Impact of hypothermia alert device (BEMPU) on improvement of duration of Kangaroo Mother Care (KMC) provided at home: parallel-group randomized control trial

The objective of the study was to determine if using the hypothermia-detecting bracelet (named BEMPU) improves the duration of Kangaroo Mother Care (KMC) at home by one hour. This parallel-group randomized controlled trial was conducted at a step-down nursery of a teaching hospital. Neonates between 1000 and 2000 g were randomized to BEMPU and control groups at the time of discharge. BEMPU was applied at the wrist of each newborn in the BEMPU (intervention) group. Parents were advised to keep the BEMPU in place till 4 weeks post-discharge. The BEMPU generates a beep sound as an alarm when a newborn's temperature drops below 36.5 °C. Parents in both groups were trained to provide KMC at home. Parents in the BEMPU group received the "KMC chart" and "BEMPU beep chart," while the control group received the "KMC chart" only. In the "KMC chart," parents entered information about KMC hours on a real-time basis, and in the "BEMPU beep chart," they entered information about alarm beeps from BEMPU on a real-time basis till 4 weeks post-discharge. Independent samples t-test was used to compare mean KMC hours between the two groups. A total of 128 neonates participated in the study (64 in BEMPU and 64 in Control groups). The mean(SD) gestational age for the BEMPU group was 34.04(2.84) weeks vs 34.75(2.70) weeks for the control group. In BEMPU group, mean(SD) daily time spent doing KMC was significantly higher in 1st week [4.78(2.93) vs. 3.22(2.44) h, p = 0.003], in 2nd week [4.52(3.43) vs. 2.84(2.95) h, p = 0.008], in 3rd week [4.23(3.71) vs. 2.30(2.70) h, p = 0.003], in 4th week [3.72(3.30) vs. 1.95(2.65) h, p = 0.003] as compared to control group. BEMPU improved the daily duration of KMC hours at home compared to the control group over four weeks. Clinical Trial Registration: This trial is registered at Clinical Trials Registry India with registration number: CTRI/2018/08/015154 and accessible at http://ctri.nic.in/Clinicaltrials/pdf_generate.php?trialid=27600&EncHid=&modid=&compid=%27,%2727600det%27 Registered on 01/08/2018.

Reducing False Alarms and Alarm Fatigue from Pulse Oximeters in a Neonatal Care Unit: A Quality Improvement Study

Background:

Pulse oximeters play a vital role in monitoring sick newborns, but majority of the times, their alarms are of little clinical significance. False alarms from pulse oximeters were frequent in our neonatal intensive care unit, causing desensitization of staff and inattention to clinically important alarms.

Objectives:

The objective of the study was to reduce the burden of false alarms and alarm fatigue.

Methods:

This was a quality improvement (QI) study. During the baseline phase, alarms for heart rate and SPO2 (percentage of oxygenated blood) were evaluated. Response to them within 30 s was checked. Major causes of false alarms were the movement of the newborns, inappropriate alarm limits, and loose probe. Fishbone chart was prepared, and Plan-Do-Study-Act (PDSA) model was designed using point of care quality improvement (POCQI) principles. During the first PDSA (implementation phase), the staff was trained to adjust alarm limits using the reference chart. A lecture on noise hazards, emphasis on muting the alarms, and advice to change probe site at beginning of their duty was given. In the second PDSA (sustenance phase), components of the first PDSA were strengthened by supportive supervision and guidance and the training of new staff.

Results:

Total 494, 329, and 162 alarms were observed during baseline, implementation, and sustenance phases, respectively. In the baseline phase majority, 364 (73.7%) were false alarms, which occurred at a frequency of 0.39 alarms/patient/h. More than one-third of the alarms were not responded timely. After QI, false alarms reduced to 214 (65%; 0.22 alarms/patient/h) and 100 (61.7%; 0.16 alarms/patient/h) in implementation and sustenance phases, respectively. Response to true alarms improved from 101 (77.7%) to 104 (90.4%) to 62 (100%) during the 3 phases consecutively.

Conclusion:

Frequent false alarms lead to desensitization of health care workers. POCQI principles can be a practical approach for reducing false alarms and improving alarm safety.

Comparison of Fenton Versus Intergrowth-21 Growth Charts for Preterm Neonates

Background:

Fenton charts from developed world are commonly used for growth assessment of preterm newborns. Recently prescribed Intergrowth-21 (IG-21) charts look more promising as they include mixed population from economically diverse nations.

Objective:

We compared IG-21 with Fenton charts for birth size classification and extrauterine growth in preterm infants.

Study design:

A prospective collection of growth parameters.

Participants:

Preterm newborns (<37 weeks).

Intervention:

Weight (W), length (L), and head circumference (HC) were collected at weekly interval during the stay as well as follow-up.

Outcomes:

Growth of preterm newborns at birth and last follow-up was assessed using Fenton and IG-21 charts. Agreement between Fenton and IG-21 for percentiles and z-scores of growth parameters was assessed using Bland-Altman plot.

Results:

A total of 301 preterm newborns were enrolled in the study. Mean (standard deviation [SD]) gestational age at birth was 34.08 (1.84) weeks, while at last follow-up (N = 296) it was 37.62 (1.85) weeks. The mean (SD) of birth W, L, and HC were 1889.24 (418.9) g, 44.69 (3.03) cm, and 30.6 (1.84) cm, respectively, while for last follow-up, they were 2114.76 (397.7) g, 47.64 (2.97) cm, and 32.65 (1.7) cm, respectively. The agreement of z-score/percentile between the 2 growth charts was not good for all the anthropometric parameters. Overall, Fenton reported more intrauterine (42.9% vs 36.9%) and extrauterine (92.9% vs 73%) growth restriction as compared to IG-21.

Conclusion:

The agreement between the 2 charts was poor. More proportions of the preterm population were growth restricted using Fenton charts.

Acute Arterial Ischemia in a Neonate: Complication of an Indwelling Radial Artery Catheter

A full-term newborn with perinatal depression, meconium stained liquor, shock, and hypoglycemic seizures was admitted at a hospital after 70 hours of life. He was ventilated, received antibiotics, and vasopressors. After 8 hours of left radial artery catheterization, ischemic changes appeared on tips of all the fingers of the newborn. The catheter was removed, and intravenous unfractionated heparin was started. Arterial Doppler revealed thrombus in both radial and ulnar arteries. The case was of category III (irreversible) acute arterial ischemia. Review Doppler after 4 days showed low resistance and dampened flow in radial and ulnar arteries. Surgical intervention was not done. Aspirin was given at discharge, and at 40 days, the distal end of the metacarpals was affected. The positive modified Allen’s test and close clinical monitoring did not guarantee the safety of radial artery catheterization. Other measures need to be critically evaluated to identify evolving thrombus early.

Clinical Profile and Outcome of Newborns with Acute Kidney Injury in a Level 3 Neonatal Unit in Western India

INTRODUCTION

Acute Kidney Injury (AKI) is a serious condition in neonatal care. It complicates the management necessitating the restrictive use of medications.

AIM

To evaluate clinical profile, identify associated and prog-nostic factors in newborns with AKI.

MATERIALS AND METHODS

This was a case control study done between January 2008 to January 2010. Total 1745 newborns were admitted, of which 74 babies had AKI. It was defined as serum creatinine >1.5mg/dl. Control group was selected randomly from the hospital numbers of the newborns derived from the electronic registry with serum creatinine below 1.5 mg/dl. Demographic variables like birth weight, gender, gestational age, admission age, growth restriction, Apgar scores, electrolyte levels; and common clinical conditions like asphyxia, sepsis, meningitis, persistent pulmonary hypertension, Necrotizing Enterocolitis (NEC), mechanical ventilation, congenital heart disease; were compared amongst the two groups. Information was obtained from the admission register, admission files, labor register of obstetrics and gynaecology department and electronic registry. Chi square/independent sample t-test as applicable and logistic regression were used to establish an association of various factors and outcome with AKI.

RESULTS

The incidence of AKI in our study was 4.24%. Demographic variables more common in AKI group were inborn (p=0.011), male gender (p=0.032), term gestation (p=0.001), Appropriate for gestational age (0.001), higher birth weight (p<0.001), full term (p<0.001), sepsis (p<0.001), NEC (p=0.042), low ApGAR scores at one minute (p=0.011) and five minute (p=0.003). However, on multivariate logistic regression only male gender [Odds Radio (OR)=2.84, Confidence Interval (CI)=1.12-7.21] and Sepsis (OR=14.46, CI=4.5-46.46) were associated with AKI. Respiratory distress syndrome was more prevalent in the control group (p<0.003). No need of mechanical ventilation and absence of shock, improved the survival.

CONCLUSIONS

AKI continues to be of clinical significance in neonatal intensive care. Further studies are needed to evaluate newer associations (like male gender and low APGAR scores).

Educational intervention to improve intravenous cannulation skills in paediatric nurses using low-fidelity simulation: Indian experience

INTRODUCTION

Inserting, monitoring and maintaining intravenous access are essential components of nursing. We evaluated simulation training on a manikin to improve cannulation skills.

METHODS

Nursing staff managing paediatric patients were asked to cannulate NITA Newborn-1800 manikin before and after appropriate training. Skills were assessed by a single assessor using an objective structured clinical examination (OSCE) checklist. Four steps were identified as critical. A score of 8/10 (80%) was considered satisfactory. Knowledge was assessed by 10 questions. A training module consisting of theoretical aspects, PowerPoint presentations, videos and hands on training over a manikin was conducted. Post-training assessment was done 1 week later.

RESULTS

Seventy-five (80.6%) nurses who completed preassessments and postassessments were assessed for paired comparisons of knowledge and skill. The majority of the nurses were females, had contractual appointment, were in their early career phase and from the paediatric wards. The mean (SD) post-training knowledge score was greater vis-a-vis pretraining score (7.52 (1.58) vs 5.32 (1.57), P<0.001). A similar result was observed for total OSCE scores (9.22 (0.66) vs 7.91 (1.11), P<0.001). Significantly higher proportion of participants exhibited intravenous cannulation satisfactorily after the training vis-a-vis pretraining assessment (69 (92%) vs 36 (48%), P<0.001).

CONCLUSION

Training using manikin showed improvement in post-training score of intravenous cannulation skill of paediatric nurses; however, this finding needs further confirmation by a randomised control trial, as our study does not have a control group.

Infant and Young Child Feeding Practices in Infants Receiving Skin to Skin Care at Birth: Follow-up of Randomized Cohort

INTRODUCTION

Skin to Skin Care (SSC) in neonatal period influences immediate breastfeeding outcomes in early childhood, especially the duration of exclusive breastfeeding.

AIM

We investigated influence of 17 hours of SSC given from day one of life on Infant and Young Child Feeding (IYCF) practices through one year of life.

MATERIALS AND METHODS

Follow-up of a Superiority Randomized Control Trial (RCT) (CTRI/2013/06/003790) conducted in a teaching hospital located in central Gujarat. Mothers of 100 neonates (48 girls, 52 boys) from previous study cohort of RCT on SSC were followed. A survey on IYCF practices during the first year of life was administered after the end of infancy. In RCT, 50 neonates had received SSC beginning of 30 min- 1 hour after birth for average 17 hours on day 1 of life. In the control group, 50 newborn were placed next to the mother and conventional care was provided. There was a significant difference between hypothermia incidences in these groups in the first two days of life.

RESULTS

There was no difference in the groups as far as the duration of exclusive breastfeeding, number of times breastfed per day, or stoppage of night feeds. No baby in either group received bottled feeds but about 53 received some form of extra lacteal feeds in the first 6 months without significant group difference. Fewer SSC mothers reported difficulties with breastfeeding or extra lacteal supplementation. All mothers who faced problems contacted physicians for advice and 20 were advised top milk and 6 given other foods. At one year of life 66% mothers were giving less than the recommended five food servings. There was no difference in practices related to hand washing, food preparation and storage, feeding habits of child and illness episodes in the children.

CONCLUSION

IYCF practices in this small group were not as per guidelines. Few positive trends were seen with fewer SSC mothers facing problems related to breastfeeding. The study was underpowered to detect differences in IYCF practices in relation to SSC.

Are Parents of Preschool Children Inclined to Give Consent for Participation in Nutritional Clinical Trials?

Objective

Micronutrient deficiencies can lead to anemia, growth restriction, and poor motor and cognitive development. A clinical trial was planned to assess the impact of nutritional supplementation on cognitive measures in preschool children. Conducting clinical trials in children is difficult due to underlying laws, hesitation of the research community, and difficult enrollment. We carried out a questionnaire-based feasibility survey to assess the interest of parents towards participation in such a nutrition-based study.

Methods

After approval from the Institutional Human Research Ethics Committee, the principals of four kindergarten schools at Vallabh Vidyanagar, Anand, Gujarat, India consented to participate. Children at the participating schools were distributed a consent form and pre-tested questionnaire, to be taken home for parents to sign, fill and return.

Results

Out of a total of 1049 consent forms and questionnaires distributed, 602 (57.39%) signed and filled forms were returned. Despite fair awareness regarding the need of research, parents’ willingness to involve their children in a 6 month duration research study, not requiring invasive measures like blood pricks, was 180 (29.9%). Nearly half (250, 41.5%) did not respond and more than a quarter (172, 28.6%) declined participation on behalf of their children.

Conclusion

The interest level of a pre-school child's parents for participation of the child in a nutrition intervention study evaluating cognitive measures like memory is low. Understanding the study population’s motivating and inhibiting factors leading to decreased participation in clinical trials is necessary to facilitate the creation of a pertinent evidence base.

Incidence of ocular side effects with intravenous zoledronate: secondary analysis of a randomized controlled trial

SUMMARY

This prospective study showed that the incidence of acute anterior uveitis, confirmed by ophthalmic examination, in patients receiving intravenous zoledronate infusions as part of a randomized controlled trial for fracture prevention is 1.1%.

INTRODUCTION

We prospectively investigated the incidence of ocular side effects after a single intravenous zoledronate infusion.

METHODS

In a secondary analysis of a double-blind, placebo-controlled trial in which early post-menopausal women (N=1054) with normal bone density or osteopenia were randomized to infusion of zoledronate 5 mg (N=703) or placebo (N=351), we analyzed significant adverse ocular events occurring within 3 months.

RESULTS

Fourteen participants reported ocular symptoms after the infusion. All were examined by an ophthalmologist and eight were diagnosed with acute anterior uveitis (AAU) and one with sectoral episcleritis. The incidence of AAU and episcleritis was 1.1% (95% CI 0.5-2.1) and 0.1% (95% CI 0.0-0.7), respectively, in the zoledronate group and 0% for both conditions in the placebo group (95% CI 0.0-0.8). The mean time from infusion to symptom onset for AAU was 3 days (range 2-4). Three cases were bilateral. AAU was mild-moderate in seven participants and severe in one. All affected eyes were treated with topical cyclopentolate 1% (to break, or minimize, posterior synechiae), and intensive, potent, topical corticosteroids with a tapering regime based on treatment response. The mean duration of topical corticosteroid was 26±10 days (range 17-44). The mean, best corrected visual acuity was 20/20 (range 20/20-20/40) at presentation, which remained unchanged after AAU resolution. None of the participants lost vision, and no long-term sequelae were reported at last follow-up (range 3-13 months post-infusion).

CONCLUSIONS

Prescribers should inform patients about the possibility of ocular side effects with zoledronate infusions and refer promptly to an ophthalmologist if symptoms develop.

Effect of early skin-to-skin contact following normal delivery on incidence of hypothermia in neonates more than 1800 g: randomized control trial

OBJECTIVE

To investigate the impact of early skin-to-skin contact (SSC) provided for first 24 h on incidence of hypothermia in stable newborns weighing 1800 g or more during first 48 h of life.

STUDY DESIGN

Stable newborns (term and late preterm: Mean gestational age 37.7 (1.35) weeks, range 34-40 weeks) having birth weight 1800 g or more (Mean weight 2605.6 (419.8) grams) were enrolled after approval from Institutional Human Research Ethics Committee (CTRI/2013/06/003790) and randomized into early SSC (intervention group) and conventional care (control group). Initial care in the delivery room for few minutes immediately after birth in both the groups was given under radiant warmer. In the intervention group, newborns were provided SSC by their mother started between 30 min and 1 h after birth for first 24 h with minimal interruption and were provided conventional care other than SSC for next 24 h of life. In the control group, newborns were kept with their mother and received conventional care other than SSC for first 48 h. Temperature and heart rate of newborns were recorded at 30 min, 1, 2, 3, 4, 5, 6, 12, 24 and at 48 h of life in both the groups. Independent Samples t-Test and relative risk were used to analyze the data.

RESULT

Both groups had 50 neonates each with similar baseline characteristics. Heart rates were in normal range in both the groups. The intervention group provided an average (s.d.) of 16.98 (0.28) h of SSC over the first 24 h period. The mean temperature was significantly high in the SSC group at all time intervals starting from 1 to 48 h (P<0.05 for all). In the SSC group only two newborns (4%) had mild hypothermia (cold stress), and, of these two newborns, one had two episodes of hypothermia. All these three episodes of hypothermia occurred within first 3 h of life. In the control group 16 newborns (32%) developed hypothermia (temperature<36.5 °C) during first 48 h of life. Of them, 11 newborns had single episode, 4 newborns had two episodes and one newborn had three episodes of hypothermia. Of these 22 hypothermic episodes, 20 occurred in the first 6 h of life and 2 episodes occurred at 48 h of life. Moderate hypothermia was seen in two newborns, whereas rest had mild hypothermia. The relative risk of developing hypothermia in the control group as compared with the SSC group was 8.00 (95% CI 1.94-32.99). There was no seasonal variation in incidence of hypothermia in both the groups.

CONCLUSION

Newborns in the SSC group achieved rapid thermal control as compared with the control group. Early SSC for 24 h after birth decreases incidence of hypothermia for initial 48 h of life. Early SSC needs to be aggressively promoted in term and late-preterm newborns to reduce incidence of hypothermia.

Tracheal Agenesis with Tracheo-oesophageal Fistula

Tracheal Agenesis (TA) presents with respiratory distress at birth. Diagnosis requires recognition of clinical signs in newborns like failure of endotracheal intubation, respiratory distress with absent air entry over both side of chest and inaudible cry. We describe a TA Floyd Type I with a Tracheo-Oesophageal Fistula (TOF) without other congenital malformations.

Tracheal Agenesis with Tracheo-oesophageal Fistula

Tracheal Agenesis (TA) presents with respiratory distress at birth. Diagnosis requires recognition of clinical signs in newborns like failure of endotracheal intubation, respiratory distress with absent air entry over both side of chest and inaudible cry. We describe a TA Floyd Type I with a Tracheo-Oesophageal Fistula (TOF) without other congenital malformations.

Near fatal case of amlodipine poisoning in an infant

An 11-mo-old infant received 12.5 times the maximum therapeutic dose of amlodipine as a result of a medication error in lieu of amoxicillin. He presented with vomiting, lethargy, breathlessness, muffled heart sounds and progressed to hypotensive shock within three hours of admission. He received mechanical ventilation, fluid therapy with normal saline and inotropes. But his parameters improved rapidly only after initiating him on insulin and dextrose infusion therapy (for 15 h) along with glucagon and calcium gluconate infusion (for 72 h). Calcium channel blockers (CCB) cause impaired insulin secretion causing hyperglycemia. High levels of blood sugar are of prognostic value rather than hemodynamic variables in CCB poisoning. A continuous infusion of 0.5 to 1 unit per kg body weight per hour of insulin along with supportive therapy including peritoneal dialysis (for deranged renal function) was used with success in managing amlodipine poisoning.

Investigation of erectile dysfunction

Erectile dysfunction (ED) represents a common and debilitating condition with a wide range of organic and non-organic causes. Physical aetiologies can be divided into disorders affecting arterial inflow, the venous occlusion mechanism or the penile structure itself. Various imaging modalities can be utilised to investigate the physical causes of ED, but penile Doppler sonography (PDS) is the most informative technique, indicated in those patients with ED who do not respond to oral pharmacological agents (e.g. phosphodiesterase type 5 inhibitors). This review will examine the anatomical and physiological basis of penile erection, the method for performing PDS and features of specific causes of ED, and will also consider the alternative imaging modalities available.

Priapism: pathophysiology and the role of the radiologist

Priapism is defined as a penile erection that persists for 4 h or longer and is unrelated to sexual activity. Its identification is important as lack of timely treatment (particularly of the low flow/ischaemic subgroup) can result in persisting erectile dysfunction as a consequence of irreversible corporal fibrosis. This review describes the physiology and anatomy of the normal erection, the aetiology and pathophysiology of the different types of priapism, and the role of the radiologist in the management of the condition. The treatment of iatrogenic priapism following intracavernosal injection of pharmacostimulant is discussed.

Transvenous embosurgery of a left sigmoid sinus dural arteriovenous fistula via a retrograde approach from the superior ophthalmic vein, cavernous and inferior petrosal sinuses

The efficacy and safety of transvenous embosurgery for sigmoid sinus dural arteriovenous fistula (DAVF) using the internal jugular vein approach is well known. Embosurgery of cavernous sinus DAVF has also been described utilizing a superior ophthalmic vein approach. The first report of a sigmoid sinus DAVF endosurgical repair via a superior ophthalmic vein approach in a patient without internal jugular vein access is presented.

Targeting CYP450 modulation to decrease the risk of induced cataract in the experimental model

Background:

Diabetes is one of the major causes of cataract. Some drugs prescribed for the treatment of diabetes are the modulators of CYP450, which may alter the risk of cataract.

Objective:

To study the effect of CYP450 modulation in galactosemic cataract.

Materials and Methods:

Male Sprague-Dawley suckling rats were allotted to four groups (n = 6), as follows: Group 1: Normal control, Group 2: Galactose control, Group 3: CYP450 inhibitor pretreated and Group 4: CYP450 inducer pretreated. Cataract was induced in animals of all groups except group 1 by feeding them galactose (50%), 21 days after parturition. From the eighteenth day of life, CYP450 inhibitor (nifedipine; 8.1 mg/kg) and CYP450 inducer (pioglitazone; 3.8 mg/kg) were given orally to groups 3 and 4, respectively. The maturation pattern of the cataract was observed by an operating microscope, every third day. Biochemical changes in the lenses of all groups, for example, CYP450 activity expressed as µM NADPH oxidized / unit time, alterations in the levels of total proteins, soluble proteins, and reduced glutathione (GSH) following the induction of cataract, were estimated.

Results:

The microscopic examination of the lenses indicated that CYP450 inhibitor pre-treatment delayed (fourteenth day) the occurrence of cataract, while CYP450 inducer pretreatment demonstrated an early (ninth day) cataract as compared to galactose control rats (twelfth day). A significant decrease and increase in CYP450 activity was observed with the CYP450 inhibitor and inducer pre-treatment, respectively. There was no alteration in the GSH level, but a significant increase in total and soluble protein was found in groups 3 and 4 as compared to group 2.

Conclusion:

CYP450 may have a role in the initiation of cataract without any effect on the maturation pattern, as revealed by the delayed occurrence of cataract with the CYP450 inhibitor and an early onset of cataract with the CYP450 inducer.

Laser-scanning in vivo confocal microscopy reveals two morphologically distinct populations of stromal nerves in normal human corneas

BACKGROUND

The purpose of this study was to use laser scanning in vivo confocal microscopy to elucidate the location and morphology of stromal nerves in the normal human central cornea.

METHODS

Analysis was performed via an established database of laser-scanning in vivo confocal microscopy on images of the central cornea of normal subjects. The depth and morphology of the stromal nerves were determined.

RESULTS

The population of this study consisted of 99 eyes of 99 healthy subjects (38 male, 61 female). The mean age of the group was 34.7 (SD 13.3, range 13-84) years. Two morphologically different populations of stromal nerves were observed: (1) straight, dichotomous branching nerves; and (2) tortuous nerves with a beaded appearance. The mean recorded depth of straight stromal nerves (186 (SD 66) mum) was significantly deeper than the mean depth of the tortuous stromal nerves (140 (SD 87) mum) (p<0.001).

CONCLUSIONS

The current study identified two morphologically distinct stromal nerve populations in the normal human cornea. We hypothesise that the two morphological nerve populations described here may represent functionally heterogeneous nerves. Further research is required to determine if these in fact represent different types of sensory nerves.

In vivo confocal microscopy of human corneal nerves in health, in ocular and systemic disease, and following corneal surgery: a review

The exponential evolution of in vivo confocal microscopy (IVCM) has led to a significant enhancement in our knowledge of the living cornea in both its physiological and pathological states. Studies using white light and coherent light-based IVCM have enabled detailed quantitative analysis of sub-basal nerve parameters, and have also resulted in the elucidation of the two-dimensional architecture of the normal corneal sub-basal nerve plexus. However, accurate and repeatable methods for quantitative analysis of stromal nerves imaged by IVCM remain to be developed. The effect of corneal surgery on central corneal nerves has been well documented in many IVCM studies, and these studies provide an indication of the regenerative capacity of corneal nerves. IVCM has also clearly demonstrated the involvement of corneal nerves in diseases such as keratoconus, although it remains unclear whether these alterations are a cause of, or occur secondary to, the disease process. IVCM has also been proposed as non-invasive method of accurately diagnosing and assessing the progression of diabetic neuropathy, highlighting the potential application of this technique as an indicator of systemic disease. This review consolidates our knowledge of how IVCM has contributed significantly to our greater understanding of corneal nerves in the living human cornea in health and disease.

The penetration of RealSeal primer and Tubliseal into root canal dentinal tubules: a confocal microscopic study

AIM

To compare penetration depth into dentinal tubules of RealSeal with that of a well-established endodontic sealer (Tubliseal) by means of confocal microscopy.

METHODOLOGY

Twenty sound extracted, single-rooted premolars were selected. Following completion of root canal instrumentation, the teeth were divided into two groups using a stratified sampling method, ranking teeth according to size. In group 1, 10 teeth were filled with Gutta-percha and Tubliseal using cold lateral condensation. In group 2, 10 teeth were filled with RealSeal. Both sealers were labelled with Rhodamine B dye. The teeth were sectioned parallel to their long axis resulting in 20 specimens per group. Confocal microscopy was used to assess the penetration depths of the sealers at three sites for each specimen (coronal, middle and apical). Data were analysed statistically using Stata Release 9.1.

RESULTS

The penetration depth of RealSeal in each one of the thirds of the root canal was found to be higher than that of Tubliseal (P < 0.05). The penetration depths of the two sealers was found to be significantly different (P = 0.001). The mean penetration value for the RealSeal group was 908.8 microm whereas the mean value for the Tubliseal group was 139.5 microm.

CONCLUSIONS

The penetration depth of RealSeal into the root dentinal tubules is significantly greater than that of Tubliseal.

Type 1 Stickler syndrome: a histological and ultrastructural study of an untreated globe

AIMS

To present a histological and ultrastructural study of an untreated globe in a patient with genetically confirmed type 1 Stickler syndrome.

METHODS

Histological and electron microscopic examinations were performed on the enucleated globe from the proband of a pedigree with type 1 Stickler syndrome. Linkage analysis was carried out using polymorphic markers flanking the COL2A1 gene and the mutation was identified by direct sequencing.

RESULTS

The significant retinal abnormality was incarceration of vitreous collagen within glial strands on the inner surface of an atrophic and gliotic detached retina. The incarcerated collagenous layers contained glial cells and extended from the retina to form strands, some of which contributed to a retrolental membrane. Mutation screening detected a C to T mutation in exon 47 that inserted a premature termination codon into the reading frame of the mRNA. Sequence analysis of three of the four affected children confirmed that they were also heterozygous for the base change. The youngest child's DNA was not analysed.

CONCLUSIONS

The study represents the first evidence of abnormal interactions between pathological vitreous collagen and the inner retina in a patient with type 1 Stickler syndrome with a confirmed mutation in the COL2A1 gene.

Bacterial Peptide deformylase inhibitors: a new class of antibacterial agents

Peptide deformylase (PDF) is a prokaryotic metalloenzyme that is essential for bacterial growth but is not required by mammalian cells. Thus, it represents a selective and promising target for the development of new antibacterial agents. Since deformylase inhibitors have yet to be used clinically as antibacterial drugs, compounds targeting this enzyme should avoid cross-resistance with currently used antibacterial agents. The PDF enzyme is a ferrous ion-containing metallohydrolase, but a nickel-containing surrogate is routinely used in the laboratory for testing inhibitors due to its better stability. Enzymes from several bacterial species have been cloned and both their three-dimensional structures and co-crystal structures with bound inhibitor have been determined. As a metallo enzyme, PDF lends itself to the well-precedented mechanism-based rational drug design approach. Using structural and mechanistic information together with high throughput screening, several types of potent PDF inhibitors have been identified. PDF inhibitors identified to date share a common structural feature of a "chelator + peptidomimetic" scaffold. Although compounds with many different chelators inhibit the cell free enzyme, only compounds containing hydroxamic acid or N-formyl hydroxylamine exhibit appreciable antibacterial activity. Several lead inhibitors have demonstrated in vivo efficacy and an excellent safety profile. Two PDF inhibitors, VIC-104959 (LBM415) and BB-83698, have progressed to Phase I clinical trials. In this review, different PDF inhibitors are compared and their biological activities are discussed. Structure-activity relationships have been established and the implications of this work in the design of future PDF inhibitors are considered.

Peptide deformylase inhibitors as antibacterial agents: identification of VRC3375, a proline-3-alkylsuccinyl hydroxamate derivative, by using an integrated combinatorial and medicinal chemistry approach

Peptide deformylase (PDF), a metallohydrolase essential for bacterial growth, is an attractive target for use in the discovery of novel antibiotics. Focused chelator-based chemical libraries were constructed and screened for inhibition of enzymatic activity, inhibition of Staphylococcus aureus growth, and cytotoxicity. Positive compounds were selected based on the results of all three assays. VRC3375 [N-hydroxy-3-R-butyl-3-(2-S-(tert-butoxycarbonyl)-pyrrolidin-1-ylcarbonyl)propionamide] was identified as having the most favorable properties through an integrated combinatorial and medicinal chemistry effort. This compound is a potent PDF inhibitor with a K(i) of 0.24 nM against the Escherichia coli Ni(2+) enzyme, possesses activity against gram-positive and gram-negative bacterial pathogens, and has a low cytotoxicity. Mechanistic experiments demonstrate that the compound inhibits bacterial growth through PDF inhibition. Pharmacokinetic studies of this drug in mice indicate that VRC3375 is orally bioavailable and rapidly distributed among various tissues. VRC3375 has in vivo activity against S. aureus in a murine septicemia model, with 50% effective doses of 32, 17, and 21 mg/kg of body weight after dosing by intravenous (i.v.), subcutaneous (s.c.), and oral (p.o.) administration, respectively. In murine single-dose toxicity studies, no adverse effects were observed after dosing with more than 400 mg of VRC3375 per kg by i.v., p.o., or s.c. administration. The in vivo efficacy and low toxicity of VRC3375 suggest the potential for developing this class of compounds to be used in future antibacterial drugs.

The natural history and treatment of rupture of the anterior cruciate ligament in children and adolescents. A prospective review

A total of 60 children and adolescents with rupture of the anterior cruciate ligament (ACL) was seen between 1980 and 1990. Observation of the 23 patients who were treated conservatively revealed that the natural history of the injury resulted in severe instability and poor function of the knee. Associated meniscal tears were present in 15 knees. Three osteochondral fractures occurred and osteoarthritic changes developed in ten knees. In 1990 therefore we introduced reconstruction of the ACL with a four-strand hamstring graft using an anatomical placement with transphyseal tunnels and anchorage well away from the growth plate. Over a period of nine years, 47 knees underwent reconstruction. The mean follow-up was 49 months (12 to 96). No child suffered physeal damage or leg-length discrepancy. The results were satisfactory in 77% and there was little difference between patients treated before the adolescent growth spurt and those treated during or after this time. These results, however, were not as good as those seen in adults during the same period.

Perioperative considerations in patients with metastatic bone disease

Preoperative assessment of patients with metastatic bone disease includes a history and physical examination, laboratory evaluation, and standard radiographs. Perioperative diagnostics include technetium bone scan, CT scans, MR imaging, positron emission tomography, and biopsy. The role of preoperative tumor embolization and vena cava filter placement is discussed in this article. Guidelines for pain control are provided. Surgical planning and instrument considerations for long bone lesions, periarticular lesions, and pelvis and acetabular lesions are addressed. The importance of rehabilitation for patients with metastatic bone disease is emphasized.

Pyomyositis of the leg with early neurologic compromise

Pyomyositis, although uncommon, is being reported with greater frequency in temperate climates. The presentation is similar to a number of infectious processes, and when associated with a traumatic event, the clinical picture may be confused with that of a musculoskeletal injury. This, coupled with an unfamiliarity of the disease, may result in a delay in diagnosis. Early antibiotic therapy may obviate surgery. Progression to the suppurative stage requires surgical drainage along with antibiotics. CT guided drainage may be accomplished in certain cases. In immunocompromised patients, progression to the septicemic stage is associated with high morbidity and mortality.

Actinonin, a naturally occurring antibacterial agent, is a potent deformylase inhibitor

Peptide deformylase (PDF) is essential in prokaryotes and absent in mammalian cells, thus making it an attractive target for the discovery of novel antibiotics. We have identified actinonin, a naturally occurring antibacterial agent, as a potent PDF inhibitor. The dissociation constant for this compound was 0.3 x 10(-)(9) M against Ni-PDF from Escherichia coli; the PDF from Staphylococcus aureus gave a similar value. Microbiological evaluation revealed that actinonin is a bacteriostatic agent with activity against Gram-positive and fastidious Gram-negative microorganisms. The PDF gene, def, was placed under control of P(BAD) in E. coli tolC, permitting regulation of PDF expression levels in the cell by varying the external arabinose concentration. The susceptibility of this strain to actinonin increases with decreased levels of PDF expression, indicating that actinonin inhibits bacterial growth by targeting this enzyme. Actinonin provides an excellent starting point from which to derive a more potent PDF inhibitor that has a broader spectrum of antibacterial activity.

Potent inhibitory ligands of the GRB2 SH2 domain from recombinant peptide libraries

We cloned and expressed the SH2 domain of human GRB2 as glutathione S-transferase and maltose binding protein fusion proteins. We screened three phagemid-based fd pVIII-protein phage display libraries against SH2 domain fusion proteins. Sequence analysis of the peptide extensions yielded a variety of related peptides. By examining the ability of the phage clones to bind other SH2 domains, we demonstrated that the phage were specific for the SH2 domain of GRB2. Based on the sequence motif identified in the "random" library screening experiment, we also built and screened a phage display library based on a Tyr-X-Asn motif (X5-Tyr-X-Asn-X8). To examine the affinity of the phage derived peptides for GRB2, we set up a radioligand competition binding assay based on immobilized GRB2 and radiolabelled autophosphorylated EGFR ICD as the radioligand. Results obtained with peptide competitors derived from the phage sequences demonstrated that nonphosphotyrosine-containing peptides identified with the phage display technology had an affinity for the receptor similar to tyrosine-phosphorylated peptides derived from the EGFR natural substrate. Interestingly, when the phage display peptides were then phosphorylated on tyrosine, their affinity for GRB2 increased dramatically. We also demonstrated the ability of the peptides to block the binding of the GRB2 SH2 domain to EGFR in a mammalian cell-based binding assay.

Treatment of limited motion after anterior cruciate ligament reconstruction

Limited motion or arthrofibrosis after anterior cruciate ligament (ACL) reconstruction causes significant pain and functional impairment. Based on physical findings and loss of motion compared with the opposite normal knee, classification systems for the diagnosis and treatment of arthrofibrosis have been developed. The operative techniques and preoperative and postoperative rehabilitation and management are discussed. Range of motion (ROM) problems after ACL reconstruction have been minimized by improved surgical techniques and perioperative rehabilitation programs. The most effective treatment for arthrofibrosis is prevention by delaying ACL reconstruction until the patient has a normal gait and full ROM and minimal swelling in the injured knee and by appropriate ROM exercises after surgery.

The natural history of acute, isolated, nonoperatively treated posterior cruciate ligament injuries. A prospective study

We sought to determine prospectively the natural history of acute, isolated, nonoperatively treated posterior cruciate ligament injuries in athletically active patients. The study population consisted of 133 patients (average age, 25.2 years at time of injury). All patients completed a subjective questionnaire each year for an average of 5.4 years (range, 2.3 to 11.4). Sixty-eight of the 133 patients returned to the clinic for long-term follow-up evaluation. Objectively, physical examination revealed no change in laxity from initial injury to follow-up. No correlation was found between radiographic joint space narrowing and grade of laxity. The mean modified Noyes knee score was 84.2 points, the mean Lysholm score was 83.4, and the mean Tegner activity score was 5.7. Patients with greater laxity did not have worse subjective scores. No correlation was found between subjective knee scores and time from injury. Regardless of the amount of laxity, half of the patients returned to the same sport at the same or higher level, one-third returned to the same sport at a lower level, and one-sixth did not return to the same sport. Results of this study suggest that athletically active patients with acute isolated posterior cruciate ligament tears treated nonoperatively achieved a level of objective and subjective knee function that was independent of the grade of laxity.

Study of pulmonary function tests in 2000 healthy persons in Gujarat

This paper reports the results of spirometric studies done in the state of Gujarat in view of deriving the ventilatory norms. The study included a total of 2000 healthy nonsmoker individuals with 1369 males and 631 females. The study was done over the period from September, '92 to July, '93. The observations were tabulated, data fed on computers and the normal values for the parameters viz peak expiratory flow rate (PEFR), forced expiratory volume--1st second (FEV1) and forced vital capacity (FVC) were derived at.

Combinatorial synthesis and screening of a chemical library of 1,4-dihydropyridine calcium channel blockers

Solid-phase synthesis of a 300-member pharmacophore library of 1,4-dihydropyridines from keto ester, diketone and aldehyde building blocks on a cleavable amine polymeric support is described. Screening and serial deconvolution of the combinatorial library has resulted in identification of known and new potent calcium channel blockers.

Rational design and combinatorial evaluation of enzyme inhibitor scaffolds: identification of novel inhibitors of matrix metalloproteinases

The discovery of a novel series of heterocyclic matrix metalloproteinase (MMPs) inhibitors is described. Published crystal structures of peptidyl hydroxamates bound to MMPs were the basis for the rational design of diketopiperazine (DKP) inhibitors. Combinatorial libraries were prepared and evaluated for their ability to inhibit collagenase-1, stromelysin-1, and gelatinase-B substrate hydrolysis. Deconvolution of active pools resulted in the identification of potent inhibitors (IC50's < 100 nM) of collagenase-1 and gelatinase-B, with the most potent inhibitor exhibiting an IC50 of 30 nM against collagenase-1. A description of the combinatorial evaluation process, as well as initial SAR interpretation for this novel series, is provided.

Malonyl alpha-mercaptoketones and alpha-mercaptoalcohols, a new class of matrix metalloproteinase inhibitors

A novel series of matrix metalloproteinase (MMP) inhibitors is described. Incorporation of a terminal alpha-mercaptoketone or alpha-mercaptoalcohol in the zinc binding domain of a series of inhibitors led to compounds exhibiting low nanomolar activity against collagenase-1 (MMP-1), stromelysin (MMP-3), and gelatinase-B (MMP-9).

The asymmetric synthesis and in vitro characterization of succinyl mercaptoalcohol and mercaptoketone inhibitors of matrix metalloproteinases

A series of succinyl based mercaptoketones and diastereomeric mercaptoalcohols were prepared and evaluated in vitro as inhibitors of the matrix metalloproteinases collagenase-1 (MMP-1), stromelysin (MMP-3), and gelatinase-B (MMP-9).

Osteonecrosis of the knee: current clinical concepts

Osteonecrosis of the knee should be differentiated into two main categories: (1) primary, spontaneous, or idiopathic osteonecrosis and (2) secondary osteonecrosis (e.g., secondary to factors such as steroid therapy, systemic lupus erythematosus, alcoholism, Caisson decompression sickness, Gaucher's disease, hemoglobinopathies, etc.). Spontaneous or primary osteonecrosis of the knee presents with an acute knee pain in elderly patients. It is three times more common in women than in men. Traumatic and vascular theories have been proposed as a causative factor of osteonecrosis of the knee, but the precise etiology still remains speculative. High index of clinical awareness and a good history and physical examination are essential to make an early, accurate diagnosis. Plain radiographs are often normal during the early course of the disease and, in such instances, radioisotope bone scan and magnetic resonance imaging may be helpful. In the early stage of the disease, nonoperative treatment is indicated and many patients, if diagnosed early, have a benign course with a satisfactory pain relief and a good knee function. In patients with advanced stage of the disease, treatment options include arthroscopic debridement, curettage or drilling of the lesion, bone grafting, high tibial osteotomy, use of osteochondral allograft, and unicompartmental or total knee arthroplasty. The choice of treatment should be based on factors such as age of the patient, severity of symptoms, activity level and functional demands on the knee, site and stage of the lesion, and extent of deformity and secondary osteoarthritis. The clinical features and treatment of steroid-induced osteonecrosis of the knee are briefly discussed. In recent years, "postmeniscectomy" osteonecrosis has been reported, but at present its prevalence and pathophysiology remain unknown. It is possible that this may be a preexisting condition that was not recognized at the time of initial consultation or osteonecrosis may develop after meniscectomy in occasional cases.

Classification and management of arthrofibrosis of the knee after anterior cruciate ligament reconstruction

We report 72 patients with disabling knee arthrofibrosis who were treated at our clinic. All patients had painful restriction of extension or limitation of both extension and flexion that had persisted despite physical therapy. The level of arthrofibrosis was categorized into one of four types: Type 1 (25 patients), < 10 degree extension loss and normal flexion; Type 2 (16 patients), > 10 degree extension loss and normal flexion; Type 3 (15 patients), > 10 degree extension loss and > 25 degree flexion loss with a tight patella; and Type 4 (16 patients), > 10 degree extension loss, 30 degrees or more flexion loss, and patella infera with marked patellar tightness. All patients were treated with outpatient arthroscopic surgery. Anterior scar resection down to the proximal tibia was required for all patients with Types 2, 3, and 4 arthrofibrosis. Notchplasty was performed when necessary. Medial and lateral capsular releases and knee manipulation were required for patients with Type 3 or 4 arthrofibrosis. Postoperatively, all patients with Types 2, 3, and 4 arthrofibrosis were treated with outpatient serial extension casting. At the time of latest followup (28 to 115 months), the mean improvement of range of motion was as follows: Type 1, 7 degrees of extension; Type 2, 14 degrees of extension; Type 3, 13 degrees of extension and 28 degrees of flexion; and Type 4, 18 degrees of extension and 27 degrees of flexion. Improvement was also found for the mean stiffness, self-evaluation, functional activity, and Noyes knee scores in all groups.

Hydroxamic acid-based bisubstrate analog inhibitors of Ras farnesyl protein transferase

The rational design, synthesis, and activity of novel, hydroxamic acid-based, collective bisubstrate analog inhibitors of farnesyl protein transferase (FPT) is described. This class of compounds differ structurally from the conventional FPT inhibitors by being non-sulfhydryl and by being bisubstrate based rather than peptide or FPP derived inhibitors. Whereas replacement of the sulfhydryl group of tetrapeptide CVLS (I50 = 1 microM) by an N-methylhydroxamic acid had a deleterious effect (10, I50 > 360 microM), moderate inhibition was realized with 16 (I50 = 42.5 microM), a bisubstrate analog involving anchorage of farnesyl and tripeptide groups by a hydroxamic acid-embedded linker. Starting from 16, a 1 order of magnitude improvement in in vitro potency was obtained by optimization of the linker (20, I50 = 4.35 microM). An additional 13-fold enhancement was achieved by substituting the tripeptide moiety VLS in 20 by VVM (23, I50 = 0.33 microM). The dependence of these inhibitors on their peptide and farnesyl subunits is suggestive of their bisubstrate nature. Compound 23 (I50 = 0.33 microM) is 2 orders of magnitude better in activity compared to the initial lead 16 [I50 = 42.5 microM) and is effective in blocking prenylation of protein in whole cells including p21ras.

Anterior cruciate ligament reconstruction in athletes with an ossicle associated with Osgood-Schlatter's disease

We report a series of 20 athletes with an ossicle associated with Osgood-Schlatter's disease (OSD) who underwent anterior cruciate ligament (ACL) reconstruction using autogenous, central-10-mm patellar-tendon graft. All patients had an Osgood Schlatter's lesion with an ossicle as seen on a plain radiograph. The patients were reviewed at an average follow-up of 44 months (range, 24 to 108 months). The postoperative assessment included clinical examination, KT-1000 testing, isokinetic testing, and subjective score (using the modified Noyes' questionnaire). At the time of latest review, all 20 patients had a stable knee. The average side-to-side difference on manual maximum KT-1000 assessment was 1.9 mm (range, 0 to 5 mm). Average time to return to full sporting activities was 5.2 months (range, 2.6 to 8.9 months). All patients returned to their previous level of activity. The mean modified Noyes' knee score was 96 (range, 89 to 100). To date, no graft failure has occurred. Based on the results of this study, we believe that ACL reconstruction using the autogenous bone-patellar tendon-bone graft can be safely undertaken in athletes with an ossicle associated with OSD without compromising the final knee function.

Rehabilitation after meniscal repair

Meniscal repair as an isolated procedure should be considered for patients who present with clinically symptomatic meniscal tears and who have large, unstable, peripheral, bucket-handle meniscal tears at arthroscopy. Successful repair relieves meniscal symptoms and allows the patient to return to full function. In the authors' study population, patients with adequate repair of the meniscal tears followed a rehabilitation program that allowed immediate ROM and weight bearing as tolerated. They achieved a clinical result comparable to patients who followed a restrictive rehabilitation program. By using a less restrictive rehabilitation program, surgeons may offer patients who require meniscal repairs a program with a shorter interval between the surgical procedure and full return to the activities of daily living and athletics than was offered by previous regimens. From the evidence obtained from the study population using the authors' selection criteria and surgical technique, the accelerated rehabilitation program does not compromise the clinical result. The follow-up period is too short to determine if repair will be successful in protecting the knee joint from the known degenerative changes that follow meniscectomy. It is certain, however, that surgical repair that preserves meniscal tissue can relieve symptoms and allow patients to return to activities at their own pace. Many questions remain to be answered, all of which need to be addressed in the future: What is the natural history of an untreated meniscal tear in an ACL-stable and in an ACL-injured knee? Is suturing necessary for meniscal tears? If so, what type of suturing technique should be used? Is some type of meniscal abrasion or stimulation of the meniscal tear needed to obtain healing? What is the likelihood of a healed, repaired meniscus to retear in the future, even if the initial repair has been successful, especially on the medial side? At present, there is no universal agreement as to what rehabilitation protocol is best. For the past 8 years, the authors have undertaken an accelerated rehabilitation program following isolated meniscal repairs and also following repairs performed in conjunction with ACL reconstructions. With constant patient evaluation and follow-up, clinically successful results have been achieved. A well-designed, prospective, multicenter study of isolated meniscal repair comparing different rehabilitation protocols is desirable to resolve the existing controversial issue of rehabilitation after meniscal repair.

Resolution of intracranial calcifications in infants with treated congenital toxoplasmosis

PURPOSE

To determine the natural history of intracranial calcifications in infants with treated congenital toxoplasmosis.

MATERIALS AND METHODS

Between January 1982 and March 1994, cranial computed tomography was performed in 56 infants with treated congenital toxoplasmosis when they were newborns and approximately 1 year old. Locations and sizes of intracranial calcifications were noted.

RESULTS

Forty newborns had intracranial calcifications. By 1 year of age, calcifications diminished or resolved in 30 (75%) and remained stable in 10 (25%) of these treated infants. Ten (33%) of the 30 infants whose calcifications diminished versus seven (70%) of the 10 infants with stable calcifications received less intensive antimicrobial treatment than the other treated infants. In contrast, a small number of infants who were untreated or treated 1 month or less had intracranial calcifications that increased or remained stable during their 1st year of life.

CONCLUSION

Diminution or resolution of intracranial calcifications was an unexpected and remarkable finding in infants with treated, congenital toxoplasmosis, consonant with their improved neurologic functioning.

Development of highly potent inhibitors of Ras farnesyltransferase possessing cellular and in vivo activity

Analogs of CVFM (a known nonsubstrate farnesyltransferase (FT) inhibitor derived from a CA1A2X sequence where C is cysteine, A is an aliphatic residue, and X is any residue) were prepared where phenylalanine was replaced by (Z)-dehydrophenylalanine, 2-aminoindan-2-carboxylate, 1,2,3,4-tetrahydroisoquinoline-3-carboxylate (Tic), and indoline-2-carboxylate. The greatest improvement in FT inhibitory potency was observed for the Tic derivative (IC50 = 1 nM); however, this compound was ineffective in blocking oncogenic Ras-induced transformation of NIH-3T3 fibroblast cells. A compound was prepared in which both the Cys-Val methyleneamine isostere and the Tic replacement were incorporated. This derivative inhibited FT with an IC50 of 0.6 nM and inhibited anchorage-independent growth of stably transformed NIH-3T3 fibroblast cells by 50% at 5 microM. Replacing the A1 side chain of this derivative with a tert-butyl group and replacing the X position with glutamine led to a derivative with an IC50 of 2.8 nM and an EC50 of 0.19 microM, a 26-fold improvement over (S*,R*)-N-[[2-[N-(2-amino-3-mercaptopropyl)-L-valyl]-1,2,3,4- tetrahydro-3-isoquinolinyl]carbonyl]-L-methionine. This derivative, (S*,R*)-N-[[2-[N-(2-amino-3-mercaptopropyl)-L-tert-leucyl]-1,2,3,4 - tetrahydro-3-isoquinolinyl]-carbonyl]-L-glutamine, was evaluated in vivo along with (S*,R*)-N-[[2-[N-(2-amino-3- mercaptopropyl)-L-tert-leucyl]-1,2,3,4-tetrahydro-3- isoquinolinyl]carbonyl]-L-methionine methyl ester for antitumor activity in an athymic mouse model implanted ip with H-ras-transformed rat-1 tumor cells. When administered by injection twice a day at 45 mg/kg for 11 consecutive days, both compounds showed prolonged survival time (T/C = 142-145%), thus demonstrating efficacy against ras oncogene-containing tumors in vivo.

Management of anterior cruciate ligament injuries in skeletally immature adolescents

Anterior cruciate ligament (ACL) injuries in skeletally immature adolescents are being diagnosed and reported with increasing frequency. Nonoperative management of mid-substance ACL injuries in adolescent athletes frequently results in a high incidence of giving-way episodes, recurrent meniscal tears, and early onset of osteoarthritis. An intraarticular ACL reconstruction (using the central 10-mm patellar tendon graft) in young athletes approaching skeletal maturity provides predictable excellent knee stability, and the athletes are able to return to competitive sports with a decreased risk of recurrent meniscal and/or chondral injury. Guidelines for the management of ACL injuries in skeletally immature adolescents are presented.

alpha-Hydroxy phosphinyl-based inhibitors of human renin

The design and application of alpha-hydroxy phosphonates, a new class of transition state analogs, toward the discovery of novel and potent inhibitors of the aspartyl protease renin is described. Tripeptidic alpha-hydroxy diethyl phosphonate 3, the first example in this series, was found to be a good inhibitor of human renin (IC50 = 29 nM), and preliminary studies led to the choice of alpha-hydroxy dimethyl phosphonate 15 (IC50 = 16 nM) as a base-line compound for further structure-activity relationship study. Corresponding phosphinate (28-30) and phosphine oxide (23 and 24) analogs of 15 were prepared to assess the steric and electronic requirements around the phosphorus center. Evaluation of these analogs suggested that the presence of at least one alkoxy group on phosphorus was a critical requirement for good activity. Inhibitors with leucine at P2 possessed better in vitro activity than the corresponding P2 histidine analogs (15, IC50 = 16 nM vs 37, IC50 = 220 nM; 33, IC50 = 8.5 nM vs 40, IC50 = 41 nM). Compound 34 (IC50 = 31 nM), the P3 aminocaproic analog of 15, showed complete and long-lasting inhibition of plasma renin activity while eliciting a 10-15 mmHg drop in mean arterial pressure when administered intravenously at 1 mumol/kg in conscious, sodium-depleted, cynomolgus monkeys. In summary, the alpha-hydroxy phosphonates represent a promising and structurally novel class of transition state analog inhibitors of human renin.

Anterior cruciate ligament injuries in young athletes. Recommendations for treatment and rehabilitation

Complete midsubstance tears of the anterior cruciate ligament (ACL) in skeletally-immature adolescents are being diagnosed and reported with increasing frequency. Conservative treatment of such ACL tears in junior high schools, subsequent meniscal tears, and very early osteoarthritis. Results of primary repair of the torn ACL and extra-articular reconstructive procedures have been disappointing. Intra-articular ACL reconstruction in young athletes approaching skeletal maturity using the autogenous patellar tendon graft gives excellent knee stability, and decreases the risk of meniscal tears. Athletes are able to return to competitive sports at their preinjury level. Here, the existing literature on the subject of midsubstance ACL tears in young athletes is reviewed, and guidelines for the management of ACL-deficient knee in this population are provided.