Short atrioventricular delay reduces the degree of mitral regurgitation in patients with a sequential dual-chamber pacemaker

This study was performed in a population of sequential dual-chamber pacemaker-patients with isolated mitral regurgitation (MR) to identify the "ideal atrioventricular (AV) delay" and to determine the effect of sequential pacing with the ideal AV delay on MR degree. Twenty consecutive patients (age 69 +/- 7 years; 45% men) hospitalized at our institution for symptomatic III degree AV block and isolated MR were studied. All received a dual-chamber pacemaker programmed in DDD at a rate of 70 pulses/minute. The ideal AV delay was selected using echo-color Doppler parameters; it was defined as that resulting in a lower degree of MR and in the highest cardiac output. The mean "optimal short" AV delay resulted in 98 +/- 7 ms. At short AV delay we observed a significant reduction in MR severity (regurgitant fraction from 48 +/- 12% to 25 +/- 10% and jet area from 15 +/- 2 to 9 +/- 2 cm2; p <0.0001) together with an increase in stroke volume (68 +/- 16 vs 88 +/- 15 ml; p = 0.007) and mitral early-to-late peak velocity ratio (0.79 +/- 0.33 vs 1.38 +/- 0.37; p <0.0001). In conclusion, a short AV delay may be used to improve cardiac output in sequential paced patients with pure, isolated MR.

Parasitic sinusitis and otitis in patients infected with human immunodeficiency virus: report of five cases and review

We describe five cases of parasitic sinusitis and otitis in patients infected with human immunodeficiency virus (HIV) and review 14 reported cases. The pathogens identified in our group of patients included agents such as Microsporidium, Cryptosporidium, and Acanthamoeba species. The clinical features common to these patients included a long history of HIV seropositivity associated with advanced immunosuppression and multiple opportunistic infections as well as long-standing local symptoms refractory to multiple courses of antibacterial agents. Symptoms often included fever and chills in addition to local tenderness and discharge. Invasive diagnostic procedures were necessary to obtain the final diagnosis and to initiate appropriate therapy. Although most patients responded at least partially to specific therapy, relapses and recurrences were frequent in patients who did not receive long-term suppressive therapy. The general outcome for HIV-infected patients with parasitic sinusitis and otitis was poor; however, deaths were generally associated with other complications of the underlying HIV infection.

[Chronic pancreatitis. A recent national experience with its surgical management]

BACKGROUND

The prevalence of chronic pancreatitis in Chile is not known and there is no local information about the surgical treatment of this disease.

AIM

To review retrospectively the results of surgical treatment of chronic pancreatitis.

MATERIAL AND METHODS

The charts of 17 patients (12 male), aged 7 to 65 years old, with chronic pancreatitis that were operated in three different Chilean regions, were reviewed.

RESULTS

Seven patients had previous endoscopic therapeutic procedures (papillotomy in 4 and stent placing in 3). Seven patients had been subjected to previous biliary surgical procedures. Indications for surgery were severe pain in 14 patients, the suspicion of a pancreatic carcinoma in 4 patients, an infected pseudocyst in one and massive bleeding of multiple pseudo-aneurysms in a pseudocyst in one patient. Twelve patients were subjected to decompressions and 5 to pancreatic resections. There was no operative mortality and one transient pancreatic fistula. After an average follow up of 22 months, pain improved in 94% of cases, pancreatic cancer was diagnosed in one patient and 79% of subjects gained weight. One patient became insulin dependent, one increased his insulin requirements and one had transient steatorrhea, since she could not afford pancreatic enzyme replacement therapy.

CONCLUSIONS

The multidisciplinary approach of patients with chronic pancreatitis, with selective use of surgery, may greatly improve their quality of life.

Different dysregulations in adrenal steroid biosynthesis as a prevalent cause of hyperandrogenism in women from southern Italy

OBJECTIVE

To investigate the presence of a dysregulation in steroid biosynthesis in women from southern Italy.

DESIGN

Controlled clinical study.

SETTING

Normal and hyperandrogenic women referred to the Endocrinology Unit of Federico II University Medical School of Naples.

PATIENT(S)

One hundred fifty untreated young hyperandrogenic women and 50 normal age-matched women.

INTERVENTION(S)

Morning (basal) blood samples obtained in the early follicular phase and after a long (360 minute) ACTH stimulation test.

MAIN OUTCOME MEASURE(S)

The adrenal maximal response was calculated as stimulus under curve areas (AUCa), and all steroids were assayed using RIA methods.

RESULT(S)

A dysregulation of 21-hydroxylase was found in 22 patients (14.7%), with a prevalent increase of 17 alpha-hydroxyprogesterone AUC, whereas in 9 hirsute women (6%), there was a prevalent significant increase in 11-deoxycortisol AUC. In 5 women (3.3%), DHEA and DHEAS basal and AUCs plasma levels were increased, suggesting an impaired 3 beta-olo-dehydrogenase activity. The remaining 114 hyperandrogenic women (76%) compose the nonadrenal group, with a probable diagnosis of primitive functional ovarian hyperandrogenism.

CONCLUSION(S)

Considering the high prevalence of hirsutism and oligomenorrhea in our female hyperandrogenic population, we suggest an adrenal hyperresponsiveness likely due to a dysregulation in enzymes related to androgen adrenal steroidogenesis.

Evidence for a physiological role of central calcitonin gene-related peptide (CGRP) receptors in the control of food intake in rats

In the present study, we investigated the role of central calcitonin gene-related peptide (CGRP) and amylin receptors in mediating the anorectic effects of CGRP and amylin in rats chronically cannulated in the lateral brain ventricle. Intracerebroventricular (ICV) injection of the CGRP and amylin receptor antagonist CGRP(8-37) failed to influence the anorectic effects of peripherally injected CGRP and amylin. CGRP(8-37) alone, however, increased food intake in food deprived rats when administered 2 h before food presentation. Under the same experimental conditions, the more specific amylin receptor antagonists amylin(8-37) or AC 187 did not affect food intake. We therefore conclude, that CGRP is a physiological regulator of food intake within the central nervous system, acting at central CGRP receptors. Peripheral receptors, however, are likely to mediate the anorectic effects of peripherally administered amylin and CGRP.

Piggy-back versus conventional technique in liver transplantation: report of a randomized trial

Liver transplantation with preservation of the recipient vena cava (the "piggy-back" technique) has been proposed as an alternative to the traditional method. We performed a randomized study on 39 cirrhotic patients, 20 who underwent the piggy-back technique (group 1) and 19 the traditional method using venovenous bypass (group 2) to evaluate the feasibility and true advantages of the piggy-back technique compared to the traditional method. Two patients were switched to the conventional technique due to the presence of a caudate lobe embracing the vena cava in one patient and a caval lesion in the other. Statistically significant differences between the two groups were only found for the warm ischemia time (48.5 +/- 13 min for piggy-back vs 60 +/- 12 min for the conventional method) and for renal failure (zero cases in group 1 vs four cases in group 2). We therefore believe that liver transplantation with the piggy-back technique can easily be performed in almost all cases, and that only a few, specific situations, such as a very enlarged caudate lobe, do not justify its routine use.

[Changes in serum levels of N-terminal procollagen type III propeptide as an index of postinfarction ventricular remodeling]

The levels of aminoterminal propeptide of type III procollagen (PIIINP) can be used as an index of collagen breakdown. The aim of our study was to evaluate modifications in serum concentration of PIIINP (PIIINPs) in patients with a first episode of myocardial infarction. We examined 70 patients admitted at our Institution for acute myocardial infarction and 10 normal subjects. PIIINPs dosage was obtained by radioimmunoassay method utilizing a commercial available kit. All patients underwent three PIIINPs dosages: within 24 hours after admission, at 6 and 12 months after myocardial infarction. Control values were 0.4 +/- 0.1 U/ml. In 38 patients (Group I) PIIINPs levels increased at 6 and 12 months after infarction: 0.53 +/- 0.2, 0.75 +/- 0.2 and finally 0.76 +/- 0.1 U/ml. In the remaining 32 patients (Group II) PIIINPs values increased at 6 months and then returned to baseline at 12 months: 0.56 +/- 0.2, 0.75 +/- 0.1 and then 0.46 +/- 0.1 U/ml. The end-diastolic volume index did not change significantly in Group I (from 93.7 +/- 21 to 79.7 +/- 20 ml/m2) while it decreased after 12 months in Group II (from 88.9 +/- 13 to 58.6 +/- 11 ml/m2; confidence interval 95% from 2 to 55 ml/m2; p = 0.03). Similarly, there was no significant variation in end-systolic volume index (ESVI, from 39.7 +/- 11 to 36.9 +/- 11 ml/m2) and ejection fraction (from 60 +/- 10 to 59 +/- 15%) in Group I; while in Group II ESVI decreased significantly (from 33.6 +/- 13 to 20 +/- 5 ml/m2, confidence interval 95% from 3 to 24 ml/m2; p = 0.02) and ejection fraction improved (from 62 +/- 11 to 72 +/- 15%; confidence interval 95% from -20 to -1%; p = 0.04). In conclusion, patients with elevated levels of PIIINPs at 12 months did not improve ventricular function while patients with PIIINPs returning to baseline at 12 months had an improvement. Our results suggest an active participation of newly formed collagen in post-infarct ventricular remodeling. Therefore PIIINPs may be a marker of this process.

Functional characterization of the T4 DNA ligase: a new insight into the mechanism of action

ATP-dependent DNA ligases are essential enzymes in both DNA replication and DNA repair processes. Here we report a functional characterization of the T4 DNA ligase. One N-terminal and two C-terminal deletion mutants were expressed in Escherichia coli as histidine- tagged proteins. An additional mutant bore a substitution of Lys159 in the active site that abolished ATP binding. All the proteins were tested in biochemical assays for ATP-dependent self-adenylation, DNA binding, nick joining, blunt-end ligation and AMP- dependent DNA relaxation. From this analysis we conclude that binding to DNA is mediated by sequences at both protein ends and plays a key role in the reaction. The enzyme establishes two different complexes with DNA: (i) a transient complex (T.complex) involving the adenylated enzyme; (ii) a stable complex (S.complex) requiring the deadenylated T4 DNA ligase. The formation of an S. complex seems to be relevant during both blunt-end ligation and DNA relaxation. Moreover the inactive His-K159L substitution mutant, although unable to self-adenylate, still possesses AMP-dependent DNA nicking activity.

Food-associated drinking in pygmy goats: importance of histamine receptors

The combined effect of the histamine receptor antagonists Dexbrompheniramine (DXB: H1-receptor antagonist) and Cimetidine (C: H2-receptor antagonist) on food and water intake was investigated in pygmy goats. DXB (1 mg/kg BW0.75) and C (16 mg/kg BW0.75) were injected together intraperitoneally (i.p.). Cumulative food and water intake, as well as meal and draft pattern, were recorded. DXB and C significantly reduced cumulative water intake, whereas cumulative food intake did not change. Water to food ratio was also significantly diminished. Draft frequency and the percentage of drafts associated with meals were significantly reduced during the 6 h post injection, while meal frequency and meal size did not change during this period. The results show that blockade of the H1- and H2-histamine receptors attenuates the association between water and food intake in pygmy goats. Therefore, mechanisms responsible for meal-associated drinking seem to depend upon activation of histamine receptors.

Left atrial size is the major predictor of cardiac death and overall clinical outcome in patients with dilated cardiomyopathy: a long-term follow-up study

HYPOTHESIS

This study was undertaken to determine whether echo-derived left atrial dimension and other echocardiographic, clinical, and hemodynamic parameters detected at the time of entry into the study may influence prognosis in patients with dilated cardiomyopathy during a long-term follow-up.

METHODS

This was a prospective cohort analysis of 123 patients with dilated cardiomyopathy. Clinical evaluation, chest x-ray, M-mode and two-dimensional echocardiogram, exercise test, 72-h ambulatory electrocardiogram monitoring, and cardiac catheterization study were performed in all patients. The study was divided into two phases: in the first phase, patients were divided into two groups according to the left atrial size (> or = 45 mm; < 45 mm), with cardiac death as the end point. In the second phase, all patients were further divided into two groups according to their clinical course. A multivariate analysis was performed to determine independent correlated parameters of cardiac mortality and overall clinical outcome.

RESULTS

Cardiac mortality rate was 47.9%: 29% in the group without left atrial dilation and 54.3% in the group with dilated left atrium. Multivariate analysis revealed that left atrium > or = 45 mm, New York Heart Association functional classes III/IV, and the presence of one or more episodes of ventricular tachycardia at Holter monitoring were independent predictors of cardiac mortality, while left atrium > or = 45 mm, left ventricular end-diastolic pressure > 17 mmHg, and exercise tolerance < or = 15 min were independent predictors of poor clinical outcome.

CONCLUSIONS

Our results revealed that left atrial size is the principal independent predictor of prognosis in patients with dilated cardiomyopathy in that patients with left atrial dilation had an increase in mortality and a worse clinical outcome compared with those without left atrial dilation.

Effect of duration of ampullary gallstone obstruction on severity of lesions of acute pancreatitis

BACKGROUND

This study was done to determine the effects of duration of obstruction on severity of lesions in patients with acute pancreatitis of biliary origin.

STUDY DESIGN

This case controlled study used patient data collected prospectively on protocol during a 27-year period in a university teaching hospital. We studied a group of 97 patients with acute pancreatitis, all with an impacted stone at the ampulla of Vater at exploration (Group Ob), and a control group of 49 patients with acute gallstone pancreatitis who experienced spontaneous ampullary disobstruction within 24 hours from the onset of symptoms and who showed a patent ampulla at exploration (Group Cont). Duration of obstruction was defined as the time elapsed between the onset of symptoms and exploration in Group Ob, and from the onset of symptoms until the appearance of signs of ampullary disobstruction in Group Cont. Severity of disease in both groups was determined by the appearance of the pancreas at exploration. Patients in Group Ob were divided into three subgroups according to duration of obstruction: under 24 hours, 25 to 48 hours, and more than 48 hours.

RESULTS

The incidence of severe pancreatic lesions was higher in Group Ob than in Group Cont (19.7 percent compared to 6.1 percent, p < .01). Mean duration of obstruction was also significantly longer in Group Ob than in Group Cont (42.4 hours compared to 10.6 hours). In the subgroups of patients whose obstruction lasted under 48 hours, the incidence of severe lesions was low: in the 24 hours or fewer group, severe lesions were observed in 8.1 percent (3 of 37); and in the 25 to 48 hours group, the incidence was 10.6 percent (5 of 47). Neither subgroup differed significantly from Group Cont (6.1 percent, 3 of 49). When duration of obstruction exceeded 48 hours, however, frequency of severe lesions increased significantly to 84.6 percent (11 of 13) (p < .001).

CONCLUSIONS

The findings in this study suggest that duration of ampullary obstruction is a major factor determining the severity of pancreatic lesions: severe pancreatic lesions are rare in patients whose obstruction lasts not more than 48 hours. In contrast, pancreatic necrosis develops in nearly all patients with obstruction beyond 48 hours. It may be safe to treat patients conservatively during the first day of the illness. If obstruction is not resolved by the second day, endoscopic retrograde cholangiopancreatography or surgical intervention must be carried out.

Relationship between atrial function, left ventricular isovolumic relation time, and early filling in dual chamber-paced patients

This investigation was performed to study atrial systolic function is response to modification of atrioventricular delay in a sample of 36 patients with a DDD pacemaker implanted for complete atrioventricular block. The relation between atrial systolic performance and diastolic-related parameters was also evaluated. Isovolumic relaxation time, early diastolic peak velocity, late (atrial) diastolic peak velocity, atrial filing fraction, and atrial ejection force were recorded at a pacing rate of 70 impulses/min and at atrioventricular delay of 200, 150, and 100 msec. Our data showed that the progressive shortening of atrioventricular delay induced a gradual increase in early peak velocity (median value 46 to 53 to 61.5 cm/sec, respectively, at 200, 150, and 100 msec intervals) and a gradual decrease in isovolumic relaxation time (median 92.6 to 81.5 to 69.7 msec at 200, 150, and 100 msec, respectively), atrial peak velocity (59 to 52 to 44.5 cm/sec at 200, 150, and 100 msec, respectively), atrial filling fraction (50.5% to 40% to 23.5% at 200, 150, and 100 msec, respectively), and atrial ejection force (17.2 to 14.7 to 8.5 kilodynes at 200, 150, and 100 msec, respectively). For every atrioventricular delay value detected, we found a significant correlation between isovolumic relaxation time and early peak velocity with atrial filling fraction and atrial ejection force. In addition, atrial ejection force was related directly to atrial filling fraction at studied atrioventricular delays. The two indexes of atrial systolic performance showed a parallel decrease by shortening the atrioventricular delay, and they can quantify atrial systolic performance equally in sequentially paced patients. Furthermore, our results are in accordance with the hypothesis that the interaction between the effectiveness of active left atrial emptying and isovolumetric relaxation time may play an important role in maintaining an ideal ventricular filling despite changes in atrial systolic function.

Quiescence, cycling, and turnover in the primitive hematopoietic stem cell compartment

Continuous oral bromodeoxyuridine (BrdU) administration was used for the non-invasive measurement of the in vivo cell cycling characteristics of hematopoietic stem and progenitor cell populations of increasing maturity, isolated on the basis of their relative levels of Rhodamine 123 (Rh) and Hoechst 33342 (Ho) fluorescence. The results showed that whereas primitive hematopoietic stem cells (PHSCs) are hierarchically ordered on the basis of quiescence, the most primitive of these, characterized by their Rh/Ho(dull) phenotype and their capacity for long-term hematopoietic reconstitution, are not dormant, but cycle slowly in normal steady-state bone marrow (BM). Cell cycle analysis showed that 30 +/- 7% of Rh/Ho(dull) PHSCs had cycled and incorporated BrdU following continuous administration over 1 week, whereas 60 +/- 14% and 89 +/- 3% of these cells were BrdU positive at 4 and 12 weeks, respectively. Linear regression analysis of these data showed that Rh/Ho(dull) PHSCs cycle with an average turnover time of 4.3 weeks (30 days), and a t1/2 (time to 50% cycled) of 2.75 weeks (19 days).

Effect of antiorthostatic hypokinetic/hypodynamia on urinary endothelin-1 and N-acetyl-beta-D-glucosaminidase excretion in rats

In an experimental model with rats in head-down suspension, plasma levels and urinary excretion of endothelin-1 (ET-1) and urinary excretion of N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30; NAG) were determined. Significant variations in time in the effective plasma ET-1 levels in the superior and inferior cava vessel blood of animals maintained for 6 days in hypogravity with respect to controls were observed. We not only found a transient increase in urinary NAG activity but also that the levels of U-ET-1 increased during head-down suspension. The simultaneous evaluation at urinary level of these two parameters could be an indication that there are different sites of renal parenchymal involvement or injury during antiorthostatic hypokinesis.

G-cell density in the antral mucosa: a feasibility study

In this work a new method for gastrin-secreting cell (G-cell) density measurement was employed in order to test the hypothesis that G-cell density of the antral mucosa can be estimated with an acceptable degree of error. The zone of antral mucosa where most G-cells are located was demarcated, its area was measured and the G-cells within this area were counted. The variation in the e error of the estimate according to normal distribution theory, and the size of the sampling expected to yield G-cell density values with a given error were assessed. Our data indicate that a very large surface of the G-cell zone should be explored in order to estimate G-cell density with an acceptable degree of error. G-cell density measurement appears not to be feasible on biopsy specimens or, for routine diagnosis, on gastrectomy specimens.

Possible involvement of neuropeptidergic sensory nerves in alopecia areata

Alopecia areata (AA) is a dermatosis involving the sudden occurrence of bald patches on the scalp. Although the aetiology is unknown, experimental data indicate that cutaneous microcirculation plays an important role. The skin is richly innervated by neuropeptidergic sensory nerves that help regulate microvascular circulation. This study shows a reduction of cutaneous levels of substance P and calcitonin gene-related peptide (CGRP) but not of vasoactive intestinal polypeptide in scalp biopsies from patients with AA. Laser-Doppler flowmetry was used to study microcirculation of the scalp. Results indicate that patients with AA have lower basal blood flow and greater vasodilatation following intradermal CGRP injection than control subjects. A vascular hyper-reactivity to vasodilatatory substances such as neuropeptides, probably because of the lack of these substances, is hypothesized.

Hyperpolarization of hepatocytes by 2,5-AM: implications for hepatic control of food intake

Because 2,5-anhydro-D-mannitol (2,5-AM) seems to stimulate feeding by acting on the liver and because the hepatic membrane potential has been suggested to play an important role in control of feeding ("potentiostatic" hypothesis), we investigated the effect of 2,5-AM on the membrane potential of liver cells with microelectrodes using a superfused liver slice technique. 2,5-AM (2.5 mM), which reduces intracellular ATP in rat liver, hyperpolarized the liver cell membrane in mouse and rat liver slices by 4-7 mV. This hyperpolarization was reversed by quinine (1 mM), an unspecific blocker of Ca2+-dependent K+ channels, and abolished by apamin (20 nM), a blocker of Ca2+-activated K+ channels with low conductance. Amiloride at 10(-3) M, but not at 10(-6) M, or a low-Na medium (26 mM) also eliminated the hyperpolarization. The K+ channel blockers cetiedil (50 microM), glibenclamide (30 microM), and Ba2+ (5 mM); flufenamic acid (100 microM), a blocker of nonselective cation channels; and ouabain (1 mM), an inhibitor of the Na+-K+-adenosinetriphosphatase, did not significantly influence the 2,5-AM-induced hyperpolarization. It is concluded that 2,5-AM hyperpolarizes the liver cell membrane by activating Ca2+-dependent K+ channels. This activation seems to be impaired when the Na+/H+ exchanger is inhibited by amiloride or a low-Na+ medium. The findings also imply that the hyperphagic effect of 2,5-AM observed in rats is not associated with a decrease in the hepatic membrane potential, as postulated by the potentiostatic hypothesis.

[Early care or quick transport? The effectiveness of preclinical treatment of emergency patients]

"Stay and play," especially in emergency patients with unstable vital functions, offers definite advantages compared to "scoop and run" policies. Typical medical and tactical aspects can be identified to judge the amount of diagnostic and therapeutic measures necessary at the site and during transport. Scoop and run seems to be appropriate only rarely in a area with an emergency medical system in the German style.

Piggy-back versus conventional technique in liver transplantation: report of a randomized trial

Liver transplantation with preservation of the recipient vena cava (the "piggy-back" technique) has been proposed as an alternative to the traditional method. We performed a randomized study on 39 cirrhotic patients, 20 who underwent the piggy-back technique (group 1) and 19 the traditional method using venovenous bypass (group 2) to evaluate the feasibility and true advantages of the piggy-back technique compared to the traditional method. Two patients were switched to the conventional technique due to the presence of a caudate lobe embracing the vena cava in one patient and a caval lesion in the other. Statistically significant differences between the two groups were only found for the warm ischemia time (48.5 +/- 13 min for piggy-back vs 60 +/- 12 min for the conventional method) and for renal failure (zero cases in group 1 vs four cases in group 2). We therefore believe that liver transplantation with the piggy-back technique can easily be performed in almost all cases, and that only a few, specific situations, such as a very enlarged caudate lobe, do not justify its routine use.

Motor recovery after stroke. Morphological and functional brain alterations

The aim of this study was to evaluate the relationships of morphological and CBF patterns with both the severity and the evolution of the motor deficit in the late phase of stroke and, in particular, to identify morphological and/or functional brain alterations associated with a persistent severe motor deficit or a poor, delayed motor recovery. We analysed CT/MRI and single photon emission tomography (SPET) findings from 37 patients studied in the chronic phase of stroke (mean duration +/- SD = 3.6 +/- 1.6 months), whom we were able to follow clinically for a period of 3 months. The eventual degree of motor recovery correlated significantly (negatively) with the time since stroke at entry, but not with the severity of neurological impairment at entry. The volume, side and location (cortical or subcortical) of the infarct did not correlate with either the severity or the evolution of the motor deficit. Patients with a CT/MRI lesion of the parietal lobe (n = 8) showed a more severe motor deficit than those with other cortical locations. The severity of the motor deficit correlated significantly (negatively) with CBF values in the supplementary motor area (SMA) and parietal areas of the damaged hemisphere, and in the contralateral undamaged primary motor cortex. The degree of motor improvement correlated significantly (positively) with CBF values in the contralateral undamaged thalamus, lentiform and caudate nuclei, and premotor cortex. In the late phase of stroke, the severity of the motor deficit may be positively associated with the functional impairment of associative parietal and frontal areas of the damaged hemisphere. The functional impairment of the basal ganglia-frontal network in the undamaged hemisphere seems to be related to a poor, delayed motor recovery.