Enterotoxic effect of stool supernatant of Cryptosporidium-infected calves on human jejunum

BACKGROUND/AIMS

The clinical pattern of cryptosporidial diarrhea suggests an enterotoxic mechanism. No evidence for this mechanism has been reported thus far. This study aimed to look for enterotoxic effect elaborated by Cryptosporidium.

METHODS

The effects on human intestinal transport of stool supernatant of diarrheal calves infected with Cryptosporidium parvum were examined. Aliquots of centrifuged and filtered stools were added to the mucosal or serosal side of human jejunum obtained from patients undergoing surgery and mounted in Ussing chambers. Electrical parameters were recorded. Stool supernatants of uninfected calves served as a control.

RESULTS

The mucosal addition of 2.5 mg protein of fecal supernatant from diarrheal calves induced a prompt and significant increase in short circuit current with no effects on tissue conductance. The serosal addition of this material and the addition of control supernatant to either side did not induce modifications of electrical parameters. The enterotoxic effect was dose-dependent and saturable. It was reversible by withdrawing the supernatant from the incubation medium. The electrical effect was chloride- and calcium-dependent and was sensitive to heating.

CONCLUSIONS

An enterotoxic activity is present in the stools of Cryptosporidium-infected calves. This activity may be responsible for secretory diarrhea in humans.

Oral immunoglobulins for treatment of acute rotaviral gastroenteritis

OBJECTIVE

Preliminary evidence has been reported on the antirotavirus effect of human serum immunoglobulin administered orally. The aim was to see whether such treatment might be effective in rotavirus acute gastroenteritis.

METHODS

A prospective, double-blind, placebo-controlled study was performed. Ninety-eight children admitted with acute gastroenteritis were enrolled and randomly assigned to groups A (treated) and B (control). Children in group A received a single oral dose of 300 mg/kg body weight of human serum immunoglobulin. Parameters of efficacy were clinical condition, frequency and consistency of stools, duration of diarrhea, duration of viral excretion, and length of hospital stay. Antirotaviral activity was determined in the immunoglobulin preparation by a specific neutralization assay.

RESULTS

Seventy-one of the 98 children enrolled had rotaviral gastroenteritis; 36 belonged to group A. Children who received immunoglobulin had significantly faster clinical improvement of clinical condition and stool pattern than control children. Mean total duration of rotaviral diarrhea was 76 hours in group A and 131 in group B (P < .01). Viral excretion lasted 114 and 180 hours, respectively (P < .01). Hospital stay was significantly reduced in children in group A. Neutralizing antibodies against rotavirus were detected in the immunoglobulin preparation.

CONCLUSION

Oral administration of immunoglobulin is associated with a faster recovery from acute gastroenteritis and should be given to children hospitalized with this illness.

Familial erythrophagocytic lymphohistiocytosis: adverse prognostic significance of delayed diagnosis

Familial erythrophagocytic lymphohistiocytosis (FEL) is a rare disorder of the monocyte-macrophage system, for which an autosomal recessive mode of inheritance has been postulated. It is characterized by a dismal prognosis and is peculiar of early infancy. Three new cases of infants affected by FEL are reported. All three patients were diagnosed about three months after the onset of symptoms, and all three died shortly after diagnosis. The need for early diagnosis and prompt, intensive cytotoxic chemotherapy is emphasized.

[The organizational problems of the hospitals of the Nord Italia Transplant Program (NITp) engaged in the activities of organ retrieval for transplantation. The Collaborative Group of Resuscitation Anesthetists]

If the quality of results of organ transplantation in NITp is highly satisfactory, the same cannot be said for the number of transplants performed, which only cover 20-25% of the requirement. To understand the causes of organ shortage, a study group of Anaesthesiologists and Transplant Coordinators from the North Italy Transplant Program (NITp) investigated, through a questionnaire addressed to the Heads of 103 Intensive Care Units (ICU) in 92 Hospitals in the NITp area, some of the organizational problems linked to donor identification and treatment and to organ retrieval. The questionnaire took into consideration the number of possible donors identified in 1990, those retrieved and the causes for non retrieving organs and examined a number of variables linked both to retrieval and to ICUs and Hospitals organization. The results show that potential donors were 461: 143 (31%) were used, 138 (30%) were lost due to family opposition to organ donation, 192 (20%) for clinical reasons and 88 (19%) for organizational reasons. The latter figure represents 5% of non retrieval in the most active ICUs and increases to 50% in the Hospitals that had procured no donors in 1990. The main obstacles for ICUs to procure organ donors are: convey the Medical-Legal Committee, carry out of complicated administrative procedures, availability of round the clock specialized equipment for neurological assessment (especially for ICU outside Neurosurgical and Neurological departments), inadequate number of medical and nursing staff, most of all at night, and finally the difficulty in the management of non-traumatic cerebrovascular patients.

Interspecific plasmid transfer and modification of heat-stable enterotoxin expression by Klebsiella pneumoniae from infants with diarrhea

We have previously described two heat-stable enterotoxins (ST) produced by Citrobacter freundii and by Klebsiella pneumoniae. To see whether transfer of toxigenic ability may occur between different bacterial species, conjugal mating experiments were performed using strains isolated from children. Donors and recipients were incubated together. ST production by the recipients was tested by the suckling mouse assay, which is the standard biologic method for detecting ST, and also by an ELISA test. The latter is based on MAb directed to Escherichia coli 18- or 19-amino acid toxin. Citrobacter and E. coli strains producing an ELISA-positive ST were used as plasmid donors. Recipients were E. coli, Klebsiella P89, and Klebsiella AL55. The latter had been previously shown to be capable of producing an ELISA-negative ST, but had spontaneously lost this ability. After conjugation, all strains gave positive results in the suckling mouse assay. However, E. coli and Klebsiella P89 ST were positive in the ELISA test, whereas Klebsiella AL55 ST was negative. The same three strains were transformed by inserting the plasmid pSLM004 encoding an ELISA-positive ST. Klebsiella P89 and E. coli became capable of producing an ELISA-positive ST, whereas Klebsiella AL55 cells were positive in the suckling mouse assay but negative in the ELISA. To assess whether the toxigenicity acquired was itself transmissible, the new ST-producing strains were incubated with a nontoxigenic Citrobacter strain. The latter became capable of producing an ELISA-positive ST in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Comparative effects of atrial natriuretic peptide and E. coli heat-stable toxin on rat intestinal transport

Conflicting data have been published in favor of or against a secretory effect of atrial natriuretic peptide (ANP) in the intestine. The reported effects resemble that of Escherichia coli heat-stable enterotoxin (ST). In this work the effects of ANP were studied in well established experimental systems and compared with that of ST. Both peptides induced a prompt secretion of water, Na, and Cl with no effects on K net transport in the in vivo rat perfused jejunum. The addition of ST, but not of ANP, evoked an increase of short circuit current in rat intestinal mucosa mounted in Ussing chambers. ST induced a significant increase in guanylate cyclase activity in intestinal homogenates, whereas ANP showed no effect. No binding sites for ANP were detected in basolateral or brush border membranes, nor in isolated enterocytes by a suction filtration technique. In conclusion, ANP acts as a short-lived intestinal secretagogue in the rat. Its mechanism of action is different from that of E. coli ST and appears to be indirect, since is not mediated by specific intestinal receptors and is not evident in vitro.

Relationship between cognitive style and emotional behavior

In this research we examined the relationships among cognitive styles using the categorization of Bion and styles of modulation of emotional behavior (hostile content) explored with the Gottschalk, et al. method applied to the speech of 20 female and 10 male undergraduate students whose ages ranged from 20 to 35 years. Their verbalization was produced in a standard stimulus situation of 3 minutes duration. Analysis indicated a relationship between hostile attitude and cognitive styles. In particular, those who were relatively less hostile presented higher frequencies of processes classified by Bion as D2, which are characterized by an attitude of expectancy and waiting, with a tendency to defend internal psychological themas.

Reference values of the steatocrit and its modifications in diarrheal diseases

Conflicting results have been reported on the use of the steatocrit to measure fecal fat excretion. Aiming to assess the reliability of this method and its usefulness in the diagnosis of intestinal enteropathies, we measured the steatocrit in 747 healthy children and 442 children with diarrhea grouped according to diagnosis. The steatocrit was found to correlate strictly (r = 0.93) with the chemical measurement of fecal fat. Reference values and ranges were established. The maximal steatocrit was observed in neonates; afterwards, it progressively decreased to an undetectable level in children older than 2 years of age. A steatocrit abnormally high for age was found in 20% of patients with acute diarrhea and in 53% of those with chronic diarrhea. All celiac patients with a gluten-containing diet showed a marked increase of steatocrit. We conclude that the steatocrit is a reliable and easy-to-perform test, which quickly provides valuable information in the diagnostic workup of the child with diarrhea.

Impaired intestinal function in symptomatic HIV infection

A longitudinal (10-22 month) evaluation of intestinal symptoms and function was performed in five children with symptomatic human immunodeficiency virus (HIV) infection. All received cotrimoxazole, ketoconazole, and immunoglobulins. A search for enteric pathogens and intestinal function tests were repeatedly performed in all patients. Mild episodes of diarrhea were observed in two children. One had cow's milk protein intolerance. Giardia lamblia was found in an asymptomatic carrier. Evidence for impaired intestinal function was found in all patients. These consisted of positive D-xylose and iron oral loads, increased steatorrhea, increased fecal excretion of alpha 1-antitrypsin, abnormal intestinal permeability, and increased food antibody levels. Our results suggest that severe diarrhea may be uncommon in children with HIV infection receiving antimicrobial prophylaxis, but that the intestinal function is frequently, and often markedly, impaired.

[Group music therapy in the comprehensive management of psychosis]

In this paper the Authors propose the use of group music therapy as an integrated part of the treatment of severe mental illness: borderline and psychotic cases. The therapeutical techniques used and their aims are fully described. There are four phases of treatment in the evolution of group music therapy; these take place successively over time and are repeated each time a new patient enters the group: 1) a motor phase in which patients dance, play games with movement and do physical exercises; 2) a receptive phase based on listening to music; 3) an active phase during which they make music and sing; 4) and a predominantly verbal phase during which patients discuss the emotions, thoughts and fantasies experienced while listening to music within the group. Lastly, the paper put forwards and hypothesis based on the therapeutical function of listening to music, taking into account the clinical aspects and concepts of dynamic psychology.

Heat stable enterotoxin produced by Escherichia coli in acute diarrhoea

We screened 569 children with acute onset diarrhoea from five Italian towns for heat stable enterotoxin produced by Escherichia coli. We compared an enzyme linked immunoabsorbent assay (ELISA) with the standard suckling mouse assay for detection of the enterotoxin. A total of 31 (5.4%) children were found who had strains of E coli that produced heat stable enterotoxin: 26 strains were positive in both tests, four only in the suckling mouse assay, and one only in the ELISA. Compared with the suckling mouse assay the sensitivity of the ELISA was 87% and the specificity was 99.8%. The mean age of the children with E coli that produced heat stable enterotoxin was 22 months. Fifteen (48%) of the children had ingested potentially contaminated food and five (17%) had a previous contact with someone with diarrhoea. The clinical picture was milder than that described in developing countries. Faecal osmolality and the osmolal gap were consistent with a secretory diarrhoea in 12 out of 15 (80%) of these children. The mean duration of the diarrhoea was five days. Heat stable enterotoxin produced by E coli is a common cause of mild diarrhoeal illness in Italian children.

Characteristics and mechanism of action of a heat-stable enterotoxin produced by Klebsiella pneumoniae from infants with secretory diarrhea

Escherichia coli heat-stable enterotoxins (ST) are classified into STa and STb according to their physicochemical and biologic characteristics. STa induces diarrhea, activating the guanylate cyclase-cGMP system. ST-like enterotoxins can be produced by bacteria other than E. coli, including Klebsiella pneumoniae. A Klebsiella ST has previously been shown to share some chemical and immunologic characteristics with E. coli ST. Aiming to define better the nature of Klebsiella ST, we have screened 237 children with diarrhea and 179 controls for ST-producing Klebsiella, using the SMA. We detected 26 Klebsiella strains from patients, two of which were positive in the SMA, and 36 from controls, all negative for ST. A partial purification was performed using an acetone precipitation followed by ultrafiltration and gel filtration techniques. Klebsiella toxin was heat-stable, methanol-soluble, sensitive to mercaptoethanol, active at acid pH values, but not at pH greater than 8. The time course of Klebsiella toxin in the SMA resembled that of E. coli STa. Klebsiella ST caused reduced Na absorption and net Cl secretion in rabbit ileal mucosa mounted in Ussing chambers. It was found to increase the cGMP but not the cAMP concentration. Finally, Klebsiella ST did not react with anti-E. coli STa MAb in a competitive ELISA. We conclude that K. pneumoniae may induce diarrhea through the production of an STa similar but not identical to E. coli STa.

Citrobacter freundii produces an 18-amino-acid heat-stable enterotoxin identical to the 18-amino-acid Escherichia coli heat-stable enterotoxin (ST Ia)

We purified and sequenced the heat-stable enterotoxin produced by Citrobacter freundii. The toxin was detected during purification by reaction with monoclonal antibody to Escherichia coli heat-stable enterotoxin. The C. freundii toxin amino acid sequence was identical to that of the 18-amino-acid heat-stable enterotoxin (STa) produced by toxigenic E. coli.

Indirect mitotic nondisjunction in Vicia faba and Chinese hamster cells

The hypothesis of indirect mitotic nondisjunction was tested in plant and mammalian cells. This hypothesis states that micronuclei derived from lagging chromosomes or chromatids are able to perform DNA synthesis and undergo mitotic condensation synchronously with main nuclei. Hence, as chromosomes, they can be moved to spindle poles together with the chromosomes of the main nuclei during mitosis. In that way chromosomes "lost" as micronuclei can be reincorporated in the main nuclei. In order to test this, both Vicia faba meristematic cells and cells of a Chinese hamster line (Cl-1) were treated with low doses of colchicine. Mitotic anomalies, micronuclei and cells with a polyploid or aneuploid karyotype were scored at different fixation times. A detailed analysis was performed on single chromosome misdistributions, as well as on micronuclei and cells with aneuploid karyotypes derived from single chromosome misdistributions. Indirect mitotic nondisjunction was shown to play a primary role in the origin of aneuploid karyotypes in Vicia faba, but not in Cl-1 cells.

Age-related differences in receptors for Escherichia coli heat-stable enterotoxin in the small and large intestine of children

Escherichia coli that produce heat-stable enterotoxin are a worldwide cause of diarrheal disease, especially in children. We examined small and large intestinal specimens from children of various ages for the presence of E. coli heat-stable entero-toxin receptors and determined whether the number of receptors or the binding affinity of these receptors was related to the age of the child. We observed specific binding of 125I-heat-stable enterotoxin to all small intestinal and colonic specimens. However, a greater number of receptors per microgram of membrane protein were present in infants and the number of receptors rapidly decreased with increasing age. We also observed that increased heat-stable enterotoxin stimulation of guanylate cyclase was correlated with increased receptor density. We suggest that a greater number of gastrointestinal receptors for heat-stable enterotoxin, capable of activating more guanylate cyclase, may contribute to the increased severity of diarrhea noted in young children exposed to enterotoxigenic E. coli.

T84 cell receptor binding and guanyl cyclase activation by Escherichia coli heat-stable toxin

Escherichia coli heat-stable enterotoxin (STa) induces intestinal secretion by binding to enterocyte receptors and activating the guanylate cyclase-guanosine 3',5'-cyclic monophosphate (cGMP) system. The intermediate steps between binding of STa and secretion are poorly understood, due in part to the lack of a convenient system to study the effects of STa at the cellular level. To establish such a model, we investigated the binding of 125I-STa, STa activation of guanylate cyclase, and STa-induced increase in cGMP production in a well-characterized human colonic cell line, T84. Binding was specific, linear with cell number, and time, temperature and pH dependent, and reversible. ST may also be internalized by these cells. Addition of unlabeled STa competitively inhibited binding of 125I-STa. These parameters closely resemble those described in intact rat enterocytes and cell-free membrane preparations. STa stimulated guanylate cyclase and cGMP production in a dose-related manner. The similar dose-response relationships for binding, guanylate cyclase stimulation by STa, and cGMP production suggest that the guanylate cyclase-cGMP system is coupled to ST occupancy of specific receptors. These data, together with the fact that STa induces chloride secretion from T84 cells suggest that T84 cells are a suitable and convenient system to study the cellular mechanism of action of STa.

Binding of E. coli heat-stable enterotoxin to rat intestinal brush borders and to basolateral membranes

We studied the binding of E. coli heat-stable enterotoxin (STa) to rat brush borders (BB) and to basolateral membranes (BLM) using a biologically active monoiodinated radioligand [( 125I]STa) and highly enriched BB and BLM preparations free of other significant organelle contamination. Binding of [125I]STa to BB was specific; time-, temperature-, and pH-dependent; saturable; and partially reversible. Nonlabeled toxin competitively inhibited the binding of radioligand to BB in a dose-related manner. Scatchard analysis revealed a single class of receptors with an apparent affinity constant of 8.7 +/- 1.5 X 10(8) l/mol. Binding was not affected by amino acids, sugars, and lectins. Proteolytic enzymes significantly decreased binding, although several did so by modifying the radioligand. Trypsin inhibited binding without modifying the radioligand thus supporting the proteinaceous nature of the receptor. Since the enrichment in binding activity in the BB over the homogenate was significantly lower than the enrichment in sucrase activity, we concluded that binding activity is probably associated with other membranous domains, but direct examination revealed no binding activity on basolateral membranes.

Small and large intestinal guanylate cyclase activity in children: effect of age and stimulation by Escherichia coli heat-stable enterotoxin

Heat-stable enterotoxin (ST) producing Escherichia coli are a common cause of diarrhea in infants. ST acts through the stimulation of the guanylate cyclase-cGMP system. The effect of ST on the human intestine has not been investigated nor is any information available on the activity, distribution, or development of guanylate cyclase activity in the human intestine. The purpose of this study, therefore, was to characterize, these aspects of guanylate cyclase activity and to study the effect of ST on the activity and responsiveness of guanylate cyclase in the intestine of infants and children of various ages. We measured guanylate cyclase activity in 35 intestinal specimens, obtained operatively, from children aged 1 day to 16 yr. Guanylate cyclase activity was linear with protein concentration and time. Basal activity was similar in small intestine and in colon. In the small intestine, however, basal guanylate cyclase activity varied with age. It was maximal in children 1 day of age, and although somewhat variable, decreased with age thereafter. In colon, an age-related pattern was not found. E. coli ST stimulated guanylate cyclase activity in all specimens in a dose-related manner. In the small intestine ST-stimulation of guanylate cyclase was twice that found in colon. Furthermore, age affected the response of small intestinal guanylate cyclase to ST. Maximal response to ST was observed in children 1 day of age and ST stimulation was significantly greater in children less than 1 yr of age than in older children. In the colon, the response of guanylate cyclase to ST did not change with age.(ABSTRACT TRUNCATED AT 250 WORDS)

[Does CDDP have radiosensitizing properties in the treatment of solid tumors in advanced stage?]

Various experimental and clinical studies have signalled the radiosensitizing properties of CDDP (Cis-dichloro diammine platinum). Twenty eight patients with advanced solid tumours were included in a pilot study incorporating classic fraction (2.00 Gy X 5 weeks) radiotherapy and weekly doses of 30 g/sq.m CDDP. A complete response was obtained in 21 patients with 11 of them NED at a mean follow-up period of 4-16 months. The toxicity of the treatment was low and no kidney damage or ototoxicity was encountered. The results obtained by the combined treatment are encouraging but a correct assessment will require a randomised trial on a bigger patient sample.

Production of Escherichia coli STa-like heat-stable enterotoxin by Citrobacter freundii isolated from humans

Citrobacter species are often present in the stools of children and are generally considered a normal component of the intestinal microflora. Previous reports suggested that they might act as enteric pathogens. Aiming at defining the role of Citrobacter species in inducing diarrhea, we looked for their presence in the stools of 328 children with diarrhea and in 108 controls. Citrobacter strains were isolated from 46 patients (14%) and 7 controls (6.5%) (P less than 0.05). All isolates were tested for heat-stable (ST) and heat-labile (LT) enterotoxin. No LT-producing organisms were found. Three C. freundii strains, all isolated from children with diarrhea, elaborated an enterotoxin detected by the suckling mouse assay. A crude extract was prepared by acetone precipitation and a sequential ultrafiltration technique. The enterotoxin was heat stable, and its estimated molecular weight was between 2,000 and 10,000. Citrobacter enterotoxin was soluble in methanol and stable at acid and neutral pHs but not above pH 8, and its activity was destroyed by treatment with 2-mercaptoethanol. Citrobacter enterotoxin was inactive in the 18-h rabbit ileal loop test. All these characteristics closely resemble STa produced by Escherichia coli. The time course of Citrobacter enterotoxin-induced intestinal secretion in suckling mice was similar to that of E. coli STa. The enterotoxin produced by C. freundii cross-reacted with monoclonal antibodies raised against E. coli STa. These results suggest that C. freundii is capable of inducing diarrhea through the production of an E. coli-like STa, and its presence in the stools of patients with diarrhea should be considered as that of a possible etiologic agent.

Detection of clostridial toxins in stools from children with diarrhoea

A cell-culture assay was used to detect toxins directly in stools from sporadic cases of infantile diarrhoea. Cytotoxins were revealed in 11 out of 58 samples from children with diarrhoea, nine of whom had no common enteric pathogens in their stools. A preliminary characterisation of the cytotoxins was obtained by neutralisation tests with clostridial antitoxins.

[Kinesitherapy in lumbago]

Since most back pain syndromes are due to excessive and long-lasting incorrect postures, we think that such illness may benefit from kinesiotherapy. There must be considered 2 types of back pain: disc pain and static pain. We advise to patients various self control techniques and muscle potentiating gymnastics. Besides these techniques, other adjuvant therapies may be prescribed.

[Diagnostic support of arthrographic study in recent sprains of the ankle]

The Authors assert, through the valuation of forty recent cases of ankle injury, submitted to the arthrographic research, the validity of such method for the valuation of ligament injuries and for the topographic orientation of the same injuries.

Acute childhood diarrhoea in Naples: an aetiologic study

A potential aetiologic agent was detected in the stools of 56% of 118 children hospitalized in Naples for acute diarrhoea. Rotavirus and Salmonella were the agents most commonly associated with disease, accounting for 23 and 17 percent of cases, respectively. Campylobacter jejuni, enterotoxigenic Escherichia coli, Yersinia and Shigella were less frequently isolated (total, 11% of cases). These findings fit well with the epidemiological picture described for other developed countries, except for the isolation rate of Salmonella which widely exceeds that reported in other investigations. Cytotoxic strains of E. coli and other Gram-negative bacilli were identified in the stools of 18 children; the possible pathogenic role of these strains is unknown and needs further investigation.

Chronic diarrhea and failure to thrive in an infant with Campylobacter jejuni

We report the case of an infant with chronic diarrhea and failure to thrive. Campylobacter jejuni was isolated from stools and treatment with erythromycin resulted in eradication of infection and prompt resolution of symptoms. A 22-month-old girl was referred to our University Hospital because of weight loss and chronic diarrhea, which did not respond to repeated dietetic trials that excluded milk, gluten, and other foodstuffs. Microscopic examination of the jejunal biopsy specimen revealed a mild degree of partial mucosal atrophy with inflammatory infiltrates in the lamina propria without any hallmarks of celiac disease. Repeated stool cultures on Butzler medium were positive for C. jejuni. This finding was associated with a high titer of specific serum antibodies. Erythromycin therapy without any other form of therapy led to prompt improvement, and the patient reached her "own" 50th centile as weight/height ratio. The aim of this report is to alert pediatric gastroenterologists of the possibility that Campylobacter may be associated with chronic diarrhea and failure to thrive.

Enteric infections, cow's milk intolerance and parenteral infections in 118 consecutive cases of acute diarrhoea in children

One hundred and eighteen consecutive cases of childhood acute diarrhoea (mean age: 10.5 months) were studied after admission to our Pediatric Unit in Naples over a 13-month period. A diagnosis was established in 92 patients (78%): 55% of patients were found to have an infectious enteritis (among them, 5 had ETEC infections and 1 had an ST-producing Klebsiella infection), 12% a parenteral infection, 11% cow's milk intolerance. The occurrence of gross blood (P less than 0.01), leukocytes, and reducing substances in the stools was more commonly associated with infectious enteritis than with diarrhoea due to all other causes. In 14 patients (8 of whom were malnourished), diarrhoea ran a prolonged course. In all, the eventual outcome was favourable. Our findings, while confirming that infectious enteritides account for most of acute diarrhoeas in children, stress the importance of parenteral infections and cow's milk intolerance in this condition. Also, the need for an accurate search for enterotoxigenicity of enterobacteria before ruling out their pathogenetic role is stressed.

[Hyperbaric oxygen therapy in the treatment of various orthopedic disorders]

A Hyperbaric oxygen therapy (HOT) unit was set up some months ago in the Anaesthesia Service of the Galeazzi Orthopaedic Institute in Milan. HOT can be used in a number cases which are not relevant to the present report. In the field of Orthopaedics and Traumatology HOT in isolation or in association has proved useful in the following field: acute and chronic osteomyelitis; infected and non-infected pseudoarthroses; slow bone-knitting following limb lengthening or high risk fractures; local oedemas and disturbed scarring. Cases of patients sent to hospitals and Centres specialising in the treatment of all the above pathologies are presented. The results are highly encouraging given the high percentage of cures and the rapidity with which they were obtained. HOT has the added advantage of not requiring long-term hospitalization, since patients can be treated in outpatient departments.

[Stages of hyperbaric oxygenation therapy in the healing process of lesions of superficial tissues]

The histopathological background to the healing process in lesions of the superficial tissues is described briefly and the effect of oxygen at various stages in this process is examined. The propriety of using hyperbaric oxygen therapy in certain types of lesion is discussed and the most effective therapeutic approaches are suggested.

[Hyperbaric oxygen therapy in radionecrotic lesions]

The Anaesthesia and Recovery Service at the Galeazzi Orthopaedic Centre in Milan has an HOT unit where various cases of necrosis following radiotherapy for neoplasias have been and are still being treated. Some cases of radiodermitis and osteoradionecrosis only cured after HOT treatment are presented. The recovery of the scarring and granulation processes in these cases is attributable to the increased perfusion and above all diffusion of oxygen which activates the heating processes in the hypoxic tissues. An additional advantage of HOT is that patients can be treated in outpatients department (for periods ranging from 25 to 70 days according to the seriousness of the case), thus avoiding long-term hospitalisation and withdrawal from normal working life.

[Considerations on collateral treatments used with hyperbaric oxygenation in the therapy of gas gangrene]

The devastating nature of gas gangrene has in the past necessitated radical surgery to prevent the destructive spread of the disease. The advent of antibiotics only partly reduced the need for radical amputations and distressing multilations. Immediate, extensive surgery has now been reduced to a minimum thanks to Hyperbaric Oxygen which rapidly dominates the toxicity of Clostridium. Experience shows that it is still, unfortunately, necessary to emphasize the futility of certain ill-timed and often exaggeratedly multilating surgical approaches, which have at times utterly nullified the clearly positive results obtained by HOT in three cases of post-traumatic gas gangrene.

[Comparative analysis of radiographic data of "structural changes" in the bones of divers and non-divers]

The Authors examine one thousand lone bone X-rays of professional divers and non-diving controls. The goal is to look for a correlation between hyperbaric exposure and bone alteration images type "dense bony islet" and "translucent cystic area" according to McCallum, Walder and Davidson. The results show a statistically non significant difference between divers and controls: Hip: Divers 31%, Controls 30%; Knee: Divers 17%, Controls 23%; Shoulder: Divers 22%, Controls 22.5%. The types of bone structural alterations studied never seemed to originate forms of aseptic bone necrosis but had a tendency to evolve favourably and independently from diving activity. These structural alterations are therefore deemed as non significant with regard to the bone risk of professional diving. The Authors suggest that until the real significance of these bone X-ray images is cleared by further research only the bone structural alteration which are within one centimeter from the articular surface should be considered for possible negative evolution.

["Pseudomonas aeruginosa" in the hospital of Avellino, and the presence of colonies in the obstetric, pediatric and neonatal wards. A microbiological and epidemiological study (author's transl)]

Two episodes of unexpected and widely spread colonisation of Pseudomonas aeruginosa in a hospital urged us with a series of measures concerning personnel and environmental hygiene and prophylaxis. We referred on the microbiological researches made on nine stories of the hospital building in which the microorganism settled and the countermeasures were adopted. The isolates proved to have a strong resistance to the various types of disinfectant we used and it was particularly difficult to clean wash-hand-basins and some medical tests. The AA. think that carefully instructing the staff in the hospital on bacterial biology and their channel of diffusion, and on the appropriate measures to avoid and fight them, could give better results compared to those we actually obtain by simply disinfecting the environment.

Uptake of 67Ga-6-mercaptopurines in Morris hepatoma-3924 A

67Ga-chloro-6-mercaptopurine and 67Ga-citrato-6-mercaptopurine complexes have been prepared and their distribution in Morris-hepatoma-3924 A-bearing rats studied. The tumour affinity of the gallium-67 compounds varies in the order: 67Ga-chloro-6-mercaptopurine greater than 67Ga-citrato-6-mercaptopurine greater than 67Ga-citrate greater than 67Ga-chloride.