OUP accepted manuscript

Background

Blood biomarkers have the potential to help identify COVID-19 patients with bacterial coinfection in whom antibiotics are indicated. During the COVID-19 pandemic, procalcitonin testing was widely introduced at hospitals in the UK to guide antibiotic prescribing. We have determined the impact of this on hospital-level antibiotic consumption.

Methods

We conducted a retrospective, controlled interrupted time series analysis of organization-level data describing antibiotic dispensing, hospital activity and procalcitonin testing for acute hospitals/hospital trusts in England and Wales during the first wave of COVID-19 (24 February to 5 July 2020).

Results

In the main analysis of 105 hospitals in England, introduction of procalcitonin testing in emergency departments/acute medical admission units was associated with a statistically significant decrease in total antibiotic use of −1.08 (95% CI: −1.81 to −0.36) DDDs of antibiotic per admission per week per trust. This effect was then lost at a rate of 0.05 (95% CI: 0.02–0.08) DDDs per admission per week. Similar results were found specifically for first-line antibiotics for community-acquired pneumonia and for COVID-19 admissions rather than all admissions. Introduction of procalcitonin in the ICU setting was not associated with any significant change in antibiotic use.

Conclusions

At hospitals where procalcitonin testing was introduced in emergency departments/acute medical units this was associated with an initial, but unsustained, reduction in antibiotic use. Further research should establish the patient-level impact of procalcitonin testing in this population and understand its potential for clinical effectiveness.

Factors Affecting Predictability of Buccal Bone Augmentation in Surgically Facilitated Orthodontic Treatment: Surgical Considerations

The purpose of surgically facilitated orthodontic treatment (SFOT) is to increase and thicken the periodontal biotype, including both hard and soft tissue, and facilitate accelerated tooth movement through the induction of the regional acceleratory phenomenon. This article discusses the surgical and biomaterial factors related to increased predictability of bone augmentation when performing this pre-orthodontic surgical technique. Critical surgery-related factors of SFOT that will be examined include incision and flap design and closure, the depth and location of corticotomies, surgical trauma, augmentation protocols, and postoperative considerations. Biomaterial-related factors that will be reviewed encompass bone grafting materials, biologics, barrier membranes, and planned tooth movement.

Surgical Considerations and Decision Making in Surgically Facilitated Orthodontic Treatment/Periodontally Accelerated Osteogenic Orthodontics

FOCUSED CLINICAL QUESTION

Surgically facilitated orthodontic treatment (SFOT)/periodontally accelerated osteogenic orthodontics (PAOO) has the potential of allowing safer orthodontic treatment in vulnerable periodontium with thin phenotypes. SFOT/PAOO is a phenotype modification therapy (PhMT) approach where thin bone morphotype and/or gingiva are surgically augmented to convert a fragile-thin to a robust-thick periodontal environment. This permits orthodontic treatment in these previously thin phenotype cases to proceed without iatrogenically-induced adverse effects. This is an infrequently performed procedure with few available clinical recommendations.

SUMMARY

In this practical application paper, three clinicians with the collective clinical experience of over 1500 SFOT cases developed a clinical decision-making algorithm outlining the key steps for SFOT. A sample case is provided for clinical appreciation of the procedure. Lastly, this panel reviewed and detailed the critical decision making and surgical approaches associated with the use of SFOT. Though the basic decision making is consistent, individual variations on surgical management are compared. This is summarized in a clinical decision tree along with a sample clinical case. Additionally, the cumulative experience has been organized into tables that provide comparative decision and surgical approaches. There are similarities and differences. Lastly, strategies that have not been individually effective are also noted.

CONCLUSION

SFOT/PAOO is an effective PhMT approach whereby the bone and/or soft tissue phenotype can be surgically modified to permit orthodontic treatment in patients with thin phenotypes. The cumulative experience of three experienced clinicians provides clinical recommendations for SFOT management of PhMT for pre-orthodontic treatment.

Is gingival recession a consequence of an orthodontic tooth size and/or tooth position discrepancy? "A paradigm shift"

BACKGROUND

Gingival recession (GR) is a commonly observed dental lesion. The underlying etiology has not been clearly identified, although several theories have been suggested. Tooth crowding or tooth malalignment is also frequently observed, with both conditions appearing to be more prevalent in developed countries with heterogeneous populations.

MATERIALS AND METHODS

A total of 25 consecutively treated patients representing 72 teeth and demonstrating facial clinical GR of > 3 mm were examined clinically, photographically, and with 3-dimensional radiology using cone-beam computed tomography. All examined teeth presented with normal interproximal probing depths and attachment levels (less than 4 mm). Tooth position or tooth volume plus the associated adjacent alveolar bone volume and GR were analyzed. This group was further evaluated during periodontal surgery for associated alveolar bone fenestrations or dehiscences.

RESULTS

All teeth demonstrating > 3 mm of GR presented with significantly prominent facial tooth contours and associated alveolar bone dehiscences. Most involved teeth presented with their root structures extending beyond the facial alveolar bony housing (fenestrations). This represents a discrepancy between tooth size and alveolar bone dimensions in the buccolingual, axial, and sagittal orientation. Fewer involved teeth were malpositioned toward the buccal aspect. Both conditions were associated with facial alveolar bone dehiscences and associated GR.

CONCLUSIONS

This study suggests tooth volume and/or tooth position within the alveolar bony housing strongly correlate with GR. All nonperiodontitis-involved teeth with GR were associated with either wider teeth or facially aligned teeth. However, it is emphasized that all facially aligned teeth, or "larger" teeth, do not necessarily present with GR. Based on these findings, the radiographic-supporting bone index is proposed. This index should facilitate appropriate evaluation of the alveolar bone supporting the mucogingival complex, both on the facial and lingual aspect of teeth. Further investigations are needed to support these preliminary data.

Is gingival recession a consequence of an orthodontic tooth size and/or tooth position discrepancy? "A paradigm shift"

BACKGROUND

Gingival recession (GR) is a commonly observed dental lesion. The underlying etiology has not been clearly identified, although several theories have been suggested. Tooth crowding or tooth malalignment is also frequently observed, with both conditions appearing to be more prevalent in developed countries with heterogeneous populations.

MATERIALS AND METHODS

A total of 25 consecutively treated patients representing 72 teeth and demonstrating facial clinical GR of > 3 mm were examined clinically, photographically, and with 3-dimensional radiology using conebeam computed tomography. All examined teeth presented with normal interproximal probing depths and attachment levels (< 4 mm). Tooth position or tooth volume plus the associated adjacent alveolar bone volume and GR were analyzed. This group was further evaluated during periodontal surgery for associated alveolar bone fenestrations or dehiscences.

RESULTS

All teeth demonstrating > 3 mm of GR presented with significantly prominent facial tooth contours and associated alveolar bone dehiscences. Most involved teeth presented with their root structures extending beyond the facial alveolar bony housing (fenestrations). This represents a discrepancy between tooth size and alveolar bone dimensions in the buccolingual, axial, and sagittal orientation. Fewer involved teeth were malpositioned toward the buccal aspect. Both conditions were associated with facial alveolar bone dehiscences and associated GR.

CONCLUSIONS

This study suggests tooth volume and/or tooth position within the alveolar bony housing strongly correlate with GR. All nonperiodontitis-involved teeth with GR were associated with either wider teeth or facially aligned teeth. However, it is emphasized that all facially aligned teeth, or "larger" teeth, do not necessarily present with GR. Based on these findings, the radiographic-supporting bone index is proposed. This index should facilitate appropriate evaluation of the alveolar bone supporting the mucogingival complex, both on the facial and lingual aspect of teeth. Further investigations are needed to support these preliminary data.

Filgrastim treatment of acute myelogenous leukemia (M7) relapse after allogeneic peripheral stem cell transplantation resulting in both graft-versus-leukemia effect with cytogenetic remission and chronic graft-versus-host disease manifesting as polyserositis and subsequent bronchiolitis obliterans with organizing pneumonia

Filgrastim (granulocyte colony-stimulating factor) has recently been reported to successfully treat patients with leukemic relapse after allogeneic peripheral stem cell transplantation (PSCT). However, the majority of the patients who responded also developed graft-versus-host disease (GVHD). Polyserositis as a manifestation of GVHD is a rare phenomenon. We report the first case of polyserositis following the use of filgrastim to treat a patient with acute myelogenous leukemia (M7), who had relapsed after an initially successful allogeneic PSCT. The polyserositis manifested with effusions and was initially controlled with high doses of steroids and pericardial stripping; however, after a quiescent period the patient eventually developed bronchiolitis obliterans with organizing pneumonia that required additional immunosuppressive therapy. We review the literature on GVHD-associated polyserositis and offer potential explanations for its pathogenesis.

Systemic administration of insulin-like growth factor (IGF)-binding protein-4 (IGFBP-4) increases bone formation parameters in mice by increasing IGF bioavailability via an IGFBP-4 protease-dependent mechanism

Insulin-like growth factor (IGF)-binding protein-4 (IGFBP-4) is a potent inhibitor of IGF actions in vitro. However, we found that systemic administration of IGFBP-4 at pharmacological doses caused a significant increase in bone formation parameters in mice by a mechanism that may involve increased IGF bioavailability via proteolysis of IGFBP-4. To evaluate the hypothesis that proteolysis of IGFBP-4 is essential for the stimulatory effects of systemically administered IGFBP-4, we produced wild-type, protease-resistant, and IGFBP-4 proteolytic fragments and evaluated their effects using biochemical markers. Protease-resistant IGFBP-4 was more potent than wild-type IGFBP-4 in inhibiting IGF-I-induced mouse osteoblast cell proliferation in vitro and in inhibiting IGF-I-induced increase in alkaline phosphatase (ALP) activity in bone extract after local administration in vivo. Systemic administration of wild-type IGFBP-4, but not protease-resistant IGFBP-4, increased serum osteocalcin, serum ALP, and ALP in skeletal extracts in a dose-dependent manner, with a maximal effect of 40% (P < 0.05) at 1.25 nmol/mouse. Systemic administration of wild-type, but not protease-resistant, IGFBP-4 increased free IGF-I levels in serum in normal mice. IGF-I, but not wild-type IGFBP-4, increased bone formation parameters in IGF-I-deficient mice. This study demonstrates that systemic administration of IGFBP-4 increases bone formation parameters in mice by increasing IGF bioavailability in the circulation via an IGFBP-4 protease-dependent mechanism.

Prospective evaluation of cancer clinical trial accrual patterns: identifying potential barriers to enrollment

PURPOSE

Well-conducted cancer clinical trials are essential for improving patient outcomes. Unfortunately, only 3% of new cancer patients participate in clinical trials. Barriers to patient accrual in cancer clinical trials must be identified and overcome to increase patient participation.

MATERIALS AND METHODS

We prospectively tracked factors that potentially affected patient accrual into cancer clinical trials at the University of California Davis Cancer Center. Oncologists seeing new outpatients were asked to complete questionnaires regarding patient characteristics and the physician's decision-making on patient eligibility, protocol availability, and patient opinions on participation. Statistical analysis was performed to correlate these parameters with subsequent protocol accrual.

RESULTS

There were 276 assessable patients. At the initial visits, physicians did not consider clinical trials in 38% (105/276) of patients principally because of a perception of protocol unavailability and poor performance status. Physicians considered 62% (171/276) of patients for participation in clinical trials. Of these, only 53% (91/171) had an appropriate protocol available for site and stage of disease. Seventy-six of 90 patients (84%) with available protocols met eligibility criteria for a particular study. Only 39 of 76 patients (51%) agreed to participate in cancer clinical trials, for an overall accrual rate of 14% (39/276). The remainder (37/76, 49%) declined trial participation despite meeting eligibility criteria. The most common reasons were a desire for other treatment (34%), distance from the cancer center (13%), patient refusal to disclose reason (11%), and insurance denial (8%). Patients with private insurance were less likely to enroll in clinical trials compared to those with government-funded insurance (OR, 0.34; P =.03; 95% CI, 0.13 to 0.9).

CONCLUSION

Barriers to cancer clinical trial accrual can be prospectively identified and addressed in the development and conduct of future studies, which may potentially lead to more robust clinical trials enrollment. Investigation of patient perceptions regarding the clinical trials process and the role of third party-payers is warranted.

Postnatal and pubertal skeletal changes contribute predominantly to the differences in peak bone density between C3H/HeJ and C57BL/6J mice

Previous studies have shown that 60-70% of variance in peak bone density is determined genetically. The higher the peak bone density, the less likely an individual is to eventually develop osteoporosis. Therefore, the amount of bone accrued during postnatal and pubertal growth is an important determining factor in the development of osteoporosis. We evaluated the contribution of skeletal changes before, during, and after puberty to the development of peak bone density in C3H/HeJ (C3H) and C57BL/6J (B6) mice. Volumetric bone density and geometric parameters at the middiaphysis of femora were measured by peripheral quantitative computed tomography (pQCT) from days 7 to 56. Additionally, biochemical markers of bone remodeling in serum and bone extracts were quantified. Both B6 and C3H mice showed similar body and femoral weights. B6 mice had greater middiaphyseal total bone area and thinner cortices than did C3H mice. Within strains, males had thicker cortices than did females. C3H mice accumulated more minerals throughout the study, with the most rapid accumulation occurring postnatally (days 7-23) and during pubertal maturation (days 23-31). C3H mice had higher volumetric bone density as early as day 7, compared with B6 mice. Higher serum insulin-like growth factor I (IGF-I) was present in C3H mice postnatally at day 7 and day 14. Until day 31, B6 male and female mice had significantly higher serum osteocalcin than C3H male and female mice, respectively. Alkaline phosphatase (ALP) was found to be significantly higher in the bone extract of C3H mice compared with B6 mice at day 14. These data are consistent with and support the hypothesis that the greater amount of bone accrued during postnatal and pubertal growth in C3H mice compared with B6 mice may be caused by increased cortical thickness, increased endosteal bone formation, and decreased endosteal bone resorption.

Evidence that IGF-binding protein-5 functions as a growth factor

Recent studies support the concept that IGF-binding protein-5 (IGFBP-5) stimulates bone formation, at least in part, via IGF-independent mechanisms. To evaluate this hypothesis further, we evaluated in vitro and in vivo effects of IGFBP-5 on bone formation parameters using the IGF-I knockout (KO) mouse. Treatment of serum-free cultures of osteoblast clones derived from IGF-I KO mice with recombinant human IGFBP-5 increased both proliferation and alkaline phosphatase (ALP) activity in a dose-dependent manner, an effect comparable to that seen with IGF-I. IGF-II levels from media conditioned by osteoblasts derived from IGF-I KO mouse were below those detectable by RIA. To eliminate possible actions of IGF-II, if any was produced by osteoblasts derived from IGF-I knockout mice, the IGFBP-5 effect was studied in the presence of exogenously added IGFBP-4, a potent inhibitor of IGF-II actions in bone cells. Addition of IGFBP-4 blocked IGF-I- but not IGFBP-5-induced cell proliferation in osteoblasts derived from IGF-I knockout mice. Consistent with in vitro results, a single local injection of IGFBP-5 to the outer periosteum of the parietal bone of IGF-I KO mice increased ALP activity and osteocalcin levels of calvarial bone extracts. The magnitudes of IGFBP-5-induced increases in ALP and osteocalcin in parietal bone extracts of IGF-I KO mice were comparable to those seen in C3H mice. In contrast to IGFBP-5, local administration of IGFBP-4 had no significant effect on bone formation in C3H and IGF-I KO mice. These results provide the first direct evidence to our knowledge that IGFBP-5 functions as a growth factor that stimulates its actions in part via an IGF-independent mechanism.

Effects of recombinant insulin-like growth factor-binding protein-4 on bone formation parameters in mice

Insulin-like growth factor (IGF)-binding protein-4 (IGFBP-4), one of the most abundant IGFBPs produced by bone cells, is a potent inhibitor of IGF actions in vitro. To evaluate the modulation of IGF actions on bone formation in vivo by IGFBP-4, we produced intact and fragment (50- to 100-fold reduced IGF affinity) forms of BP-4 and examined their local and systemic effects using biochemical markers. Local administration of IGF-I over the right parietal bone significantly increased bone extract alkaline phosphatase activity; this was completely blocked by an equimolar dose of intact IGFBP-4, but not IGFBP-4 fragment. A single sc administration of IGF-I (2 microg/g BW) significantly increased bone formation markers in both serum and skeletal extracts; surprisingly, so did intact IGFBP-4, but not fragment IGFBP-4. Subcutaneous administration of an equimolar dose of IGFBP-4 along with IGF-I did not significantly block the IGF-I effect. Administration of intact IGFBP-4 significantly increased the serum 50-kDa IGF pool and decreased the 150-kDa IGF pool without significantly changing total IGF-I. We postulate that the increase in the 50-kDa IGF pool might enhance IGFs bioavailability via a mechanism involving IGFBP-4-specific protease. This study demonstrates for the first time that a single local administration of IGFBP-4 inhibits IGF-I-induced increases in bone formation, whereas systemic administration of IGFBP-4 alone increases serum levels of bone formation markers.

Recombinant human insulin-like growth factor-binding protein-5 stimulates bone formation parameters in vitro and in vivo

Insulin-like growth factor-binding protein-5 (rhIGFBP-5) is stored in bone and stimulates osteoblast cell proliferation in vitro. Bone formation is dependent on the number and activity of osteoblasts. We therefore evaluated the ability of recombinant human (rh) IGFBP-5 to increase osteoblast activity in vitro; both alkaline phosphatase (ALP) activity and osteocalcin levels showed a dose-dependent increase. In in vivo time-course studies, daily s.c. administration of 50 microg rhIGFBP-5/day/mouse significantly increased serum osteocalcin levels by day 7, and these levels were sustained through day 21. We further evaluated whether rhIGFBP-5 was as effective as IGF-I. Daily s.c. administration of rhIGFBP-5 (50 microg/day), IGF-I (13 microg/day), or IGF-I plus rhIGFBP-5 complex for 9 days increased serum osteocalcin levels by 58%, 65%, and 81% (P < 0.001 in all) and femoral bone extract ALP activity by 85% (P < 0.001), 29% (P < 0.05), and 13% (P = NS), respectively, and decreased carboxyl-terminal cross-linked telopeptide of type I collagen by 29% (P < 0.05), 20% (P = NS), and 12.5% (P = NS), respectively. One s.c. injection of rhIGFBP-5 (50 microg/mouse) increased serum osteocalcin and bone ALP activity by 21% (P < 0.05) and 27% (P < 0.02), respectively, after 5 days, but did not significantly increase serum IGF-I (1, 6, or 24 h/postinjection), suggesting that the effects of rhIGFBP-5 on bone are not mediated by increasing circulating IGF-I. Our data demonstrate that systemic administration of rhIGFBP-5, either alone or in combination with IGF-I, increases bone formation parameters in vivo.

Prevention of hypermenorrhea with leuprolide in premenopausal women undergoing bone marrow transplantation

We report on the use of leuprolide to prevent heavy menstrual bleeding that often occurs before platelet engraftment in premenopausal women undergoing bone marrow transplantation (BMT). Leuprolide, a synthetic analog of gonadotropin-releasing hormone (Gn-RH-a), was given to 34 patients by intravenous bolus injection, 1 mg daily, until platelet recovery. The median duration of therapy was 50 days (range 16-170). When necessary, patients self-administered the drug after discharge from the hospital. No adverse effects could be related directly to the use of leuprolide. Leuprolide effectively prevented menstruation in 25 patients (73%), failed in seven (21%), and two patients were not evaluable. The success of leuprolide therapy was related to the time of onset of treatment, as anticipated from the gradual effect of Gn-RH-a on the menstrual cycle. The failure rate was only 6% (one of 16 patients) when leuprolide was started at least 2 weeks prior to the development of thrombocytopenia, compared to a failure rate of 33% (six of 18 patients) when leuprolide was started at a later time. We conclude that leuprolide as a single agent is a safe and effective method to prevent menstrual bleeding during BMT. Additional studies are needed to determine the best timing for the onset of therapy and the relative benefit of leuprolide compared to other prophylactic approaches in patients with lengthy thrombocytopenia.

Peripheral blood stem cell transplantation: Impact on procedure load and workload in an apheresis unit

Peripheral blood stem cells (PBSC) reinfusion appears to hasten hematologic reconstitution following myeloablative therapy. While procurement of PBSC adds apheresis procedures, rapid engraftment could decrease the demand for platelet transfusions. To determine the impact of PBSC collection on workload in our apheresis unit, we studied 3 consecutive groups of patients with metastatic breast cancer given comparable high-dose chemotherapy and autologous bone marrow transplant, with or without PBSC or granulocyte-colony stimulating factor (G-CSF). Forty-one transplants were performed with bone marrow cells only: 31 patients (Group A) did not receive G-CSF, while the following 10 patients (group B) received daily G-CSF until neutrophil engraftment. Bone marrow cells and PBSC were used for the most recent 11 transplants (group C), followed by daily G-CSF until engraftment. PBSC were mobilized with cyclophosphamide (4 g/m2) and etoposide (1 g/m2), followed by G-CSF, 8 micrograms/kg/day. PBSC collection was carried out on a Fenwal CS3000+ cell collector, using modified procedure 1, to obtain a minimum of 5 x 10(8) mononuclear cells/kg. The times to neutrophil count over 500/microL, platelet count over 20,000/microL, and discharge from the hospital after transplant were significantly shorter for patients in group C (medians of 8, 8, and 21 days, respectively) compared to group A (medians of 14, 14, and 29 days; P = 0.001) or group B (medians of 11, 24, and 32 days; P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of myeloid blastic crisis of chronic myelogenous leukemia

Patients with myeloid blastic crisis of chronic myelogenous leukemia were treated by chemotherapy or by autologous hematopoietic reconstitution after aggressive chemotherapy. Chemotherapy alone failed to produce a second chronic phase. Autologous transplantation resulted in the establishment of a second chronic phase in two of ten patients treated with a four-drug regimen, while treatment with high-dose cytarabine with or without busulfan resulted in the establishment of a second chronic phase in three of six patients and the return of normal hematopoiesis in a fourth. Consolidation chemotherapy appeared to be beneficial.

The physics of cancer therapy with negative pions

The introduction of negative pions into cancer therapy has required the construction of large new proton accelerators together with special magnetic systems to form and direct the pion beam to a patient. A summary is presented of the fundamental properties of pions and of the methods used to study the therapeutic beams. The dosimetry of these beams requires the use of the older techniques as well as new methods for determining the different LET components. The data for a number of beams is given and the utilization of this data in treatment planning is reviewed. An important problem for therapy is the behavior of inhomogeneities in the pion beam, and experimental methods are described which illuminate this problem. The studies of the effects of inhomogeneities in a beam point the way toward fruitful comparisons with the computerized treatment planning codes known as PION-1 and PIPLAN. A useful step in treatment is the verification of doses in patients during therapy. For this purpose the new methods for measuring the high LET doses in patients are described as well as a timing measurement for checking the stopping effect of the tissues as obtained from the CT scans.

The three dose components of negative pion beam and their role in pion radiotherapy

A new method has been developed for analyzing therapeutic negative pion beams into three LET (linear energy transfer) dose components inherent in such a beam. The technique utilizes thin silicon detectors to obtain pulse height spectra produced by the various particles in the beam traversing the detectors. It is shown that a low LET group is correlated with the incoming pions, muons and electrons; a medium LET group corresponds to protons, deuterons, tritons, and high energy alpha particles; and a high LET group is due to low energy alpha particles, 3He and recoil particles. Several beams used clinically have been studied.

An automated dosimetry data-acquisition and analysis system at the LAMPF pion therapy facility

An automated data-acquisition and analysis system has been developed for dosimetry measurements on the pion therapy beam at the Clinton P. Anderson Meson Physics Facility Biomedical Channel in Los Alamos using a PDP-11/45 computer and CAMAC interface. Initialization, test, and monitor programs allow the user to set the physical limits of scanner travel, test the data lines, calibrate the analog signals for the scanner position, and monitor the analog versus digital values of the scanner position during operation. Data-acquisition programs scan beams in one, two, and three dimensions. Many options are available to the user in selecting the scan parameters and in changing some of these parameters during scanning. Data-analysis programs provide reproduction of stored data, comparison of linear scans, beam profiles along any line of a planar or volume scan, and isodose distributions from any planar scan or from any planar scan or from any plane of a volume scan. Other programs summarize stored data files and search for specific data according to the user's instruments.

Characteristics of a negative pion beam in a therapeutic application

Lithium-drifted silicon detectors were used to investigate the components of the pion beam at the Los Alamos Meson Physics Facility. The components of the incoming beam are about 5% electrons, 10% muons, and 85% pions. Pulse spectra of the incoming beam and of the "stars" produced by the pions were obtained in a phantom. The analysis of the spectra into different LET components showing where pions are most effective is presented.