferative glomerulonephritis type I is indeed decreasing in parallel with changes in the microbiologic environment.

[Wegener's granulomatosis. Diagnosis and follow-up of 7 cases]

Wegener's granulomatosis (WG) is a rare small vessels necrotizing and granulomatous systemic vasculitis which usually affects the respiratory-tract and the kidneys. Diagnosis is often difficult, but has become easier with antineutrophil cytoplasmic antibodies (ANCA) detection that may justify a more aggressive biopsy policy also in the elderly. Classic treatment with steroids and oral cyclophosphamide (CY) has proven to be of benefit, but side-effects are severe and frequent and the search for less toxic therapeutic schemes should be encouraged. We treated with intravenous pulses of CY (1 g/m2 monthly for 6 months, every two months for the following 6 and quarterly for another year) 5 of 7 patients with WG recently admitted to our institution. We obtained a quick, complete response in 4 of these patients, with no side effects, nor relapses, after a mean follow-up of 17 months. The only patient who did not respond was identified soon after the beginning of the treatment because of a poor reduction of ESR and could be shifted to oral administration of CY successfully. From our still limited experience CY intravenous pulses have proven to be safe and effective enough to advice its use as the first-choice treatment for WG.

[Bartter's syndrome in children and adults. Study of 6 cases]

Six patients (3 children and 3 adults) with the clinical and biochemical features of Bartter's syndrome are presented. Pediatric cases included a more severe form, in one patient, with physical and mental retardation, hypercalciuria and nephrocalcinosis, and a less severe one, including two patients, with milder clinical features, low calcium and high magnesium excretion and hypomagnesiemia. Adult patients were affected by either the mild congenital form (case n. 4) or the acquired variety (cases n.5 and 6). Tubular function was investigated in the 3 adults by assessing clearance measurements during maximal diuresis. There was a defective fractional distal solute reabsorption (FDR) ranging between 0.52 and 0.60. This was well below the results obtained in one patient with psychogenous vomiting (FDR 0.94) and comparable to those in two patients with interstitial nephropathies caused by vesico-ureteral reflux (FDR 0.63 and 0.67 respectively). We concluded that: 1) the etiopathogenetic spectrum of Bartter's syndrome corresponds to different clinical presentation (mild, heavy, congenital or acquired varieties), and alterations in mineral and electrolyte renal handling; 2) reduction in FDR is a feature neither essential nor exclusive of this syndrome.

Activity of terbinafine against Pneumocystis carinii in vitro and its efficacy in the treatment of experimental pneumonia

The antiprotozoan and antifungal agent, the terbinafine, was investigated for its potential activity against Pneumocystis carinii infection of the A549 cell line culture and on immunosuppressed Sprague Dawley rats in comparison with trimethoprim-sulphamethoxazole and pentamidine isethionate. Terbinafine suppressed P. carinii growth at doses up to 3 g/L within 24 h and it was able to inhibit cyst forms at 60 h post inoculation. With respect to trimethoprim-sulphamethoxazole and pentamidine isethionate P. carinii organisms decreased at the same time interval but cyst form elimination was less apparent than with terbinafine. The results of the in-vitro culture were consistent with the in-vivo observations. Of the 3 groups of rats tested, the occurrence of P. carinii pneumonia was documented in 18 (60%) of the control rats (group 3) which showed a high degree of P. carinii burden and a marked weight loss with respect to the beginning of the experiment. Among terbinafine treated rats (group 1), P. carinii pneumonia was present in one rat (3.3%), while no P. carinii infection occurred in the pentamidine isethionate and in trimethoprim-sulphamethoxazole treatment rat groups (group 2). All the agents investigated showed no particular signs of toxicity. These preliminary results suggest further explorations of the terbinafine in clinical trials for treatment and prophylaxis of P. carinii pneumonia.

[Renal damage in rheumatoid arthritis]

Renal damage is not uncommon in rheumatoid arthritis, but the causative role of the disease per se is not well defined yet. In this paper the updated literature data are reported and our own experience as well. In particular, we describe renal syndromes associated with non-steroidal antiinflammatory drugs, remission-inducing agents (gold and penicillamine) and cytotoxic drugs, secondary amyloidosis, systemic rheumatoid vasculitis, glomerular and tubulo-interstitial nephritis not related to drug therapy.

Oral immunization: turning fantasy into reality

The application of oral immunization as the primary means to deliver multivalent vaccines to large populations has many theoretical advantages. However, widespread success in achieving protective immunity against these diseases through oral immunization requires additional understanding of the basic mechanisms of host resistance in the mucosal tissues. Fundamental issues, such as the lineage and repertoire or regulatory pathway of mucosal effector cells, are only now just beginning to be understood. A more comprehensive understanding of these issues could greatly enhance our success at designing and applying successful oral immunization programs.

Isolate antibody to hepatitis C virus core antigen (C22) by RIBA-2: correlation with HCV-RNA and anti-NS5

The presence of circulating hepatitis C virus genome (HCV-RNA), elevated ALT levels and antibodies to an NS5-derived synthetic peptide have been examined in 13 subjects with isolate positivity for antibodies to the HCV core antigen (C22) on RIBA-2 testing. All subjects were followed up for 8-18 months (mean 12.4 months). In seven subjects (54%), intermittent or persistent viremia was associated with abnormal ALT levels (6 subjects) and with positivity for antibodies to NS5-peptide (6 subjects). On the other hand, in 6 out of 13 subjects (46%) no viral replication, no liver cytonecrosis and no antibodies to NS5 were found. It is concluded that isolate reactivity to C22 by RIBA-2 is a heterogeneous condition that corresponds to two distinct categories of subjects: those with active HCV infection and those without evidence of virus replication. Although HCV-RNA determination is the most reliable means of identifying HCV carriers, antibodies to NS5 can be a useful marker of virus activity. In fact, antibodies to NS5 were detected in 6 out of 7 viremic patients, compared to 0 out of 6 non-viremic patients (P = 0.004). It remains to be elucidated whether the isolate reactivity to core antigen found in non-viremic subjects represents a specific, HCV-induced antibody response, or is an unrelated crossreactivity.

Acute hepatitis in childhood: virological, immunological and clinical aspects

Virological, immunological and clinical findings in 7 previously healthy children, aged 18 months to 11 years, with viral hepatitis are reported. Asymptomatic and fully recovering, although protracted, hepatitis B was diagnosed by chance in a 1 1/2 year-old boy. Anicteric and short-term hepatitis occurred in three children with Epstein-Barr virus infection, concomitantly with typical mononucleosis syndrome. On the contrary, cytomegalovirus (CMV)-associated hepatitis was severe and protracted in two children, and fatal in a 4-year-old girl, whose main autoptic finding was submassive hepatic necrosis. Therefore, our study showed that acute viral hepatitis in non-immunocompromised children is generally self-limited and that CMV hepatitis is more frequent and severe than commonly believed.

One course versus two courses of recombinant alpha interferon in chronic C hepatitis

Fifty-five patients with antibodies to HCV and chronic liver disease have been enrolled in the study. Thirty-four patients were treated with recombinant alpha interferon (IFN, 3 MU daily for 10 days followed by 3 MU twice/week for 3 months), and were compared to 21 untreated controls. Alanine aminotransferase (ALT) normalization was observed in a significant proportion of treated patients (52.9%), but 66.6% of them experienced a relapse after discontinuation of the therapy. The evaluation of the early ALT behavior after the 10 days priming with daily IFN administration was useful in predicting the response. The administration of a second IFN course with the same schedule and duration as the first course did not increase the efficacy of the treatment. Increased dosage and/or prolonged administration are probably required.

Renal handling of citrate in chronic renal insufficiency

Citrate is a relevant component of the inhibitory potential of the urine environment. Its excretion and renal handling have been widely studied in subjects with normal renal function, but little is known about changes induced by chronic renal insufficiency. We have investigated renal handling of citrate in 50 patients with different degrees of renal insufficiency as compared to 30 healthy subjects with normal renal function. Among patients 34 were defined as having mild renal insufficiency based on a GFR of 80 through 40 ml/min/1.73 m2 BSA, while 16 had moderate-to-severe renal failure, defined by a GFR ranging from 40 to 20 ml/min/1.73 m2 BSA. Serum citrate increased in mild renal insufficiency, while it tended to be restored to normal values at more advanced renal failure. There was a stepwise decrease in the filtered load of citrate as GFR decreased, while its renal clearance was significantly reduced only at higher degrees of renal failure. This behavior was due to an increase in the fractional excretion of citrate which was inversely related to the decrease in GFR (p = 0.015). These data suggest that serum citrate levels and excretion are governed by renal mechanisms at mild degrees of renal insufficiency; in these conditions citrate is shown to behave conformly to other poorly reabsorbable anions such as sulfate. At more advanced renal failure the ensuing metabolic acidosis plays a crucial role as a regulatory factor of both serum concentration and renal handling of citrate, by increasing cellular uptake and metabolism as well as tubular reabsorption of this anion.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of chronic renal insufficiency in the course of idiopathic recurrent calcium stone disease: risk factors and patterns of progression

The occurrence of chronic renal insufficiency was investigated in 171 patients with severe idiopathic calcium stone disease. Ninety healthy subjects matched for age and sex were used as controls. The patients were thereafter subclassified into two subgroups, assuming a GFR of 80 ml/min/1.73 m2 body surface area as a cut-off value: the normal GFR, 141 patients, and the impaired GFR, 30 patients. The normal GFR group included more males and the patients were younger both at onset and at presentation. In the impaired GFR group the disease lasted longer, but the overall stones and the stone recurrence rate were as high as those of the normal GFR patients. The single stone episodes were more severe in the former group as suggested by the occurrence of more surgery and complications. The GFR level was in part predicted by the age of patients; however, stone disease was shown to induce a clear-cut influence in accelerating the natural worsening of GFR with age. The onset of renal insufficiency causes multiple changes in renal pathophysiology, which result in a sharp decrease in the urine saturation with respect to calcium salts. These changes account for the decrease in the stone recurrence rate in the impaired GFR group. Thus, unless factors independent of or complicating the calcium stone disease supervene, the renal insufficiency of treated patients remains mild and relently progressive.

Comparative analysis of immunological responses to oral (Ty21a) and parenteral (TAB) typhoid vaccines

The clinical and immunological responses to typhoid vaccination with parenteral (TAB) and oral (Ty21a) vaccines in two groups of 30 adult male subjects were studied. Parameters monitored included specific anti-Salmonella typhi cell-mediated immunity and total and specific antilipopolysaccharide fecal immunoglobulin A (IgA) titers in Ty21a-vaccinated subjects. Peripheral blood lymphocytes antibacterial activity was significantly increased only in Ty21a-vaccinated subjects. Serum arming activity and results of human F(ab')2 anti-IgG and -IgA inhibition tests suggest antibody-dependent cellular cytotoxicity mediated by IgA in those vaccinated with Ty21a. Interestingly enough, the cells of TAB-vaccinated subjects were able to mediate IgG-dependent cellular cytotoxicity, as was observable from the results of blocking experiments. Moreover, total and specific antilipopolysaccharide fecal IgA levels were observed to be significantly increased with Ty21a, up to 8 months post-vaccination schedule. An early-onset, transitory increase in serum IgM rheumatoid factor was also found, exclusively in subjects treated with TAB, and was no longer detectable on day 240. Ty21a was well tolerated and free of side effects, whereas 65% of subjects administered TAB reported fever, headache, malaise, and local tenderness at the injection site. Our data show that the two typhoid vaccines induce different cell-mediated specific immune responses. The role of these responses in protection against Salmonella infection, however, requires further investigation.