Use of Antibiotics and Risk of Cancer: A Systematic Review and Meta-Analysis of Observational Studies

The association between antibiotic use and risk of cancer development is unclear, and clinical trials are lacking. We performed a systematic review and meta-analysis of observational studies to assess the association between antibiotic use and risk of cancer. PubMed, the Cochrane Library and EMBASE were searched from inception to 24 February 2019 for studies reporting antibiotic use and subsequent risk of cancer. We included observational studies of adult subjects with previous exposure to antibiotics and available information on incident cancer diagnoses. For each of the eligible studies, data were collected by three reviewers. Risk of cancer was pooled to provide an adjusted odds ratio (OR) with a 95% confidence interval (CI). The primary outcome was the risk of developing cancer in ever versus non-antibiotic users. Cancer risk’s association with antibiotic intake was evaluated among 7,947,270 participants (n = 25 studies). Overall, antibiotic use was an independent risk factor for cancer occurrence (OR 1.18, 95%CI 1.12–1.24, p < 0.001). The risk was especially increased for lung cancer (OR 1.29, 95%CI 1.03–1.61, p = 0.02), lymphomas (OR 1.31, 95%CI 1.13–1.51, p < 0.001), pancreatic cancer (OR 1.28, 95%CI 1.04–1.57, p = 0.019), renal cell carcinoma (OR 1.28, 95%CI 1.1–1.5, p = 0.001), and multiple myeloma (OR 1.36, 95%CI 1.18–1.56, p < 0.001). There is moderate evidence that excessive or prolonged use of antibiotics during a person’s life is associated with slight increased risk of various cancers. The message is potentially important for public health policies because minimizing improper antibiotic use within a program of antibiotic stewardship could also reduce cancer incidence.

Biological and Synthetic Conduits in Peripheral Nerve Repair: A Comparative Experimental Study

Two different types of conduits, one biological, obtained with homologous glutaraldehyde preserved vein segments and the other synthetic bioabsorbable, made with Poly [L-lactide-co-6-caprolactone], were evaluated as guides for nerve repair in alternative to autologous grafts in an experimental animal model. Under general anesthetic, the ischiatic nerve of a number Wistar rats was transected to create a 1 cm gap, which was then repaired by means of the conduits or autologous grafts. Controls were performed at 1, 3 and 6 months; nerve regeneration was effective with both conduits, but the count of myelinated axons showed a significant difference between the synthetic and biological tubes (p<0.001). The Poly [L-lactide-co-6-caprolactone] guide was still intact 30 days after implant; progressive signs of degradation were present at 90 and 180 days. These results show that the synthetic conduits are better than those obtained with preserved vein segments and might be considered in alternative to autologous grafts in peripheral nerve reconstruction

Biventricular Arrhythmogenic Cardiomyopathy: a paradigmatic case

<p>We present a case of arrhythmogenic cardiomyopathy with biventricular involvement and strong&nbsp;arrhythmic substrate, highlighting&nbsp;the need to consider more than a single diagnostic option when facing arrhythmic presentations in young patients&nbsp;and&nbsp;the growing contribution provided by the genetic laboratory and contrast CMR to clinical management.</p>

Superior muscle reinnervation after autologous nerve graft or poly-L-lactide-epsilon-caprolactone (PLC) tube implantation in comparison to silicone tube repair

Recovery after peripheral nerve injury depends not only on the amount of reinnervation, but also on its accuracy. The rat sciatic nerve was subjected to an 8 mm long gap lesion repaired either by autograft (AG, n = 6) or tubulization with impermeable silicone tube (SIL, n = 6) or permeable tube of poly-L-lactide-epsilon-caprolactone (PLC, n = 8). Recordings of the compound muscle action potential (CMAP) from gastrocnemius (mGC), tibialis anterior (mTA) and plantar (mPL) muscles were performed 90 days after injury to assess the amount of muscle reinnervation. The CMAP amplitude achieved in mGC, mTA and mPL was similar in after nerve autograft (39%, 42%, 22% of control values) and PLC tube implantation (37%, 36%, 24%) but lower with SIL tube (29%, 30%, 14%). The nerve fascicles projecting into each of these muscles were then transected and retrograde tracers (Fluoro Gold, Fast Blue, DiI) were applied to quantify the percentage of motoneurons with single or multiple branches to different targets. The total number of labeled motoneurons for the three muscles did not differ in autografted rats (1186 +/- 56; mean +/- SEM) with respect to controls (1238 +/- 82), but was reduced with PLC tube (802 +/- 101) and SIL tube (935 +/- 213). The percentage of neurons with multiple projections was lower after autograft and PLC tube (6%) than with SIL tube (10%). Considering the higher CMAP amplitude and lower number of neurons with multiple projections, PLC nerve conduits seem superior to SIL tubes and a suitable alternative to autografts for the repair of long gaps.

Peripheral nerve regeneration through bioresorbable and durable nerve guides

We compared reinnervation of target organs after sciatic nerve resection and repair by tubulization with biodurable tubes of silicone and teflon, or bioresorbable nerve guides of collagen and poly(L-lactide-co-6-caprolactone) (PLC) leaving a 6 mm gap in different groups of mice. All tubes were of 1 mm inside diameter and thin-walled (50 to 250 microm). Functional reinnervation was assessed by noninvasive methods to determine recovery of sweating, sensory and motor functions in the hindpaw repeatedly during 5 months postoperation. PLC guides allowed faster and higher levels of reinnervation for the four functions tested than collagen and silicone tubes, while teflon tubes gave the lowest levels of recovery. Regenerative reinnervation by thin nociceptive and sudomotor fibers was higher than by large sensory and alphamotor fibers in all groups. Resorbable tubes promoted regeneration in a higher proportion of mice than durable tubes. In cases with effective regeneration the nerve cable was multifascicular, with mild to moderate mononuclear cell infiltrates and a thin newly formed perineurium. The number of myelinated fibers was higher in PLC and silicone tubes than in collagen and teflon tubes. There was only minimal inflammatory reaction within the remnants of collagen tubes, but not in the other materials. PLC tubes of slow reabsorption rate seem useful for repairing long gaps in injured nerves.

Timing of disease progression by quantitative EEG in Alzheimer' s patients

This prospective study was planned to assess whether quantitative EEG (qEEG) can give an estimate of the timing of achievement of three endpoints (loss of activities of daily living, incontinence, and death) in 72 consecutive patients (53 females, 19 males; mean age, 70.8) affected with probable Alzheimer's disease, as defined according to the NINCDS-ADRDA criteria. Power-weighted, log-transformed relative values of the four conventional EEG bands were considered in a central-posterior temporal region for each hemisphere. The hypothesis was tested by the lifereg procedure of the Statistical Analysis System package (first significance level accepted, P < or = 0.01). Because patients were in different stages of the disease, the statistical analysis was performed in the entire group as well as in the subgroup of 41 patients (mean age, 69.6) with mild dementia (scoring 3 or 4 on the global deterioration scale). In the whole group, the loss of activities of daily living was predicted by delta power in either side (P = 0.01), incontinence was predicted by alpha power in the right side (P < 0.01), whereas the statistical significance was not reached for death (P < 0.05). In the subgroup of mild demented patients, the loss of activities of daily living was predicted by delta power in the left side (P = 0.01), incontinence by both delta (P < 0.01) and alpha (P < 0.001) power in the right side, and death was not significantly predicted (P = 0.08). Quantitative EEG is a low-cost, discomfort-free technique which may be used to obtain information on the timing of disease evolution. The results showed in mild Alzheimer's disease appear especially interesting to attempt a prediction of the future time course of the disease from its beginning.

EEG spectral profile to stage Alzheimer's disease

OBJECTIVE

The present study was undertaken to investigate whether a synoptic parameter of quantitative EEG (qEEG), such as the power spectral profile, may be used as a simple marker to stage Alzheimer's disease (AD) in the clinical setting.

METHODS

To this purpose, the qEEG spectral profile was examined in 48 patients (mean age: 73 years) with probable (NINCDS-ADRDA criteria) AD, who were divided into 4 groups, according to the Global Deterioration Scale (GDS; score: 3-6). The spectral profile of each patient was expressed by the relative power of seven frequency bands (2-3.5, 4-5.5, 6-7.5, 8-9.5, 10-11.5, 12-13.5, 14-22.5 Hz). Mean values in each of the four GDS groups as well as in a control group of 18 healthy elderly subjects underwent multivariate analysis of variance.

RESULTS

A normally shaped but shifted-to-the left spectral profile was found in GDS 3 group, whereas a reduced background rhythm with various increase in slow activity power characterized both GDS 4 and 5 groups. Finally, an 'exponential asymptotic' profile with the highest power in the lowest frequencies was the hallmark of GDS 6 group. Overall, the 4-5.5 Hz and the 10-11.5 Hz band powers showed the highest statistical significance in differentiating the patient groups between one another and from controls (P < 0.0001).

CONCLUSIONS

These data show that spectral profile is a very simple parameter which can be used to stage the disease on a pathophysiological basis.

Highly permeable polylactide-caprolactone nerve guides enhance peripheral nerve regeneration through long gaps

We compared regeneration and functional reinnervation after sciatic nerve resection and tubulization repair with bioresorbable guides of poly(L-lactide-co-epsilon-caprolactone) (PLC) and permanent guides of polysulfone (POS) with different degrees of permeability, leaving a 6 mm gap in different groups of mice. Functional reinnervation was assessed to determine recovery of motor, sensory and sweating functions in the hindpaw during four months postoperation. Highly permeable PLC guides allowed for faster and higher levels of reinnervation for the four functions tested than impermeable or low-permeable PLC guides, while semipermeable 30 and 100 kDa POS tubes yielded very low levels of reinnervation. The regeneration success rate was higher with PLC than with POS tubes. Morphometrical analysis of cross-sectional nerves under light microscopy showed the highest number of regenerated myelinated fibers at mid tube and distal nerve in high-permeable PLC guides. Impermeable PLC guides allowed slightly worse levels of regeneration, while low-permeable PLC guides promoted neuroma and limited distal regeneration. The lowest number of regenerated fibers were found in POS tubes. In summary, highly permeable bioresorbable PLC guides offer a suitable alternative for repairing long gaps in injured nerves, approaching the success of autologous nerve grafts.

Effect of transport and competition on ligand binding

We present a model to describe the physics of chemoreception in processes determined by competitive ligand binding. Our model describes the competition between various populations, such as ligands vs. blockers and receptors vs. decoys, in protein activation when diffusion is rate-determining. Full spatio-temporal solutions can be obtained numerically. The model structure is kept simple enough as to permit its easy generalization to describe a large subset of the manifold of possible situations occurring in nature. The power and simplicity of the proposed method are exhibited through the solution of several examples which are discussed in detail.

Effectiveness of a bioabsorbable conduit in the repair of peripheral nerves

A new conduit made with a bioabsorbable copolymer, poly (L-lactide-co-6-caprolactone), was evaluated in an animal model as a guide for nerve regeneration. The conduit had an inner diameter of 1.3 mm and a wall thickness of 175 microns. Segments of length 1.2 cm were interposed between the proximal and distal stumps of transected ischiatic nerves in Wistar rats, bridging a nerve gap of 1 cm. All of the procedure was performed under general anaesthesia using microsurgical techniques. Controls were performed at 1, 3 and 6 months and it was demonstrated that the conduit was still undamaged after 30 d. Progressive signs of degradation appeared at 90 and 180 d. Nerve regeneration in the lumen was effective as confirmed by histological and electron microscopical investigations. These preliminary results emphasize the interesting properties of the conduit with regard to the achievement of a neural prosthesis.

Biological and synthetic conduits in peripheral nerve repair: a comparative experimental study

Two different types of conduits, one biological, obtained with homologous glutaraldehyde preserved vein segments and the other synthetic bioabsorbable, made with Poly [L-lactide-co-6-caprolactone], were evaluated as guides for nerve repair in alternative to autologous grafts in an experimental animal model. Under general anesthetic, the ischiatic nerve of a number Wistar rats was transected to create a 1 cm gap, which was then repaired by means of the conduits or autologous grafts. Controls were performed at 1, 3 and 6 months; nerve regeneration was effective with both conduits, but the count of myelinated axons showed a significant difference between the synthetic and biological tubes (p < 0.001). The Poly [L-lactide-co-6-caprolactone] guide was still intact 30 days after implant; progressive signs of degradation were present at 90 and 180 days. These results show that the synthetic conduits are better than those obtained with preserved vein segments and might be considered in alternative to autologous grafts in peripheral nerve reconstruction.

[Moderate cardiac failure: oxygen consumption during exercise predicts ultrafiltration results]

Extracorporeal ultrafiltration (UF) can improve the clinical condition, as assessed by cardiopulmonary exercise evaluation, of patients with moderate heart failure (HF); the pre-UF level of physical performance above which UF does not induce clinical benefits, is not defined. For this purpose, we studied 29 patients with stable HF in functional class II-III (NYHA), who underwent UF (veno-venous bypass, removal of 1,830 +/- 550 ml of plasma water), regardless their baseline oxygen consumption at peak exercise (VO2p) and at anaerobic threshold (VO2AT). All patients experienced cardiopulmonary exercise tests (cycloergometer, increasing workloads of 25 W every 3 min) before (pre-UF), and 4 days and 3 months following UF. According to VO2 changes following UF 2 groups of patients were identified: in Group I (9 patients) no differences in VO2p and VO2AT were observed, while in Group II (18 patients) VO2p rose by 2.7 ml/min/kg (p < 0.001) at 4 days and 4.5 ml/min/kg (p = 0.04) at 3 months, and VO2AT rose by 1.2 ml/min/kg (p < 0.001) at 4 days and 2.8 ml/min/kg (p = 0.03) at 3 months. In unresponsive patients baseline values of VO2p > or = 18 ml/min/kg and VO2AT +/- 13 ml/min/kg were detected. Pre-UF VO2p inversely correlated with the shift of VO2p (delta VO2p) both at 4 days (r = -0.62, p < 0.001) and at 3 months (r = -0.53, p = 0.005), and pre-UF VO2AT inversely correlated with delta VO2AT at 4 days (r = -0.71, p < 0.001) and at 3 months (r = -0.63, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Sustained improvement in functional capacity after removal of body fluid with isolated ultrafiltration in chronic cardiac insufficiency: failure of furosemide to provide the same result

OBJECTIVES

This study was designed to investigate whether a subclinical accumulation of fluid in the lung interstitium associated with moderate congestive heart failure interferes with the patient's functional capacity, and whether furosemide treatment can promote reabsorption of the excessive fluid.

BACKGROUND

In patients with moderate congestive heart failure, pulmonary overhydration may be detected by chest roentgenography even if therapy is optimized to keep the urinary output normal and to prevent weight gain and dependent edema formation. Removal of the overhydration may help define its significance.

METHODS

Patients, whose regimens of digoxin, oral furosemide, and angiotensin-converting enzyme (ACE) inhibitor therapy were kept constant, were randomly allocated to receive ultrafiltration (8 cases) or an intravenous bolus of supplemental furosemide (mean dose: 248 mg; 8 cases). The amount of body fluid removed with each method approximated 1600 mL. Functional performance was assessed with cardiopulmonary exercise tests.

RESULTS

Soon after fluid withdrawal by either method, the filling pressures of the two ventricles and body weight were reduced and plasma renin activity, norepinephrine, and aldosterone were augmented. After furosemide administration, hormone levels remained elevated for the next 4 days, and during this period, patients had positive water metabolism, recovery of the elevated ventricular filling pressures, and re-occurrence of lung congestion with no improvement in functional capacity. After ultrafiltration, levels of renin, norepinephrine, and aldosterone fell to below control values within the first 48 hours and water metabolism was equilibrated at a new set point (less fluid intake and diuresis without weight gain). The favorable circulatory and ventilatory adjustments consequent to the reabsorption of lung water improved the functional capacity of these patients. That may also have restored the lung's ability to clear norepinephrine, thus restraining its facilitation of renin release. The improvement continued 3 months after the procedure.

CONCLUSIONS

In patients with congestive heart failure the set point of fluid balance is altered in spite of oral furosemide therapy; supplemental intravenous furosemide does not shift the set point, at least not when combined with ACE inhibition. Excessive, although asymptomatic, lung water limits the functional capacity of the patient.

Preparation of a new nerve guide from a poly(L-lactide-co-6-caprolactone)

A copolymer of L-lactide and 6-caprolactone (50:50, w/w) was synthesized and characterized. The thermal behaviour of this material did not show any crystallinity for several months; only after more than 1 yr of aging at room temperature and, particularly, in the in vitro degradation tests did it partially crystallize. The values of tensile strength, percent elongation at break and elastic modulus were, respectively, 25 MPa, 490% and 3 MPa. Transparent, elastic nerve guides having inner diameter of 1.3 mm and wall thickness of 175 microns were prepared.