The presence of herpes simplex-1 and varicella zoster viruses is not related with clinical outcome of Bell's Palsy

Bell's Palsy is the most frequent acute neuropathy of cranial nerves; it has been associated in various reports to herpes viruses. In a prospective study we searched the presence of DNA from five herpes viruses (HSV-1 and 2, VZV, EBV and HHV-6) in 79 patients at the acute phase of Bell's Palsy. Results were related with various parameters; age, gender and clinical outcome. We found the significant presence (p˂0.001) of HSV-1 and VZV in 39% and 42% of patients. However, a large percentage of cases were negative. When comparisons were made between subgroups according to gender and age no differences were found with viral findings nor with clinical outcome of palsy, which was of clinical remission in most cases (78%). Our results suggest that herpes viruses might participate in the complex mechanisms of autoimmunity of Bell's Palsy but not as determinant etiological element.

The Effect of Hurricane Maria on the Surgical Workload of the UPR-affiliated Hospitals

OBJECTIVE

The Caribbean islands are regularly affected by hurricanes in a seasonal manner, but major (category 4 and 5) hurricanes are infrequent, and what happens in their aftermath is important for future planning.

METHODS

We reviewed the surgical cases entered into the University of Puerto Rico (UPR) General Surgery Department database from January 1, 2016, through December 31, 2017. This database collects patient and procedural information from the surgical services of the UPR-affiliated hospitals. To analyze the impact that Hurricane Maria had on the surgical population, we compared cases per month using September 2017 (the month that Maria struck Puerto Rico) as the reference month. A chi-square goodness-of-fit test was used to evaluate differences between months.

RESULTS

Information was available for 9,059 cases during the study period. The mean age of the group was 49±14 years, the gender distribution being 56% women, 44% men. The study found a statistically significant difference (p<0.001) in the number of surgical cases per month, with fewer patients in September 2017 (n = 210) compared to other months, representing a 57% decline in the number of cases. These patients tended to be sicker, with an increase in the number who had an American Society of Anesthesiologists physical status classification of 3 or greater. Within 3 months after the natural disaster, the volume of patients started to return to normal.

CONCLUSION

We found that this major hurricane resulted in a decreased surgical workload, mostly because elective surgery cases were fewer, but that the patients that came for surgical care tended to be sicker and had, for the most part, poorly controlled systemic diseases. The volume of surgical cases did not reach normal levels until 3 months after the natural disaster.

Physical characteristics of nano-Hydroxyapatite Pickering-emulsions and their adjuvant activity on the antibody response towards the Bothros asper snake venom

Emulsions are crucial in the treatment of snake bites to bust the antibody response of the inmunogen. The widely used Freund's emulsion typically combines 50/50 water-oil (W/O) phase. However, its use is limited because it is associated with tissue damage. We formulated and characterized a Pickering Emulsion 70/30 (W/O) that uses a chemically modified hydrophobic hydroxyapatite as surfactant. This Pickering emulsion has similar rheologic behavior to Freund's emulsion 50/50, but with lower oil and surfactant concentration. Evaluation of cell recruitment, antibody response and adhering tissue in mice immunized with B. asper of Pacific venom and treated with Freund's and Pickering 70/30 emulsions resulted in similar adjuvant activity (only 18% lower in Pickering 70/30 emulsion). However, Pickering 70/30 emulsions minimized negative side effects in the host animals and showed better ease of flow that favors injection of the host. Our results open up room for optimization and improvement of Pickering emulsion based on modified nanoparticles for medical applications.

Field-induced phase transitions of repulsive spin-1 bosons in optical lattices

We study the phase diagram of repulsively interacting spin-1 bosons in optical lattices at unit filling, showing that an externally induced quadratic Zeeman effect may lead to a rich physics characterized by various phases and phase transitions. We find that the main properties of the system may be described by an effective field model, which provides the precise location of the phase boundaries for any dimension, in excellent agreement with our numerical calculations for one-dimensional (1D) systems. Thus, our work provides a quantitative guide for the experimental analysis of various types of field-induced quantum phase transitions in spin-1 lattice bosons. These transitions, which are precluded in spin-1/2 systems, may be realized by using an externally modified quadratic Zeeman coupling, similar to recent experiments with spinor condensates in the continuum.

Mott-insulator phases of spin-3/2 fermions in the presence of quadratic Zeeman coupling

We study the influence of the quadratic Zeeman effect on the Mott-insulator phases of hard-core 1D spin-3/2 fermions. We show that, contrary to spinor bosons, the quadratic Zeeman coupling preserves an SU(2)⊗SU(2) symmetry, leading for large-enough quadratic Zeeman coupling to an isotropic pseudo-spin-1/2 Heisenberg antiferromagnet. Decreasing the quadratic Zeeman coupling, this phase undergoes, depending on the scattering lengths, either a Kosterlitz-Thouless transition into a gapped dimerized phase or a commensurate-incommensurate transition into a gapless spin liquid. This rich phase diagram can be observed experimentally in four-component fermions in optical lattices under similar entropy constraints to those needed for Néel order in spin-1/2 gases.

Expectancy for food or expectancy for chocolate reveals timing systems for metabolism and reward

The clock gene protein Per 1 (PER1) is expressed in several brain structures and oscillates associated with the suprachiasmatic nucleus (SCN). Restricted feeding schedules (RFS) induce anticipatory activity and impose daily oscillations of c-Fos and clock proteins in brain structures. Daily access to a palatable treat (chocolate) also elicits anticipatory activity and induces c-Fos expression mainly in corticolimbic structures. Here the influence of daily access to food or chocolate was explored by the analysis of the oscillatory patterns of PER1 in hypothalamic and corticolimbic structures. Wistar rats were exposed to RFS or to daily access to chocolate for 3 weeks. Persistence of food or chocolate entrained rhythms was determined 8 days after cessation of the feeding protocols. RFS and chocolate induced a phase shift in PER1 rhythmicity in corticolimbic structures with peak values at zeitgeber time 12 and a higher amplitude in the chocolate group. Both RFS and chocolate groups showed an upregulation of PER1 in the SCN. Food and chocolate entrained rhythms persisted for 8 days in behavior and in PER1 expression in the dorsomedial hypothalamic nucleus, accumbens, prefrontal cortex and central amygdala. The present data demonstrate the existence of different oscillatory systems in the brain that can be activated by entrainment to metabolic stimuli or to reward and suggest the participation of PER1 in both entraining pathways. Persistence and amplification of PER1 oscillations in structures associated with reward suggest that this oscillatory process is fundamental to food addictive behavior.

Dialysis outcomes in Colombia (DOC) study: a comparison of patient survival on peritoneal dialysis vs hemodialysis in Colombia

The goal of the Dialysis Outcomes in Colombia (DOC) study was to compare the survival of patients on hemodialysis (HD) vs peritoneal dialysis (PD) in a network of renal units in Colombia. The DOC study examined a historical cohort of incident patients starting dialysis therapy between 1 January 2001 and 1 December 2003 and followed until 1 December 2005, measuring demographic, socioeconomic, and clinical variables. Only patients older than 18 years were included. As-treated and intention-to-treat statistical analyses were performed using the Kaplan-Meier method and Cox proportional hazard model. There were 1094 eligible patients in total and 923 were actually enrolled: 47.3% started HD therapy and 52.7% started PD therapy. Of the patients studied, 751 (81.3%) remained in their initial therapy until the end of the follow-up period, death, or censorship. Age, sex, weight, height, body mass index, creatinine, calcium, and Subjective Global Assessment (SGA) variables did not show statistically significant differences between the two treatment groups. Diabetes, socioeconomic level, educational level, phosphorus, Charlson Co-morbidity Index, and cardiovascular history did show a difference, and were less favorable for patients on PD. Residual renal function was greater for PD patients. Also, there were differences in the median survival time between groups: 27.2 months for PD vs 23.1 months for HD (P=0.001) by the intention-to-treat approach; and 24.5 months for PD vs 16.7 months for HD (P<0.001) by the as-treated approach. When performing univariate Cox analyses using the intention-to-treat approach, associations were with age > or =65 years (hazard ratio (HR)=2.21; confidence interval (CI) 95% (1.77-2.755); P<0.001); history of cardiovascular disease (HR=1.96; CI 95% (1.58-2.90); P<0.001); diabetes (HR=2.34; CI 95% (1.88-2.90); P<0.001); and SGA (mild or moderate-severe malnutrition) (HR=1.47; CI 95% (1.17-1.79); P=0.001); but no association was found with gender (HR=1.03, CI 95% 0.83-1.27; P=0.786). Similar results were found with the as-treated approach, with additional associations found with Charlson Index (0-2) (HR=0.29; Cl 95% (0.22-0.38); P<0.001); Charlson Index (3-4) (HR=0.61; Cl 95% (0.48-0.79); P<0.001); and SGA (mild-severe malnutrition) (HR=1.43; Cl 95% (1.15-1.77); P<0.001). Similarly, the multivariate Cox model was run with the variables that had shown association in previous analyses, and it was found that the variables explaining the survival of patients with end-stage renal disease in our study were age, SGA, Charlson Comorbidity Index 5 and above, diabetes, healthcare regimes I and II, and socioeconomic level 2. The results of Cox proportional risk model in both the as-treated and intention-to-treat analyses showed that there were no statistically significant differences in survival of PD and HD patients: intention-to-treat HD/PD (HR 1.127; CI 95%: 0.855-1.484) and as-treated HD/PD (HR 1.231; CI 95%: 0.976-1.553). In this historical cohort of incident patients, there was a trend, although not statistically significant, for a higher (12.7%) adjusted mortality risk associated with HD when compared to PD, even though the PD patients were poorer, were more likely to be diabetic, and had higher co-morbidity scores than the HD patients. The variables that most influenced survival were age, diabetes, comorbidity, healthcare regime, socioeconomic level, nutrition, and education.

[Red tide bloom produced by Lingulodinium polyedrum (Peridiniales, Dinophyceae) in Bahía Culebra, Papagayo Gulf, Costa Rica]

This is the first record of the dinoflagellate Lingulodinium polyedrum in a red tide bloom in the North Pacific coast of Costa Rica. The sample was collected on April 2000 at Culebra Bay, Gulf of Papagayo, from a patch of aproximatly 2000 m2, which produced a red discoloration of the water and a peculiar strong odor. This species produces spherical hypnocysts that may remain for decades when dark or anoxic conditions are present; L. polyedrum had been associated with the production of paralyzing toxins such as saxitoxins and yessotoxins. A second smaller patch was observed close Panama beach, into the bay, where we found seven puffer fish (Diodontidae) and two lobsters dead in the sand. It is important to develop a monitoring program to identify seasonal behavior of this species and ameliorate its impact on coastal human communities.