[Investigation in medical technology: support for cooperation among countries]

This paper discusses the results of the research work on medical technology in several countries by research teams whose goals are to prompt the exchange of information and support practical cooperation. Emphasis is placed on the work developed by the Pan American Health Organization, which has supported 45 research proposals on medical technology and stimulated the association of academic groups, national institutions and international agencies. The authors also describe the research activities of the team devoted to medical technology research at the National Institute of Public Health in Mexico.

Traumatic interhemispheric subdural haematomas

According to reports in the literature traumatic interhemispheric subdural haematomas (I.S.H.) are supposed to present acutely or subacutely with contralateral monoparesis of a lower extremity or hemiparesis or in bilateral haematomas even with paraparesis, and to need early operative evacuation. In our series of 5 cases none of them followed this "classical" clinical picture, and three of them recovered without operation. We conclude that the indication for operative evacuation depends on the clinical course and that in patients with spontaneously improving symptomatology non-surgical management under close supervision may be the better solution. Also the C.T. finding of open convexity cisterns may be possible indication for conservative management.

MutM, a protein that prevents G.C----T.A transversions, is formamidopyrimidine-DNA glycosylase

We have cloned chromosomal DNA bordering an insert that inactivates mutM. Sequencing of this clone has revealed that the insertion element is located between the promoter and structural gene for formamidopyrimidine-DNA glycosylase (Fapy-DNA glycosylase). An overproducing clone of Fapy-DNA glycosylase complements the original mutM strain that had been isolated after EMS mutagenesis. Thus, we conclude that MutM is actually Fapy-DNA glycosylase. mutM has previously been characterized as a mutator strain that leads specifically to G.C----T.A transversions. This in vivo characterization correlates well with the mutagenic potential of one of the lesions Fapy-DNA glycosylase removes, 8-oxo-7,8-dihydro-2'-deoxyguanine (8-OxodG).

Neuronal localization of pyroglutamate aminopeptidase II in primary cultures of fetal mouse brain

Pyroglutamate aminopeptidase II is a highly specific membrane-bound ectopeptidase proposed to inactivate thyrotropin releasing hormone (TRH) in brain extracellular space. Its activity was measured in primary cell cultures of fetal brain in an attempt to define its cellular localization. Enzyme activity was detected in hypothalamic or cortical cell membrane fractions from 4- to 12-day-old cultures. When proliferation of nonneuronal cells was abolished by cytosine arabinoside treatment, pyroglutamate aminopeptidase II specific activity was increased as compared to untreated cultures, the opposite was observed for pyroglutamate amino-peptidase I activity. Treatment of cortical cells with the neurotoxic agent glutamate reduced simultaneously pyroglutamate aminopeptidase II and glutamate decarboxylase activities. Glial cell cultures expressed pyroglutamate aminopeptidase I or glutamate synthase activities but not pyroglutamate aminopeptidase II. The data suggest that pyroglutamate aminopeptidase II is predominantly localized in neuronal cells. This is consistent with a role for pyroglutamate aminopeptidase II in TRH-ergic synaptic transmission.

[Clinical diagnosis versus autopsy]

Records from 910 autopsies performed at a university hospital in Salvador, Bahia, Brazil were examined in order to assess the accuracy of clinical diagnoses of the patients' underlying causes of death. This study found inaccurate clinical diagnoses in 31% of the cases. The overall rate of diagnostic error appeared to remain fairly stable from 1970 to 1982, being highest for older patients. Thirty-six percent of the 263 cancer deaths were incorrectly diagnosed, and a number of pathologies considered relatively easy to diagnose were not always correctly identified--the underlying cause of death being incorrectly diagnosed in many of the fatalities caused by such ailments as arterial hypertension, chronic obstructive lung disease, pneumonia/bronchopneumonia, and schistosomiasis. Quite aside from their direct medical implications, diagnostic errors of the magnitude observed in this and other studies seriously jeopardize the quality of vital statistics and such statistics' usefulness for improving public health.

Urinary excretion of renin and angiotensinogen in nephrotic rats

Puromycin aminonucleoside (PA)-nephrotic rats have a high plasma renin activity (PRA) and low angiotensinogen levels. We measured proteinuria, urine renin, and urine angiotensinogen daily, for 11 days after PA injection. Proteinuria and urine angiotensinogen were evident on day 5, and urine renin on day 6. Peak levels of urine renin and angiotensinogen were attained on day 8. These data suggest that angiotensinogen urine excretion may contribute to its low plasma levels, and urine renin loss may limit a further increase in PRA.

Comparative study of the fatty acid composition of sponges of the genus Ircinia. Identification of the new 23-methyl-5,9-tetracosadienoic acid

1. The phospholipid fatty acid compositions of the sponges Ircinia strobilina, Ircinia felix, Ircinia campana, Ircinia sp., Spongia tubulifera and Dysidea etherea were studied, revealing the presence, besides other common fatty acids, of considerable amounts (2-5%) of the novel 23-methyl-5,9-tetracosadienoic acid (1). 2. The demospongic acids 5,9-tetracosadienoic acid, 23-methyl-5,9-tetracosadienoic acid (1), and 5,9-pentacosadienoic acid, were particularly abundant in sponges of the genus Ircinia, in contrast to the most common 5,9-hexacosadienoic acid found in other species. These findings are discussed in terms of the taxonomy of the Dictyoceratida. 3. The complete characterization of the novel phospholipid fatty acid 23-methyl-5,9-tetracosadienoic acid (1) is presented.

Spinal cord hemangioblastoma with subarachnoid hemorrhage

A case of subarachnoid hemorrhage caused by a cervical hemangioblastoma is presented. The clinical picture was indistinguishable from that of a subarachnoid hemorrhage from an intracranial lesion. The diagnosis was established by angiography and water-soluble contrast myelography followed by cervical computed tomographic scan. At surgery, the tumor was completely removed, and no neurological deficit was observed after the operation.

mutA and mutC: two mutator loci in Escherichia coli that stimulate transversions

Two transversion-specific mutator loci, mutA and mutC, were identified in Escherichia coli. Mutators with high rates of A.T----T.A transversions were identified using a screening technique that relied upon the reversion of an altered lacZ gene back to wild-type via a specific A.T----T.A transversion. Among the mutators collected, one class mapped to a previously unidentified locus that we designate mutA. Analysis of reverse mutations in lacZ and forward nonsense mutations in lacI showed that the mutA strain has higher levels of A.T----T.A and G.C----T.A transversions, and to a lesser degree A.T----C.G transversions. The mutA locus maps very near to, but is separable from, mutL, at about 95 min on the E. coli chromosome. Both its mutagenic specificity and complementation experiments confirmed that mutA is distinct from mutL and from a nearby mutator locus, miaA. The phenotype of a mutA mutL double mutator strain suggests that the mutA gene product prevents some replication errors. Another mutator, designated mutC, maps very near uvrC, at 42 min, but is distinguishable from uvrC, which has no mutator effects. The specificity of reversion of lacZ mutations in a mutC strain is identical to that in a mutA strain. Also, the behavior of a mutC mutS double mutant is identical to that of a mutA mutL double mutant. It is likely that mutA and mutC are components of the same error-avoidance system.

Angiotensin I-converting enzyme activity in puromycin aminonucleoside-nephrotic syndrome

Puromycin aminonucleoside (PAN)-nephrotic rats have high serum angiotensin I-converting enzyme (ACE) activity. We studied ACE activity in serum, urine, and tissues from PAN-nephrotic rats on days 2, 6, 11, and 16 after PAN injection. Proteinuria and hypoproteinemia were evident on days 6 and 11. Though significantly decreased, proteinuria was still evident on day 16. Serum ACE activity increased on days 2, 6, and 11. Urinary ACE activity became evident on days 6, 11, and 16 and correlated positively with proteinuria, suggesting that the source of urine ACE is the blood serum. ACE activity increased in testis on days 2 and 6, in lungs and aorta on days 6 and 11, in adrenal glands and small intestine on day 11, and in kidney on days 11 and 16. Heart ACE activity decreased on days 2 and 6, and increased on day 16; brain ACE activity decreased on day 6 and increased on day 11. These data implicate that changes in tissue ACE content may contribute to elevate serum ACE in PAN-nephrotic rats.

[Manifestations of paralytic ileus in infants hospitalized for acute diarrheal syndrome]

In order to assess and characterize adynamic ileus (AI) complicating acute diarrhoea (AD) in infants, 802 consecutive admissions were studied. Diagnosis was suspected in 23 patients with abdominal distension and confirmed by radiological study in 16 whose age range was 14 ds to 6 mo. Of these late patients, 9/16 were malnourished. Age was less than, but nutritional status similar to that of all patients admitted with ADD. Vomiting (14/16), silent or almost silent abdomen (10/16), protracted course of diarrhoea (9/16) and increased gastric content (6/16) were the most common clinical findings in addition to abdominal distension and X Ray films suggestive of AI (inclusion criteria). Lack of constipation was a relevant finding. Treatment included temporal discontinuance of oral feedings, intravenous fluids administration, nasogastric and rectal tube and antibiotics. Lethality rate was 4/16. Duration of AI was an average of 2 days in survivors and 4 days in the remainder infants. It is concluded that AI is an infrequent complication of AD (0.19% of cases), which should be suspected in infants less that 6 mo old with diarrhoea and abdominal distension.

Evaluation of the role of prolyl endopeptidase and pyroglutamyl peptidase I in the metabolism of LHRH and TRH in brain

Intraneuronal peptide regulatory mechanisms are still poorly understood. The cytosolic enzymes prolyl endopeptidase (EC 3.4.21.26) and pyroglutamyl peptidase I (E.C.3.4.19.3) degrade both TRH and LHRH. Previous studies from this laboratory have not supported a role for these enzymes in the control of TRH levels. These studies have now been extended to cell and organ cultures and examine the effects of enzyme inhibition on LHRH. Exposure of dispersed hypothalamic cells or median eminences in culture to Z-Pro-Prolinal and pyroglutamyl diazomethyl ketone, specific inhibitors of prolyl endopeptidase and pyroglutamyl peptidase I respectively, did not change TRH content or recovery of released TRH. In vivo and in vitro treatment with these inhibitors did not modify the content of LHRH or recovery of this peptide upon release from several brain regions except in the olfactory bulb where an unexpected decrease in levels was observed. Olfactory bulb levels of TRH also decreased but only after prolonged in vivo inhibitor treatment. The decrease in olfactory bulb LHRH and TRH could not be accounted for by enzyme induction and is likely due to a non-specific or indirect effect of the inhibitors on the processing of these peptides. These studies demonstrate that levels of LHRH and TRH in brain are not controlled by cytosolic peptidases.

Serotype-specific outbreak of group B meningococcal disease in Iquique, Chile

From 1979 to August 1987, there have been 178 cases of meningococcal disease in Iquique, Chile, a city of about 140,000. The attack rate for the last 5 years has been in excess of 20/100,000 per year, more than 20 times greater than for the country overall. The mortality rate was 6%. The disease occurred in patients with ages from 4 months to 60 years, but 89% of cases were in patients less than 21 years. The largest number of cases were in the age group 5-9 years (n = 54), but the highest incidence occurred in children less than 1 year of age (72.8/100,000 per year). The male/female ratio was 1.2. Cases occurred all year round with little seasonal variation. Of the 178 cases, 173 were biologically confirmed. Serogroup analysis of strains from 135 patients revealed A = 1, B = 124, C = 10. Forty-four group B strains from 1985-7 were serotyped: 15:P1.3 = 36, 15:NT = 4, 4:P1.3 = 2, NT:NT = 2. Ten of 11 of the outbreak strains tested were sulfadiazine-resistant. This is the first recognized outbreak caused by a Gp B:15 strain in South America. It shares many of the characteristics of outbreaks caused by closely related strains in Europe, such as a predilection for older children and adolescents, sulfadiazine-resistance, and sustained high attack rates. The Iquique strain (B:15:P1.3) belongs to the same genetic clone (ET-5 complex) as the Norway (B:15:P1.16) and the Cuban (B:4:P1.15) strains.

MutY, an adenine glycosylase active on G-A mispairs, has homology to endonuclease III

The mutY gene of Escherichia coli, which codes for an adenine glycosylase that excises the adenine of a G-A mispair, has been cloned and sequenced. The mutY gene codes for a protein of 350 amino acids (Mr = 39,123) and the clone genetically complements the mutY strain. The protein shows significant sequence homology to E. coli endonuclease III, an enzyme that has previously been shown to have glycosylase activity on damaged base pairs. Sequence analysis suggests that, like endonuclease III, MutY is an iron-sulfur protein with a [4Fe-4S]2+ cluster.

Pathophysiology of experimental nephrotic syndrome induced by puromicyn aminonucleoside in rats. III. Effect of captopril, an angiotensin converting enzyme inhibitor, on proteinuria and sodium retention

The effect of the converting enzyme inhibitor (CEI) (captopril, 50 mg/kg/day) on proteinuria (UProt), urinary aldosterone (UAldoV), plasma renin activity (PRA), plasma renin concentration (PRC), plasma angiotensinogen concentration (PAC), urinary sodium (UNaV), serum total protein, and body weight was studied for 21 days in an experimental nephrotic syndrome (NS) model induced in rats by a single injection (15 mg/100g) of puromycin aminonucleoside (PA). The effect of captopril on control rats without NS was also characterized. In control rats, captopril increased PRC and PRA, and decreased PAC; it had no effect on UNaV, UAldoV, UProt, total serum protein and body weight. In rats with NS, captopril had no effect on sodium retention, hypoproteinemia, and UProt; it abolished the increased UaldoV and favored weight loss. Captopril also rose PRA and PRC, and decreased PAC in PA-nephrotic rats; these changes were similar to those produced by captopril in control rats. The mortality rate was higher in nephrotic rats treated with captopril (37%) than in untreated nephrotic rats (13%). It is concluded that captopril has no beneficial effects on the course on NS induced by PA during the first 21 days, and supports the contention that sodium retention is not related to the renin-angiotensin-aldosterone system activity in these rats.

A set of lacZ mutations in Escherichia coli that allow rapid detection of specific frameshift mutations

We have used site-directed mutagenesis to alter bases in lacZ near the region encoding essential residues in the active site of beta-galactosidase. The altered sequences generate runs of six or seven identical base pairs which create a frameshift, resulting in a Lac- phenotype. Reversion to Lac+ in each strain can occur only by a specific frameshift at these sequences. Monotonous runs of A's (or of T's on the opposite strand) and G's (or C's) have been constructed, as has an alternating -C-G- sequence. These specific frameshift indicator strains complement a set of six previously described strains which detect each of the base substitutions. We have examined a variety of mutagens and mutators for their ability to cause reversion to Lac+. Surprisingly, frameshifts are well stimulated at many of these runs by ethyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine and 2-amino-purine, mutagens not widely known to induce frameshifts. A comparison of ethyl methanesulfonate, N-methyl-N'-nitro-N-nitrosoguanidine and 2-aminopurine frameshift specificity with that found with a mutH strain suggests that these mutagens partially or fully saturate or inactivate the methylation-directed mismatch repair system and allow replication errors leading to frameshifts to escape repair. This results in a form of indirect mutagenesis, which can be detected at certain sites.

Serum angiotensin converting enzyme activity and plasma renin activity in experimental models of rats

1. Serum angiotensin converting enzyme activity (ACEA) and plasma renin activity (PRA) were determined in rats under different experimental conditions such as: nephrotic syndrome (NS), bilateral nephrectomy (BN), renovascular hypertension (RH), dehydration (DEH), anaesthesia (AN), low sodium diet (LSD) and high sodium diet (HSD), and injection with propranolol (PRO) and isoprenaline (ISO). 2. PRA increased in LSD, AN, NS, RH, DEH and IPT groups, and decreased in HSD, BN, and PRO groups. Serum ACEA did not change in RH, HSD, IPT, DEH, AN, and PRO groups, increased in NS group, and decreased in LSD and BN groups. 3. Serum ACEA changed in the opposite direction to PRA only in the LSD group. This finding suggests that ACE may limit the full expression of the renin-angiotensin system in the LSD group, but not in the other groups.

Pathophysiology of experimental nephrotic syndrome induced by puromycin aminonucleoside in rats. II. In vitro release of renin, angiotensinogen and aldosterone

In vitro release of renin, angiotensinogen and aldosterone was studied in control (CT) and nephrotic rats. Nephrotic syndrome (NS) was induced by a single injection of puromycin aminonucleoside (PA). The in vitro systems used were: renal cortical slices (RCS), liver slices (LS) and adrenal glands, all incubated in Krebs-Ringer buffer. Renal renin content (RRC) and isoproterenol-induced renin secretion (RS) also were studied. RS, RRC and angiotensinogen release were measured indirectly by radioimmunoassay (RIA) of angiotensin I (ANG I); aldosterone was estimated by direct RIA. Basal RS was not modified in NS: 385 +/- 196 (CT) vs 344 +/- 149 ng ANG I/mg protein/h (NS), p greater than 0.05. Isoproterenol increased RS significantly in both CT and NS groups: 535 +/- (CT) and 685 +/- 231 ng ANG I/mg protein/h (NS) (p less than 0.05 vs. basal RS). RRC was similar in both groups: 2.17 +/- 0.62 (CT) vs 2.05 +/- 0.49 micrograms ANG I/mg protein/h (NS), p greater than 0.05. Angiotensinogen release from LS increased in nephrotic rats from 10 +/- 3.2 (CT) to 12 +/- 1.9 pmoles angiotensinogen I/mg tissue/2h (NS), p less than 0.05. Aldosterone release increased markedly from adrenal glands of rats with NS (1649 +/- 1111 pg aldosterone/mg tissue/h) with respect to control rats (257 +/- 85), p less than 0.05 In vitro studies were performed six days after PA-injection, when nephrotic rats had ascitis, edema, proteinuria, hypoproteinemia, hypercholesterolemia, hypertriglyceridemia, low sodium and aldosterone excretion, low levels of plasma angiotensinogen and high levels of plasma renin and aldosterone.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathophysiology of experimental nephrotic syndrome induced by puromycin aminonucleoside in rats. I. The role of proteinuria, hypoproteinemia, and renin-angiotensin-aldosterone system on sodium retention

The pathophysiology of the nephrotic syndrome (NS), characterized by protenuria, edema, sodium retention and hyperlipidemia, is not clear. We studied the role of some systemic factors on sodium retention in an experimental model of NS. NS was induced in rats by a single subcutaneous injection of puromycin aminonucleoside (PA) (15 mg/100 g); control animals received vehicle. All rats were kept in metabolic cages for 24 days (3 days before and 21 days after PA-injection). Urine was collected daily. Blood samples were obtained every day until day 10, and then every other day up to the end of the study. The rats showed the following alterations after PA injection: a) a rise in serum angiotensin converting enzyme activity (ACEA) and plasma aldosterone (PAldo) at day 1; b) a rise in urinary aldosterone (UAaldoV), azotemia and sodium retention at day 2; c) massive proteinuria (UProt) and decrease in plasma angiotensinogen concentration (PAC) at day 4; d) increases in plasma renin activity (PRA), plasma renin concentration (PRC) and serum creatinine as well as hypoproteinemia, hypercholesterolemia, hypertriglyceridemia, ascitis and edema at day 5; e) increase in urine volume at day 6. PAldo became normal at day 7; urine sodium (UNaV), PRA and PRC at day 8; UAldoV at day 9; serum urea and ACEA at day 10; urinary volume at day 11; PAC, serum total protein and creatinine at day 12. The edema disappeared at day 11. UProt, hypercholesterolemia and hypertriglyceridemia persisted, though they decreased substantially by the end of the study (day 21). Light microscopy studies revealed normal glomerular morphology, but electron microscopy showed fusion of podocytes before proteinuria. These data suggest that: a) sodium retention was not a consequence of proteinuria or hypoproteinemia; b) sodium retention seems non-related to renin secretion, but may be partially mediated by a fall in glomerular filtration rate or by an increased tubular resabsorption secondary to other factors; c) the increase in PAldo, UAldoV and ACEA are non-related to renin secretion: all occurred before PRA rose; d) water retention, increase in PRA and PRC, hypercholesterolemia and hypertriglyceridemia are secondary to the hypoproteinemia.

Porencephalic cyst in pycnodysostosis

We describe a case of pycnodysostosis with porencephaly and suggest an explanation for the porencephaly by a mechanism of imbalance between brain growth and its vascular supply and a normal but unopposed cerebrospinal fluid pressure.

Underreporting of AIDS cases in South Carolina, 1986 and 1987

An evaluation of the completeness and accuracy of case reporting of the acquired immunodeficiency syndrome (AIDS) for the 18-month period from January 1, 1986, through June 30, 1987, was conducted for South Carolina. A total of 596,585 hospital discharge billing records were searched by computer for conditions defining AIDS. The resulting 1513 records were manually reviewed. Of these, 349 discharges for 163 individuals were classified as being definitely AIDS related, the clinical features of these cases meeting Centers for Disease Control criteria for AIDS diagnosis. Of these cases, 153 were reportable to the South Carolina AIDS registry at the time of their diagnosis. Comparison of this case list with registry records revealed that only 91 (59.5%) had been reported. Reporting was significantly poorer for cases among blacks (53.1%) than for cases among whites (71.6%). These findings may have important implications for the interpretation of AIDS surveillance data and for planning activities in which awareness of complete case counts may be critical.

Non-productive or thalassemic-like heavy-chain gene rearrangement in a K-chain CLL clone

Information obtained from the study of immunoglobulin (Ig) gene rearrangement in different types of lymphoproliferative disorders has led to the suggestion that Ig gene activation obeys a precise hierarchy in which heavy-chain gene rearrangement procedes light-chain gene recombination. However no information is available on the mechanism(s) controlling this sequential activation. We report here a case of CLL which suggests that the expression of the heavy-chain genes is not necessary for light-chain gene rearrangement, or that very low amounts of heavy-chain mRNA and/or heavy chains are sufficient to activate k-chain genes.

[Intracellular messengers in the regulation of renin secretion]

The intracellular messengers that seem to be involved in renin secretion (RS) from juxtaglomerular cells (JG) are calcium (Ca), cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). Unlike the majority of secretory systems, an increase in intracellular Ca concentration and calmodulin and protein kinase C activation inhibit RS. The intracellular Ca concentration in JG cells can be modified if: 1) the normal mechanisms of Ca extrusion of these cells is altered; 2) the calcium output is blocked by lanthanum; 3) the function of the voltage-sensitive Ca-channels is modified; 4) uptake or liberation of Ca from endoplasmic reticulum is modified; 5) plasmatic membrane is bypassed with calcium ionophores such as A 23187. 6) JG cells are stimulated by hormones that increase Ca and activate protein kinase C such as angiotensin II, vasopressin or alpha-1 adrenergic agonists; 7) extracellular Ca concentration increases or decreases. RS is stimulated by dibutyryl cAMP, cAMP phosphodiesterase inhibitors and by hormones and agents that activate adenylate cyclase (beta adrenergic agonists, bradykinin, histamine, forskolin and ethylcarboxamide adenosine). On the contrary, RS is inhibited by hormones and agents that inhibit adenylate cyclase such as: alpha-2 adrenergic agonists, neuropeptide Y, angiotensin II and cyclohexyladenosine. Pertussis toxin increases basal RS, blocks the inhibition by agents and hormones which inhibit adenylate cyclase and potentiate the stimulation produced by beta-adrenergic agonists. In JG cells, atrial natriuretic peptide inhibits RS, increases cGMP and decreases cAMP. The increase in cGMP correlates well with the inhibition of RS.

The peritoneoscopic implantation of a polyurethane percutaneous access device for peritoneal dialysis. Preliminary experience

The short-term experience with peritoneoscopic implantation of eight Dermaport devices is discussed. These eight devices were implanted using local anesthesia and utilizing a modification of the Y-TEC method of catheter implantation. Excellent immediate function was observed universally allowing catheter use for dialysis and good skin-device interface; however dialysate leakage occurred within 2 to 4 weeks in four patients. Lack of permanent bonding between the catheter and the adjustable proximal cuff, resulting in suboptimal or slow ingrowth of tissue around it, appears to be the cause of this phenomenon.

Abnormal Papanicolaou smears after earlier smears with atypical squamous cells

From November 1984 to January 1986, 138 women were seen in our cervical clinic with atypical squamous cells in a referring cervical Papanicolaou smear. We obtained a second smear and performed a careful pelvic examination, microscopic examination of the vaginal secretions and endocervical culture for the gonococcus. The time interval between the smear showing atypical squamous cells and the one performed in our clinic ranged from 1 to 12 months. The Papanicolaou smear from 59 (50%) of the 117 women who had it repeated within four months returned abnormal as compared to 5 (24%) of the 21 repeated after four months (P = .04). Of 41 women with persistent atypical squamous cells, 10 (24%) had a clinically detectable vaginal infection, while only 3 (4%) of the 74 women with a normal repeat smear had an infection (P less than .01). These findings suggest an association between cervical cytology showing atypical squamous cells and vaginal infections. Nevertheless, this cytologic diagnosis should not be dismissed lightly since a high percentage of women with atypical squamous cells on cytology are found to have dysplasia on colposcopically directed biopsies. The most appropriate method of evaluating these patients has yet to be determined. If the clinician elects to follow these patients with serial Papanicolaou smears, the ideal interval between smears needs to be defined. Our data suggest that an interval of four to six months would be the most efficient.

Effects of bepridil on calcium release from rat heart mitochondria

Bepridil at concentrations above 10 microM, and at pH 7.2 stimulates calcium release from rat heart mitochondria. However this action is different from that of ClCCP, an uncoupler of oxidative phosphorylations, since it is ruthenium red insensitive. At lower concentrations bepridil may inhibit the Na-induced calcium release. The effects of bepridil depend on the pH and indicate that the protonated form of the drug is more efficient on calcium release than the basic form.

Protective effects of bepridil on calcium injury of anoxic myocytes isolated from adult rat heart ventricular muscle

Cardiac myocytes allowed to recover after the isolation procedure in a well-oxygenated medium were resistant to an extracellular Ca++ concentration of 1.5 mM. At least 90% of the isolated myocytes maintained their initial rod-shaped form after a 1-hr incubation, as well as 85% of their ATP and a low cellular content of calcium. At concentrations less than 10(-5) M, bepridil had no effect on these cells. On the other hand, when the myocytes were incubated in anaerobic conditions, 1.5 mM Ca++ was deleterious: the number of viable cells decreased by about 50%, ATP levels were lowered by 70% and the total cell calcium content increased by more than 100%. Bepridil had a biphasic effect on anaerobic cells. At concentrations below 10(7) M, the drug had a beneficial action. It restored cell viability and cellular ATP to 77 and 100% when compared to their respective level in the absence of Ca++. However, at concentrations higher than 10(-6) M, bepridil decreased the number of viable cells as well as their ATP content. At optimal concentrations, bepridil lowered the cellular calcium to its level in aerobic conditions. Without calcium addition, anoxic cells accumulated Na+ and lost K+. Calcium addition decreased Na+ accumulation by 68% and prevented the loss of K+. The Na+ and K+ content of the cells were not affected by bepridil. However, it is noteworthy that, at 10(-4) M, bepridil decreased dramatically the potassium content of the cells. In aerobic conditions, the calcium resistance of isolated ventricular myocytes may still be enhanced by Fluozol, a fluorocarbon compound which increases oxygen solubility in water.

Clinical and CSF cyto-proteic findings in 23 patients with CSF eosinophilia

Clinical diagnosis and cerebrospinal fluid (CSF) protein pattern were studied in 23 patients who had eosinophilic granulocytes in the CSF. Clinical data revealed that an inflammatory disorder of the central nervous system (CNS) was evident in 20 cases. A lymphoid reaction and elevated CSF total protein were found in most of the cases, but the most important finding was an increase of CSF gamma-globulin in 12 patients, of whom 10 had oligoclonal patterns. Our results may give support to a relationship between intrathecal eosinophilic reaction and inflammatory diseases of the CNS with subacute or chronic course accompanied by intrathecal synthesis of immunoglobulins.

Blood pressure response to changes in serum ionized calcium during hemodialysis

The effect of an increasing serum ionized calcium concentration on blood pressure during hemodialysis was studied in a prospective cross-over trial. Twelve patients were dialyzed three times with a dialysate Ca concentration of 5.5 mg/dL and three times with one of 7.5 mg/dL. Dialysis with the high Ca dialysate was associated with less fall in the mean arterial pressure (p less than 0.001). No statistically significant changes occurred in serum osmolality, body weight, or heart rate after dialysis at the two dialysate Ca levels. Increasing the Ca concentration in dialysate may protect against intradialytic hypotension in some patients.

Contrast media for angiography: effect on renal function

A total of 125 patients with severe peripheral vascular disease were examined with translumbar aortography. The mean dose of contrast medium injected was 65 ml of Angio Conray (containing 31.2 g of iodine). Forty patients were pretreated with mannitol, and 32 received furosemide. Thirty-eight patients (30%) had diabetes and, presumably, diabetic nephropathy. Eleven of them had significant azotemia (creatinine values greater than or equal to 4 mg/dl). Administration of contrast material did not significantly reduce renal function in any patient group. We conclude that acute renal failure following the injection of contrast material is uncommon, is reversible, and almost always occurs when avoidable complicating factors are present.

Taurine and hypotaurine inhibit light-induced lipid peroxidation and protect rod outer segment structure

Exposure of isolated frog rod outer segments to light (5000 lux) induces membrane disorganization and swelling. An increase of about 50% on lipid peroxidation, measured by the extent of malonaldehyde formation, accompanied the light-induced damage. Taurine and hypotaurine (25 mM) prevented the increase in lipid peroxidation, and provided an entire protection of rod outer segment structure.

Double infection of the CNS with herpes simplex and mumps viruses. Serological and ultrastructural studies

Clinical, serological and ultrastructural features are described in a case of acute encephalitis. The ultrastructural study of brain biopsy specimens revealed herpes-and paramyxovirus-like particles in neurons and glial cells that were characterized as herpes simplex and mumps viruses by serological study in serum and CSF. Of the few cases previously reported with double encephalitis, this is the only one in which ultrastructural and serological evidence of combined brain infection has been found.

Local immunoglobulin synthesis and blood-brain barrier assessment in subacute sclerosing panencephalitis

The immunoglobulin synthesis within the central nervous system and the blood-brain barrier (BBB) function were evaluated in 6 patients with subacute sclerosing panencephalitis (SSPE) using the IgG index and a graphic method based on serum/CSF albumin, alpha 2-macroglobulin, and IgG quotients. A strong local production of IgG was documented by both methods in all 6 cases of SSPE. Concerning the graphic analysis, the decrease in the serum/CSF alpha 2-macroglobulin ratio disclosed BBB dysfunction in 2 cases of SSPE, suggesting, in the absence of the serum/CSF albumin quotient abnormalities, that a homeostatic mechanism for CSF proteins can cause changes in the CSF protein profile.

Protective effect of taurine and zinc on peroxidation-induced damage in photoreceptor outer segments

Exposure of isolated frog rod outer segments (ROS) to ferrous sulfate in a Krebs-bicarbonate medium causes a time-dependent disruption of the membrane organization of the discs. Ferrous sulfate also causes ROS swelling and aggregation. Addition of taurine (5-20 mM) and zinc sulfate (250 microM) to the incubation medium markedly protected ROS from the disrupting effect of ferrous sulfate. Of other amino acids tested, only beta-alanine had a protective effect on ROS structure. Ferrous sulfate caused an increase in lipid peroxidation, measured by malonaldehyde formation. The protective effect of taurine and zinc is not accompanied by a reduction of lipid peroxidation. Water accumulation occurs as a consequence of the peroxidative action of ferrous sulfate, and this effect was counteracted by taurine and zinc. Ferrous sulfate did not cause damage to ROS structure when incubation was carried out in sucrose-HEPES. Sodium, chloride, and bicarbonate ions caused ferrous sulfate to disrupt ROS structure. It is concluded that taurine and zinc protect ROS membranes from ion and/or water entry occurring as a consequence of membrane lipid peroxidation.

Cerebellar cortex ultrastructure in ataxia-telangiectasia

An ultrastructural study of a biopsy fragment from the cerebellar cortex of a patient with ataxia-telangiectasia was performed. There was a sharp reduction in the number of Purkinje cells and an increase in the number of Golgi epithelial cells. Despite the degeneration of Purkinje cell dendrites, the volumetric density of parallel fiber varicosities and the number of synapses in the molecular layer were only slightly reduced. No qualitative nor quantitative abnormalities were noted in the granular layer. An analysis is made of the severe changes in cerebellar circuitry of this patient and their probable functional implications.

Renal parenchymal disease: sonographic-histologic correlation

A retrospective study of 109 patients who underwent renal biopsy was designed to correlate the sonographic appearance of the kidney with the histologic changes and clinical and laboratory findings in various renal parenchymal diseases. The clinical, pathologic, and sonographic data were analyzed blindly and independently by a team from each corresponding discipline. There was no correlation between the specific sonographic appearance and the type of renal disease. There was a significant correlation between renal length and the prevalence of global sclerosis, focal tubular atrophy, and the number of hyaline casts per glomerulus. A significant positive correlation was also found between cortical echogenicity and the severity of global sclerosis, focal tubular atrophy, the number of hyaline casts per glomerulus, and focal leukocytic infiltration. While there was overall significant correlation between the degree of cortical echogenicity and blood urea nitrogen and creatinine concentrations in each group, a wide range of variance was present. It is not currently feasible to distinguish different types of renal medical disorders using diagnostic ultrasound.

Cell-mediated immunity in chronic myelocytic leukemia

14 patients with chronic myelocytic leukemia were evaluated immunologically; no difference was found in mean lymphocyte percentage and absolute number between patients and healthy subjects. 4 cases (28.5%) showed decreased percentage of T lymphocytes, while only 2 cases (14.2%) had decreased absolute T lymphocyte values. PHA transformation was decreased in 57% of the patients. Spontaneous transformation in the short-term cultures exceeded the normal range in 65% of the cases. All patients skin tested were found to be reactive. Most of the patients had defective cellular immune response in vitro, probably related with a qualitative defect in T lymphocyte subpopulations. It cannot be completely excluded that part of the observed lymphocyte depression was due to the busulfan.