Human Mitragynine and 7-Hydroxymitragynine Pharmacokinetics after Single and Multiple Daily Doses of Oral Encapsulated Dried Kratom Leaf Powder

Kratom leaves, consumed by millions worldwide as tea or ground leaf powder, contain multiple alkaloids, with mitragynine being the most abundant and responsible for most effects. Mitragynine is a partial µ-opioid receptor agonist and competitive antagonist at κ- and δ-opioid receptors; however, unlike morphine, it does not activate the β-arrestin-2 respiratory depression pathway. Due to few human mitragynine data, the largest randomized, between-subject, double-blind, placebo-controlled, dose-escalation study of 500-4000 mg dried kratom leaf powder (6.65-53.2 mg mitragynine) was conducted. LC-MS/MS mitragynine and 7-hydroxymitragynine plasma concentrations were obtained after single and 15 daily doses. Mitragynine and 7-hydroxymitragynine Cmax increased dose proportionally, and AUC was slightly more than dose proportional. The median mitragynine Tmax was 1.0-1.3 h after single and 1.0-1.7 h after multiple doses; for 7-hydroxymitragynine Tmax, it was 1.2-1.8 h and 1.3-2.0 h. Steady-state mitragynine concentrations were reached in 8-9 days and 7-hydroxymitragynine within 7 days. The highest mean mitragynine T1/2 was 43.4 h after one and 67.9 h after multiple doses, and, for 7-hydroxymitragynine, it was 4.7 and 24.7 h. The mean 7-hydroxy-mitragynine/mitragynine concentration ratios were 0.20-0.31 after a single dose and decreased (0.15-0.21) after multiple doses. These mitragynine and 7-hydroxymitragynine data provide guidance for future clinical kratom dosing studies and an interpretation of clinical and forensic mitragynine and 7-hydroxymitragynine concentrations.

Safety and Performance of Bone-Anchored Prostheses in Persons with a Transfemoral Amputation: A 5-Year Follow-up Study

BACKGROUND

For almost 30 years, bone-anchored prostheses have offered an alternative solution to prosthetic sockets by attaching the artificial limb directly to the femoral residuum by means of an osseointegration implant. Osseointegration implant surgery was introduced in our center in 2009. The aim of the present study is to report on safety, prosthesis-wearing time, and health-related quality-of-life (HRQoL) for patients with femoral bone-anchored prostheses during a 5-year follow-up period.

METHODS

All patients who underwent implantation of a press-fit osseointegration implant between May 2009 and November 2013 were eligible for the present study. Implantation was performed in 2 stages. Adverse events included infectious complications (grade 1 to 4), aseptic loosening, breakage, stoma-redundant tissue, and stoma hypergranulation. Prosthesis-wearing time and HRQoL were measured with the Questionnaire for Persons with a Transfemoral Amputation (Q-TFA) prosthetic use score and global score, respectively.

RESULTS

Thirty-nine of 42 eligible patients were included. Thirty patients (77%) presented with some kind of infection (156 events in total), with 148 (95%) events being classified as grade 1 or 2 and 8 events (5%) being classified as grade 3; the latter 8 events occurred in 4 patients. There were no instances of septic loosening. The intramedullary stem of the osseointegration implant broke in 2 patients. In total, soft-tissue refashioning had to be done 30 times in 14 patients. The Q-TFA median prosthetic use and global scores improved significantly from 71 to 100 and from 33 to 75, respectively (p < 0.001).

CONCLUSIONS

Despite the adverse events, patient prosthetic use and HRQoL improved significantly. Grade-1 and 2 infections were frequent but could mostly be treated with nonoperative measures. Most infections seemed to occur in the first 2 years and did not lead to deep infections. Two broken intramedullary stems were revised successfully. Current developments focus on reduction of infectious complications and prevention of osseointegration implant breakage.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Safety, prosthesis wearing time and health-related quality of life of lower extremity bone-anchored prostheses using a press-fit titanium osseointegration implant: A prospective one-year follow-up cohort study

BACKGROUND

We described safety and functional one-year follow-up outcomes of individuals with lower limb amputation treated with bone-anchored prostheses using titanium press-fit osseointegration implants.

METHODS

All consecutive individuals treated between March 2015 and June 2018 with curved osseointegration femur implant (OFI-C) indicated for a long femoral remnant, gamma osseointegration femur implant (OFI-Y) indicated for a short femoral remnant, or osseointegration tibia implant (OTI) were eligible for this study. All adverse events were evaluated, infections were graded as follows: grade 1 and 2: low- and high-grade soft tissue infection, respectively, grade 3: deep bone infection, grade 4: septic implant failure. Functional outcome measures included prosthesis wearing time (PUS), health-related quality of life (GS), and the overall situation as an amputee (GS Q3); evaluated with the Questionnaire of persons with trans-femoral amputation (Q-TFA) before surgery and at one-year follow-up.

RESULTS

Ninety of 91 individuals were included (mean age: 54±14 yrs, 26 females); treated with 53, 16 and 21 OFI-C, OFI-Y and OTI, respectively. Soft tissue infections (grade 1: 11 events, grade 2: 10 events) were treated successfully with antibiotics except in two (OFI-C and OFI-Y), who required additional surgery due to recurrent stoma irritation and peri-stoma abscess drainage. One individual with dysvascular amputation (OTI) developed septic implant loosening and occlusion of the femoral artery resulting in a transfemoral amputation. No aseptic loosening's occurred. One individual (OFI-Y) required stoma surgical refashioning due to soft tissue redundancy. At baseline mean ±SD and median (25th to 75th PCTL) Q-TFA PUS and GS were 52±39, 52(7-90) and 40±19, 42(25-50) and improved significantly to 88±18, 90 (90-100) and 71±15, 75 (67-83) at one-year follow-up. The GS Q3 improved over time.

CONCLUSION

Titanium osseointegration implants can be safely used within a one-year follow-up period. The performance improved compared to the use of a socket-suspended prosthesis.

[Pseudoaneurysm of the uterine artery: apropos of 1 case]

Pseudoaneurism of the uterine artery is uncommon and is usually associated with pregnancy or surgical trauma. Diagnosis is based on both Doppler sonography and arteriography. We report a case of pseudoaneurysm of the uterine artery associated with a leiomyoma without prior surgery or pregnancy. Treatment, which consisted on laparotomy, allowed avoiding rupture and confirmed diagnosis.

Hard metal exposures. Part 2: Prospective exposure assessment

Hard metal exposures may precipitate lung disease in exposed workers. This article reports on a project investigating the relationship between local exhaust hood air flow levels and workplace hard metal exposures. Airborne cobalt, chromium, and cadmium exposure concentrations, and ventilation system function were monitored for three consecutive days prior to installation of three new ventilation systems, and then were followed monthly for one year. Work activities included wet and dry grinding of saw blades, brazing, welding, and setup. Work task exposures were highly variable over the period of the study. Ventilation air flows failed to meet design goals due to low total air volume and poor distribution; however, worker exposures to metals were controlled in most cases. Hood design, worker acceptance, and use of the hoods were as important in controlling exposures as were exhaust hood air flow levels.

[Testicular microlithiasis]

Testicular microlithiasis is an uncommon condition in which calcified concretions fill the lamina of seminiferous tubules. It has a specific appearance on sonography with diffuse intra testicular echogenic foci without acoustic shadows. Testicular microlithiasis can be associated with various entities and frequently with primary testicular neoplasm. The authors report a new case of testicular microlithiasis diagnosed by sonography in a 14-year-old boy with epididymo-orchitis. Based on a review and discussion of the literature, the authors emphasize the importance of regular and protracted ultrasound follow-up and monitoring of serum tumour markers to allow early detection of primary testicular neoplasm.

[Attempted classification of scrotal contusions]

We present a review of the literature and results of a survey involving 50 closed scrotal traumas. Based on this analysis, we propose an anatomoclinical classification of scrotal contusions based on what we consider to be the most appropriate therapeutic management.

[Treatment of kidney and retroperitoneal abscesses using percutaneous drainage. Apropos of 17 cases]

For a long time, the treatment of retroperitoneal abscesses was exclusively surgical. Ultrasonography and computed tomography provide new therapeutic approaches to these lesions. The authors report a series of 17 renal and retroperitoneal abscesses treated by primary percutaneous drainage. This treatment generally ensures a favourable course, avoiding the need for surgery, which is still indicated in patients with associated uropathy or after failure of percutaneous drainage.

[Ultrasonographic aspects of kidney pelvis tumors associated with infectious hydronephrosis of lithiasic origin]

The ultrasonographic findings of 4 patients with surgically confirmed urothelial tumors associated with calculic pyonephrosis are presented. All the involved were markedly enlarged and hydronephrotic with obstructive calculi, stigmata of pyonephrosis and, an echoic pelvic mass, extending in calyceas in 2 cases. The sonographic appearance correlated well with the gross pathological findings. The histological types were 2 squamous cell carcinomas, 1 adeno-squamous cell carcinoma and 1 transitional carcinoma. The chronic calculic irritation was proved to induce squamous and glandular metaplasia. The subsequent squamous carcinoma and adenocarcinoma were documented in the literature. The preoperative diagnosis of the associated tumor was rarely done. The sonographic features reported are highly suggestive of urothelial tumor and may lead to an accurate preoperative diagnosis.

[The "blue rubber bleb nevus" (Bean's syndrome): uncommon cause of gastrointestinal bleeding]

A ten year old boy had six cutaneous angiomas and recurrent rectal bleeding responsible for iron deficiency anemia. Histological examination established the diagnosis of blue rubber bleb naevus syndrome. Endoscopy, arteriography, computed tomography, and angioscintigraphy disclosed additional angiomas in the stomach and rectum and along the blood vessels in the lower limbs. The value of angioscintigraphy for identifying angiomas escaping detection by other means was illustrated in this case. Embolization of the inferior mesenteric artery was successful in preventing further rectal bleeding. Treatment of this disorder remains controversial.

Cobalt exposure in a carbide tip grinding process

Reports relating hard metal disease or nonspecific respiratory symptoms to tungsten or cobalt exposure have been published in the past 20 yr. This report discusses a work site investigation of a small company, employing approximately 50 workers, producing carbide tip saw blades for the woodworking industry. Cobalt exposure was characterized by ambient air monitoring (area and personnel), particle size determination, and biological monitoring. Area sampling for cadmium, cobalt, and tungsten indicated low ambient air levels in all manufacturing areas except the grinding department, which had cobalt air levels approaching the threshold limit value of 0.05 mg/m3. Area airborne cobalt exposure levels measured over six shifts in the grinding department ranged from 0.017 to 0.12 mg/m3 for the total collection method and 0.002 to 0.028 mg/m3 for the method collecting respirable particles. Cobalt content in the total and respirable fractions was similar. Urine monitoring indicated production workers have elevated cobalt levels, and the grinders' levels were higher than other production workers. The grinding coolant was found to have elevated cobalt concentrations. A survey of coolants from nine carbide grinding shops indicated the elevated cobalt concentrations may be common.

[Chemoembolization of malignant liver tumors]

The main aspects of hepatic chemoembolization are first described: principles, drugs and their vectors, various techniques and contra-indications. In the literature as in our own experience, most encouraging results are reported in metastases from endocrine tumors and hepatocellular carcinoma. Favourable results in the latter disease have been particularly emphasized by Japanese authors whose data are reported, as well as results in a personal series and in three controlled studies. Chemoembolization is now able to induce partial or complete responses. Nevertheless, unambiguous selection of responding patients cannot be stated yet, especially for hepatocellular carcinoma where an underlying chronic liver disease probably plays an important role in prognosis. Consequently, chemoembolization of malignant hepatic tumors must still be considered as a technique under evaluation.

[Thrombophlebitis of the ovarian vein. Apropos of 2 cases]

Thrombophlebitis of the ovarian vein is a rare post-partum complication. Its diagnosis is said to be difficult, but was greatly facilitated by the progress made in imaging. The authors report about two cases identified with computed tomography. Evolution was favorable in both cases with an anticoagulant and antibiotic treatment.

[Contribution of imaging in complications of colo-anal anastomoses. Apropos of 61 cases]

The authors studied the complications occurring in 61 cases of colo-anal anastomosis carried out for cancer in 55 cases. Fistula formation occurred in 14 cases i.e. approximately 23%. This was symptomatic in 11 cases i.e. 18%. Their clinical course was favourable. One case of necrosis of the reservoir was seen. The recurrence rate for neoplasms was 14.3% and was no higher than after abdomino-perineal resection. The procedure is justified in terms of tumour recurrence.