Ionic Channels in Sea Urchin Sperm Physiology

In sea urchin sperm, ionic fluxes modulate the activation of respiration and motility and the acrosome reaction, a prerequisite for egg fertilization. Ionic channels are present in the plasma membrane of these cells, and there is good evidence indicating that they are deeply involved in these processes.

Cerebral mucormycosis in two cases of acquired immunodeficiency syndrome

We describe two patients with isolated cerebral mucormycosis and acquired immunodeficiency syndrome (AIDS). Their clinical course was rapid and fatal; early diagnosis and treatment with amphotericin B did not prevent a fatal outcome in both cases. Isolated cerebral mucormycosis has not (to our knowledge) been reported previously in patients with AIDS. Mucormycosis should be included in the differential diagnosis of central nervous system infections in intravenous drug abusers with AIDS. A brain biopsy is needed for the diagnosis of mucormycosis.

Single-channel activity in sea urchin sperm revealed by the patch-clamp technique

Ionic fluxes are deeply involved in the response of spermatozoa to the egg. Using the patch-clamp technique, we show for the first time single ion channel activity in sea urchin spermatozoa and spermatozoa heads. Due to their small size gigaseals were obtained in suspended cells by applying suction through the pipette. The rate of gigaseal formation was very low and improved to 6% (n = 1145) when flagella were detached from sperm. Current-voltage curves created from single-channel events showed conductances of approx. 65 and 170 pS, suggesting the presence of two types of channels. At least one appears to be a K+ channel.

Brucellar meningitis

Neurobrucellosis develops in less than 5% of cases of systemic brucellosis; however, most patients with neurobrucellosis have meningeal involvement. Seven new cases of brucellar meningitis and 17 cases from the Spanish- and English-language medical literature are analyzed in terms of epidemiologic data, clinical manifestations, laboratory results for cerebrospinal fluid and serum, treatment, and course of the disease. Brucellar meningitis mimics other neurologic and non-neurologic conditions, and its diagnosis is only suggested in the presence of adequate epidemiologic information. Isolation of Brucella from the cerebrospinal fluid is uncommon. Treatment is accomplished with the combination of tetracycline or doxycycline and streptomycin, rifampin, or both. Mean length of therapy in the seven new cases was 8.5 months. Brucellar meningitis has a better prognosis than other forms of chronic meningitis, and mortality is low for reasons that are not clear; however, the incidence of minor sequelae is high.

Behaviour of the contact phase of blood coagulation in the adult respiratory distress syndrome (ARDS)

In order to assess the role of the kallikrein-kinin (K-K) system in the pathogenesis of the adult respiratory distress syndrome (ARDS) we have prospectively determined coagulation contact phase, blood gas and hemodynamic parameters in patients with ARDS at 0, 36 and 72 h from diagnosis. Compared to normal values, significantly lower mean levels of factor XII (71.4 +/- 9.8%, p less than 0.0005), prekallikrein (PPK) (52 +/- 5.7%, p less than 0.0005), high molecular weight kininogen (HMWK) (73 +/- 2%, p less than 0.0005) and alpha 2-macroglobulin (alpha 2-M) (51 +/- 7.1%, p less than 0.0005) were found in ARDS patients. The functional kallikrein inhibitory activity (KKI) and C1-esterase inhibitor antigenic (CIINH) were significantly higher in these patients (113.2 +/- 5, p less than 0.005 and 124.7 +/- 7.6, p less than 0.0005 respectively) compared with normal values during the entire study period. The KKI/CIINH ratio decreased significantly in our ARDS patients at 0, 36 and 72 h (p less than 0.025; p less than 0.05 and p less than 0.005 respectively). We found a significant correlation between PPK levels and oxygenation index (r = 0.69, p less than 0.001), PPK and the static thoracic compliance values (r = 0.64, p less than 0.001). There was also a significant correlation between PPK levels and Qs/Qt (r = -0.89, p less than 0.001). ARDS patients that survived presented a stability in the PPK values in successive tests. Nevertheless non-survivors showed a progressive decrease in PPK levels during the follow-up period.(ABSTRACT TRUNCATED AT 250 WORDS)

Mannose incorporation and lectin recognition of pronase-sensitive components in Micrococcus lysodeikticus (M. luteus) membranes

Isolated cytoplasmic membranes from Micrococcus lysodeikticus were able to incorporate [14C]mannose from GDP-[14C]mannose. Labelled mannose remained in the membrane fraction after its repeated washing and lipid extraction. Sodium dodecyl sulfate gel electrophoresis in 12% acrylamide showed a set of bands with molecular weights ranging from 230 000 to 19 000 which stained for protein and carbohydrate, and incorporated [14C]mannose. Some of these bands reacted with different lectins (concanavalin A, wheat germ agglutinin and ricin). Furthermore, the mannose was incorporated via a glycosylation pathway similar to that followed in eukaryotic system as shown by the preliminary identification of a lipid intermediate transferring the sugar to proteins and by the differential sensitivity to bacitracin and tunicamycin. These complex membrane components were sensitive to digestion with pronase. All the results presented suggest their glycoprotein nature.

Epilepsy and brain tumors in infancy and adolescence

Four boys and four girls with brain tumors who were admitted to our department in the last 8 years are herein described. They presented with epileptic fits, which began before the age of 14 years, with neither intracranial hypertension nor localizing signs during the first 6 months of the illness. The length of time between the first fit and the diagnosis of a tumor ranged from 2 months to 11 years (median of 3 years), during which period all patients but one received anticonvulsant therapy. The nontreated patient was under psychiatric treatment for 1 year. The electroencephalographic evolution was disconcerting, showing asymmetry of the recording with association of slow polymorphic waves and acute irregular waves, suggesting encephalitis. The neuroradiological diagnosis was made by cerebral arteriography in one patient and in the others by angiography and CT scans (which revealed hypodense cerebral areas in five cases and hyperdense areas in the other two). The histology of the tumor was that of a grade I astrocytoma in six cases; a grade III oligondendroglioma in one case, and a meningioma in the other. All patients underwent surgical treatment. Four also received radiation therapy, two for a partially excised astrocytoma and one each for an oligodendroglioma and a meningioma. Postoperatively, all patients were put on anticonvulsant drug therapy. There were no mortalities. To date, only one astrocytoma has recurred. The sequellae observed were hemiparesis in one case and marked psychomotor deficit in another. These two patients also still have epileptic fits. The others are all psychologically and neurologically normal, and two are now off antiepileptic drugs.

Evaluation of aztreonam in the treatment of severe bacterial infections

We investigated the clinical efficacy and safety of aztreonam in the treatment of 50 episodes of infection in 46 adult patients. The clinical condition of patients at the beginning of treatment was critical or poor in 28 of the episodes of infection. Episodes treated were 39 urinary tract infections (12 of them with concomitant bacteremia), 2 soft tissue infections, 8 patients with osteomyelitis (1 with concomitant bacteremia), and one episode of pneumonia. Significant isolated microorganisms were aerobic or facultative gram-negative rods and were responsible for the following episodes of infection (number of episodes): members of the family Enterobacteriaceae (49), Pseudomonas aeruginosa (5), and Haemophilus influenzae (1). The overall rate of clinical response to aztreonam was 94% of the treated episodes. Colonization or superinfection or both occurred in 29 episodes, but only 8 episodes required antimicrobial therapy. Aztreonam seems to be an effective single agent therapy for many bacterial infections. Colonization and superinfection by Candida sp., Streptococcus faecalis or Staphylococcus aureus must be monitored.

Klebsiella bacteremia: an analysis of 100 episodes

During a five-year period, 204 patients had klebsiella bacteremia at this institution; these cases constituted 6.6% of the total episodes of bacteremia. The incidence was 2.3 cases per 1,000 admitted patients. A random group of 100 cases was chosen for analysis in the present study. The disease was community acquired in 23%, nosocomially acquired in 77%, unimicrobial in 88%, or part of a polymicrobial bacteremia in 12% of episodes. Three-quarters of the episodes were caused by Klebsiella pneumoniae and the remaining one-quarter, by Klebsiella oxytoca. Portals of entry, in decreasing order of frequency, were urinary, respiratory, and biliary tracts. Twenty-four percent of the Klebsiella isolates were resistant to gentamicin. The most frequent clinical finding (in 96% of the cases) was fever. Shock occurred in 22% and pyogenic metastatic foci, in 5% of the patients. None of the patients had evidence of disseminated intravascular coagulation. Overall mortality was 25%, and factors associated with poor prognosis were inadequacy of antimicrobial chemotherapy, septic shock, type of underlying disease, and clinical condition of the patients.

Evaluation of lamoxactam in the treatment of severe bacterial infections

We investigated the clinical efficiency and safety of lamoxactam for treatment of 28 episodes of infection in 26 adult patients (15 males and 11 females) whose ages ranged from 17 to 83 years (mean 48.7). 4 patients had 'ultimately fatal diseases' and the remaining 22 had 'nonfatal diseases'. The clinical condition at the beginning of treatment was 'critical' or 'poor' in 15 cases. Episodes of infection treated were: 14 intraabdominal, 9 bacteremia, 5 nephro-urinary, 3 osteomyelitis, and a miscellaneous group including pneumonia, soft tissue, parameningeal focus and infected V-P shunt. A total of 34 microorganisms were responsible for 25 episodes of infection. 15 and 10 episodes were mono- and polymicrobial, respectively. Isolated microorganisms included 13 aerobic facultative gram-negative bacillus, 5 facultative gram-positive cocci, and 16 anaerobes. Total dosage of lamoxactam administered by patient ranged from 24 to 234 g (mean 57.6 g), and mean duration of therapy was 15.2 days (range 8-42 days). The overall rate of clinical response to lamoxactam was excellent, amounting to 84% of episodes and 91% of patients. Local and general tolerance was good, and lamoxactam had to be discontinued only once during therapy due to an episode of neutropenia. Enterococcal colonization (5 of 26 patients, 19%) and superinfections (3 of 26 cases, 11.5%) were undesirably frequent in our patients. Lamoxactam seems to be an effective and safe single-agent therapy for many bacterial infections. The possibility of enterococcal colonization and superinfections should be monitored, specially in patients with urinary or intraabdominal infections.

[Acute Q fever: study of 23 patients (author's transl)]

Twenty-three patients with Q fever who were diagnosed over a 3 year period are described. The majority came from the Madrid urban area and less than half had epidemiological antecedents. Nine patients presented with pulmonary infiltrations, 12 with suppressed fever and in 2 criteria for fever of unknown origin were met. The majority had clinical or analytic data of hepatic disease and liver biopsy practiced in 4 patients showed granulomas. Diagnosis was established through the increment of seric antibodies against antigens of phase II C. burnetii, detected by complement fixation test. Acute Q fever is not a rare disease in our environment and must be taken into account when a differential diagnosis is looked for in processes such as fever of short evolution, fever of unknown origin, pneumoniae and granulomatous hepatitis.