Combined sialendoscopic/mini-preauricular microscopic approach for large proximal parotid sialolithiasis

ObjectiveTo describe and evaluate a combined approach for sialendoscopic stone localization with microscopic mini-preauricular incision external stone extraction as a gland-sparing minimally invasive surgical management in cases of large proximal duct or intraparenchymal parotid gland sialolithiasis.MethodsA retrospective chart review of a single primary surgeon's patient series of 21 cases operated in a 5-year period in a tertiary care university and private practice hospitals.ResultsStudy included 16 males and five females, with age range 12–68 years (mean 40.9 ± 14.5). Nineteen out of the 21 patients had their stones completely removed (90.5%), with two not completing the procedure due to inability of intraoperative endoscopic stone visualization. In total 25 stones were extracted with six patients having two stones. Longest diameter of single (or first) stone was 5–16 mm (mean 9.1 ± 2.9) and second was 3–5 mm (mean, 3.9 ± 0.6). Endoscopic findings showed 14/25 stones in the proximal main parotid duct and 11/25 in one of its secondary parenchymal branches. Stents were used in 4/19 cases (21.1%). No major complications occurred. Minor complications included two postoperative conservatively managed seromas. All 19 cases had completely intact facial nerve function, good parotid salivary flow and acceptable esthetic result after median follow-up period of 26 months (range 6–62).ConclusionThe combined sialendoscopic/microscopic mini-preauricular approach is a highly effective and safe gland-preserving method for large proximal parotid sialolithiasis management with a main limitation being inability to visualize the stone endoscopically.     

Dietary sucrose affects plasma HDL cholesterol concentration in young men

Fourteen young male volunteers measured their habitual dietary intake for 2 weeks, then were told to increase their dietary sucrose while decreasing their other carbohydrates for 2 weeks and finally told to revert to their habitual diet while continuing to record their intake. Measurement of plasma constituents revealed a significant fall in HDL-cholesterol concentration after the period on the high sucrose diet, and a return to the higher concentrations after resumption of the habitual diet. Twenty-six young men whose habitual diet contained more than an average quantity of sucrose followed a similar regime, except that they were told to reduce their sucrose for 2 weeks and to compensate by increasing the intake of other carbohydrates. In the event, unlike the volunteers in the first experiment, they were found not to have made the compensatory change when lowering their sucrose intake. Measurement of their plasma constituents showed that the reduction in dietary sucrose resulted in a significant fall in the mean concentration of triglycerides. There was no significant change in the mean concentration of HDL cholesterol, although there was an increase in the concentration in 11 of the 26 subjects.     

Plasma GLP-2 Levels and Intestinal Markers in the Juvenile Pig During Intestinal Adaptation: Effects of Different Diet Regimens

Adaptation of the residual small bowel following resection is dependent on luminal and humoral factors. We aimed to establish if circulating levels of glucagon-like peptide (GLP-2) change under different dietary regimens following resection and to determine if there is a relationship between plasma GLP-2 levels and markers of intestinal adaptation. Four-week-old piglets underwent a 75% proximal small bowel resection (n = 31) or transection (n = 14). Postoperatively they received either pig chow (n = 14), nonpolymeric (elemental) infant formula (n = 7), or polymeric infant formula alone (n = 8) or supplemented either with fiber (n = 6) or with bovine colostrum protein concentrate (CPC; n = 10) for 8 weeks until sacrifice. Plasma GLP-2 levels were measured at weeks 0, 2, 4, and 8 postoperatively. In addition, end-stage parameters were studied at week 8 including weight gain, ileal villus height, crypt depth, and disaccharidase levels. Plasma GLP-2 levels were higher in resected animals compared to transected animals fed the same diet. Plasma GLP-2 levels were significantly increased in the colostrum protein isolate-supplemented animals following resection compared to all other diet groups. The increase in plasma GLP-2 (pM) was greatest in the first 2 weeks postresection (week 0, 15.5; week 2, 30.9), followed by a plateau at weeks 2 to 4 and a decrease in GLP-2 levels from week 4 to week 8. At week 8, no relationships were found between the plasma GLP-2 levels and the measurements of weight gain, villus height, lactase, sucrase, maltase, crypt depth, or villus/crypt ratio. Plasma GLP-2 levels increase in the first weeks following massive small intestinal resection. The increase in plasma GLP-2 levels was enhanced by supplementation of the diet with CPC. The changes in GLP-2 levels observed in this study may suggest that GLP-2 plays a role in the adaptive response in the intestine following resection in this preclinical model.     

Changes in parietal cell structure and function in HIV disease

The mechanisms underlying acid secretory failure in patients with HIV disease are unknown. We evaluated, in a series of preliminary studies, changes associated with parietal cell structure and function in early and late HIV disease, in an attempt to elucidate possible underlying mechanisms. Gastric acid and intrinsic factor secretion, vitamin B₁₂ absorption, and light and electron microscopic evaluation of gastric mucosa were evaluated in patients with early and late HIV infection (AIDS) and compared to non-HIV-infected controls. Immunolocalization of HIV-related antigens in gastric mucosa was also examined. Fasting gastric juice pH and intrinsic factor (IF) concentration in AIDS and HIV infected subjects were significantly different from controls (P=0.012 andP=0.025, respectively for pH, and 0.029 and 0.035 for IF; ANOVA LSD test). By contrast, maximal acid output (MAO) was significantly lower in AIDS, but not HIV-infected subjects (P=0.043 andP=0.322, respectively). Similarly, Schilling test phases 1 and 2 results were significantly lower in AIDS, but not HIV-infected subjects. Varying degrees of vacuolar degeneration of parietal cells were seen on light microscopy. On electron microscopy (EM), tubulovesicles were reduced and intracellular canaliculi dilated with striking loss of microvilli. Immunofluorescent staining with antibodies to gp120, gp41, p24, and p17 demonstrated positive punctate signals in the cytoplasm of gastric glands, which includes parietal cells. Immunogold EM with anti-gp120, localized predominantly to the microvilli of intracellular canaliculi in parietal cells. Abnormal secretory function of parietal cells occurs early in HIV disease, affects acid as well as intrinsic factor secretion, and is associated with morphological changes in the acid secretory apparatus.     

The use of protamine after radiofrequency catheter ablation: A pilot study

Objective Evaluate the effect of administering intravenous protamine immediately post-radiofrequency catheter ablation (RFCA) on thrombotic and bleeding complications in heparinized patients. Methods Heparinized patients that had RFCA for atrial or ventricular arrhythmias at our institution between January 2001 and March 2006 and had a complete data set were included in this cohort evaluation. Patients receiving at least one dose of protamine within 15 min of RFCA were deemed the prophylactic group while those not receiving protamine within 15 min were the control group. Thrombotic (cerebrovascular event, transient ischemic attack, pulmonary embolism, deep vein thrombosis, or myocardial infarction) and bleeding events (blood loss requiring transfusion, hematoma requiring intervention, or intracranial hemorrhage) were compared between groups. Results Overall, 158 patients (74% male, 55 ± 13.5) met inclusion criteria. Of these, 73.4% received prophylactic protamine (average dose = 39 mg ± 17). Only one patient (0.9%) in the prophylactic protamine group and zero patients in the control group experienced a thrombotic event (p > 0.99). Only two patients (1.7%) in the protamine group (n = 2 blood transfusions) and zero patients in the control group experienced bleeding events (p = 0.839). Conclusions Administering prophylactic intravenous protamine to allow for quicker catheter removal following RFCA in heparinized patients did not markedly impact thrombotic or bleeding complication rates in our population. The perceived benefit in our institution to protamine administration in this population is a reduction in postoperative patient immobilization and discomfort, reduced PACU nursing care, and earlier time to discharge. Given the low rate of thrombotic and bleeding events, a study of several thousand patients would be needed to fully evaluate the impact on these events.     

Is matrix metalloproteinase required in postnatal testicular tubules for germ cell maturation?

Background/AimCryptorchidism may cause infertility by failed transformation of neonatal gonocytes into adult dark spermatogonia, the putative stem cells for spermatogenesis. Gonocytes migrate centrifugally to the tubular basement membrane to become adult dark spermatogonia. Regulation of this transformation remains unknown. We aimed to investigate neonatal rodent testis matrix metalloproteinase (MMP) production to see whether MMPs loosen extracellular matrix between Sertoli cells to facilitate gonocyte movement.MethodsSprague-Dawley rat testes (n = 4-6 per group) were collected at embryonic day 19 (E19) and postnatal (P) days P0 to 10 for immunohistochemistry. Immunofluorescent confocal images were captured for presence of membrane type 1 MMP (MT1-MMP), matrix metalloproteinase 2 (MMP2), tissue inhibitor of metalloproteinase 2 (TIMP2), mouse VASA homologue, anti-Müllerian hormone, and androgen receptor in tissue sections. Testicular proteins were analyzed by immunoblotting.ResultsMembrane type 1 MMP was strongly present in gonocytes at E19 then decreased, whereas it increased in testicular somatic cells from P0 to P10. Testicular protein levels of MT1-MMP, MMP2, and androgen receptor were constant from E19 to P10. Anti-Müllerian hormone protein sharply decreased after P2, whereas TIMP2 gradually increased from E19 to P10. Gonocytes migrated to basement membrane at P2 to P6.ConclusionMembrane type 1 MMP, MMP2, and TIMP2 were present in testis from E19 to P10 during gonocyte migration and transformation into spermatogenic stem cells. Increased knowledge about germ cell development may aid efforts to improve fertility in cryptorchidism.