Compatibility study between acetylcysteine and some commonly used tablet excipients.

Differential scanning calorimetry (DSC), Fourier transform infra-red spectroscopy (FT-IR), HPLC and TLC were used to investigate the interactions between the mucolytic drug acetylcysteine and a number of commonly used tablet and capsule excipients. Acetylcysteine was found to be compatible with microcrystalline cellulose (Avicel PH 101), sodium carboxymethylcellulose, amorphous silicon dioxide (Aerosil), PVP, cross-linked PVP (Polyplasdone XL), corn starch, saccharose and magnesium stearate. Acetylcysteine thermal stability (onset degradation temperature) was decreased in mixtures with corn starch, magnesium stearate, saccharose and lactose. Interactions of acetylcysteine with lactose, PEG 4000 and 6000, glycine, adipic acid and saccharin sodium were found using DSC and studied in detail with FT-IR, HPLC and TLC. The results suggest that acetylcysteine in mixtures with PEG 4000, glycine or saccharin sodium is degraded during storage at conditions of high temperature and humidity.     

Characterization of antisera against bovine prolactin for in vivo studies on prolactin function in the rat.

The IgG fraction of rabbit antisera to bovine prolactin (PRL), intended for in vivo studies on the role of PRL in the rat, was prepared and characterized in vitro and in vivo. The antibodies showed a strong reaction with bovine PRL in double diffusion, immunoelectrophoresis, radioimmunoassay and passive haemagglutination using bovine PRL-coated erythrocytes. In indirect immunofluorescence on paraffin sections of bovine pituitary glands the antibodies could be used for the detection of PRL-producing cells. Cross-reaction with rat PRL was observed in passive haemagglutination with rat PRL-coated erythrocytes and in indirect immunofluorescence on rat pituitary gland, but not in any of the other test systems. The ability of the antibodies to neutralize homologous, i.e. bovine, PRL was tested in lactating rats depleted of endogenous PRL by bromergocriptin treatment. The impaired lactation performance of such animals can be restored by substitution with bovine PRL. If the bovine PRL used for substitution was complexed with anti-bovine PRL-IgG, it lost its biological activity. On the other hand, injections of even high amounts of the antibodies into lactating rats failed to reveal any effect on lactation. It is concluded that either the antibodies do not cross-react with circulating rat PRL in contrast to pituitary PRL (preprolactin?) or that the cross-reacting antibody-populations(s) lack(s) the ability to neutralize the biological function of rat PRL.     

Comparison of Western blot (immunoblot) based on recombinant-derived p41 with conventional tests for serodiagnosis of human immunodeficiency virus infections.

To evaluate the performance of a serological test for human immunodeficiency virus type 1 (HIV-1) infections based on the use of a recombinant envelope gene-derived protein as the antigen, we caused expression of a 1.4-kilobase fragment of HIV.DNA that codes for the complete gp41 transmembrane protein in an Escherichia coli expression vector and used Western blots (WB; immunoblots) prepared with recombinant material (pEX-41) to detect antibodies to HIV-1. This test detected all 339 sera which were positive by a combination of conventional serodiagnostic assays and produced no false-positive results with 311 negative samples. Also no false-positive results were obtained with 20 sera from systemic lupus erythematosus patients which had high titers of cross-reactive autoantibodies. In six cases, the pEX-41 WB proved to be more sensitive than individual assays applied on their own, and in five cases it was even more sensitive than a combination of conventional assays. We tested 221 sera in both our pEX-41 WB and a commercially available recombinant enzyme immunoassay (EIA [Abbott]). The results were identical in 188 cases. A total of 27 sera containing antibodies to gp41 as demonstrated in the pEX-41 WB, as well as the Abbott recombinant EIA, had no antibodies to the recombinant core antigen as measured in the Abbott EIA. However, 25 of these sera did stain the 24-kilodalton band on a WB with purified virus. Six sera that were positive in all of the conventional confirmatory assays and reacted strongly with the pEX-41 WB did not recognize the surface antigen used in the Abbott recombinant EIA. We conclude that the use of WB prepared with recombinant-derived p41 offers a very sensitive and specific method to detect antibodies to HIV.     

Immunological dissection of rat pregnancy: study of the mode of action of antisera to luteinizing hormone.

The sensitivity of rat pregnancy to luteinizing hormone (LH) depletion on days 7--12 (day 1 = day of insemination) was investigated by intraperitoneal administration of a single injection of various doses of an anti-bovine LH rabbit serum on the day in question. Day 11 was found to be the most susceptible time for this kind of intervention. The fate of the anti-LH antibodies in the recipients was followed in the serum and in various organs of the treated animals. Serological analysis revealed persistence of free antibodies to LH in the serum as late as 48 hr after injection. Immunofluorescence studies showed immune complex deposition in the kidney glomerula.     

Complications after laryngeal surgery: videofluoroscopic evaluation of 120 patients

AIM: Videofluoroscopic assessment of the spectrum and incidence of swallowing complications after state-of-the-art laryngeal cancer surgery. MATERIALS AND METHODS: We retrospectively studied videofluoroscopic examinations of 120 patients (94 men, 26 women; mean age, 58 years) with suspected complications after laryngeal resection (partial laryngectomy, 65; total laryngectomy, 55). Swallowing function (i.e., oral bolus control, laryngeal elevation and closure, presence of pharyngeal residue, aspiration) and structural abnormalities such as strictures, fistulas and tumour recurrence were assessed by videofluoroscopy. RESULTS: Abnormalities were found in 110 patients, including strictures in nine, fistulas in six and mass lesions in 13 patients. Aspiration was found in 63 patients overall (partial laryngectomy, 61/65; total laryngectomy, 2/55), occurring before swallowing in five, during swallowing in 34, after swallowing in nine and at more than one phase in 15 patients. Pharyngeal paresis was detected in three and pharyngeal weakness in 19 patients. Pharyngo-oesophageal sphincter dysfunction was observed in 10 cases. CONCLUSION: Aspiration is a very common complication after partial laryngeal resection. It is mainly caused by incomplete laryngeal closure, sphincter dysfunction or pharyngeal pooling. Videofluoroscopy is the only radiological technique able to identify both disordered swallowing function and structural changes after laryngeal resection. Detection of these complications is crucial for appropriate further therapy.Kreuzer, S. H. (2000). Clinical Radiology55, 775-781.     

Brain temperature regulation in poor-grade subarachnoid hemorrhage patients – A multimodal neuromonitoring study

Elevated body temperature (T_core) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (T_brain) is usually higher than T_core. However, the implication of this difference (T_delta) remains unclear. We aimed to study factors associated with higher T_delta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of T_core, T_brain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. T_brain was tightly correlated with T_core (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (T_delta +0.18°C, IQR −0.01 – 0.37°C). A higher T_delta was associated with better metabolic state, indicated by lower CMD-glutamate (p = 0.003) and CMD-lactate (p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, T_delta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher T_delta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that T_brain is associated with brain metabolic activity and exceeds T_core when mitochondrial function is preserved. Further studies are needed to understand how T_delta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH.     

Ein seltenes genitales Ulkus

We report the case of a young girl who presented with acute severe pain from a genital ulceration. The diagnosis of ulcus vulvae acutum or Lipschütz??s acute ulcer of the vulva, a self-healing, acute genital ulceration of unknown origin but characteristic clinical picture was established. The patient recovered fully with symptomatic treatment, mainly appropriate analgetics within 14 days. A review of the scarce literature is discussed and the importance of non-invasive diagnostic procedures is stressed.