BepiColombo mission confirms stagnation region of Venus and reveals its large extent

The second Venus flyby of the BepiColombo mission offer a unique opportunity to make a complete tour of one of the few gas-dynamics dominated interaction regions between the supersonic solar wind and a Solar System object. The spacecraft pass through the full Venusian magnetosheath following the plasma streamlines, and cross the subsolar stagnation region during very stable solar wind conditions as observed upstream by the neighboring Solar Orbiter mission. These rare multipoint synergistic observations and stable conditions experimentally confirm what was previously predicted for the barely-explored stagnation region close to solar minimum. Here, we show that this region has a large extend, up to an altitude of 1900 km, and the estimated low energy transfer near the subsolar point confirm that the atmosphere of Venus, despite being non-magnetized and less conductive due to lower ultraviolet flux at solar minimum, is capable of withstanding the solar wind under low dynamic pressure.

Inner southern magnetosphere observation of Mercury via SERENA ion sensors in BepiColombo mission

Mercury's southern inner magnetosphere is an unexplored region as it was not observed by earlier space missions. In October 2021, BepiColombo mission has passed through this region during its first Mercury flyby. Here, we describe the observations of SERENA ion sensors nearby and inside Mercury's magnetosphere. An intermittent high-energy signal, possibly due to an interplanetary magnetic flux rope, has been observed downstream Mercury, together with low energy solar wind. Low energy ions, possibly due to satellite outgassing, were detected outside the magnetosphere. The dayside magnetopause and bow-shock crossing were much closer to the planet than expected, signature of a highly eroded magnetosphere. Different ion populations have been observed inside the magnetosphere, like low latitude boundary layer at magnetopause inbound and partial ring current at dawn close to the planet. These observations are important for understanding the weak magnetosphere behavior so close to the Sun, revealing details never reached before.

SERENA: Particle Instrument Suite for Determining the Sun-Mercury Interaction from BepiColombo

The ESA-JAXA BepiColombo mission to Mercury will provide simultaneous measurements from two spacecraft, offering an unprecedented opportunity to investigate magnetospheric and exospheric particle dynamics at Mercury as well as their interactions with solar wind, solar radiation, and interplanetary dust. The particle instrument suite SERENA (Search for Exospheric Refilling and Emitted Natural Abundances) is flying in space on-board the BepiColombo Mercury Planetary Orbiter (MPO) and is the only instrument for ion and neutral particle detection aboard the MPO. It comprises four independent sensors: ELENA for neutral particle flow detection, Strofio for neutral gas detection, PICAM for planetary ions observations, and MIPA, mostly for solar wind ion measurements. SERENA is managed by a System Control Unit located inside the ELENA box. In the present paper the scientific goals of this suite are described, and then the four units are detailed, as well as their major features and calibration results. Finally, the SERENA operational activities are shown during the orbital path around Mercury, with also some reference to the activities planned during the long cruise phase.

Diagnosis of suspected inherited platelet function disorders: results of a worldwide survey

BACKGROUND

Diagnosis of inherited platelet function disorders (IPFDs) is important for appropriate management and to improve epidemiologic and clinical knowledge. However, there remains a lack of consensus on the diagnostic approach.

OBJECTIVES

To gain knowledge on the current practices for the diagnosis of IPFD worldwide.

METHODS

A 67-item questionnaire was distributed to the ISTH members and to the members of several national hemostasis and thrombosis societies.

RESULTS

A total of 202 laboratories from 37 countries participated in the survey. The most frequent criterion to define patients with a suspected IPFD was a history of mucocutaneous bleeding and no acquired cause, but heterogeneity on the identification criteria was evident. Only 64.5% of respondents performed a direct clinical interview. On average, each laboratory studied 72 patients per year. The most commonly used laboratory equipment were the light-transmission aggregometer, the Platelet Function Analyzer-100, and the flow cytometer. Screening tests were platelet count, peripheral blood smear, light-transmission aggregometry, and Platelet Function Analyzer-100. Second-step tests were flow cytometry, molecular genetic analysis, and electron microscopy. Methodologies varied widely. In total, ~ 14,000 patients were investigated yearly and 60% turned out to not have a defect. Of the remaining 40%, only 8.7% received a diagnosis at a molecular level.

CONCLUSIONS

Many laboratories worldwide are involved in the diagnosis of IPFD. A large fraction of the patients studied remain without a diagnosis. A high variability in the diagnostic approaches is evident.

Elbow rehabilitation in traumatic pathology

The elbow, intermediate joint of the upper limb, frequently undergoes to pathological events and is especially prone to stiffness. Rehabilitation plays an important role in recovering functional activities. For the rehabilitation team, this goal always represents a challenge, as the treatment has to be continuously modeled and calibrated on the needs of the individual patient, even many times during the same rehabilitation cycle. Containing the effects of immobilization, avoiding to excessively stress the healing tissues, satisfying specific clinical criteria before moving to the next rehabilitation stage, basing the rehabilitation plan on up-to-date clinical and scientific data that can be adapted to each patient and to his/her needs are the basic principles of the rehabilitation plan, which can be chronologically grouped into four rehabilitation stages. After summarizing the general principles of elbow treatment, the specific principles of rehabilitation after elbow fractures and elbow instability are presented, and then the rehabilitative approach to the most frequent and feared pathological conditions of the elbow, namely stiffness, is described.

Risk management in surgery

Malpractice is the responsible for the greatest number of legal claims. At the present time, legal actions against physicians in Italy are 15,000 per year, and a stunning increase about costs to refund patients injured by therapeutic and diagnostic errors is expected. The method for the medical prevention is "Risk Management", that is the setting-up of organizational instruments, methods and actions that enable the measurement or estimation of medical risk; it allows to develop strategies to govern and reduce medical error. In the present work, the reconstruction about the history of risk management in Italy was carried out. After then the latest initiatives undertaken by Italy about the issue of risk management were examined.

Single-incision laparoscopic appendectomy is comparable to conventional laparoscopic and laparotomic appendectomy: our single center single surgeon experience

Several studies have demonstrated the clinical and technical benefits of the laparoscopic surgery for complicated and uncomplicated appendicitis. Our retrospective study included 12 patient who underwent SILS appendectomy (SILS-A), 14 who received conventional laparoscopic surgery (VL-A), and 12 who received laparotomic appendectomy (OA); performed in all cases by the same surgeon (C.F.). The aim of this study was the comparison between this three different surgical techniques on same features: post operative leukocytosis, post operative pain, need abdominal drainage, esthetic viewpoint, incidence of complication, hospital stay. The results showed no significant differences between SILS-A and VLS-A, while an evident improvement shows versus O-A, even though not statistically significative. SILS was more effective in decreasing the risk of postoperative wound infection.

The burden of visceral leishmaniasis in Italy from 1982 to 2012: a retrospective analysis of the multi-annual epidemic that occurred from 1989 to 2009

Starting from 1989 Italy experienced an increase of visceral leishmaniasis (VL) cases over a baseline of 10 to 30 cases reported annually. The number of cases peaked in 2000 and 2004 with more than 200 cases/year, and subsequently declined to reach on average one third of the 2000 peak value in the period after 2010. A retrospective analysis from 1982 to 2012 showed that the multi-annual epidemic consisted of major components including (i) an outbreak involving infants and immunocompetent adults in parts of the Campania region (southern peninsular Italy) and that appears to have declined naturally, (ii) a second outbreak affecting human immunodeficiency virus (HIV)-infected individuals throughout the country, that declined owing to the use of highly active antiretroviral therapies (HAART), (iii) a generalised increase of VL cases in immunocompetent individuals and patients affected by associated conditions other than HIV from endemic regions of peninsular and insular Italy (other than Campania), which was due to a geographical spreading of VL foci, with no major case-clusters or outbreak features. A minor component consisted in the appearance of a few autochthonous cases in formerly non-endemic areas, starting from the early 1990s. Epidemic determinants and reasons for VL decline in the Campania region remain largely unexplained, despite the information available on canine reservoir and phlebotomine vectors in Italy.

The burden of visceral leishmaniasis in Italy from 1982 to 2012: a retrospective analysis of the multi-annual epidemic that occurred from 1989 to 2009

Starting from 1989 Italy experienced an increase of visceral leishmaniasis (VL) cases over a baseline of 10 to 30 cases reported annually. The number of cases peaked in 2000 and 2004 with more than 200 cases/year, and subsequently declined to reach on average one third of the 2000 peak value in the period after 2010. A retrospective analysis from 1982 to 2012 showed that the multi-annual epidemic consisted of major components including (i) an outbreak involving infants and immunocompetent adults in parts of the Campania region (southern peninsular Italy) and that appears to have declined naturally, (ii) a second outbreak affecting human immunodeficiency virus (HIV)-infected individuals throughout the country, that declined owing to the use of highly active antiretroviral therapies (HAART), (iii) a generalised increase of VL cases in immunocompetent individuals and patients affected by associated conditions other than HIV from endemic regions of peninsular and insular Italy (other than Campania), which was due to a geographical spreading of VL foci, with no major case-clusters or outbreak features. A minor component consisted in the appearance of a few autochthonous cases in formerly non-endemic areas, starting from the early 1990s. Epidemic determinants and reasons for VL decline in the Campania region remain largely unexplained, despite the information available on canine reservoir and phlebotomine vectors in Italy.

Technique and outcomes about a new laparoscopic procedure: the Pelvic Organ Prolapse Suspension (POPS)

Pelvic organ prolapse suspension (POPS) is a recent surgical procedure for one-stage treatment of multiorgan female pelvic prolapse. This study evaluates the preliminary results of laparoscopic POPS in 54 women with a mean age of 55.2 and a BMI of 28.3. Patients underwent at the same time stapled transanal rectal resection (STARR) to correct the residual rectal prolapse. We had no relapses and the preliminary results were excellent. We evaluated the patients after 1 year follow-up and we confirmed the validity of our treatment. The technique is simpler than traditional treatments with an important reduction or completely disappearance of the pre-operative symptomatology.

Proposal for SICSeG guidelines for rehabilitation after anatomical shoulder prosthesis in concentric shoulder osteoarthritis

PURPOSE

The purpose of this paper is to provide up-to-date guidelines on rehabilitation after anatomical shoulder prosthesis for concentric shoulder osteoarthritis, as previous guidelines date back to late 1970s and are no longer adequate due to the evolution of prosthesis models and surgical techniques.

METHODS

The physiatric committee of the Italian Society of Shoulder and Elbow Surgery (SICSeG-Società Italiana di Chirurgia della Spalla e del Gomito) performed a search for all the existing literature related to rehabilitation after shoulder replacement. A total of 29 papers concerning shoulder rehabilitation were reviewed. In addition, the main Italian orthopedic surgeons and physiatrists dealing with shoulder surgery and rehabilitation were interviewed to obtain indications when literature was not conclusive.

RESULTS

From literature evaluation and expert consultation, we produced guidelines concerning: patient evaluation by means of adequate rating scales, preoperative treatment, early intermediate and advanced postoperative phases, rehabilitation of scapulo-thoracic joint, return to work and sports, length of rehabilitation and follow-up.

CONCLUSIONS

This proposal for guidelines was presented during the 11th SICSeG Congress on May 2012 and to the main scientific societies concerned in shoulder surgery and rehabilitation. A consensus conference is needed in order to formalize and make them usable from all the professional figures involved in this field.

[Patients' satisfaction for hospital care among the Italian Regions between 1997 and 2009]

Patients have a privileged perspective on health care quality, thus it is important to obtain from them judgments about offered services. Currently, there are no well developed quality monitoring systems related to the patient's perspective, though Istat data sources would b helpful on this issues. We performed a descriptive analysis relating to the satisfaction degree of Italian population for hospital admissions between 1997and 2009. Data were taken from the Istat Multipurpose analysis on some aspect of daylife. Our results show a positive appraisal for medical and nursing assistance; however the rating for the quality of food is lower Our analysis would give a contribution to the appraisal of an outstanding dimension of patients' appraisal of quality of care among the Regions, by considering the implementation of devolution in healthcare since 2001.

Solar Wind-Induced Atmospheric Erosion at Mars: First Results from ASPERA-3 on Mars Express

The Analyzer of Space Plasma and Energetic Atoms (ASPERA) on board the Mars Express spacecraft found that solar wind plasma and accelerated ionospheric ions may be observed all the way down to the Mars Express pericenter of 270 kilometers above the dayside planetary surface. This is very deep in the ionosphere, implying direct exposure of the martian topside atmosphere to solar wind plasma forcing. The low-altitude penetration of solar wind plasma and the energization of ionospheric plasma may be due to solar wind irregularities or perturbations, to magnetic anomalies at Mars, or both.

Complications after stapled hemorrhoidectomy: can they be prevented?

Stapled hemorrhoidectomy (SH), a new approach to the treatment of hemorrhoids, removes a circumferential strip of mucosa about four centimeters above the dentate line. A review of 1,107 patients treated with SH from twelve Italian coloproctological centers has revealed a 15% (164/1,107) complication rate. Immediate complications (first week) were: severe pain in 5.0% of all patients, bleeding (4.2%), thrombosis (2.3%), urinary retention (1.5%), anastomotic dehiscence (0.5%), fissure (0.2%), perineal intramural hematoma (0.1%), and submucosal abscess (0.1%). Bleeding was treated surgically in 24%, with Foley insertion 15%; and by epinephrine infiltration in 2%; 53% of patients with bleeding received no treatment and 6% needed transfusion. One patient with anastomotic dehiscence needed pelvic drainage and colostomy formation. The most common complication after 1 week was recurrence of hemorrhoids in 2.3% of patients, severe pain (1.7%), stenosis (0.8%), fissure (0.6%), bleeding (0.5%), skin tag (0.5%), thrombosis (0.4%), papillary hypertrophy (0.3%) fecal urency (0.2%), staples problems (0.2%), gas flatus and fecal incontinence (0.2%), intramural abscess, partial dehiscence, mucosal septum and intussusception (each <0.1%). Recurrent hemorrhoids were treated by ligation in 40% and by Milligan-Morgan procedure in 32%. All hemorrhoidal thromboses were excised. Anal stenoses were treated by dilatation in 55% and by anoplasty in 45%. Fissure was treated by dilatation in 57%. Most complications (65%) occurred after the surgeon had more than 25 case experiences of stapled hemorrhoidectomy. The most common complication in the first 25 cases of the surgeon's experience was bleeding (48%). Even though SH appears to be promising, we feel that a multicenter randomized study with a long-term follow-up comparing SH and banding is necessary before recommending the procedure. Most complications can be avoided by respecting the rectal wall anatomy in the execution of the procedure.

Solar UV radiation: differential effectiveness of UVB subcomponents in causing cell death, micronucleus induction and delayed expression of heritable damage in human hybrid cells

PURPOSE

To determine the effectiveness of two UV spectra with different UVB components for cell kill and micronucleus induction in irradiated human HeLaxskin fibroblast (CGL1) hybrid cells and their progeny. To determine the presence of reactive oxygen species (ROS) in the progeny of the irradiated cells at various post-irradiation times and their relationship with induced delayed biological effects.

MATERIAL AND METHODS

A commercial solar ultraviolet simulator was used. Two different filters were employed: the first transmitted radiation with lambda>284nm and the second radiation with lambda>293nm. The resulting spectra have different UVB components (lambda between 284 and 320nm, 19 W/m(2), and between 293 and 320nm, 13 W/m(2)) and the same UVA component (lambda between 320 and 400nm, 135 W/m(2)). CGL1 cells were irradiated with various doses. Clonogenic survival and micronucleus formation were scored in the irradiated cells and their progeny. ROS were detected by incubation of cultures at various post-irradiation times with dichlorodihydrofluorescein diacetate followed by flow cytometric measurement of the final product, dichlorofluorescein.

RESULTS

The biological effectiveness of the lambda>284nm spectrum was higher by a factor of 3 compared to the lambda>293nm spectrum for cell kill, and by a factor of 5 for micronucleus induction. No delayed cell death or micronucleus formation was found in the progeny of cells exposed to lambda>293nm, while a large and dose-dependent effect was found in the progeny of cells exposed to lambda>284nm for both of these endpoints. ROS levels above those in unirradiated controls were found only in the progeny of cells exposed to the lambda>284nm spectrum.

CONCLUSIONS

The spectrum with lambda>284nm was more effective than that with lambda>293nm for induction of cell kill and micronucleus formation in the directly irradiated cells as well as induction of delayed effects in the progeny in the form of delayed reproductive death and micronucleus formation. The presence of ROS in the progeny of the irradiated cells may be the cause of the delayed effects.

[The general surgeon's experience in emergency gynaecological laparoscopy]

BACKGROUND

Early laparoscopy plays a very important role in the diagnosis and treatment of uncertain surgical diseases. Its use is not very clear, in part because it is a very new technique and secondly because its application in emergency surgery is very recent. The aim of this study is to evaluate the efficacy of this surgical approach.

METHODS

In the last six years, during emergency laparoscopy, we diagnosed various gynaecological diseases. We performed 4 ovarian cystectomies (25%), 2 salpingectomies (12.5%), 6 salpingo-oophorectomies (37.5%), 2 myomectomies (18.75%), 1 endocoagulation (6.25%).

RESULTS

Neither conversion in open surgery, nor major postoperatory complications were noted. Intervention time was shorter than that of the open technique. Return to normal activity was earlier.

CONCLUSIONS

The results of this study contribute to demonstrate that, in emergency surgery, laparoscopy constitute a valid and efficient diagnostic and therapeutic technique. It is indicated for the treatment of acute abdomen of unknown origin.

[Efficacy of somatostatin and its analogues in the treatment of acute pancreatitis: clinical retrospective study]

Acute pancreatitis is an acute inflammatory disease of the pancreas, with variable involvement of other regional tissues or remote organ systems. Acute pancreatitis is mild in 80% of cases; virtually all patients with this form of disease will survive, because it's associated with minimal organ dysfunction and uneventful recovery; the severe pancreatitis develops in 20% of cases and is associated with higher morbidity and mortality. It's most important to identify the severity of disease at the moment of hospital admission; many scoring systems have been developed to serve as early prognostic signs: Ranson's criteria, Imrie's criteria, Apache II score, Balthazar's TC score. Recently, new drugs have been proposed in the treatment of acute pancreatitis, as, for example, calcitonine, glucagon, systemic antioxidants, antagonists of the receptors of interleukines, antiproteases (aprotinin and gabexate-mesilate) and the inhibitors of pancreatic secretions (somatostatin and its analogues). However, many controversies still exist concerning the real efficacy of these drugs in the treatment of acute pancreatitis, particularly regarding the inhibitors of pancreatic secretions: recently, some studies showed that somatostatin is able to actually reduce the local complication of the disease and the development of severe forms of acute pancreatitis; on the other hand, other studies failed to show real advantages of somatostatin reducing morbidity and mortality for pancreatitis. The aim of present study is a retrospective analysis of patients affected by acute pancreatitis in order to evaluate efficacy of somatostatin and its analogues. All patients subdivided in two groups: group A, patients treated with conventional therapy plus somatostatin and/or octreotide (SS/LS), and group B, patients treated only with conventional therapy. Results seem to show that somatostatin does not positively affect morbidity and mortality in patients with acute pancreatitis. The Authors conclude that, at present; somatostatin cannot be considered surely effective in preventing complications and mortality in acute pancreatitis. Further studies are still necessary to verify the effectiveness of somatostatin and its analogues in the therapy of acute pancreatitis.

Comparative efficacy of meglumine antimoniate and aminosidine sulphate, alone or in combination, in canine leishmaniasis

Thirty-two domestic dogs naturally infected with Leishmania infantum and showing viscero-cutaneous signs of canine leishmaniasis were treated with aminosidine sulphate (11 dogs) meglumine antimoniate (10 dogs) or with a combination of the two drugs (11 dogs) for 21 consecutive days. Clinical and laboratory assessments, made on day 21 and at 2, 4 and 6 months after initiation of treatment, showed that the drug combination gave the best score in terms of clinical efficacy, incidences of early clinical relapse, any clinical relapse or apparent parasitological cure, and reduction in parasite densities in bone-marrow and lymphnode aspirates (even though a lower dose of antimonial was used in the combination than for antimonial monotherapy). For each of the above parameters, however, the higher efficacy of the drug combination was not statistically significant, probably because of the large variations caused by using naturally infected animals of various ages and breeds.

Activity of liposomal amphotericin B (AmBisome) in dogs naturally infected with Leishmania infantum

Thirteen dogs naturally infected with Leishmania infantum showing viscero-cutaneous signs of disease were treated with different dosages of liposomal amphotericin B (AmBisome). The animals were followed clinically and parasitologically over a period of eight months. Dogs which received three to five administrations of AmBisome 3-3.3 mg/kg showed rapid clinical improvement, with regression of lymphadenomegaly and splenomegaly, and cure of skin lesions. The clinical response was similar to that obtained with 14-21 doses of conventional antileishmanial drugs. However, follow-up lymph node aspirates remained positive for Leishmania in all dogs except one, which was treated with the total dose of AmBisome 15 mg/kg. The failure in parasitological cure may be due to inadequate drug targeting to parasitized cells, or to T-cell immune depression characteristic of patent cases of canine leishmaniasis, or to both.

[The treatment of arterial hypertension in diabetes mellitus. Choices and problems]

Recent studies indicate that arterial hypertension in diabetes mellitus is a paramount pathogenetic step in the evolution and acceleration of diabetic macro- and microangiopathy and in particular in the development of nephropathy and uremia. This paper deals with the clinical problems of antihypertensive treatment in diabetic patients and discusses the antihypertensive repertory with the aim at determining the best drug choice in the individual case. In the light of our present pathophysiologic knowledges of the intrarenal effects of the various classes of antihypertensive drugs the possibility of preventing diabetic nephropathy is discussed.

Frequency of chromosomal aberrations after exposure to gamma-radiation of human chorionic villi

We investigated the chromosomal damage induced by in vitro exposure to gamma-rays of uncultured first trimester chorionic villi. Frequency and types of chromosomal aberrations at increasing doses of radiation have been evaluated on cytotrophoblast spontaneous metaphases obtained after a short term incubation. Our results indicate a direct correlation between radiation dose and aberration frequency.

Activity of liposomal amphotericin B (AmBisome) against Leishmania infantum and tissue distribution in mice

Preliminary observations have shown that AmBisome, a liposomal formulation of amphotericin B (Vestar Inc.), is effective and non-toxic in animal and human visceral leishmaniasis. The activity of multiple doses of this drug on Leishmania infantum, in BALB/c mice was investigated, and amphotericin B concentration in liver and spleen was determined. Groups of infected mice were treated intravenously with 3, 5, or 7 doses of AmBisome (3 mg/kg) over 3, 10 and 25 days, respectively. The antileishmanial activity of the drug was compared with that of meglumine antimoniate (28 mg Sbv/kg per day over 21 days). Three consecutive daily doses of AmBisome were sufficient to clear all parasites from the liver of mice, while antimony did so only after 21 doses. Twenty-four-48 h after their last dose all the AmBisome-treated mice showed very high amphotericin B concentrations in liver (61.2-76.2 micrograms/g) and spleen (39.8-72.1 micrograms/g) with no overt signs of toxicity. Mice that received 2 or 4 doses at intervals of 5 to 8 days, maintained drug levels as high as those detected after 3 consecutive doses over 11 and 26 days, respectively. This should enable visceral leishmaniasis treatment on an intermittent or outpatient basis, thereby reducing overall treatment costs.

Decreased sensitivity to meglumine antimoniate (Glucantime) of Leishmania infantum isolated from dogs after several courses of drug treatment

Although unresponsiveness to antimonial drugs in human leishmaniasis appears to be increasing, resistance to antimony in Leishmania is not well documented. Treatment of leishmaniasis in dogs, the domestic reservoir of L. infantum, with meglumine antimoniate (Glucantime) is a common practice in many Mediterranean countries. The dogs, however, remain highly infective to the phlebotomine vectors, even after several courses of treatment. A study was therefore carried out to test the comparative susceptibility to meglumine antimoniate of L. infantum stocks isolated from four naturally-infected dogs, before (BT) and after treatment (AT) with three to six courses of the drug, and used to infect Balb/c mice. Significant differences in suppression between the BT and AT stocks were observed in the infected mice when they were given the drug at a rate of 0.01-10 mg kg-1 day-1 for five days. Each AT stock was between eight and 41 times more resistant to meglumine antimoniate than the BT stock from the same dog, in terms of the ratios of the AT ED50 values to the corresponding BT values, which were calculated as indices of resistance. This result underlines the futility and danger of repeated antimonial treatments of dogs with signs of leishmaniasis, as these may produce a permanent reservoir of parasites unsusceptible to the drugs in human clinical use.

Cytochrome b of protozoan mitochondria: relationships between function and structure

1. The sensitivity of ubiquinol:cytochrome c reductase to its most powerful inhibitors has been characterized in mitochondria from three ciliate and two trypanosome protozoans and compared with that in mitochondria of animals and plants. 2. Mitochondria of ciliates, particularly those of Tetrahymena pyriformis, are resistant to antimycin. 3. Mitochondria of trypanosomes are quite resistant to stigmatellin, as they exhibit a 40-fold higher titer than that in ciliate or animals mitochondria. 4. Both ciliates and trypanosomes are highly resistant to myxothiazol. 5. Correlations have been drawn between the natural resistance of the protozoan mitochondria to antimycin, stigmatellin and myxothiazol and peculiar features in the structure of their apocytochrome b, on the basis of an accurate alignment of the sequences of this protein.

[Macleod's syndrome as a cause of recurrent pneumonia in a child]

Macleod's syndrome is a rare cause of recurrent pneumonia in children. A case report is described and the diagnostic utility of chest roentgenogram and CAT is emphasized.

[The doses absorbed by the patients and the exposure of the operators in dental radiodiagnosis]

The present paper reports an updated dosimetry of dental radiology since it presents the data relative to 7 radiological techniques. The doses to 9 organs were measured on a Randoman phantom using TLD (4 in each chosen cavity) for lenses, tongue, cervical vertebrae (C2), thyroid, ovaries, uterus and testes. The examinations were subsequently repeated after applying X-ray shields to the phantom. The main conclusions follow: a) local doses are never negligible but can be really high, especially for tongue (1.880 mGy), thyroid (1.011 mGy), and C2 (0.699 mGy); b) X-ray shields for lenses, ovaries, uterus and testes have proven to be unnecessary; in a more general context, X-ray shields should be evaluated by the Health Physics Dept., especially relative to radiation leaks from the X-ray tube. As for the thyroid, X-ray shields have proven very useful but can result in repeated acquisitions because of possible interference with the radiological image; c) technicians' risk, in the present experimental conditions, does not exceed the threshold values recommended by Italian laws. At any rate, the use of fixed or mobile shieldings should always be evaluated while keeping in mind the specific working conditions in radiology departments.

The amino aldehydes produced by spermine and spermidine oxidation with maize polyamine oxidase have anti-leishmanial effect

Purified maize polyamine oxidase bound to hydroxylapatite was utilized as an enzymatic reactor to produce oxidized spermidine and spermine. The oxidation products showed a consistent inhibitory activity on Leishmania infantum in mice. 1,3-diaminopropane showed a much lower activity. Moreover chemically prepared 4-aminobutyraldehyde had a similar ED50 to that of oxidized spermidine. It is concluded that among the compounds arising from polyamine oxidation those with the greatest anti-leishmanial effect are 4-aminobutyraldehyde and 1-(3-aminopropyl)-4-aminobutyraldehyde.

[Sources of ionizing radiation in dwellings]

According to recent surveys made by the International Commission on Radiological Protection (ICRP) and the World Health Organization (WHO), it has been estimated that in temperate regions people spend only 20% of their time outdoors and spend the remaining 80% indoors (homes, schools, other buildings). It is therefore important to establish whether radiation sources exist inside buildings in order to assess risk for the population. The 238U and 232Th radioactive chains are of particular importance because of Radon and Radon daughter production and 40K as component of building materials. It has been estimated that about 4.5% of lung cancers observed in the population are associated with exposure to Radon daughters. In order to comply with international regulations it is estimated that 1.5% of the existing dwellings in temperate regions need to be improved.

Synthesis and antileishmanial activity of some 1- or 2-(dihydroxyalkyl) and 3-(dihydroxyalkoxy)pyrazolo [3,4-d] pyrimidines

Several new derivatives of 4-amino-, 4,6-diamino- and 4-hydrazino-[3,4-d]pyrimidine dihydroxyalkyl substituted in the 1 or 2 positions, or dihydroxyalkoxy substituted in the 3 position have been synthesized. Some of these compounds were evaluated for their activity against Leishmania infantum in mice. The highest degree of antileishmanial activity was displayed by the 4-amino-1-(dihydroxyalkyl) derivatives which yielded parasite inhibition values nearly comparable with that of glucantime in a standard 5-day test.

[The pathogenesis of arterial hypertension in diabetes mellitus and its role in nephropathy]

This paper synthesizes the pathogenic steps of arterial hypertension in diabetes mellitus: hyperosmolarity due to the hyperglycemia and increased sodic tubular reabsorption accounting for the expansion of the extracellular volume with hypervolemia; abnormalities of the ionic membrane pumps leading to abnormal intracellular calcium distribution, thereby inducing an increased vascular tone; atypical vasomotor reactivity to cathecolamines; modifications of the renin-angiotension-aldosterone system. The pathophysiological derangements by which hypertension could induce nephropathy are examined: the vasodilatation which can be detected from the onset of diabetes, may be a determinant in the transmission of systemic hypertension to the glomerular microcirculation with resulting enhancement of the hydrostatic transglomerular pressure gradient (i.c. the major factor producing glomerular injury), glomerular plasmatic flow and filtration rate. The nephron hyperfiltration increases the movement of plasmatic proteins across the glomerular capillary wall with subsequent mesangial hyperactivity and sclerosis. Antihypertensive treatment in diabetes follows general guidelines and it should be instituted even in the case of microhypertension being facilitated in this setting the appearance of microalbuminuria i.e. the starting point of nephropathy. Even if experimental studies are to favor ACE inhibitors as the first-line drugs for abating glomerular hypertension by mitigation of the direct effect of angiotensin II on the efferent arteriolar tone, clinical observations suggest that, regardless of type of treatment, the normalization of systemic arterial pressure, by reversing glomerular hypertension may be effective in preventing diabetic nephropathy.

[NIOBI-X filter: reduction of patient exposure and effect on image quality]

Patient protection against ionizing radiation has become more and more important and the subject has been included in all the latest ICRP publications. Recently a 50 microns Niobium filter (NIOBI-X) has come out, which, installed on tungsten anode X-ray apparatuses, allows patient dose reduction by absorbing the radiation which does not contribute to the image. In order to verify the NIOBI-X actual effect on image quality and on patient dose reduction, image resolution, image contrast and patient exposure (air-Kerma) were measured using a bone-equivalent stepped wedge. The NIOBI-X, added to the total filtration of the X-ray apparatus, allows an air-Kerma reduction of about 50% from 60 to 130 kV. In the case of bone-equivalent material exposure the filter causes a slight contrast loss and does not affect, or even improves, image resolution. Before choosing the NIOBI-X filter for all the X-ray apparatuses a cost-benefit analysis should of course be made by evaluating results and cost related to other kinds of filter. With particular regard to Aluminium filters, whose prices are far lower than Niobium ones, it has to be pointed out that: 1) in order to have the same air-Kerma reduction the Aluminium filter thickness must be quite heavy (2.8 mm) which causes practical problems of use; 2) the Aluminium filter causes image quality loss especially at lower kVs.

Sister chromatid exchanges in first-trimester chorionic villi after in vivo and in vitro exposure to diagnostic ultrasound

A study was done to evaluate the effects of diagnostic ultrasound on sister chromatid exchange (SCE) in first-trimester chorionic villi under controlled technical conditions. Chromosome analysis was performed by the direct method using spontaneous mitoses from the cytotrophoblast layer, and SCE visualization was accomplished by a 72 h treatment with 5-bromodeoxyuridine (BrdU) at a concentration of 10 micrograms/ml. The slides were stained with acridine orange. Immediately before first-trimester chorionic villus sampling, a group of ten pregnant women was exposed to diagnostic ultrasound for 20 min (in vivo exposure). This group of patients was compared with a control group who were not exposed. A mean value of SCE/cell frequency of 4.2 +/- 0.2 was found in the exposed pregnancies, while a value of 3.7 +/- 0.2 was observed in the control group. After in vitro exposure of chorionic villi obtained from elective abortions, the frequency of SCE/cell did not differ significantly among samples with different exposures (1, 2, and 3 h) and controls. The positive control (mitomycin C) yielded a significant increase in SCE frequency.

In vivo effect of eflornithine (DFMO) and some related compounds on Leishmania infantum preliminary communication

An in vivo method was used to test the effect of eflornithine (DFMO) and five related compounds on Leishmania infantum amastigotes. Treatment with 100 mg/kg sc for 5 days of Leishmania infected Balb/c mice yielded a parasite inhibition ranging from 56% (compound 2, "reverse arginine") to 85% (eflornithine), these values being lower than that obtained with the reference compound Glucantime (93%). In long-term treatment (40 days) the two selected compounds, eflornithine and 3 ("reverse homoarginine"), failed to cure the animals. However, in dose response experiments these drugs showed to be effective at very low doses when compared with Glucantime, thus suggesting that they might be of potential value in the chemotherapy of leishmaniases.