Risk Factors for Readmission After Parathyroidectomy for Renal Hyperparathyroidism.

BACKGROUND: Patients with renal hyperparathyroidism (RHPT) are susceptible to major electrolyte fluctuations following parathyroidectomy, which may predispose them to early readmission. The purpose of this study is to evaluate risk factors for readmission in patients undergoing parathyroidectomy for RHPT. METHODS: Patients with renal failure who underwent parathyroidectomy were abstracted from the California Office of Statewide Health Planning and Development (1999-2012). Multivariable logistic regression was used to identify risk factors for readmission within 30 days of discharge. RESULTS: The cohort included 4411 patients, of whom 17% were readmitted. Procedures included subtotal parathyroidectomy (74% of cases) and total parathyroidectomy with autotransplantation (26%). Median time to readmission was 9 days (interquartile range 4-16 days). Electrolyte disturbances including hypocalcemia were present in 36% of readmissions and were the most common cause for readmission. Independent risk factors for readmission included Black race [odds ratio (OR) 1.26, 95% confidence interval (CI) 1.00-1.57], Hispanic race (OR 1.38, 95% CI 1.12-1.71), disposition with home health (OR 1.94, 95% CI 1.35-2.77), disposition to a skilled nursing facility (OR 2.30, 95% CI 1.58-3.35), and total parathyroidectomy with autotransplantation (OR 1.27, 95% CI 1.06-1.52). Advancing age (OR 0.98, 95% CI 0.98-0.99) and surgery at a high-volume hospital (OR 0.53, 95% CI 0.36-0.77) were protective against readmission. CONCLUSIONS: Patients undergoing parathyroidectomy for RHPT have a high readmission rate, most frequently for metabolic complications. Increased postoperative vigilance, which may include outpatient laboratory monitoring, may be indicated in patients with risk factors for readmission.

Nictitating membrane fixation improves stability of the contact lens on the animal corneal surface.

We evaluated the feasibility and safety of nictitating membrane fixation to address reduced contact lens stability by the nictitating membrane in a rabbit model. Under general anesthesia, twelve animals received a horizontal mattress suture between the nictitating membrane and the upper eyelid of one eye. To assess the effects of this technique and secondary side effects, contact lens stability test, Schirmer tear test, tear break-up time measurement, eye tissue pathology and morphology were evaluated. Contact lens stability was increased after nictitating membrane fixation. The percentage of contact lens retention in the nictitating membrane fixed rabbit after 4 hours was 90% whereas that in the untreated rabbit was 42.5%. In addition, there were no significant differences in tear quantity and quality between the fixed and untreated eyes. Furthermore, no remarkable pathological lesions were found in gross observation during the 1-month time period or the following pathological examination. In this study, we demonstrated that nictitating membrane fixation increases contact lens stability without specific side effects using a rabbit model. This minimally invasive procedure could be useful when designing animal models for testing new contact lenses and has potential to apply to other biomaterial research on the ocular surface.

Restoration of Polyamine Metabolic Patterns in In Vivo and In Vitro Model of Ischemic Stroke following Human Mesenchymal Stem Cell Treatment.

We investigated changes in PA levels by the treatment of human bone-marrow-derived mesenchymal stem cells (hBM-MSCs) in ischemic stroke in rat brain model and in cultured neuronal SH-SY5Y cells exposed to oxygen-glucose deprivation (OGD). In ischemic rat model, transient middle cerebral artery occlusion (MCAo) was performed for 2 h, followed by intravenous transplantation of hBM-MSCs or phosphate-buffered saline (PBS) the day following MCAo. Metabolic profiling analysis of PAs was examined in brains from three groups: control rats, PBS-treated MCAo rats (MCAo), and hBM-MSCs-treated MCAo rats (MCAo + hBM-MSCs). In ischemic cell model, SH-SY5Y cells were exposed to OGD for 24 h, treated with hBM-MSCs (OGD + hBM-MSCs) prior to continued aerobic incubation, and then samples were collected after coculture for 72 h. In the in vivo MCAo ischemic model, levels of some PAs in brain samples of the MCAo and MCAo + hBM-MSCs groups were significantly different from those of the control group. In particular, putrescine, cadaverine, and spermidine in brain tissues of the MCAo + hBM-MSCs group were significantly reduced in comparison to those in the MCAo group. In the in vitro OGD system, N (1)-acetylspermidine, spermidine, N (1)-acetylspermine, and spermine in cells of the OGD + hBM-MSCs group were significantly reduced compared to those of OGD group.

Evaluation of the biocompatibility of regenerated cellulose hydrogels with high strength and transparency for ocular applications.

Prompt emergency treatment for ocular injury, particularly in a battlefield setting, is essential to preserve vision, reduce pain, and prevent secondary infection. A bandage contact lens that could be applied in the field, at the time of injury, would protect the injured ocular surface until hospital treatment is available. Cellulose, a natural polymer, is widely used in biomedical applications including bandage materials. Hydrogels synthesized from different cellulose sources, such as plants, cotton, and bacteria, can have the optical transparency and mechanical strength of contact lenses, by tailoring synthesis parameters. Thus, we optimized the fabrication of cellulose-based hydrogels and evaluated their in vivo biocompatibility and related physical properties. Our data demonstrate that along with tailorable physical properties, our novel cellulose-based hydrogels could be made with contact lens geometry, exhibit no significant signs of material toxicity after 22 days of in vivo testing, and show significant promise for use as a corneal bandage immediately following ocular trauma.

Physical and Biological Characterization of the Gamma-Irradiated Human Cornea.

PURPOSE: To compare the physical and biological characteristics of commercial gamma-irradiated corneas with those of fresh human corneas and to determine suitability for transplantation. METHODS: The physical properties of gamma-irradiated and fresh corneas were evaluated with respect to light transmittance, hydration (swelling ratio), elastic modulus (compressive modulus by the indentation method), matrix organization (differential scanning calorimetry), and morphology (light and transmission electron microscopy). The biological properties of the gamma-irradiated cornea, including residual cell content and cellular biocompatibility, were evaluated by quantifying DNA content and measuring the proliferation rate of human corneal epithelial cells, respectively. RESULTS: The hydration, light transmittance, elastic modulus, and proliferation rate of human corneal epithelial cells were not significantly different between fresh and gamma-irradiated corneas. However, differences were observed in tissue morphology, DNA content, and thermal properties. The density of collagen fibrils of the gamma-irradiated corneal sample (160.6 ± 33.2 fibrils/µm) was significantly lower than that of the fresh corneal sample (310.0 ± 44.7 fibrils/µm). Additionally, in the gamma-irradiated corneas, cell fragments-but not viable cells-were observed, supported by lower DNA content of the gamma-irradiated cornea (1.0 ± 0.1 µg/mg) than in fresh corneas (1.9 µg/mg). Moreover, the denaturation temperature of gamma-irradiated corneas (61.8 ± 1.1 °C) was significantly lower than that of fresh corneas (66.1 ± 1.9 °C). CONCLUSIONS: Despite structural changes due to irradiation, the physical and biological properties of the gamma-irradiated cornea remain similar to the fresh cornea. These factors, combined with a decreased risk of rejection and longer shelf life, make the gamma-irradiated tissue a viable and clinically desired option in various ophthalmic procedures.

Metacognitive Performance, the Tip-of-Tongue Experience, Is Not Disrupted in Parkinsonian Patients.

The present study investigated whether a form of metamemory, the tip-of-tongue phenomenon (TOT), was affected in patients with Parkinson's disease (PD). The PD patient (n = 22), age-matched elderly control (n = 22), and college student control (n = 46) groups were compared on a motor timing task and TOT measures. Motor timing was assessed using a cued hand-clapping task, whereas TOT was assessed using general knowledge questions. The results indicated that motor timing was significantly impaired in the PD group relative to both control groups. However, all of the TOT metacognitive measures: frequency, strength, and accuracy were statistically equivalent between the PD patients and elderly control groups, both of whom showed significantly better memory performance than college controls. These findings demonstrate that TOT metamemory is not compromised in PD patients, and that further insight into TOT mechanisms in PD may prove helpful in developing novel intervention strategies to enhance memory and general cognitive functions in these patients.