Lymph Node Involvement and Surgical Approach in Parathyroid Cancer

Background  

The best surgical approach to parathyroid cancer is disputed. Recommendations vary and are built on incoherent evidence. High rates of recurrence and death require an in-depth review of underlying findings.     

Spectral and Time-Domain Analyses of Heart-Rate Variability During Head-Upright Tilt-Table Testing in Children with Neurally Mediated Syncope

Neurocardiac syncope (NS) is a common cause of syncope in children. The mechanism, though related to abnormalities in autonomic function, has not been fully elucidated, particularly in pediatric patients. This study assessed the heart-rate variability (HRV) response to head-upright tilt-table test (HUT) in children with NS and normal volunteers. Spectral and time-domain analysis of HRV was used to assess changes in autonomic function in 27 children (9 male, mean age 12.3 ± 1.6 years) with a history of at least one episode of syncope and positive passive HUT and 27 age-matched normal volunteers with negative passive HUT before and during postural tilt and to attempt to relate such changes to specific types of hemodynamic response to tilt. Frequency-domain measurements of the high-(HF) and low-(LF) frequency bands and the ratio LF/HF were derived from Holter recordings and computed by fast Fourier analysis for 5-min intervals. Time-domain measurements of the SDNN, SDNNI, SDANN, RMSSD, and triangular index were derived from 24-h Holter recordings. There were no significant differences between clinical characteristics, time-domain, and basal frequency domain parameters of the groups. Mean values of LF and LF/HF ratio was increased and HF was decreased significantly in response to tilt in both patient and control groups. Mean values of LF and LF/HF ratio were higher and HF was lower compared to controls immediately after tilt. LF and LF/HF ratio showed a statistically significant decrease and a significant increase in HF during syncope in patients. The three subgroups of patients had similar patterns of changes in autonomic activity. The results of this study show that although the basal autonomic function was similar to that of the control group, patients with NS have a different pattern of response to the HUT. In our study, patients with NS demonstrated an exaggerated response to the HUT. This exaggerated response may be the factor that activates the pathological reflexes of NS. The pathological mechanism leading to NS appears to be independent of the specific type of hemodynamic response to HUT.     

Crystal structure of a novel phospholipase A2 from Naja naja sagittifera with a strong anticoagulant activity

This is the first PLA₂ crystal structure from group I that shows a strong anticoagulant property. The monomeric PLA₂ was purified from the venom of Naja naja sagittifera (Indian cobra). Its amino acid sequence has been determined using cDNA technique. The amino acid sequence of sPLA₂ contains three positively charged and two negatively charged residues in the segment 54–71 (numbering scheme of sPLA₂) thus giving this region an overall cationic amphiphilic surface. This suggested the presence of an anticoagulant activity in sPLA₂. The enzyme was crystallized using hanging drop vapour diffusion method in the presence of calcium chloride. The crystals belong to space group P4₁ with cell dimensions of a=b=42.0 Å, c=65.9 Å. The X-ray crystal structure was determined at 1.8 Å resolution using molecular replacement method and refined to an R value of 0.179 for 10,023 reflections. The overall scaffolding of sPLA₂ is essentially similar to those observed for other group I PLA₂s. However, the conformations of various surface loops were found to be significantly different. The most significant observation pertains to the anticoagulant loop in which both the acidic residues are engaged in intramolecular interactions whereas all the three basic residues are free to interact with other molecules. This makes the sPLA₂ a potentially strong anticoagulating molecule.     

Bromocriptine-induced cerebrospinal fluid fistula in patients with macroprolactinomas: Report of three cases and a review of the literature

Bromocriptine therapy for macroprolactinoma induced cerebrospinal fluid (CSF) rhinorrhea in three patients. The tumor had extended well beyond the sella turcica and caused bony erosion in all the cases. All three patients responded to bromocriptine therapy rapidly. CSF fistula occurred concomitantly with the reduction of tumor size and caused meningitis in two of the patients. Withdrawal of bromocriptine resulted in cessation of the leakage. One of the patients underwent transsphenoidal repair. Two patients refused surgery. This potentially lethal complication encountered in these three cases demonstrates the need for close supervision of macro-prolactinoma patients with skull base erosion placed under bromocriptine therapy.     

Protective effect of dexpanthenol on bleomycin-induced pulmonary fibrosis in rats

Despite extensive studies, there is no effective treatment currently available other than pirfenidone for idiopathic pulmonary fibrosis. A protective effect of pantothenic acid and its derivatives on cell damage produced by oxygen radicals has been reported, but it has not been tested in bleomycin (BLM)--induced pulmonary fibrosis in rats. Therefore, we aimed to investigate the preventive effect of dexpanthenol (Dxp) on pulmonary fibrosis. Thirty-two rats were assigned to four groups as follows: (1) control group, (2) dexpanthenol (Dxp) group; 500 mg/kg Dxp continued intraperitoneally for 14 days, (3) bleomycin (BLM) group; a single intratracheal injection of BLM (2.5 mg/kg body weight in 0.25-ml phosphate buffered saline), and (4) BLM + Dxp-treated group; 500 mg/kg Dxp was administered 1 h before the intratracheal BLM injection and continued for 14 days i.p. The histopathological grades of lung inflammation and collagen deposition, tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and myeloperoxidase (MPO) were measured. BLM provoked inflammation and collagen deposition (p?<?0.0001), with a marked increase in myeloperoxidase (MPO) activity resembling increased inflammatory activity (p?<?0.0001), which was prevented by Dxp (p?<?0.0001, p?=?0.02). BLM reduced tissue activities of SOD, GPx, and CAT compared to controls (p?=?0.01, 0.03, 0.009). MDA was increased with BLM (p?=?0.003). SOD (p?=?0.001) and MDA (p?=?0.016) levels were improved in group 4. The CAT levels in the BLM + Dxp group were close to those in the control group (p?>?0.05). We showed that Dxp significantly prevents BLM-induced lung fibrosis in rats. Further studies are required to evaluate the role of Dxp in the treatment of lung fibrosis.     

Androgen induced acceleration of functional recovery after rat sciatic nerve injury

PURPOSE: Testosterone (T) treatment accelerates recovery from facial paralysis after facial nerve crush in hamsters. In this study, we extended those studies to another injury model and asked the following question: Will T treatment accelerate recovery from lower limb paralysis following sciatic nerve crush in the rat? METHODS: Castrated adult male rats received a right side sciatic nerve crush at the level of the sciatic notch, with the left side serving as control. Half the animals received a subcutaneous implant of a propionated form of T (TP), the others were sham-implanted. Weekly testing using the Sciatic Functional Index (SFI), a quantitative measure of locomotion, was done for 7 weeks postoperative (wpo). RESULTS: Between 3 and 5 weeks post-op, the average SFI score of the TP-treated group was higher than controls. This difference was significant at 4 wpo, indicating an accelerated degree of functional recovery. At these timepoints, the differences were attributable to the footprint or paw length and associated with calf muscle reinnervation rather than the toespreading component associated with intrinsic foot muscle rein-nervation. Beyond 5 wpo, there were no differences in the SFI scores. CONCLUSION: The results indicate that, as with facial nerve regeneration in the hamster, testosterone accelerates functional recovery from hind limb paralysis following sciatic nerve injury in the rat. While the responses of spinal motoneurons to injury can differ from those of cranial motoneurons, in this case it appears that they share a similar response to the trophic actions of androgen. This is important in the context of designing therapeutic strategies for dealing with direct trauma to motoneurons resulting from both peripheral and central nervous system trauma, such as spinal cord injury.