Positive Lymph Node Ratio as an Indicator of Prognosis and Local Tumor Clearance in N3 Gastric Cancer

Background

Nodal metastasis is an important clinical issue in gastric cancer patients. This study was designed to investigate the clinical usefulness of the positive lymph node ratio (PLNR), which reflects both metastatic and retrieved lymph node numbers, in patients with pN3 gastric cancer.

Methods

We retrospectively analyzed the records of 138 consecutive pN3 patients who underwent curative gastrectomy with lymphadenectomy from 2000 to 2012.

Results

A PLNR of 0.4 was proved to be the best cutoff value to stratify the prognosis of patients with pN3 gastric cancer (P?<?0.001). Univariate and multivariate analyses revealed that older age, larger tumor size (≥10 cm), and PLNR?≥?0.4 [P?<?0.001, HR 3.1 (95 % CI 1.7–5.4)] were independent prognostic factors in pN3 gastric cancer. Regarding the recurrence, patients with PLNR <0.4 had a significantly lower rate of lymph node recurrence than those with PLNR ≥0.4 (P?=?0.020). There was no significant difference in the lymph node recurrence rate between N3a and N3b patients in the PLNR <0.4 group [P?=?0.546, 11.6 % (7/60) vs. 12.5 (1/8)], indicating a better local control regardless of pN3 subgroups.

Conclusions

PLNR is useful to stratify the prognosis and evaluate the extent of local tumor clearance in pN3 gastric cancer.

     

Amounts of sweat and salt loss due to sweating during a three-hour badminton practice in summer

In 7 men and 5 women, we measured the amounts of sweat and fluid intake, and the ionic composition of sweat during a 3-hour badminton practice in summer. The amount of sweat was calculated as follows; body weight before practice (g)--body weight after practice (g)--urine volume (ml) +fluid intake (ml). We collected sweat by covering the non-dominant forearm with a plastic bag. The amounts of sweat and fluid intake during the 3-hour practice were 1809 +/- 715ml (mean +/- SD) and 658 +/- 344ml, respectively. Weight loss after the practice was 2.0 +/- 0.9% of their weight before the practice. The Na(+) and Cl(-) levels of the sweat about 30 min after the start of practice were 66 +/- 34 mEq/l and 54 +/- 32mEq/l, respectively. There was no significant difference between those ionic levels of the sweat about 30 min after the start of practice and those about 30 min before the end of practice. The sum of Na(+) and Cl(-) loss into sweat during a 3-hour practice session was supposed to be 6.9 +/- 5.3g, and to be above 10 g in 4 of 7 men, assuming that there were no regional differences in the ionic composition of sweat. The findings suggested that most of the participants should take more fluid and some of them might need salt intake during the practice.     

PREGS induces LTP in the hippocampal dentate gyrus of adult rats via the tyrosine phosphorylation of NR2B coupled to ERK/CREB [corrected] signaling

An acute application of neurosteroid pregnenolone sulfate (PREGS) to hippocampal slices from adult rats induced a long-lasting potentiation (LLP PREGS) at the perforant path-granule cell synapse. As a partial mechanism of the LLP PREGS, we previously revealed that PREGS transiently increases the probability of presynaptic glutamate release via a sensitization of alpha7-nicotinic acetylcholine receptor (alpha7nAChR). We herein demonstrate that the LLP PREGS could be separated into two independent processes: the above-mentioned early presynaptic-origin short-term potentiation (STP PREGS) and a delayed postsynaptic N-methyl-d-aspartate receptor (NMDAr)-dependent long-term potentiation termed LTP(PREGS). This study focused on the analysis of the signaling mechanism underlying the LTP PREGS. PREGS increased the tyrosine phosphorylation of NR2B, a subunit of NMDAr, and the NMDAr-mediated Ca2+ influx in the granule cells. The enhanced Ca2+ influx was largely attenuated by the NR2B subunit inhibitor ifenprodil and the Src kinase family inhibitor PP2. PREGS also triggered a persistent phosphorylation of extracellular signal-regulated kinase 2 (ERK2) followed by an ERK-dependent phosphorylation of cAMP-response element-binding protein (CREB), which was crucial for the LTP PREGS induction and was sensitive to ifenprodil. These results suggest that PREGS induces an acute increase in the NR2B tyrosine phosphorylation which enhances the Ca2+ influx through NMDAr, followed by an activation of the ERK/CREB signaling cascade that leads to LTP PREGS.     

Endocrine disrupting chemicals, 4‐nonylphenol,bisphenol A and butyl benzyl phthalate,impair metabolism of estradiol in male and female rats as assessed by levels of 15α‐hydroxyestrogens and catechol estrogens in urine

Bisphenol A (BPA), 4‐nonylphenol (NP) and butyl benzyl phthalate (BBP), termed endocrine‐disrupting chemicals, are known to mimic estrogen activity. The effects of these chemicals on 17β‐estradiol (E₂) metabolism in vivo in rats were examined. Male and female rats were given NP (250 mg kg^–1 day^–1), BPA (250 μg kg^–1 day^–1) or BBP (500 mg kg^–1 day^–1) by gavage for 14 days, followed by a single intraperitoneal injection of E₂ (5 mg kg^–1) on the final day. The urinary excretion over 72 hours of 2‐hydroxyestrone 1‐N‐acetylcysteine thioether, 2‐hydroxyestrone 4‐N‐acetylcysteine thioether, 4‐hydroxyestrone 2‐N‐acetylcysteine thioether, 2‐hydroxy‐17β‐estradiol (2‐OHE₂), 2‐hydroxyestrone (2‐OHE₁), 4‐hydroxy‐17β‐estradiol, 4‐hydroxyestrone, 15α‐hydroxyestriol (E₄), 15α‐hydroxy‐17β‐estradiol and 15α‐hydroxyestrone was measured. Increases in urinary excretion of 2‐OHE₁ and decreases in E₄ were observed in males treated with NP or BBP. Decreases in urinary excretion of 2‐OHE₂ and E₄ were observed in males treated with BPA. Decreases in urinary excretion of 2‐OHE₁ and 2‐OHE₂ were observed in females treated with BBP. Normalized liver and weights were increased in both sexes treated with NP or BBP. Histologic observations revealed marked changes in the distal tubules and collecting ducts in the kidneys of rats exposed to NP and BBP, and hypertrophy in the hepatocytes of the centrilobular zone of the liver. No BPA‐related effects on organ weight and on liver or kidney histopathology were found. These results suggest that the 14 day oral dosing of NP and BBP disrupted E₂ metabolism, resulting from marked morphological and functional alterations in the liver and kidneys. In addition, BPA could induce metabolic and endocrine disruption.     

High preoperative hemoglobin A1c is a risk factor for surgical site infection after posterior thoracic and lumbar spinal instrumentation surgery

Background

Diabetes mellitus (DM) is reported to be a risk factor for surgical site infection (SSI), which is a serious complication after spinal surgery. The effect of DM on SSI after instrumented spinal surgery remains to be clarified. The aim was to elucidate perioperative risk factors for infection at the surgical site after posterior thoracic and lumbar spinal arthrodesis with instrumentation in patients with DM.

Methods

Consecutive patients who underwent posterior instrumented thoracic and lumbar spinal arthrodesis during the years 2005–2011, who could be followed for at least 1 year after surgery, were included. These included 36 patients with DM (19 males and 17 females; mean age 64.3 years). The patients’ medical records were retrospectively reviewed to determine the SSI rate. The characteristics of the DM patients were examined in detail, including the levels of serum glucose and HbA1c, which indicate the level of diabetes control.

Results

Patients with DM had a higher rate of SSI (6 of 36 patients, 16.7 %) than patients without DM (10 of 309 patients, 3.2 %). Although the perioperative serum glucose level did not differ between DM patients that did or did not develop SSI, the preoperative HbA1c value was significantly higher in the patients who developed SSI (7.6 %) than in those who did not (6.9 %). SSI developed in 0.0 % of the patients with controlled diabetes (HbA1c <7.0 %) and in 35.3 % of the patients with uncontrolled diabetes (HbA1c ≥7.0 %).

Conclusions

DM patients whose blood glucose levels were poorly controlled before surgery were at high risk for SSI. To prevent SSI in DM patients, we recommend lowering the HbA1c to <7.0 % before performing surgery.     

Factors contributing to improvement of syringomyelia after foramen magnum decompression for Chiari type I malformation

Background

Although various surgical approaches have been proposed for treating syringomyelia associated with Chiari type I malformation, a standard method has yet to be established. we prospectively investigated the results of our surgical method: foramen magnum decompression combined with C1 laminectomy and excision of the outer layer of the dura mater.

Methods

Twenty patients underwent surgery between 2000 and 2010 at our hospital. After surgery, the size of the syrinx decreased in 11 patients (decreased group) but remained unchanged in nine patients (unchanged group). The following parameters were compared: age at the time of surgery, duration of morbidity, improvement of preoperative symptoms, morphological type and length of the syrinx, presence or absence of scoliosis, cervical alignment, basal and clivo-axial angles, and postoperative subarachnoid space at the foramen magnum level.

Results

Preoperative symptoms improved in all patients in the decreased group but in only one patient in the unchanged group. The average duration of morbidity was significantly shorter in the decreased group. Morphological examination revealed that the size of all central-type syrinxes decreased after surgery, whereas in all cases of deviated-type syrinx, size was unchanged. The average length of preoperative syrinx was significantly shorter in the decreased group. The postoperative subarachnoid space at the foramen magnum was enlarged in the entire decreased group, whereas residual narrowing of the space was observed in 44 % of patients in the unchanged group. No significant intergroup differences were observed in the other factors.

Conclusions

In patients with syringomyelia, a longer and deviated type of syrinx, a longer duration of morbidity, and postoperative residual narrowing of the subarachnoid space are associated with a poor prognosis after the surgical procedure. The pathogenesis of syringomyelia is inconsistent, and the choice of surgical technique for each pathological condition is important.